U.S. patent application number 13/550407 was filed with the patent office on 2012-11-08 for devices and methods for cutting tissue.
This patent application is currently assigned to LAURIMED, LLC. Invention is credited to Brian R. DUBOIS, Alexander GORDON, James T. NIELSEN.
Application Number | 20120283742 13/550407 |
Document ID | / |
Family ID | 45400250 |
Filed Date | 2012-11-08 |
United States Patent
Application |
20120283742 |
Kind Code |
A1 |
DUBOIS; Brian R. ; et
al. |
November 8, 2012 |
DEVICES AND METHODS FOR CUTTING TISSUE
Abstract
Various medical devices and methods for cutting and/or
evacuating tissue are provided. The devices and methods may utilize
a reciprocating mechanism or motor powered by suction from a vacuum
source. The medical devices and methods may be used on tissue in
various regions of a patient's body and for treating various
conditions, e.g., for performing a polypectomy or discectomy.
Inventors: |
DUBOIS; Brian R.; (Redwood
City, CA) ; NIELSEN; James T.; (San Francisco,
CA) ; GORDON; Alexander; (Menlo Park, CA) |
Assignee: |
LAURIMED, LLC
Redwood City
CA
|
Family ID: |
45400250 |
Appl. No.: |
13/550407 |
Filed: |
July 16, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13174416 |
Jun 30, 2011 |
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13550407 |
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61360429 |
Jun 30, 2010 |
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61377883 |
Aug 27, 2010 |
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Current U.S.
Class: |
606/115 |
Current CPC
Class: |
A61B 2017/00261
20130101; A61B 2017/320064 20130101; A61B 2017/00269 20130101; A61B
2017/00561 20130101; A61B 17/32002 20130101; A61B 2017/320028
20130101; A61B 2017/320008 20130101 |
Class at
Publication: |
606/115 |
International
Class: |
A61B 17/32 20060101
A61B017/32 |
Claims
1. A medical device driven by a vacuum source, the device
comprising: a working end having an operable element, the operable
element coupled to a mechanism, such that when the mechanism is
driven by the vacuum source movement of a drive shaft actuates the
operable element; where the drive shaft is located in a chamber and
moveable between a drive stroke and a return stroke; a shuttle body
moveable between a Forward and return positions, wherein movement
between the forward and return positions alternates a fluid path
between the chamber and vacuum source so that during application of
a vacuum from the vacuum source movement of the shuttle body causes
the drive shaft to cycle between the drive stroke and the return
stroke; and a linkage coupling the drive shaft to the shuttle body
such that as the drive shaft approaches the end of the drive or
return stroke the linkage transfers a force to the shuttle body to
assist in switching between the forward and return positions and
prevents unstable flutter of the shuttle body between the forward
and return positions.
2. The medical device of claim 1, where the linkage comprises a
bi-stable switch that is stable in at least a first or a second
position and is unstable between the first and second position.
3. The device of claim 1, wherein the operable element comprises a
motion selected from the group consisting of rotary motion, linear
motion, and reciprocating motion.
4. The device of claim 1, where the working end further comprises
an elongate shalt wherein the elongate shaft has a lumen capable of
being fluidly coupled to a supply of an irrigant, wherein the
irrigant does not flow through the lumen unless vacuum from the
vacuum source draw the irrigant through the lumen.
5. The device of claim 1, further comprising a handle coupled to
the working end.
6. The device of claim 5, where the mechanism is located in the
handle.
7. The device of claim 1, wherein the working end comprises a
malleable shaft portion, wherein the operable element is
reciprocated within the malleable portion.
8. The device of claim 1, where the working end further comprises
an electrocautery element positioned at a distal end of the working
end.
9. The device of claim 1, where the working end further comprises a
delivery lumen capable of delivering a therapeutic substance.
10. The device of claim 1, where the mechanism drive shaft,
chamber, and shuttle body are fabricated from a polymer.
11. The device of claim 1, further comprising an evacuation lumen,
such that vacuum can pull debris through the evacuation lumen.
12. The device of claim 1, further comprising a scraping edge at
the working end.
13. The device of claim 1, where the drive shaft is moveable in a
rotating motion.
14. The device of claim 1, where the drive shaft is moveable in a
linear motion.
15. A medical device for use with a supply source, comprising: a
working end having an operable element; a motor comprising: a
supply port for fluidly coupling to the supply source; a first
chamber with a drive piston moveably located therein and having a
first drive port and a second drive port on respective ends of the
chamber that are fluidly isolated from each other; a second chamber
with a shuttle body moveably located therein and capable of
switching between a first and second position; such that in the
first position the shuttle body fluidly couples the first drive
port to the supply port and in the second position the shuttle body
fluidly couples the second drive port to the supply port where such
alternate coupling results in movement of the drive piston between
a drive stroke and a return stroke; a linkage coupling a portion of
the drive piston to the shuttle body such that as the drive piston
approaches the end of the respective drive and return motion, the
linkage transfers a force to the shuttle body to assist in
switching between the first and second positions preventing
unstable flutter of the shuttle body between the first and second
positions; and where the operable element is mechanically coupled
to the drive piston such that movement of the drive piston causes
actuation of the operating element.
16. The medical device of claim 15, where the medical device is
configured for use with a vacuum source or a compressed air source.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. patent
application Ser. No. 13/174,416 filed Jun. 30, 2011 which claims
benefit of priority to U.S. Provisional Patent Application Ser. No.
61/360,429 filed Jun. 30, 2010 and U.S. Provisional Patent
Application Ser. No. 61/377,883 filed Aug. 27, 2010, all of which
are incorporated by reference herein in their entirety for all
purposes.
FIELD OF THE INVENTION
[0002] The present devices and methods relate generally to medical
devices and methods for cutting and/or evacuating tissue from
various regions of a patient's body.
BACKGROUND
[0003] Many common medical devices perform the function of
resecting tissue. Suction, supplied by an external vacuum source is
often used to evacuate tissue from the operative site.
[0004] Medical devices which cut and evacuate tissue are used in a
variety of procedures, including ear, nose, and throat surgery,
gynecological surgery, spinal surgery, ophthalmic surgery, and many
other applications. Depending on the procedure, the evacuated
tissue may be collected for pathological analysis.
[0005] When applied to ear, nose, and throat surgery, tissue
resecting devices are commonly referred to as microdebriders.
[0006] Tissue incision may be performed by either a rotating cutter
(unidirectional or oscillating) or a reciprocating cutter. In the
case of a rotating cutter, an electric motor is commonly used as
the source of motion. In the case of a reciprocating cutter, motion
may be produced by manual actuation, through a control such as a
button or trigger, or powered actuation using pulsed or valved
compressed air. Each of these power sources has distinct
disadvantages when used to power a resecting medical device.
[0007] For example, when an electric motor is used to provide
rotational motion of a cutter, the additional weight of the
electric motor may cause operator fatigue. Wires from an external
power supply are inconvenient to make the connections and it is
inconvenient to have the wires attached to the device during
use.
[0008] An electric motor increases the total cost of a device
because of the relatively high cost of the motor itself and the
cost of a power supply (in the case of an externally powered motor)
or the cost of a recharging unit (when rechargeable batteries are
used). The addition of electric motors makes sterilization of the
device more difficult, e.g., because of the added mass to the
device from the motors. Additionally, the presence of batteries
reduces the sterilization options available to the manufacturer,
due to the heat generated by certain sterilization techniques. The
presence of batteries adds potentially toxic chemicals that present
additional challenges related to toxicity, sterilization, and
device disposal.
[0009] Medical devices that include electric motors are often made
to be re-usable which requires a system for reprocessing the
device. When using a manually actuated cutting device, the operator
may experience fatigue from repeated actuations. Additionally,
manual actuations can be performed only as quickly as the operator
can actuate the cutter via mechanical input through a control and
the time required to perform an adequate number of actuations may
be excessive.
[0010] Electrically-powered microdebriders typically require an
expensive capital investment in a power console that is separate
from the handpiece. The capital cost of the power console,
handpiece, and disposable blades makes procedures such as a nasal
polypectomy and other procedures cost prohibitive in a doctor's
clinic setting.
[0011] Existing microdebriders are typically built with a handle of
the device in line with the shall of the device, as a result, the
handle and the operator's hand may interfere with an endoscope
and/or the camera.
[0012] Existing microdebriders expose a cutting blade to the end of
the device. This may be disadvantageous when the operator loses
sight of the end of the device and accidentally cuts or damages
structures that come into contact with it.
[0013] As a result of these limitations, it is impractical for Ear,
Nose, and Throat physicians to remove nasal and sinus polyps or
other tissue in an office or other setting using the current
technology. Therefore, patients are left with the undesirable
options of a course of steroid treatments to reduce the size of the
polyps (with associated steroid side effects), removal of the
polyps in an ambulatory surgery center (cost prohibitive and
therefore rarely performed as a stand-alone procedure), or leaving
the polyps untreated and dealing with the associated breathing
obstruction.
BRIEF SUMMARY
[0014] Various medical devices and methods for cutting and/or
evacuating tissue from various regions of a patient's body are
provided herein.
[0015] Various cutting device driven by various power sources are
described herein. In certain variations, a vacuum powered tissue
cutting device is provided. In one variation, the device includes a
medical device driven by a vacuum source comprising a working end
having an operable element, the operable element coupled to a
mechanism, such that when the mechanism is driven by the vacuum
source movement of a drive shaft actuates the operable element;
where the drive shaft is located in a chamber and moveable between
a drive stroke and a return stroke; a shuttle body moveable between
a forward and return positions, wherein movement between the
forward and return positions alternates a fluid path between the
chamber and vacuum source so that during application of a vacuum
from the vacuum source movement of the shuttle body causes the
drive shall to cycle between the drive stroke and the return
stroke; and a linkage coupling the drive shaft to the shuttle body
such that as the drive shall approaches the end of the drive or
return stroke the linkage transfers a force to the shuttle body to
assist in switching between the forward and return positions and
prevents unstable flutter of the shuttle body between the forward
and return positions.
[0016] In one variation, the linkage comprises a bi-stable switch
that is stable in at least a first or a second position and is
unstable between the first and second position.
[0017] Examples of the device in include operable elements that
comprise a motion selected from the group consisting of rotary
motion, linear motion, and reciprocating motion.
[0018] In another variation, the working end further comprises an
elongate shaft wherein the elongate shaft has a lumen capable of
being fluidly coupled to a supply of an irrigant, wherein the
irrigant does not flow through the lumen unless vacuum from the
vacuum source draw the irrigant through the lumen.
[0019] Devices described herein can include a handle coupled to the
working end. Optionally, the mechanism can be located in the
handle.
[0020] Variations of the devices can include a working end with a
malleable shaft portion, wherein the operable element is
reciprocated within the malleable portion; an electrocautery
element positioned at a distal end of the working end; a working
end with a delivery lumen capable of delivering a therapeutic
substance; an evacuation lumen, such that vacuum can pull debris
through the evacuation lumen; a scraping edge at the working
end.
[0021] In additional variations, the mechanism drive shaft,
chamber, and shuttle body are fabricated from a polymer.
[0022] Yet another variation of the devices described herein
includes a medical device for use with a supply source. One example
includes a working end having an operable element; a motor
comprising: a supply port for fluidly coupling to the supply
source; a first chamber with a drive piston moveably located
therein and having a first drive port and a second drive port on
respective ends of the chamber that are fluidly isolated from each
other; a second chamber with a shuttle body moveably located
therein and capable of switching between a first and second
position; such that in the first position the shuttle body fluidly
couples the first drive port to the supply port and in the second
position the shuttle body fluidly couples the second drive port to
the supply port where such alternate coupling results in movement
of the drive piston between a drive stroke and a return stroke; a
linkage coupling a portion of the drive piston to the shuttle body
such that as the drive piston approaches the end of the respective
drive and return motion, the linkage transfers a force to the
shuttle body to assist in switching between the first and second
positions preventing unstable flutter of the shuttle body between
the first and second positions; and where the operable element is
mechanically coupled to the drive piston such that movement of the
drive piston causes actuation of the operating element.
[0023] The medical devices described herein can be configured for
use with a vacuum source or a compressed air source.
[0024] The device may include an elongate shaft having a proximal
end, a distal end and a lumen defined therein. The distal end may
include an opening for receiving tissue. A cutter may be positioned
within the elongate shaft, wherein the cutter is configured to be
actuated to cut tissue. A chamber may be coupled to the proximal
end of the elongate shaft. For example, the chamber may be coupled
to the elongate shaft such that the elongate shaft remains fixed
relative to the chamber. The chamber may have a mechanism
positioned therein, wherein the mechanism can be powered by suction
created by a vacuum source such that the mechanism produces an
actuating motion which causes the cutter to actuate, e.g., to
reciprocate. In certain variations, a cutter positioned within the
elongate shaft may be reciprocated past the opening in the elongate
shaft to cut tissue in the opening.
[0025] In certain variations, a method of cutting and/or removing
tissue from a subject may include advancing a cutting device next
to, near or to a target tissue in the subject. The cutting device
may have an elongate shaft and a cutter positioned within the
elongate shaft. The cutting device may be powered using suction
created by a vacuum source such that the cutting device produces an
actuating motion, which causes the cutter to actuate, e.g.,
reciprocate, to cut tissue. The cut tissue may be evacuated using
the suction created by the vacuum source or may be otherwise
removed. In certain variations, the method of cutting and/or
removing tissue may be utilized to perform a polypectomy or a
discectomy.
[0026] In certain variations, an apparatus for cutting or scraping
tissue in a subject may be provided. The apparatus may include an
end effector, wherein the end effector includes a scraping edge
positioned on a distal end of the end effector. One or more
scraping wings may be positioned at an angle relative to the
scraping edge such that the scraping edge and scraping wings may be
used to provide scraping motions in different directions.
[0027] In certain variations, devices, systems and methods for
excising, cutting and/or evacuating tissue are provided. A
variation of a device may include a cutter and a double action
vacuum powered mechanism or motor in which vacuum is used to
actively reciprocate a piston connected to the cutter. The vacuum
powered motor may include a vacuum port connected to a vacuum
source, a shuttle piston, a drive piston coupled to the shuttle
piston, and a chamber for receiving the drive piston, the chamber
having proximal and distal sides. The drive piston may be set into
reciprocating motion through the creation of differential pressure
on either side of the piston by alternating evacuation, through the
vacuum port, within the two sides of the piston chamber. The motion
of the drive piston may effect translation of the shuttle piston,
causing the shuttle piston to alternate between positions of
opening and closing the vacuum port to the proximal and distal
sides of the piston chamber to alternate evacuation of each side of
the chamber. The actuating motion, e.g., reciprocating motion, of
the drive piston may be used to reciprocate or rotate the
cutter.
[0028] In certain variations, a cutting or scraping component may
be positioned or located at or near a distal end of a rigid or
flexible end effector which may be utilized to excise, scrape or
cut tissue. The end effector may be curved or straight. The end
effector may include a shall, a reciprocating cutter and/or a
scraping edge positioned on the shalt or on the reciprocating
cutter.
[0029] In certain variations, a cutter may be positioned at or near
the distal end of a malleable shaft that may be shaped by the
operator to a curvature suitable to access the desired anatomical
location.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0030] FIG. 1A illustrates a side view of a variation of a cutting
device.
[0031] FIG. 1B illustrates a side view of the cutting device of
FIG. 1A with the right hand portion of the chamber hidden.
[0032] FIG. 1C illustrates a side view of the cutting device of
FIG. 1B with the rigid sleeve and elongate shaft hidden to show the
evacuation shaft.
[0033] FIG. 1D illustrates a side view of the cutting device of
FIG. 1B with the manifold of the vacuum powered mechanism
hidden.
[0034] FIG. 1E illustrates a side view of the cutting device of
FIG. 1B with the collection chamber hidden to show a filter.
[0035] FIG. 1F illustrates a magnified view the elongate shaft of
the cutting device of FIG. 1B having multiple lumens.
[0036] FIG. 1G illustrates a magnified view of the cutter of the
cutting device of FIG. 1B.
[0037] FIG. 1H illustrates a vacuum source coupled to a variation
of the cutting device.
[0038] FIG. 2A illustrates a side view of a variation of a vacuum
powered mechanism.
[0039] FIG. 2B illustrates a cross sectional view of the vacuum
powered mechanism of FIG. 2A.
[0040] FIG. 2C illustrates an opposite side view of the vacuum
powered mechanism of FIG. 2A.
[0041] FIG. 2D illustrates a front view of the vacuum powered
mechanism of FIG. 2A.
[0042] FIG. 2E illustrates a rear view of the vacuum powered
mechanism of FIG.
[0043] FIGS. 2F-2G illustrate side and prospective cross sectional
views of the vacuum powered mechanism of FIG. 2A in a first
position.
[0044] FIGS. 2H-2I illustrate side and prospective cross sectional
views of the vacuum powered mechanism of FIG. 2A in a second
position.
[0045] FIG. 3A illustrates a cross sectional view of a variation of
a double action vacuum powered mechanism having a bi-stable switch
in a proximal position.
[0046] FIG. 3B illustrates a cross sectional view of the double
action vacuum powered mechanism having a bi-stable switch of FIG.
3A in a distal position.
[0047] FIG. 4A illustrates the cross sectional view of a variation
of a double action vacuum powered mechanism in a proximal
position.
[0048] FIG. 4B illustrates a cross sectional view of the double
action vacuum powered mechanism of FIG. 4A in a distal
position.
[0049] FIG. 5A illustrates a cross sectional view of a variation of
a single action vacuum powered mechanism using a spring return
system in a proximal position.
[0050] FIG. 5B illustrates a cross sectional view of a single
action vacuum powered mechanisms of FIG. 5A in a distal
position.
[0051] FIG. 6 illustrates a side view of a variation of an end
effector.
[0052] FIG. 7 illustrates a side view of a variation of an end
effector.
[0053] FIG. 8 illustrates a flow chart of a variation of a method
for cutting and removing tissue using a vacuum powered cutting
device.
[0054] FIG. 9 illustrates a flow chart of a variation of a method
for performing a polypectomy using a vacuum powered cutting
device.
[0055] FIG. 10 illustrates a flow chart of a variation of a method
for performing a discectomy using a vacuum powered cutting
device.
DETAILED DESCRIPTION
[0056] Variations of the devices are best understood from the
detailed description when read in conjunction with the accompanying
drawings. It is emphasized that, according to common practice, the
various features of the drawings may not be to-scale. On the
contrary, the dimensions of the various features may be arbitrarily
expanded or reduced for clarity. The drawings are taken for
illustrative purposes only and are not intended to define or limit
the scope of the claims to that which is shown.
[0057] Various cutting devices and methods for cutting, resecting,
incising or excising tissue are described herein. In certain
variations a cutting device may include a mechanism or motor driven
or powered by a variety of different power sources, e.g., suction
from a vacuum source, pneumatic, fluid pressure (e.g. hydraulic),
compressed air, battery power or electrical power or gas power or
any combination thereof. The mechanism or motor may create a
reciprocating or rotational motion output in any direction which
causes a cutter on or in the cutting device to actuate, e.g.,
reciprocate or rotate, to cut tissue. The cutting device may be
utilized to cut, resect, incise or excise various types of tissue
located in various regions of a patient's body. For example, the
cutting device may be utilized to perform a polypectomy in a
patient for removal of one or more polyps.
[0058] In certain variations, a cutting device powered by suction
from a vacuum source (either external or internal) is provided. The
cutting device may include an elongate shall. The elongate shaft
may have a proximal end, a distal end and one or more lumens
positioned within or along the elongate shaft. The distal end of
the elongate shalt may include an opening or window for receiving
tissue. The device may include a cutter for cutting tissue. A
cutter may be positioned within or on the elongate shall. The
cutter may be actuated, reciprocated, e.g., axially along the
longitudinal axis of the elongate shaft, or rotated to cut tissue.
A chamber may be coupled to the proximal end of the elongate shaft.
The elongate shaft may be coupled to the chamber such that that the
elongate shaft or a cannula remains fixed or immovable relative to
the chamber, e.g., while the cutter, on or in the elongate shall or
cannula, is being reciprocated or otherwise motivated or during
actuation, reciprocation or rotation of the cutter.
[0059] A mechanism or motor may be positioned within the chamber.
The mechanism may be powered by suction created by a vacuum source,
which causes the mechanism to produce a reciprocating motion. In
certain variations, the mechanism may be powered solely by suction
created by the vacuum source, e.g., without the use of electricity
or pressurized air or fluid to power the mechanism. Additional
connections for electrical or pneumatic/hydraulic power may not be
required. The mechanism may include a piston which is put into
reciprocating or reciprocating linear motion by suction from the
vacuum source. The reciprocating motion output produced by the
mechanism causes the cutter (connected to the mechanism) to
actuate, e.g., to reciprocate or to rotate. In certain variations,
the cutter may be reciprocated back and forth in a linear motion,
e.g., axially, or along the longitudinal axis of the elongate
shaft. In other variations, linear reciprocating motion from the
mechanism may be translated into rotational motion of the cutter.
The cutting device may include a port or valve for connecting the
vacuum source to the cutting device to provide suction to the
cutting device.
[0060] The suction from a vacuum source may draw tissue into the
opening in the elongate shaft. The cutter may be reciprocated or
rotated past the opening in the elongate shaft, thereby cutting the
tissue which is drawn into the opening of the elongate shaft. The
cutting device may include an evacuation lumen for evacuating cut
tissue using suction created by the vacuum source. In certain
variations, the tissue may be otherwise removed without using
evacuation to remove the tissue.
[0061] In certain variations, a lumen for delivering irrigant or
fluid may be provided. For example, the elongate shaft may include
a lumen for delivering irrigant to the distal end of an evacuation
lumen in the elongate shaft or to an opening of the elongate shaft
or to a cutter. The irrigant may flow constantly through the lumen,
or it may flow through the lumen only when suction from the vacuum
source is present to draw the irrigant through the irrigant lumen.
The cutting device may include a reservoir lifted with water or
other irrigant positioned with the cutting device or the irrigant
may be provided from an external supply. For example, a syringe
filled with irrigant, e.g., water, may be connected to the cutting
device or an elevated container or bag may supply irrigant to the
cutting device or to the site of treatment. The irrigant may begin
to flow through the cutting device when suction is present in a
lumen within the elongate shaft, at an irrigant port, which may be
located within the shaft lumen near the opening of the elongate
shaft. The irrigant may be drawn to the distal end of an evacuation
lumen in the elongate shaft or to the opening of the elongate
shaft, where it lubricates tissue and a lumen within the shaft,
e.g., a tissue evacuation lumen, to facilitate evacuation of the
cut tissue.
[0062] The cutting device may include a handle, such that the
cutting device may be handheld. For example, the chamber of the
cutting device may be in the form of a handle. The handle may be
positioned or set at an angle relative to the elongate shaft. This
arrangement of the handle or chamber relative to the elongate shaft
may provide a clear or substantially clear line of site above
and/or to the sides of the elongate shaft. The angled arrangement
may reduce interference with other medical devices or instruments
that a user may utilize during a tissue cutting procedure, e.g. an
endoscope and associated cables. This angled arrangement may also
provide optimal user comfort. The handle may have an ergonomic
design to provide comfort and ease of use. A curved or angled neck
portion may extend from the chamber or handle, for receiving or
holding the elongate shaft.
[0063] A tissue collection chamber may be provided. For example, a
tissue collection chamber may be integrated in the chamber or
handle of the cutting device or may be otherwise connected or
attached to the cutting device. The tissue collection chamber may
be removable from the cutting device. The removable tissue
collection chamber may allow tissue collected therein to be
biopsied, studied or a diagnosis of pathology may be performed on
the collected tissue. Removal of the tissue collection chamber
and/or filter may result in the device being disabled, e.g., where
the tissue collection chamber may not be reassembled to the device.
This may prevent the device from being reused or used on more than
one patient to minimize or prevent the associated risks of
transmitting pathogens from one patient to another or infecting
another patient. For example, the device may be disabled where the
internal vacuum lines are sheered when the tissue collection
chamber is removed from the handle. As a result, the tissue
collection chamber cannot be reassembled to the device thereby
rendering the device useless. The device may be fully or partially
disposable.
[0064] In other variations, a tissue collection chamber may be
reusable, where the tissue collection chamber may be removed,
sterilized and then reassembled or reattached to the cutting device
for continued use.
[0065] Various configurations of the elongate shaft are
contemplated. In certain variations, at least a portion of the
elongate shaft or the entire elongate shaft may be malleable or
otherwise adjustable. For example, the distal end of the elongate
shaft or the section of the elongate shaft where tissue cutting is
performed may be malleable or flexible such that portion of the
elongate shaft may be adjusted or manipulated by the user, e.g.,
hand adjustable. The malleable portion of the elongate shall may be
manipulated into a variety of shapes or curves such that the
cutting device, e.g., the cutter or cutter opening, may access or
be positioned in a variety of anatomical locations to cut and/or
remove tissue. The malleable portion of the elongate shaft may be
adjusted or manipulated before or during operation by the user into
various positions or configurations, ranging from, straight to
angled or curved. The shaft may be manually, automatically or
robotically adjusted. The shaft may be adjusted without the need
for additional tools or attachments to change or affect the shape
or position of the shaft, such that the positioning for cutting and
cutting may be performed using a single device. In other
variations, a tool or attachment may optionally be utilized to
adjust or manipulate an elongate shaft for cutting.
[0066] A cutter may have various shapes and configuration, e.g.,
the cutter may be in the form of a cutting blade or pipe or tube
positioned within the elongate shaft. A cutter may be positioned in
the cutting device such that the cutter can reciprocate past an
opening or cutting window in the elongate shall. In certain
variations, the cutter may be positioned within or on the elongate
shall such that the cutting blade is not exposed on an outside of
the opening or window in the elongate shaft or beyond the distal
tip of the elongate shall. This arrangement may provide safety to
patients and minimize or prevent the risk of inadvertently cutting
or puncturing tissue in a patient during the tissue cutting
procedure or during advancement of the cutting device to the target
site in a patient for treatment. In certain variations, the anvil
may protect a cutter such that it is not exposed, thereby providing
safety to patients.
[0067] A sufficient vacuum source for operating or powering any of
the cutting devices described herein may be the vacuum source
provided in most standard operating rooms, physician's offices,
clinics or outpatient surgery centers. For example, many
physicians' offices have vacuum pumps capable of generating vacuum
in the ranges of 10 to 25 inches of mercury (in HG), e.g., about 22
inches of mercury (in Hg) and/or at about 28 to about 40 liters per
minute (LPM) flow rate. The various cutting devices described
herein may utilize vacuum sources or vacuum pumps operating in the
above performance ranges to effectively operate and cut tissue
without additional power inputs or supply requirements needed. For
example, suction provided by such vacuum sources may move, actuate,
reciprocate or otherwise operate the mechanism of a cutting device
and/or the cutter at a speed or rate ranging from about 250 to
about 2500 cycles/min or about 500 to 1200 cycles per minute or
less than about 1200 cycles per minute. These rates are slower than
the rates that would be provided by a typical electrically powered
motor, yet provide the control and power to effectively and safely
operate and reciprocate the cutter of the cutting devices described
herein to cut, resect, and/or excise tissue in various regions in a
patient, e.g., to cut and remove polyps positioned in the nasal or
sinus cavity of a patient in a safe, controlled and effective
manner.
[0068] In certain variations, a cutting device may be connected
solely to a vacuum source, and optionally, to an irrigant source.
The vacuum source may be connected to the cutting device such that
suction supplied by the vacuum source drives or powers the
mechanism of the cutting device, draws tissue into the opening in
the elongate shaft or otherwise into the path of a cutter, draws
irrigant from a reservoir or other source through the cutting
device or through a lumen in or on the cutting device, or to the
cutting device and/or evacuates cut tissue for removal from a
patient.
[0069] Various vacuum powered mechanism for use in the various
cutting devices described herein, to drive or actuate a cutter, are
also described herein. In certain variations, a vacuum powered or
vacuum driven mechanism may include one or more pistons, wherein
suction is applied to both sides of the piston in an alternating
manner to cause the piston to reciprocate. The piston is coupled or
connected (directly or indirectly) to the cutter, thereby causing
the cutter to reciprocate. In another variation, suction may be
applied to one side of the piston and a spring force in a vacuum
powered mechanism may be applied to the other side of the piston,
to cause the piston to reciprocate. The reciprocating piston causes
the cutter to reciprocate.
[0070] In certain variations, a hand-held, fully disposable powered
medical device capable of resecting tissue in the human body is
provided. The device is powered by an internal mechanism that is
powered by suction from an external vacuum source. The mechanism
produces reciprocating motion that may be used to move a cutter
back-and-forth past an opening in a shaft. A portion of the suction
from the external vacuum source is routed through the shaft and
draws tissue into the window where it is excised by the cutter. The
tissue is then evacuated through the shaft and into a tissue
collection chamber on the handle of the device. The suction in the
shaft also draws irrigant into the lumen of the shaft, where it
lubricates the tissue and shaft lumen to facilitate evacuation of
the tissue.
[0071] In certain variations, the cutting devices or mechanisms
described herein may be powered by a vacuum source where the
devices have an efficient use of supplied vacuum suction to the
device, e.g., with none of the supplied suction going unused. In
certain variations, a cutting device may be powered by constant
delivery of vacuum or suction. In certain variations, a cutting
device may be manufactured of all or substantially all mechanical
components reducing costs for manufacturing.
[0072] In certain variations, a cutter may be positioned at or near
the distal end of a flexible shaft that has a preformed or
predetermined curvature. The shaft may be adapted for insertion
into a cannula where the distal end of the shaft may advance from
the cannula toward a target site and where the shaft allows its
predetermined curvature to position the distal end of the shaft
near the target site.
[0073] Exemplary Cutting Devices
[0074] FIG. 1A shows one variation of a vacuum powered cutting
device. Referring to FIGS. 1B-1E, the cutting device 10 includes an
elongate shaft 12. The elongate shaft 12 may include a rigid sleeve
14 that provides rigidity to the elongate shaft. The elongate shaft
may include a window or cutting window or opening 16 positioned at
or near a distal end of the elongate shaft. An evacuation shaft 17
may be positioned within the elongate shaft 12. A cutter 18 may be
positioned within the elongate shaft 12 such that it may be
reciprocated past the opening 16. In this particular variation, the
cutter 18 is formed at the distal end of the evacuation shaft 17,
but other types of cutters are contemplated, e.g., the cutter 18
may extend from a wire or blade positioned in the elongate shaft
12.
[0075] One or more lumens may be positioned within the elongate
shaft 12 (See FIG. 1F). Elongate shaft 12 may include an irrigant
lumen. An irrigant line (not shown) may connect to the proximal end
13 of the elongate shaft 12, to supply irrigant from an internal or
external reservoir or irrigant source, through an irrigant lumen in
the elongate shaft 12, to the distal end of an evacuation lumen in
the elongate shaft or to the opening 16 of the elongate shaft 12.
For example, the irrigant may be drawn to the opening 16 of the
elongate shaft 12, where it lubricates tissue and the evacuation
lumen, to facilitate evacuation of the cut tissue. Optionally, the
elongate shaft 12 may include a malleable portion, for example at
its distal end, which can be manipulated or adjusted to provide
various shapes and configurations to the elongate shaft 12 to
position a cutter in various regions of the body. Optionally, one
or more wires 15 may positioned in the elongate shaft 12, which may
serve to hold the malleable portion of the shaft in a desired
position. A rigid sleeve 14 may be placed over other portions of
the elongate shaft 12 to provide rigidity.
[0076] The elongate shaft 12 may extend from a chamber 20. The
chamber 20 may provide a handle or grip for a user. The chamber 20
may include a tissue collection chamber 22. The evacuation shall 17
may extend into the chamber 20, such that one or more lumens of the
evacuation shaft 17 empties into the tissue collection chamber 22
either directly or indirectly, e.g., via another tube or pipe (not
shown), connecting the evacuation shaft 12 to a first vacuum
chamber port 21. The tissue collection chamber 22 may include a
filter 25 for filtering tissue collected therein. The tissue
collection chamber 22 may be integrated into the chamber 20 such
that removal of the tissue collection chamber 22 disables the
cutting device 10. In certain variations, the elongate shaft 12 may
be coupled or connected to the chamber 20 such that the elongate
shaft 12 remains fixed relative to the chamber 20. For example, the
elongate shaft 12 may be fixed such that it is not motivated or
reciprocated by the mechanism 30 or motor described below.
[0077] A vacuum powered mechanism 30 is positioned within the
chamber 20. FIGS. 2A-2I show various views of the vacuum powered
mechanism 30. The mechanism 30 includes a shuttle piston 32 and a
drive piston 34. The pistons may be arranged in various
configuration, e.g., in parallel to one another. A bi-stable switch
36 may be connected to the shuttle piston 32 and the drive piston
34. The bi-stable switch 36 having a switch spring 37 may be
connected to the drive piston 34 and the shuttle piston 32 either
directly or via a piston clamp 35 connected to the switch spring 37
or bi-stable switch 36. Actuation of the bi-stable switch 36 by the
drive piston 34, which is motivated or reciprocated by suction
created by the vacuum source, may reverse or move the shuttle
piston 32 in either the proximal or distal directions (i.e., toward
the distal end of the cutting device or toward the proximal end of
the cutting device.) When the shuttle piston 32 moves from one end
of its' travel extremity to the opposite end of its' travel
extremity, the evacuated side of a drive piston chamber 42 is
vented to allow atmospheric air to flow into the drive piston
chamber 42 while the opposite side of the drive piston chamber 42
is shut off from atmospheric air and evacuated. As a result, the
drive piston 34 is motivated to move in the opposite direction
until the bi-stable switch 36 is actuated and the shuttle piston 32
reverses. The shuttle piston 32 and the drive piston 34 are
positioned in a manifold 38. The manifold 38 includes a drive
piston chamber 44 and a shuttle piston chamber 42. The bi-stable
switch 36 may ensure a reliable transition of the shuttle piston 32
or valve on the shuttle piston past or completely past a shuttle
chamber vacuum supply port 47 to prevent unstable flutter of the
shuttle piston 32 and possible mechanism 30 or motor stall.
[0078] As shown in the various cross sectional views of FIG. 2B and
FIGS. 2F-2I, at least a portion of the drive piston 34 is
positioned in the drive piston chamber 44 and at least a portion of
the shuttle piston 32 is positioned in shuttle piston chamber 42.
The drive piston chamber 44 and the shuttle piston chamber 42 are
in fluid communication with each other via first and second vacuum
slots 45 and 46.
[0079] A shuttle chamber vacuum supply port 47 is provided to
connect a vacuum source, via a tube or line (not shown), to the
mechanism 30 to provide suction to the mechanism 30. FIG. 1H shows
a vacuum source coupled to a variation of the cutting device 10.
The tube or line may be connected to a second vacuum chamber port
28 (shown in FIGS. 1B-1D) and/or the shuttle chamber vacuum supply
port 47. The shuttle chamber vacuum supply port 47 provides entry
into the shuttle piston chamber 42, such that the vacuum source can
be in fluid communication with the shuttle piston chamber 42 and
evacuate the shuttle piston chamber 42 and/or the drive piston
chamber 44, to power and motivate the drive piston 34 and/or the
shuttle piston 32, as described in further detail herein. Details
of a vacuum powered mechanism are also provided below with
reference to FIGS. 3A-3B.
[0080] The mechanism 30 may be activated and the drive piston 34
reciprocated by suction from the vacuum source as soon as the
vacuum source is connected to the cutting device 10 and the vacuum
source is activated. Referring back to FIGS. 1A-1E, the cutting
device 10 may also include a trigger 26 positioned on the chamber
20 in a location such that the trigger 26 can be conveniently or
ergonomically actuated by a user's finger as the user holds the
cutting device 10. When the trigger 26 is in the "on" position, the
trigger 26 is disengaged from the shuttle piston 32, allowing the
shuttle piston 32 to reciprocate due to motivation of the bi-stable
switch 36 which is in turn motivated by the movement of the drive
piston 34. When the trigger 26 is actuated into an "off" position,
the trigger 26 may interact with or engage the shuttle piston 32,
which causes the shuttle piston 32 and drive piston 34 to stall or
stop such that the cutter 18 is stopped in a position proximal to
the opening 16 thereby leaving the opening 16 open. This allows the
device 10 to be used for suction or evacuation through opening 16,
even when the mechanism 30 and cutter 18 are not activated, as the
vacuum source may remain activated and connected to the cutting
device 10, supplying suction through a lumen of the evacuation
shaft 17. In certain variations, suction may not be supplied
through the lumen of the evacuation shaft during cutting.
[0081] The vacuum source may be connected to the cutting device 10
at the external vacuum port 29. The external vacuum port 29 is in
fluid communication with the tissue collection chamber 22 and the
first vacuum chamber port 21, supplying suction to the lumen of the
evacuation shaft. The external vacuum port 29 is in fluid
communication with the second vacuum chamber port 28, supplying
suction through the shuttle chamber vacuum supply port 47 to the
shuttle piston chamber 42 and the drive piston chamber 44, to
motivate, reciprocate and/or power drive piston 34, which motivates
or reciprocates the bi-stable switch 36 and cutter 18, which is
connected to the vacuum powered mechanism 30 either directly or
indirectly.
[0082] In use, the elongate shaft 12 of the cutting device 10 may
be inserted into the desired location or area in a patient. The
vacuum source is connected to the cutting device 10, supplying
suction to the mechanism 30, causing the drive piston 34 to
reciprocate. The drive piston 34 causes one side of the bi-stable
switch 36 to move either proximally or distally which increases the
tension on the extension spring 37. The increased tension on the
extension spring 37 causes the adjacent side of the bi-stable
switch 36 and the shuttle piston to move proximally or distally to
decrease the length of the extension spring 37. When the seal on
the shuttle piston or shuttle piston 32 moves past the suction port
47, the vacuum or suction in the shuttle chamber 42 reverses to the
opposite side of the drive piston 34 while atmospheric air is
allowed to flow into the side of the shuttle chamber 42 that is not
evacuated, thereby motivating the drive piston 34 to move toward
the evacuated side. (As shown for example in FIG. 2B). The
evacuation shaft 17 is connected to the drive piston 34. The
evacuation shaft 17 may be connected directly to the drive piston
34 or the evacuation shaft 17 may be connected to sleeves, tubes or
other shafts that are connected to the drive piston 34. For
example, the piston clamp 35 may connect the evacuation shaft 17 to
the drive piston 34.
[0083] As stated supra, the cutter 18 is formed at the distal tip
of the evacuation shaft 17. Once the vacuum source is connected to
the cutting device 10 and the trigger 26 is positioned in the "on"
position such that it is disengaged from the shuttle piston 32,
suction applied to the mechanism 30 causes the drive piston 34 (and
consequently the shuttle piston 32 as described above) to
reciprocate, which causes the evacuation shaft 17 and the cutter 18
to reciprocate, driving the cutter 18 back and forth, e.g., in a
linear or axial motion along the longitudinal axis of the elongate
shaft, past the opening 16 in the elongate shaft 12. A close up of
a variation of a cutting window is shown in FIG. 1G. At the same
time, suction may be supplied from the vacuum source through a
lumen of the evacuation shaft 17, to draw tissue into the opening
16, where the tissue is then cut by the reciprocating cutter 18.
Optionally, the suction in the evacuation lumen, may also evacuate
the cut tissue and deliver it to the tissue collection chamber
22.
[0084] While the reciprocating motion of the drive piston 34 of the
mechanism 30 is translated to the cutter 18 via the evacuation
shaft 17 in the variation described above, other components for
translating such reciprocating motion are also contemplated. For
example a cutter may extend from a wire or blade or any other
extension or member which is connected to the mechanism 30, e.g.,
via the drive piston 34 or piston claim 35. In certain variations,
the cutter 18 may be directly or indirectly connected to the
mechanism 30 or the drive piston 34 or the shuttle piston 32 or the
bi-stable switch 36.
[0085] In certain variations, a loop or extension may be provided
in the evacuation shalt 17 or in a tube or pipe connecting the
evacuation shaft 17 to the first vacuum chamber port 21, providing
extra length that may move or change shape such that at least a
portion of the evacuation shaft 17 or tube or pipe that is
connected to the first vacuum chamber port 21 does not move or
reciprocate or become dislodged when the evacuation shaft 17 is
being reciprocated or motivated by the mechanism 30.
[0086] In certain variations, a method of cutting and removing
tissue from a subject may include advancing a cutting device at,
next to, in or near a target tissue in the subject. The cutting
device may include an elongate shaft and a cutter positioned within
or on the elongate shaft. The elongate shaft may be advanced into
the subject to access the target tissue and to position the cutter
at, next to, in or near the target tissue to cut and/or remove the
tissue. The cutting device includes a mechanism or motor which is
powered or driven by suction created by a vacuum source. The
suction from the vacuum source powers the mechanism causing it to
produce a reciprocating or rotating motion which causes the cutter
to reciprocate or rotate to cut tissue. The tissue may optionally
be evacuated using suction created by the vacuum source. The cut
tissue may optionally be gathered or collected with the cutting
device. In certain variations, suction or vacuum may be turned off
or not supplied to the opening and the tissue may be otherwise
removed. In certain variations, the suction from the vacuum source
may draw tissue into an opening on the elongate shaft. The cutter
may be reciprocated or rotated past the opening to cut the tissue
drawn into the opening on the elongate shaft. In certain variations
suction from the vacuum source may draw an irrigant to the distal
end of an evacuation lumen in the elongate shaft or to the opening
of the elongate shaft, where it lubricates tissue and/or the
evacuation lumen, to facilitate evacuation of the cut tissue. In
certain variations, the cutting device may include a chamber in
which the mechanism is positioned. The elongate shall may be
attached to the chamber such that it remains in a fixed position
relative to the chamber while the mechanism is producing a
reciprocating motion and reciprocating a cutter shaft or evacuation
shaft positioned within the elongate shall.
[0087] In certain variations, a method of cutting, resecting or
excising tissue in a patient may include attaching the cutting
device to a vacuum source (internal or external) and optionally to
a source of irrigant. The vacuum source supplies suction that may
power or motivate the mechanism or motor of the cutting device,
draw tissue into the path of a cutter or cutting blade, draw
irrigant from an irrigant source to the site of cutting or excision
or near the cutter, and/or evacuate cut tissue from the
patient.
[0088] In certain variations, a method for performing a polypectomy
in a subject may include advancing a cutting device at, to, next
to, in or near a target polyp. Polyps may be located in various
regions of a patient. For example, nasal or sinus polyps may be cut
and/or removed by advancing the cutting device into the nasal
cavity and positioning a cutter at, next to, in or near the polyp.
The cutting device may include an elongate shaft and a cutter
positioned within or on the elongate shaft. The elongate shaft of
the cutting device may be advanced into the nasal or sinus cavity
to access the polyp and position the cutter near the polyp. The
cutting device includes a mechanism or motor which is powered by
suction created by a vacuum source. The suction from the vacuum
source powers the mechanism causing it to produce a reciprocating
or rotating motion which causes the cutter to reciprocate or rotate
to cut tissue. The tissue may optionally be evacuated using suction
created by the vacuum source. The cut tissue may optionally be
gathered or collected with the cutting device. In certain
variations, suction or vacuum may be turned off or not supplied to
the opening and the tissue may be otherwise removed. In certain
variations, the suction from the vacuum source may draw tissue into
an opening on the elongate shaft. The cutter may be reciprocated
past the opening to cut the polyp tissue drawn into the opening on
the elongate shall. In certain variations, the mechanism may be
powered solely by suction from a vacuum source, without requiring
the use of compressed or pressurized air or electric power to
supply power.
[0089] In certain variations, a method for performing a discectomy
in a subject may include advancing a cutting device at, to, next
to, in or near a disc in a spine. For example, a disc annulus or
nucleus may be cut by advancing the cutting device into or next to
the disc and positioning a cutter at, next to, in or near the disc.
The cutting device may include an elongate shaft and a cutter
positioned within or on the elongate shaft. The elongate shaft of
the cutting device may be advanced into or next to the disc to
position the cutter. The cutting device includes a mechanism or
motor which is powered by suction created by a vacuum source. The
suction from the vacuum source powers the mechanism causing it to
produce a reciprocating or rotating motion which causes the cutter
to reciprocate or rotate to cut tissue. The tissue may optionally
be evacuated using suction created by the vacuum source. The cut
tissue may optionally be gathered or collected with the cutting
device. In certain variations, suction or vacuum may be turned off
or not supplied to the opening and the tissue may be otherwise
removed. In certain variations, the suction from the vacuum source
may draw tissue into an opening on the elongate shall. The cutter
may be reciprocated past the opening to cut the disc tissue drawn
into the opening on the elongate shaft. In certain variations, the
mechanism may be powered solely by suction from a vacuum source,
without requiring the use of compressed or pressurized air or
electric power to supply power.
[0090] In certain variations, a user may cut tissue by positioning
a cutting window on an elongate shaft against the tissue to be
resected and actuate a switch or trigger to allow the mechanism to
reciprocate. This causes a cutting blade to move back-and-forth
past the cutting window. As tissue is drawn into the cutting window
by suction, the blade shaves the portion of tissue that is in the
path of the cutting blade. The tissue is then evacuated through the
lumen of the shaft that is connected to the blade and is deposited
in a tissue collection chamber.
[0091] The cutting devices described herein may be utilizing for a
variety of procedures as described supra. The cutting device may be
advanced or inserted into or through existing orifices, cavities or
passages, e.g., a nasal cavity, airway, respiratory passage,
reproductive pathways, intestinal pathways or other pathways. The
cutting devices may be advanced or inserted into a patient
percutaneously, intraluminally or in any minimally invasive manner
to perform a procedure in or on a subject. Optionally, a cutting
device may be utilized through a surgical incision or site.
[0092] The various cutting devices described herein, e.g., a
handheld and/or portable cutting device, allow for cutting and/or
removal of tissue, e.g., a nasal polyp, by providing a low cost,
disposable device that allows the tissue cutting procedure to take
place in a manner that is safe, quick, and inexpensive. The cutting
device does not require significant setup time, or the
inconvenience and expense associated with capital equipment.
In-office tissue removal using a cutting device may be performed
using local anesthetic as compared to general anesthetic which is
used in ambulatory surgery centers. For example, a cutting device
may be utilized to perform nasal and sinus polyp removal in a
doctor's office setting. While the cutting devices described herein
may be used to perform a polypectomy, they can also be used for
tissue resection procedures in other locations of the body, e.g.,
including for ear, nose, and throat surgery, gynecological surgery,
spinal surgery, general surgery and ophthalmic surgery.
[0093] A cutting device that uses a vacuum source, e.g., an
external vacuum source, to power an actuating or reciprocating
mechanism or motor that is connected to a cutter, thereby
translating the reciprocating motion to the cutter to cause the
cutter to reciprocate provides a number of advantages and
efficiencies. The cutting device does not require an investment in
capital equipment, such as electric powered consoles, thus
providing a user with a substantial cost savings. Capital equipment
requires valuable storage space when not in use as well as service
and maintenance in the facilities where it is used. The cutting
device also allows a manufacturer to make continuous improvements
without being constrained by installed capital equipment.
[0094] The cutting devices described herein may be manufactured
using low cost components and assembly techniques, making the cost
of the device much lower than a cutting device which utilizes an
electric motor. The elongate shaft may be constructed from a
variety of materials. For example, a combination of metal and
plastic components that are not susceptible to heat buildup
resulting from friction between moving components may be
utilized.
[0095] Using a vacuum source as the power source to provide both
tissue evacuation and mechanical motion to cut tissue eliminates or
reduces the number of additional or separate connections, wires or
tubes that would otherwise be required to provide electrical or
other pneumatic power, such as pressurized or compressed air, and
evacuation. A standalone console to transfer the electrical or
other pneumatic power may not be required to operate the cutting
device.
[0096] In certain variations, a single tube connects the vacuum
source to the cutting device to serve the functions of tissue
cutting, evacuation, and to power the mechanism which actuates the
reciprocating cutter. A single tube simplifies connections required
for device operation and reduces the number of tubes attached to
the device thereby reducing the "clutter" and unwieldiness caused
by multiple tubes and wire connections extending from a device.
[0097] In certain variations, a splitting connection within the
handle may be provided which connects the vacuum to both a tissue
evacuation tube and the vacuum powered mechanism. The splitting
connection may come in multiple forms such as multiple connections
to the tissue collection chamber where a single connection to a
source of vacuum creates a vacuum within a Filter Chamber. Another
form of a splitting connection may be a "Y" or "T" shaped junction
that joins two fluid paths into a single path. As a result of
sharing the vacuum source between the mechanism and the evacuation
tube and cutting window or opening, the vacuum perform several
functions within the device: powers the mechanism which causes the
cutter to reciprocate, draws tissue into an opening or cutting
window such that it may be excised, evacuates the excised tissue
through the tissue evacuation shall to a filter or tissue
collection chamber.
[0098] Where an external vacuum source is connected to the device
to provide suction to facilitate tissue cutting and evacuation, an
additional power source such as electricity, compressed air, or
mechanical input by the operator may not be required.
[0099] Using vacuum power to actuate the cutter reduces operator
fatigue compared to a system requiring the operator to manually
actuate the reciprocating mechanism. The rate at which the cutter
actuates, relative to manual actuation, may be significantly
increased, thereby reducing the time required to complete a tissue
resection or excision procedure. Also, the control for the rate of
actuation of the mechanism or motor may be moved from a "primary"
position, such as a trigger or button, to a "secondary" position,
e.g., on the device handle. As a result, the "primary control" may
be utilized to control other parameters, e.g., the rate at which
the cutter actuates, the radius of curvature of the elongate shaft,
or to control an electrocautery system that may be included in or
on the device. A knob, trigger, roller clamp, or other control
interfaces may be used to control the rate at which the vacuum
driven mechanism or motor actuates or reciprocates. These options
allow the device to be designed in a variety of configurations to
suit various surgical specialties or personal preferences.
[0100] The cutting devices described herein may have a relatively
low mass, providing ease of use and comfort during short or long
procedures. The cutting devices may be easily sterilized using
commonly used sterilization techniques such as electron beam
radiation, gamma radiation, or Ethylene Oxide gas.
[0101] In certain variations, a pneumatic logic sequence that
maintains high vacuum throughout the mechanism, motor or engine
cycle by never venting the vacuum source to the atmosphere may be
provided. As a result, the vacuum suction or pressure that
facilitates cutting and evacuation does not decrease while the
mechanism or motor reciprocates.
[0102] In certain variations, the cutting device may include
cautery, e.g., an electrocautery system or wires heated via
monopolar or bipolar radiofrequency, or by resistive heating. The
cautery may be located at or near the distal extremity of the
device to cauterize tissue to control bleeding at the site where
tissue has been cut or excised. Having a cautery obviates the need
to remove the device from an operative site and replace it with a
separate electrocautery device, thereby improving speed and
ease-of-use for the operator while reducing blood loss for the
patient. The electrocautery system may be powered by wires that run
the length of the elongate shaft through an internal lumen within
the elongate shaft. The wires may be connected to a power console
or optionally the power source may be located in the handle or
chamber of the cutting device.
[0103] In certain variations, a resistive heating electrocautery
system may be provided on the distal tip of an elongate shaft. The
power source for the electrocautery system may be located in the
handle of the cutting device and may be connected to the distal tip
of the shaft by wires that run the length of the shaft. The power
source may include one or more batteries that provide electrical
energy to the distal end of the device. The electrical energy may
be converted to heat energy when passed through a heating element
such as a tungsten wire.
[0104] As described supra, in certain variations, a cutting device
may include a malleable elongate shaft or at least a partially
malleable elongate shall that that may be hand adjustable. A
flexible or malleable shaft provides access to multiple anatomical
locations using a single device, thereby improving cost efficiency
and convenience for the operator. One or more annealed wires may be
positioned in an elongate shaft or flexible shaft to allow the
shaft to be manually shaped by the user intra-operatively.
Alternatively, malleable tubing may be used to construct the
elongate shaft to allow manual shaping of the shaft. Additionally,
when the distal end of the elongate shaft is curved toward the
cutting window, visibility of the cutting window location is
improved.
[0105] In certain variations, the elongate shaft may be flexible
and a semi-rigid or rigid outer cannula or sheath may be provided
on the shaft to change the radius of curvature on the shaft in a
range from substantially straight to curved, in an arc of about 180
degrees. The cannula allows the operator to optimize the curvature
of the shaft based on the patient anatomy. The operator may also
increase or decrease the force between the elongate shall or cutter
and the target tissue being cut by extending or retracting the
cannula to increase or decrease the natural radius of curvature of
the elongate shaft.
[0106] In certain variations, a semi-rigid or rigid outer sheath or
cannula positioned over a flexible curved elongate shall may be
used to change the radius of curvature of the curved shall. The
radius of curvature may increase when the straight and rigid sheath
is extended over the curved portion of the shaft, whereas the
radius of curvature returns to its precurved or predetermined shape
when retracted from the curved portion of the shaft.
[0107] The radius of curvature of a flexible curved elongate shaft
may be altered in-vivo by utilizing or advancing or retracting a
cannula over the elongate shall. This allows the operator to change
the radius of curvature of the elongate shaft in situ to gain
access to a variety of anatomical locations without removing the
device or elongate shaft from the operative site to change the
radius of curvature.
[0108] In certain variations, the distal tip of the elongate shaft
may be rounded and less likely to perforate sensitive structures or
other tissue during advancement to a target tissue or while cutting
is being performed. This reduces susceptibility to inadvertent
contact with tissues that may result in unintended injury to the
patient.
[0109] Reciprocating a cutter in a back-and-forth motion may shave
and cut tissue by scissoring it rather than grabbing and ripping
tissue as may be the case with certain rotary cutters or rotary
mechanisms or motors. Back-and-forth cutting action may shave
tissue with less movement of the tissue, which reduces the tension
on the tissue and consequent trauma to the tissue thereby reducing
the likelihood of bleeding. The excised tissue may then be
evacuated through an evacuation shaft and into a tissue collection
chamber.
[0110] An elongate shaft that includes a cutter shaft or an
evacuation shall with a cutter at its distal end, which may be
reciprocated in a back and forth motion along the longitudinal axis
of the elongate shaft, may be positioned in line or at an angle
relative to the vacuum driven mechanism or motor and the handle or
chamber in which the mechanism or motor is positioned. Positioning
at an angle allows the device handle to be positioned away from the
control surfaces, light cord, and any power cables for an endoscope
and/or camera that may also be used during the tissue cutting
procedure. The operator's ease-of-use is improved because the
endoscope and the cutting device are not interfering with one
another.
[0111] A cutting device having a handle or hand piece that may be
positioned in line with an elongate shaft or at an angle to the
longitudinal axis of the elongate shaft may provide improved
ergonomic features for the operator. For example, when the operator
is using a second device, (e.g., an endoscope as described supra)
through the same orifice or port that the elongate shall of the
cutting device has entered, the two devices may interfere with one
another. However, by positioning the handle or hand piece at an
angle to the longitudinal axis of the shaft, the top and sides of
the cutting device around the shaft and the connection between the
handle and the shaft are at a very low profile. Thus, the
likelihood of interference is reduced. In certain variations, the
elongate shaft may be actuatable, such that the elongate shaft may
be moved between a position in line with a handle or at an angle to
a handle.
[0112] The back and forth reciprocating motion of a cutter shaft or
an evacuation shaft with a cutter blade at its distal end may be
translated along a nonlinear path. Therefore, it is possible to
position the vacuum driven mechanism or motor at an angle relative
to elongate shaft of the device. Furthermore, the back and forth
reciprocating motion of the cutter shaft or an evacuation shaft
allows the elongate shaft of the cutting device to be bent at the
distal portion of the shaft (e.g., where the shaft is malleable) to
allow it to be shaped to access a variety of locations in the
anatomy.
[0113] In certain variations, separate conduits may be provided
between the mechanism and evacuation lumen such that vacuum for
evacuating tissue is not interrupted by the mechanism function.
[0114] An anvil component may be located at the distal end of the
elongate shaft. An extension (e.g., a "tail") of the anvil may be
provided proximal to the cutting window. The extension may improve
flexibility of the shaft allowing the shaft to be malleable closer
to the distal end of the shaft. The anvil and/or extension may
maintain or provide a guide for the evacuation shalt or the cutter
shaft as it translates or reciprocates axially. In the absence of
an extension, a longer anvil component that may be rigid over its
entire length or a portion of its length may be provided.
[0115] In certain variations, a cutting opening or window may be
positioned on the side of the elongate shaft. The side positioning
allows the operator to maintain visual contact or visualization on
the position of the opening or window and tissue that comes into
contact with the opening or window. This visual contact reduces the
likelihood of unintentionally causing injury to tissue.
[0116] A cutting window may be shaped to prevent the cutter from
exiting the lumen of the elongate shaft or the anvil component,
through the cutting window. The cutting window in combination with
the cutter may provide a tissue scissoring cutting action, as
compared to a guillotine cutting action on a straight sided cutting
window.
[0117] In certain variations, the distal portion of an elongate
shall may be plastic, an indwelling anvil component may be metal, a
cutter may be metal and the evacuation tube may be plastic. This
arrangement may reduce the likelihood of heat build up from
friction between moving and/or stationary components of the cutting
device. This arrangement may create a scissoring cutting action,
and/or allow the distal end of the elongate shaft to be flexible
and malleable. Additionally, the use of plastic components reduces
or eliminates the possibility that electrical energy may be
unintentionally transmitted through the shaft thereby injuring the
patient.
[0118] Optionally, the elongate shaft may be rotatable about the
axis of the shaft relative to the device handle or chamber, which
allows the operator to rotate the shaft without rotating the device
handle.
[0119] In certain variations, one or more lumens 51, e.g.,
nonconcentric lumens may be positioned in the elongate shaft (As
shown in FIG. 1F). Nonconcentric lumens may provide advantages
compared to single lumen shafts and shafts having concentric
lumens. For example, one or more of the lumens may be used for the
following purposes: to provide a fluid conduit for irrigant; to
hold or contain one or more malleable wire(s) to maintain the shaft
curvature when shaped by the operator; to contain the evacuation
shaft or cutter shaft and evacuation lumen; and/or to transmit
fluid to treat bleeding.
[0120] In certain, variations, an evacuation lumen may be non
contiguous around its circumference down a portion or the entire
length of the evacuation shaft to improve flexibility while
reducing the likelihood of kinking the evacuation lumen.
[0121] A small gap or a sealing O-ring between the evacuation shaft
and the inside of the main lumen of the elongate shaft, may reduce
the likelihood of leakage of suction through the proximal end of
the elongate shaft, which would reduce the suction present at the
window.
[0122] Optionally, a ring of material may be provided between the
outside diameter of a noncontiguous evacuation lumen and the inside
diameter of a multi-lumen evacuation shaft or tubing that seals the
air gap between the two structures and thereby reduces leakage of
air flow in the distal direction from the device handle to the
opening in the evacuation shaft or lumen, located proximal to the
cutting window or opening.
[0123] Optionally, various fluids may be applied or delivered to
the distal end of the elongate shaft where the cutter and window
are positioned. A fluid may be emitted, via a lumen in the elongate
shaft, from the distal end of an elongate shaft at a temperature
that is low enough such that the fluid can be used as a bleeding
therapy. A collagen foam may be emitted from the distal end of the
elongate shaft as a bleeding therapy. These are inexpensive, quick,
and easy ways to apply a bleeding therapy or anticoagulant to a
bleeding site where tissue is being cut. Anti-coagulant substances
emitted from the distal end of the elongate shaft as a bleeding
therapy may be applied directly and conveniently to the tissue,
e.g., without exchanging or removing the cutting device to replace
it with a separate device intended for applying anticoagulation
therapy.
[0124] In certain variations, separate fluid conduit paths to the
vacuum source may be provided to allow the vacuum powered mechanism
and cutter to be operated independently from the tissue evacuation.
The independent fluid paths and operation capability of the vacuum
powered mechanism and evacuation may allow the opening in the
distal end of the elongate shaft of the cutting device to operate
as a suction port to evacuate tissue and blood even when the vacuum
powered mechanism is not in operation or is stalled or halted,
e.g., when the trigger is actuated to engage and hold the shuttle
piston to prevent its reciprocation.
[0125] Optionally, a single fluid conduit path between a cutting
window and the vacuum source that includes an evacuation shaft and
vacuum mechanism may be utilized to reduce the air flow
requirements of the device by using air flow created by the vacuum
to power both the vacuum mechanism and the evacuation of
tissue.
[0126] Set forth below are additional features or functions that
may be utilized or included with various cutting devices described
herein:
[0127] A clear tissue collection chamber may be utilized to allow
the operator to intraoperatively visualize resected tissue in real
time. Additionally, the operator and patient are able to see
whether the device has been previously used by inspecting the
tissue collection chamber.
[0128] A dual chamber tissue collection system may be provided to
separate tissue resected from different locations in the event it
is desired to biopsy the tissue from two different locations in the
body.
[0129] A bi-stable switch fabricated from plastic, metal or other
material and an elastic spring may be utilized in a mechanism to
ensure reliable transition of a Shuttle piston past a vacuum supply
port to prevent unstable flutter of the Shuttle piston and
consequent mechanism or motor stall. Optionally, a bi-stable switch
fabricated using sheet metal with two legs that are connected at
one end but separated at the opposite end in their natural state
may be provided. The separate sheet metal legs are then riveted or
otherwise connected to create a bowed sheet metal component that is
stressed and bi-stable. Optionally, the separated end may be folded
and joined to result in a three dimensional curve that is stable in
two positions. These variations may not require a separate elastic
spring to be bi-stable.
[0130] Optionally, back-and-forth reciprocating motion from a
vacuum powered mechanism may be mechanically converted to
rotational motion or rotary oscillation to provide rotational or
rotary oscillation mechanical output by the mechanism.
[0131] A tissue evacuation shaft may be routed through the center
of the drive Piston to provide an efficient method of transferring
the mechanical output of the mechanism to the cutter at the
window.
[0132] To prevent vacuum leakage in the motor, a thin plastic seal
may be molded integral to a component and plastically deformed by
squeezing the thin plastic seal in a die to increase its
flexibility and conformability. This may reduce the cost of
components and assembly labor, and it may improve the overall
reliability of the mechanism. Optionally, flash formed at a parting
line of a mold may be used as a seal because it is very thin and
flexible and conforms to the geometry of mating components while
maintaining minimal friction between components. An O-ring may
optionally be used to create a seal between molded components.
[0133] In certain variations, a mechanism may include a Shuttle
piston positioned or arranged adjacent to and/or parallel to the
drive Piston such that overall mechanism and or device size is
reduced, the transfer of mechanical motion between the pistons is
easier and more efficient and the flow of air through the device is
more efficient. This arrangement may allow for a smaller, easy to
hold and use device. The shuttle and drive piston's may be coupled
by a bi-stable switch.
[0134] A spring-loaded Trigger may directly or indirectly interact
with the Shuttle piston or valve to turn the mechanism "ON" and
"OFF." This reliably and consistently controls the mechanism
function. The trigger may be designed to always stop the motor with
the Cutter shaft proximal to the opening or cutting window thereby
leaving the cutting window open such that the device may be used in
"suction only" mode through the window. Additionally, a device
cleaning tool, such as a declogger, may be threaded through the
cutting window and proximally advanced through and/or along the
tissue evacuation path to clear or remove obstructions in the
tissue evacuation path.
[0135] A loop of flexible tubing that connects the evacuation shaft
to a stationary connection on the device, such as a vacuum port,
provides a low cost way to allow back-and-forth motion of the
evacuation shaft and the mechanism without causing shaking,
vibration or external motion of other tubing or components in a
chamber or handle, and without dislodging the evacuation path
connection to the tissue collection chamber. The loop of tubing may
change shape to accommodate the back-and-forth motion of the
evacuation shaft.
[0136] The cutting device may be designed such that irrigant does
not flow unless suction is present at the opening or cutting window
to draw the irrigant, e.g., to provide a self regulating supply of
irrigant. This may be possible by supplying a reservoir of irrigant
that is not pressurized relative to atmospheric air, however, when
suction is applied to the reservoir, irrigant flows from the
reservoir and toward the source of vacuum. An example of this is a
syringe filled with irrigant that is connected to tubing; when
suction is applied to the tubing, irrigant flows from the syringe
and through the tubing toward the source of vacuum. This will
ensure the irrigant does not unintentionally flow out of the device
and leak into the patient where it may be problematic such as when
aspirated by the patient (e.g., when the device is used in the
respiratory passages), e.g., where a patient is under general
anesthesia and can't communicate. An irrigant reservoir may be
located within the handle of the device such that it may be filled
by the operator as needed, thereby reducing the number of tubes and
connections that are tethered to the cutting device.
[0137] A cutting device or microdebrider having a reciprocating or
hack-and-forth cutting motion may optionally be powered by an
integrated supply of compressed air such as a CO2 cartridge or by a
battery, e.g., one that supplies electricity to a DC motor that
actuates a cutter. This would allow the vacuum supply to be used
entirely to draw tissue into the cutting window and to evacuate
excised tissue thereby increasing or improving a resection rate. A
separate power console is not necessary to provide power to the
device.
[0138] Exemplary Vacuum Powered Mechanisms or Motors
[0139] A vacuum powered or driven mechanism or motor used in
various of the cutting devices described herein may be so called
because it uses suction from an internal or external vacuum source
to produce movement. The vacuum mechanism or motor does not create
suction and is not to be confused with a vacuum pump. The Vacuum is
used to power a mechanism to power a medical device which cuts and
evacuates tissue. A vacuum-powered mechanism generates the
reciprocating or rotating motion of the cutter in the device. The
mechanism may be powered by the difference in ambient atmospheric
air pressure on one side of a piston and a vacuum (or partial
vacuum) on the opposite side of the piston in the chamber or
cylinder in which the piston is positioned.
[0140] One vacuum mechanism or motor described herein may be
referred to as a double action vacuum powered mechanism or double
action mechanism because it uses suction to move the piston in both
directions. Vacuum or suction is alternately applied to either
sides of a piston to cause the piston to alternately move back and
forth in the direction of the vacuum (or partial vacuum). Vacuum
mechanisms or motors that use a spring to return them to their
starting position may be referred to as a spring action or spring
return mechanism. A single action mechanism or motor may use a
vacuum to drive the piston in a single direction until the vacuum
is vented and the piston is returned to its starting position by a
spring.
[0141] One advantage of using vacuum to move the piston in both
directions, as compared to using a spring to return the piston to
its starting position, is that the efficiency of the motor is
nearly doubled. A spring return mechanism must have a piston size
and cylinder volume that is large enough to generate adequate force
both to perform the work output required of the motor as well as to
compress the return spring. The smaller piston size of a double
action mechanism allows the mechanism to be incorporated into a
handheld device. The spring on a spring-return motor must be
adequately sized to reliably return the piston to its starling
position with an adequate safety margin to reliably overcome
friction and external forces on the mechanism.
[0142] Exemplary variations of vacuum driven mechanisms are
described herein. FIGS. 3A-5B show various mechanisms in distal and
proximal positions. The distal position refers to a piston in the
mechanism being motivated in a direction toward the distal end of
the cutting device in which the mechanism would be situated.
Regarding the figures described below, from a viewer's perspective,
the left side of the figures is the proximal side and the right
side of the figures is the distal side. The proximal position
refers to a piston in the mechanism being motivated in a direction
toward the proximal end of the cutting device in which the
mechanism would be situated.
[0143] FIG. 3A shows a cross sectional view of a variation of a
double action vacuum powered mechanism 310 or motor, similar to the
mechanism 30, referred to above. The mechanism 310 includes a
bi-stable switch. FIG. 3A shows the mechanism 10 in a proximal
position, while FIG. 3B shows the double action vacuum powered
mechanism in the distal position.
[0144] Referring to FIGS. 3A-3B, the vacuum powered mechanism 310
includes a drive piston 301 having a piston shaft 302. The drive
piston 301 including at least a portion of the piston shaft 302 are
positioned within a drive piston chamber 307. The drive piston 301
divides or separates the drive piston chamber into a proximal drive
piston chamber 307a and a distal drive piston chamber 307b. The
drive piston 301 may reciprocate proximally and distally within the
drive piston chamber 307 when vacuum and ambient air are
alternately applied to opposite sides of the drive piston 1 in
drive piston chambers 307a and/or 307b. The piston shaft 302 may
reciprocate along with the drive piston 301, and the reciprocating
piston shaft 302 may conduct reciprocating motion output.
[0145] A bi-stable switch 303 is connected or coupled to a shuttle
piston 314 and a switch spring 305. The switch spring 305 may cause
the bi-stable switch 303 to quickly transition from a distal
position to a proximal position and vice versa. The bi-stable
switch is stable when it is in either a proximal position (FIG. 3A)
or a distal position (FIG. 3B), but not when it is in between those
two positions and therefore the switch resists residence in an
in-between state. As a result, the mechanism does not "flutter" or
the mechanism minimizes "flutter" when in transition between
states. For example, the shuttle valve 313 may not flutter or not
fail to fully transition from a proximal to a distal position or
vice versa as the bi-stable switch causes the shuttle piston 314
and a shuttle valve 313 to transition or translate in the proximal
or distal direction over and past a shuttle chamber vacuum supply
port 308.
[0146] The bi-stable switch 303 may be actuated by the drive piston
shaft 302 when the drive piston 1, and therefore the piston shaft
302, move in either the proximal or distal directions. Actuation of
the bi-stable switch 303 results in movement of the shuttle piston
314 in either the proximal or distal directions. Movement of the
drive piston in the proximal direction results in movement of the
shuttle piston in the proximal direction via the bi-stable switch,
while movement of the drive piston in the distal direction results
in movement of the shuttle piston in the distal direction via the
bi-stable switch.
[0147] The shuttle piston 314 is positioned within a shuttle piston
chamber. The shuttle piston 314 includes a shuttle valve 313 or
flange which may extend radially therefrom, which separates or
divides the shuttle piston chamber into a proximal shuttle piston
chamber 315 and a distal shuttle piston chamber 316. Proximal
shuttle piston chamber 315 may be in fluid communication with
proximal drive piston chamber 307a via proximal vacuum slot 304.
Distal shuttle piston chamber 316 may be in fluid communication
with distal drive piston chamber 307b via distal vacuum slot
306.
[0148] The shuttle piston (314) may also include a proximal ambient
air seal (309), a proximal cruciform (310), a distal ambient air
seal (311), a distal cruciform (312), and a central shaft
connecting the above components.
[0149] A shuttle piston chamber vacuum supply port (308) may be
connected to an external or internal vacuum source or supply to
evacuate the proximal shuttle piston chamber 315 and/or the distal
shuttle piston chamber 316. The vacuum port 308 may allow for
evacuation by vacuum of the proximal drive piston chamber 307a via
the proximal vacuum slot 304 and the proximal shuttle piston
chamber 315. The vacuum port 308 may allow for evacuation by vacuum
of the distal drive piston chamber 307b via the distal vacuum slot
306 and the distal shuttle piston chamber 316.
[0150] For example, Proximal drive piston Chamber (307a) may be
evacuated by vacuum when in fluid communication with the external
vacuum source via the Vacuum Port (308), Proximal Shuttle piston
Chamber (315), and proximal vacuum slot 304. Distal drive piston
Chamber (307b) may be evacuated by vacuum when in communication
with the external vacuum source via the Vacuum Port (308), Distal
Shuttle piston Chamber (316), and distal vacuum slot 306. Presence
of vacuum in Proximal drive piston Chamber 307a results in
differential pressure between the proximal and distal sides of the
Piston (301) that results in working force to move the Piston (301)
proximally when ambient air is in the distal drive Piston Chamber
(307b). Alternately, ambient air (322) in proximal drive piston
Chamber 307a applies working force to move the Piston (301)
distally when the Distal drive piston Chamber (307b) is
evacuated.
[0151] The shuttle piston 314 may be translated or positioned in a
shuttle piston chamber such that Shuttle piston valve 313 can seal
against the shuttle block (321) to the distal side of the vacuum
port (308) to allow the proximal shuttle piston chamber (315)
and/or proximal drive piston chamber (307a) to be evacuated by
communicating with an external vacuum supply. Alternatively, the
shuttle piston 314 may be translated or positioned in a shuttle
piston chamber such that the shuttle piston valve 313 may seal
against the shuttle block (321) to the proximal side of the vacuum
port (308) to allow the distal shuttle piston chamber (316) and/or
distal drive piston chamber (307b) to be evacuated by communicating
with the external vacuum supply.
[0152] The proximal shuttle piston chamber (315) may allow for
fluid communication between the Vacuum Port (308) and the Proximal
drive piston Chamber (307a) through the Proximal Vacuum Slot (304).
The proximal shuttle piston chamber (3315) may also allow for fluid
communication between the Proximal drive piston Chamber 307a and
ambient air when the Proximal Shuttle Seal (309) is in the proximal
position, i.e., an open or unsealed position.
[0153] The Distal Shuttle piston Chamber (316) may allow for fluid
communication between the Vacuum Port (308) and the Distal drive
piston Chamber (307b) through the Distal Vacuum Slot (306). The
Distal Shuttle piston Chamber (316) may allow for fluid
communication between the Distal drive piston Chamber 307b and
ambient air when the Distal Shuttle Seal 311 is in the distal
position, i.e., an open or unsealed position.
[0154] The proximal ambient air seal (309) of the shuttle piston
314 may seal against shuttle block (321) to prevent ambient air
leakage into proximal shuttle piston chamber 315 when the proximal
shuttle piston chamber (315) is evacuated. Also, the proximal
cruciform (310) can maintain shuttle piston (314) position
concentricity relative to proximal shuttle piston chamber (315),
e.g., when the shuttle piston (314) moves to a proximal position
and vents ambient air to the proximal shuttle piston chamber
(315).
[0155] The distal ambient air seal (311) of the shuttle piston 314
may seal against shuttle block (321) to prevent ambient air leakage
into distal shuttle piston chamber 316 when the distal shuttle
piston chamber (316) is evacuated. Also, the distal cruciform (312)
can maintain shuttle piston (314) position concentricity relative
to distal shuttle piston chamber (316), e.g., when the shuttle
piston (314) moves to a distal position and vents ambient air to
the distal shuttle piston chamber (316).
[0156] The vacuum powered mechanism 310 may also include a Distal
drive piston chamber Endcap (317), which may prevent or minimize
fluid communication between ambient air and the Distal drive piston
Chamber (307b) in addition to providing a sealing and bearing
surface with the drive Piston Shall (302). The vacuum powered
mechanism 310 may also include a Distal drive piston chamber Endcap
Seal (318), which may prevent or minimize ambient air leakage
between the Distal drive piston chamber Endcap (317) and the drive
piston Shaft (302), e.g., when the Distal drive piston Chamber
(307b) is evacuated.
[0157] The vacuum powered mechanism 310 may also include a Proximal
drive piston Chamber Endcap (319), which may prevent or minimize
fluid communication between ambient air and the Proximal drive
piston Chamber (37a) in addition to providing a sealing and bearing
surface with the drive Piston Shaft (302). The vacuum powered
mechanism or motor 310 may also include a Proximal drive piston
Chamber Endcap Seal (320), which may prevent or minimize ambient
air leakage between the Proximal drive piston Chamber Endcap (319)
and the drive Piston Shaft (302), e.g., when the Proximal drive
piston Chamber (307a) is evacuated.
[0158] The drive piston shaft 302 may seal against the endplates or
endcaps 317, 319 or shuttle block 321 to prevent or minimize loss
of vacuum to ambient air 322. Also, various seals known to person
of skill in the art may be utilized to seal the piston shaft
against the endplates or endcaps 317, 319 or shuttle block 321.
[0159] A shuttle block 321 or other frame, structure, or casing may
provide an outer structure for the vacuum powered mechanism 310.
Ambient air 322 refers to air at atmospheric pressure which is
located outside of the vacuum mechanism. Ambient air 322 may also
be allowed to flow inside various chambers of the vacuum powered
mechanism during use of the mechanism as described herein.
[0160] In use or in operation, the vacuum powered mechanism 310
operates by a pneumatic mechanism, method or logic that utilizes an
external or internal vacuum source to provide the force to cause
reciprocating motion of the drive piston 301 in both proximal and
distal directions. A bi-stable switch may be utilized to transition
the mechanism as it reverses or changes direction.
[0161] For example, the vacuum port 308 may be opened to the distal
drive piston chamber 307b to evacuate the distal drive piston
chamber 307b and ambient air is closed to the distal drive piston
chamber 307b, while ambient air is opened to the proximal drive
piston chamber 307a and the vacuum port is closed to the proximal
drive piston chamber 307b. The drive Piston advances toward a
distal position due to the vacuum inside the distal drive piston
chamber 307b, on the distal side of the drive piston 301 and the
ambient air pressure in the proximal cylinder chamber, on the
proximal side of the drive piston 301.
[0162] As a result of the differential pressure created on opposite
sides of the drive piston 301, the drive piston Rod or shaft 302
moves through its dwell until it contacts the bi-stable switch 303,
causing the bi-stable switch 303 to rapidly change states from a
proximal position to distal position, moving in the distal
direction. The bi-stable switch is attached to the shuttle piston
314 and rapidly causes the shuttle 314 to move from a proximal
position to distal position in the shuttle chamber. As a result,
the vacuum seal 313 on the shuttle piston 314 moves from the
proximal side of vacuum port 308 to the distal side of the vacuum
port 308, opening the vacuum port 308 to the proximal drive piston
chamber 307a to evacuate the proximal drive piston chamber 307a,
and closing the vacuum port 308 to the distal drive piston chamber
307b. Also, the distal seal 311 on the shuttle piston 314 opens the
ambient air 322 to vent the distal drive piston chamber 307b to
ambient pressure, and the proximal seal 309 on the shuttle piston
314 closes the ambient air vent to the proximal drive piston
chamber 307a.
[0163] The drive piston 301 then reverses direction and moves in
the proximal direction, due to the vacuum inside the proximal drive
piston chamber 307a, on the proximal side of the drive piston and
the ambient air pressure in the distal drive piston chamber, on the
distal side of the drive piston 301.
[0164] As a result of the differential pressure created on opposite
sides of the drive piston 301, drive piston Rod or shaft 302 moves
through its dwell until it contacts the bi-stable Switch, causing
the bi-stable switch to rapidly change states from a distal
position to a proximal position. The bi-stable switch is attached
to the Shuttle 314 and rapidly causes the Shuttle 314 to move from
its distal position to a proximal position in the shuttle chamber.
As a result, the vacuum seal 313 on the shuttle piston 314 moves
from the distal side of the Vacuum Port 308 to the proximal side of
the vacuum port 308, opening the vacuum port 308 to the distal
drive piston chamber 307b to evacuate the distal drive piston
chamber 307b, and closing the vacuum port 308 to the proximal drive
piston chamber 307a. Also, the Proximal Seal 309 on the Shuttle
piston 314 opens the ambient air 322 to vent the proximal drive
piston chamber 307a to ambient pressure, and the Distal Seal 311 on
the Shuttle piston 314 closes the ambient air vent to the distal
drive piston chamber 307b.
[0165] Consequently, the mechanism has completed one cycle and is
free to continue reciprocating as described above by alternating
suction or air pressure on opposite sides of the piston, as long as
adequate vacuum is available to the mechanism. Indeed, the above
Steps may repeat as necessary such that the vacuum powered
mechanism creates a reciprocating motion until the vacuum source is
disconnected, turned off, or if the vacuum is inadequate to
overcome the force required to move the drive piston 301 or if the
mechanism 310 is stalled or stopped.
[0166] The reciprocating motion of the mechanism may be utilized to
actuate a cutting device or to operate or actuate another device,
e.g., another medical device. In certain variations, cutting device
may be positioned by maneuvering a flexible or malleable shall of
the device e.g., manually or automatically. The shaft may be
maneuvered or positioned around sensitive tissues or structures in
the human body by changing the shape of the shaft. For example,
extending or retracting an outer sheath or cannula on the shaft or
advancing or retracting the shall relative to the outer sheath,
thereby allowing improved maneuverability of the shaft around
structures or within confined spaces may be performed, e.g.,
allowing a shaft's predetermined curvature to position the distal
end of the shaft near a target site. Such mechanisms, techniques
and devices include those described in U.S. patent application Ser.
Nos. 11/848,565, 11/848,564, and 11/848,562, each of which is
incorporated herein by reference in their entirety for all
purposes.
[0167] FIG. 4A shows a cross sectional view of another variation of
a double action vacuum powered mechanism or motor in a proximal
position, while FIG. 4B shows the double action vacuum powered
mechanism or motor in a distal position.
[0168] Referring to FIG. 4A-4B, the vacuum powered mechanism 430
includes a piston 431 having a piston shall 432. The piston 431
including at least a portion or the piston shall 432 are positioned
within a cylinder chamber 437. The piston 431 divides or separates
the cylinder chamber 437 into a proximal cylinder chamber 437a and
a distal cylinder chamber 437b. The piston 431 may reciprocate
proximally and distally within the cylinder chamber 437 when vacuum
and ambient air are alternately applied to opposite sides of the
piston 431 in cylinder chambers 437a and/or 437b. The piston 431
and piston shaft 432 may reciprocate, and the reciprocating piston
shaft 432 may conduct reciprocating motion output.
[0169] A proximal shuttle pin 433 is connected to a shuttle 444.
The shuttle pin 433 may be actuated by the piston 431 when the
piston 431 moves in the proximal direction and contacts the
proximal shuttle pin 433. Actuation of the proximal shuttle pin 433
by the piston results in movement of the shuttle 444 in the
proximal direction.
[0170] A distal shuttle pin 435 is also connected to the shuttle
444. The distal shuttle pin 435 may be actuated by the piston 431
when the piston 431 moves in the distal direction and contacts the
distal shuttle pin 435. Actuation of the distal shuttle pin 435 by
the piston results in movement of the shuttle 444 in the distal
direction. Indeed, movement of the piston in the proximal direction
results in movement of the shuttle in the proximal direction via
contact with the proximal shuttle pin 433, while movement of the
piston in the distal direction results in movement of the shuttle
in the distal direction via contact with the distal shuttle pin
435.
[0171] The shuttle 444 is positioned within a shuttle chamber. The
shuttle 444 includes a shuttle valve 443 or flange which may extend
radially therefrom, which separates or divides the shuttle chamber
into a proximal shuttle chamber 445 and a distal shuttle chamber
446.
[0172] Proximal shuttle chamber 445 may be in fluid communication
with proximal cylinder chamber 437a via proximal shuttle pin slot
434. Proximal shuttle pin slot 434 also provides an opening in
which the proximal shuttle pin 433 may translate between proximal
and distal positions. Distal shuttle chamber 446 may be in fluid
communication with distal cylinder chamber 437b via distal shuttle
pin slot 436. Distal shuttle pin slot 436 also provides an opening
in which the distal shuttle pin 435 may translate between proximal
and distal positions.
[0173] The shuttle (444) may also include a proximal ambient air
seal (439), a proximal cruciform (440), a distal ambient air seal
(441), a distal cruciform (442), and a central shall connecting the
above components.
[0174] A vacuum port (438) may be connected to an external or
internal vacuum source or supply to evacuate the proximal shuttle
chamber 445 and the distal shuttle chamber 446. The vacuum port 438
may allow for evacuation by vacuum of the proximal cylinder chamber
437a via the proximal shuttle pin slot 434 and the proximal shuttle
chamber 445. The vacuum port may allow for evacuation by vacuum of
the distal cylinder chamber 437b via the distal shuttle pin slot
436 and the distal shuttle chamber 446.
[0175] For example, Proximal Cylinder Chamber (437a) may be
evacuated by vacuum when in fluid communication with the external
vacuum source via the Vacuum Port (438), Proximal Shuttle Chamber
(445), and Proximal Shuttle Pin Slot 434. Distal Cylinder Chamber
(437b) may be evacuated by vacuum when in communication with the
external vacuum source via the Vacuum Port (438), Distal Shuttle
Chamber (446), and Distal Shuttle Pin Slot (436). Presence of
vacuum in Proximal Cylinder Chamber 437a results in differential
pressure between the proximal and distal sides of the Piston (431)
that results in working force to move the Piston (431) proximally
when ambient air is in the distal Cylinder Chamber (437b).
Alternately, ambient air (422) in proximal Cylinder Chamber 437a
applies working force to move the Piston (431) distally when the
Distal Cylinder Chamber (437b) is evacuated.
[0176] The shuttle 44 may be translated or positioned in a shuttle
chamber such that Shuttle valve 443 can seal against the shuttle
block (451) to the distal side of the vacuum port (438) to allow
the proximal shuttle chamber (445) and proximal cylinder chamber
(437a) to be evacuated by communicating with an external vacuum
supply. Alternatively, the shuttle 444 may be translated or
positioned in a shuttle chamber such that the shuttle valve 443 may
seal against the shuttle block (451) to the proximal side of the
vacuum port (438) to allow the distal shuttle chamber (446) and
distal cylinder chamber (437b) to be evacuated by communicating
with the external vacuum supply.
[0177] The proximal shuttle chamber (445) may allow for fluid
communication between the Vacuum Port (438) and the Proximal
Cylinder Chamber (437a) through the Proximal shuttle pin Slot
(434). The proximal shuttle chamber (445) may also allow for fluid
communication between the Proximal Cylinder Chamber 437a and
ambient air when the Proximal Shuttle Seal (439) is in the proximal
position, i.e., an open or unsealed position.
[0178] The Distal Shuttle Chamber (446) may allow for fluid
communication between the Vacuum Port (438) and the Distal Cylinder
Chamber (437b) through the Distal shuttle pin Slot (436). The
Distal Shuttle Chamber (446) may allow for fluid communication
between the Distal Cylinder Chamber 437b and ambient air when the
Distal Shuttle Seal 41 is in the distal position, i.e., an open or
unsealed position.
[0179] The proximal ambient air seal (439) of the shuttle 44 may
seal against shuttle block (421) to prevent ambient air leakage
into proximal shuttle chamber 445 when the proximal shuttle chamber
(445) is evacuated. Also, the proximal cruciform (440) can maintain
shuttle (444) position concentricity relative to proximal shuttle
chamber (445), e.g., when the shuttle (444) moves to a proximal
position and vents ambient air to the proximal shuttle chamber
(445).
[0180] The distal ambient air seal (441) of the shuttle 444 may
seal against shuttle block (51) to prevent ambient air leakage into
distal shuttle chamber 446 when the distal shuttle chamber (446) is
evacuated. Also, the distal cruciform (442) can maintain shuttle
(444) position concentricity relative to distal shuttle chamber
(446), e.g., when the shuttle (444) moves to a distal position and
vents ambient air to the distal shuttle chamber (446).
[0181] The vacuum powered mechanism 430 may also include a Distal
Cylinder Endcap (447), which may prevent or minimize fluid
communication between ambient air and the Distal Cylinder Chamber
(437b) in addition to providing a sealing and bearing surface with
the Piston Shaft (432). The vacuum powered mechanism 430 may also
include a Distal Cylinder Endcap Seal (448), which may prevent or
minimize ambient air leakage between the Distal Cylinder Endcap
(447) and the Piston Shaft (432), e.g., when the Distal Cylinder
Chamber (437b) is evacuated.
[0182] The vacuum powered mechanism 430 may also include a Proximal
Cylinder Endcap (449), which may prevent or minimize fluid
communication between ambient air and the Proximal Cylinder Chamber
(437a) in addition to providing a sealing and bearing surface with
the Piston Shall (432). The vacuum powered mechanism 430 may also
include a Proximal Cylinder Endcap Seal (450), which may prevent or
minimize ambient air leakage between the Proximal Cylinder Endcap
(449) and the Piston Shaft (432), e.g., when the Proximal Cylinder
Chamber (437a) is evacuated.
[0183] The piston shaft 432 may seal against the endplates or
endcaps 447, 449 or shuttle block 451 to prevent or minimize loss
of vacuum to ambient air 422. Also, various seals known to person
of skill in the art may be utilized to seal the piston shaft
against the endplates or endcaps 447, 449 or shuttle block 451.
[0184] A shuttle block 451 or other frame, structure, or casing may
provide an outer structure for the vacuum powered mechanism 430.
Ambient air 422 refers to air at atmospheric pressure which is
located outside of the vacuum powered mechanism. Ambient air 422
may also be allowed to flow inside various chambers of the vacuum
powered mechanism during use of the mechanism as described
herein.
[0185] In use or in operation, the vacuum powered mechanism 430
operates by a pneumatic mechanism, method or logic that does not
require inertial mass to move the mechanism through transition
(such as a flywheel) and that uses an external or internal vacuum
source to provide the force to cause reciprocating motion of the
piston 31 in both proximal and distal directions.
[0186] For example, the vacuum port 438 may be opened to the distal
cylinder chamber 437b to evacuate the distal cylinder chamber 437b
and ambient air is closed to the distal cylinder chamber 37b, while
ambient air is opened to the proximal cylinder chamber 437a and the
vacuum port is closed to the proximal cylinder chamber 437b. The
Piston advances toward a distal position due to the vacuum inside
the distal cylinder chamber 437b, on the distal side of the piston
431 and the ambient air pressure in the proximal cylinder chamber,
on the proximal side of the piston 431.
[0187] As a result of the differential pressure created on opposite
sides of the piston 431, the Piston 431 moves through the chamber
and contacts the distal shuttle pin 435, causing the shuttle 444 to
move from a proximal position to distal position in the shuttle
chamber. As a result, the vacuum seal 443 on the shuttle 444 moves
from the proximal side of vacuum port 438 to the distal side of the
vacuum port 38, opening the vacuum port 438 to the proximal
cylinder chamber 437a to evacuate the proximal cylinder chamber
437a, and closing the vacuum port 438 to the distal cylinder
chamber 437b. Also, the distal seal 441 on the shuttle 444 opens
the ambient air 422 to vent the distal cylinder chamber 437b to
ambient pressure, and the proximal seal 439 on the shuttle 444
closes the ambient air vent to the proximal cylinder chamber
437a.
[0188] It may be necessary to have adequate evacuated volume in the
distal cylinder chamber 437b to cause the Piston (431) to continue
translating distally after the Shuttle Valve (443) shuts off vacuum
from vacuum port 438 to the distal cylinder chamber 437b. This may
ensure that the shuttle 444 continues to translate in the distal
direction as a result of the moving piston contacting the distal
shuttle pin and thereby moving the shuttle 444, such that shuttle
valve 443 completely passes vacuum port 438, shutting off the
vacuum to the distal cylinder chamber 437b, in manner that avoids
or minimizes valve flutter or unwanted fluctuation of the valve 443
between proximal and distal positions in the shuttle chamber.
[0189] The piston 431 then reverses direction and moves in the
proximal direction, due to the vacuum inside the proximal cylinder
chamber 437a, on the proximal side of the Piston and the ambient
air pressure in the distal cylinder chamber 437b, on the distal
side of the piston 431.
[0190] As a result of the differential pressure created on opposite
sides of the piston 431, the piston 431 moves through its dwell or
the cylinder chamber and contacts the proximal shuttle pin 433,
causing the Shuttle 444 to move from its distal position to
proximal position in the shuttle chamber. As a result, the vacuum
seal 443 on the shuttle 444 moves from the distal side of the
Vacuum Port 438 to the proximal side of the vacuum port 38, opening
the vacuum port 438 to the distal cylinder chamber 37b to evacuate
the distal cylinder chamber 437b, and closing the vacuum port 38 to
the proximal cylinder chamber 437b. Also, the Proximal Seal 439 on
the Shuttle 444 opens the ambient air 422 to vent the proximal
Cylinder chamber 437a to ambient pressure, and the Distal Seal 441
on the Shuttle 444 closes the ambient air vent to the distal
cylinder chamber 437b.
[0191] Again, it may be necessary to have adequate evacuated volume
in the proximal cylinder chamber 437a to cause the Piston (431) to
continue translating proximally after the Shuttle Valve (443) shuts
off vacuum from vacuum port 438 to the proximal cylinder chamber
437a. This may ensure that the shuttle 444 continues to translate
in the proximal direction as a result of the moving piston
contacting the proximal shuttle pin and thereby moving the shuttle
444, such that shuttle valve 443 completely passes vacuum port 438,
shutting off the vacuum to the proximal cylinder chamber 437b, in
manner that avoids or minimizes valve flutter or unwanted
fluctuation of the valve 443 between proximal and distal positions
in the shuttle chamber.
[0192] Consequently, the mechanism has completed one cycle and is
free to continue reciprocating as described above by alternating
air pressure on opposite sides of the piston, as long as adequate
vacuum is available to the mechanism. Indeed, the above Steps may
repeat as necessary such that the vacuum powered mechanism creates
a reciprocating motion until the vacuum source is disconnected,
turned off, or if the vacuum is inadequate to overcome the force
required to move the Piston 431.
[0193] In certain variations of a vacuum powered mechanism, a
vacuum may be created in the "dead space" on the distal or proximal
end of the Cylinder that is adequate to cause the Piston to
continue moving distally or proximally after the external vacuum
source is shut off from the Cylinder. The "dead space" volume in
the proximal or distal end of the Cylinder serves as an
"accumulator" that encourages the Piston to continue moving
distally or proximally thereby eliminating the need for mass to
create inertia to move the valve through transitions from one state
to another.
[0194] In another variation, a method of reducing pneumatic valve
instability or flutter caused by the valve or Shuttle attempting to
move back and forth between states includes exposing one side of
the shuttle valve to the vacuum source and the opposite side of the
shuttle valve to ambient air. This may cause the shuttle valve to
move in the direction of the vacuum and will more fully open the
port connecting the ambient air to the Cylinder.
[0195] The reciprocating motion of the mechanism may be utilized to
actuate a cutting device or to operate or actuate another device,
e.g., another medical device. In certain variations, cutting device
may be positioned by maneuvering a flexible or malleable shaft of
the device e.g., manually or automatically. The shaft may be
maneuvered or positioned around sensitive tissues or structures in
the human body by changing the shape of the shaft. For example,
extending or retracting an outer sheath or cannula on the shaft or
advancing or retracting the shaft relative to the outer sheath,
thereby allowing improved maneuverability of the shaft around
structures or within confined spaces may be performed, e.g.,
allowing a shaft's predetermined curvature to position the distal
end of the shaft near a target site. Such mechanisms, techniques
and devices include those described in U.S. patent application Ser.
Nos. 11/848,565, 11/848,564, and 11/848,562, each of which is
incorporated herein by reference in their entirety for all
purposes.
[0196] Further describing operations of a variation of a mechanism
as illustrated in FIGS. 4A-4B, the shuttle 444 may start in the
proximal or distal positions. In certain variations, a small spring
(not shown) may be used to position the piston and/or the shuttle
component in a particular starting position.
[0197] FIG. 4A shows the shuttle 444 starting in the proximal
position. When external vacuum is applied to the mechanism through
the Vacuum Port (438), the Shuttle Valve (443) is on the proximal
side of the Vacuum Port (448) which results in evacuation of the
air in the Distal Cylinder Chamber (437b), the Distal Shuttle Pin
Slot (436), and the Distal Shuttle Chamber (446). Consequently, the
differential pressure on the proximal and distal sides of the
Piston (431) causes the piston to move distally.
[0198] The vacuum may apply a force greater than the frictional
forces acting on the Piston in addition to the forces required by
the mechanism to perform work.
[0199] As the Piston (431) moves distally, it contacts the Distal
Shuttle Pin (435) and moves the Shuttle (444) distally. As a
result, the Shuttle Valve (443) closes off the Vacuum Port (438) to
the distal side of the mechanism.
[0200] It may be necessary to have adequate evacuated volume on the
distal side of the chamber or in the distal cylinder chamber 437b
to cause the Piston (431) to continue translating distally after
the Shuttle Valve (443) shuts off vacuum to the distal side of the
mechanism or to the distal cylinder chamber 437b.
[0201] As the Shuttle (444) moves distally, the Distal Ambient Air
Seal (441) opens to allow ambient air from outside of the mechanism
to flow into the distal side of the mechanism and fill the
evacuated volume including the Distal Cylinder Chamber (437b), the
Distal Shuttle Pin Slot (436), and the Distal Shuttle Chamber
(446). Additionally, the Proximal Ambient Air Seal (439) closes and
the Shuttle Valve (443) opens the vacuum port 438 to the proximal
side of the mechanism and/or to the proximal cylinder chamber
437a.
[0202] The Shuttle Valve (443) moves to the distal side of the
Vacuum Port (438) which results in evacuation of the air in the
Proximal Cylinder Chamber (437a), the Proximal Shuttle Pin Slot
(434), and the Proximal Shuttle Chamber (445). Consequently, the
differential pressure on the proximal and distal sides of the
Piston (431) causes the piston to move proximally.
[0203] As the Piston (431) moves proximally, it contacts the
Proximal Shuttle Pin (433) and moves the Shuttle (444) proximally.
As a result, the Shuttle Valve (443) closes off the Vacuum Port
(438) to the proximal side of the mechanism or to the proximal
cylinder chamber 437a.
[0204] It may be necessary to have adequate evacuated volume on the
proximal side of the chamber or in the proximal cylinder chamber
437a to cause the Piston (431) to continue translating proximally
after the Shuttle Valve (443) shuts off vacuum to the proximal side
of the mechanism or to the proximal cylinder chamber 437a.
[0205] As the Shuttle (444) moves proximally, the Proximal Ambient
Air Seal (439) opens to allow ambient air from outside of the
mechanism to flow into the proximal side of the mechanism and fill
the evacuated volume including the Proximal Cylinder Chamber
(437a), the Proximal Shuttle Pin Slot (434), and the Proximal
Shuttle Chamber (445). Additionally, the Distal Ambient Air Seal
(441) closes and the Shuttle Valve (443) opens the vacuum port 8 to
the distal side of the mechanism and/or the distal cylinder chamber
437b.
[0206] The Shuttle Valve (443) is on the proximal side of the
Vacuum Port (438) which results in the mechanism being returned to
the starting position described above. Consequently, the mechanism
has completed one cycle and is free to continue reciprocating as
described above as long as adequate vacuum is available to the
mechanism.
[0207] FIGS. 5A-5B show another variation of a vacuum powered
mechanism 560 or motor including a spring return mechanism. FIG. 5A
shows the mechanism with a Piston 561 in a starting or proximal
position, and FIG. 5B shows the mechanism with a Piston 561 in a
distal position.
[0208] Referring to FIG. 5A-5B, the vacuum powered mechanism 560
includes a piston 561 having a piston shall 62. The piston 561
including at least a portion of the piston shall 562 are positioned
within a cylinder chamber 581. The piston 561 divides or separates
the cylinder chamber 581 into a proximal cylinder chamber 581a and
a distal cylinder chamber 581b. The piston 561 may reciprocate
distally within the cylinder chamber 581 when the distal side of
the piston 561 is evacuated or when distal cylinder chamber 581b is
evacuated. Ambient air may be or may always be present on the
proximal side of the piston 561 or in the proximal cylinder chamber
581a. Cylinder chamber 581a may be open to ambient air or may
always be open to ambient air. The piston shaft 565 may reciprocate
along with the piston 561, and the reciprocating piston shaft 565
may conduct reciprocating motion output. The piston shaft may serve
to transmit the motion from the piston as the mechanism output.
[0209] A shuttle 562 may be connected to the Piston (561) and the
shuttle 562 may reciprocate along with the Piston 561. The shuttle
562 may be positioned in a shuttle chamber. The shuttle includes a
proximal seal flange 563 which may be integral to the shuttle 562
and/or extend radially therefrom. The seal flange 563 provides a
seal between the Ambient Air Conduit (574) and the Distal Cylinder
Chamber (581b) when the Distal Cylinder Chamber (581b) is
evacuated. Proximal Seal Flange 563 may also contact a Proximal
Stop Pin (580) to stop the proximal movement of the Shuttle
(562).
[0210] The shuttle may also include a shuttle valve 564, which may
be integral to the shuttle and/or may extend radially therefrom.
The shuttle valve 564 may separate or divide the shuttle chamber
into a proximal shuttle chamber 588, on the proximal side of the
valve 564, and a vacuum shuttle chamber 583 on the distal side of
the valve 564. The Shuttle Valve 564 provides a seal, which may
seal, e.g., against the shuttle block 578, to the distal or
proximal side of the distal conduit 572. The shuttle valve 564 may
provide a seal to the proximal side of the distal conduit 572 to
open the distal conduit 572, and the distal cylinder chamber 581b,
to a vacuum port 575 to allow the distal cylinder chamber 581b to
be evacuated by communicating with an external vacuum supply.
[0211] The shuttle valve 564 may also provide a seal to the distal
side of the distal conduit 572 to open the distal conduit 572, and
the distal cylinder chamber 581b, to an ambient air conduit 574 to
allow the distal cylinder chamber 581b to be open to ambient
air.
[0212] The piston shall 565 may be integral to the piston 61 on the
proximal end of the piston shaft 565 and integral to the distal
piston shaft 570 (i.e., the external portion of the piston shaft
565 located at the distal end of the piston shaft 565. A Shuttle
Return Surface (566) is Integral to the Piston Shaft (565) and
serves to contact the distal end of the Shuttle (562) to motivate
it proximally when the Piston 561 and piston shaft 565 are
translating in the proximal direction.
[0213] The piston shaft 565 may also include a Distal Seal Flange
(567), which may extend radially therefrom. The distal seal flange
567 may seal ambient air in the return spring chamber 584, sealing
off the return spring chamber 584 from the shuttle vacuum chamber
583. The distal seal flange may also provide a surface for a Return
Spring (568) to act upon to motivate or translate the Piston Shaft
(565) proximally or in the proximal direction during a return
stroke.
[0214] A Return Spring (568), is positioned in the return spring
chamber 584 and stores mechanical energy by compressing during the
distal stroke of the mechanism, i.e., when the piston and piston
shaft are moved in the distal direction. The mechanical energy is
released when the Return Spring 568 motivates the Piston Shaft 565
proximally during the return stroke of the mechanism.
[0215] The mechanism 560 may include a Distal End Plate (569) which
serves as a distal stop for the Return Spring (568).
[0216] The mechanism 560 may also include various conduits. A
Proximal Conduit (571) may provide a connection or conduit for
fluid communication between the Distal Cylinder Chamber (581b) and
a Parallel Conduit (573). A Distal Conduit (572), as identified
above, may provide a connection or conduit for fluid communication
between the Proximal Shuttle Chamber (588) and the Parallel Conduit
(573). The Parallel Conduit (573) may provide a connection or
conduit for fluid communication between the Proximal Conduit (571)
and the Distal Conduit (572). The Ambient Air Conduit (574) may
provide a conduit to allow ambient air to vent proximal shuttle
chamber 588 and Distal Cylinder Chamber (581b) depending on the
positioning of shuttle valve 564 relative to the distal conduit
572.
[0217] The Vacuum Port (575) connects the mechanism to an external
vacuum source and evacuates shuttle vacuum chamber 583 and may
evacuate distal cylinder chamber 581b depending on the positioning
of shuttle valve 564 relative to the distal conduit 572.
[0218] The mechanism 560 may also include a Return Spring Vent
(576) which vents the Return Spring Chamber (584) to ambient air to
maintain ambient air pressure in the Return Spring Chamber (584) as
the chamber changes volume due to compression and extension of the
Return Spring (568). The Return spring chamber 84 contains the
return spring 68. The return spring chamber 84 may be or may always
be at ambient pressure via the return spring vent 76.
[0219] A Distal Parallel Conduit (77) may also be provided. The
distal parallel conduit 77 may be an Artifact from machining the
mechanism Block (78) and the Distal Parallel Conduit 77 may be
plugged at the distal end prior to use.
[0220] A mechanism block 578 or other frame, structure, or casing
may provide an outer structure for the vacuum powered mechanism
560. Ambient air 522 refers to air at atmospheric pressure which is
located outside of the vacuum powered mechanism. Ambient air 522
may also be allowed to flow inside various chambers of the vacuum
powered mechanism during use of the mechanism as described
herein:
[0221] A Distal Stop Pin (579) provides a distal stop for the
Shuttle (562) by preventing distal translation of the Shuttle (562)
beyond the location of the distal stop pin 579.
[0222] A Proximal Stop Pin and Ball Plunger (580) may provide a
proximal stop for the Shuttle (562) when in contact with the
Proximal Seal Flange (563). The Ball Plunger provides normal force
on the Shuttle to increase the force required to translate the
shuttle laterally thereby reducing or eliminating the likelihood of
valve "flutter" or unwanted fluctuation of the valve 564 between
proximal and distal positions in the shuttle chamber relative to
distal conduit 572.
[0223] The Distal Cylinder Chamber (581b) alternates between vacuum
and ambient pressure to motivate the Piston (561) distally when the
Distal Cylinder Chamber (581b) is in vacuum and to allow the Return
Spring (568) to motivate the Piston Shall (562) and/or piston 61
proximally when the Distal Cylinder Chamber 581b is at ambient
pressure.
[0224] The Proximal Shuttle Chamber (588) may be at ambient
pressure or may always be at ambient pressure. The Shuttle Vacuum
Chamber (583) may be evacuated or may always be evacuated when an
external vacuum source is connected to the Vacuum Port (575).
[0225] In use or in operation, the vacuum powered mechanism 560
operates by a pneumatic mechanism, method or logic whereby a vacuum
mechanism valve sequence includes shutting oil the vacuum source
from the distal cylinder chamber 81b or the mechanism to allow the
piston to return to its home position without venting the vacuum
source to ambient pressure. As a result, the vacuum pressure
remains consistent in the cutting and evacuation system portion of
the device. The pneumatic mechanism, method or logic for a piston
system that does not require inertial mass to move the mechanism
through transition (such as a flywheel) and that uses an external
or internal vacuum source to provide the force to cause
reciprocating motion in one direction and a return spring to
provide the force to cause reciprocating motion in the reverse
direction may include the following steps.
[0226] For example, a vacuum may be open to the distal Cylinder
chamber 581b while ambient air is closed to that chamber. The
Piston 561 advances in the distal direction, toward a distal
position due to the vacuum inside the distal cylinder chamber 521b
and ambient pressure in the proximal cylinder chamber 581a, on the
proximal side of the Piston 561. Distal advancement of the Piston
561 compresses the Compression Spring 568, where the vacuum force
should or may be great enough to overcome friction in order to
compress the Compression Spring 568.
[0227] When the piston 561 moves, the piston 561 contacts Shuttle
562 and advances the Shuttle 562 such that the shuttle valve 564
cuts off the vacuum to the distal Cylinder chamber 581b and the
Compression Spring 568 continues to compress as the Piston 561
advances in the distal direction. Piston 561 may continue to
advance distally (e.g., even after the vacuum is cut off to distal
cylinder chamber 581b) due to evacuated volume on the distal side
of the Cylinder in the distal cylinder chamber 581b, which should
or may be great enough to overcome friction and to continue
compressing the Compression Spring 568 and advancing the shuttle
562 to allow ambient air to flow into the distal cylinder chamber
581b by opening distal conduit 572 and distal cylinder chamber 581b
to ambient air conduit 574.
[0228] The Piston 561 may retract in the proximal direction to a
proximal position due to the force of the Compression Spring 568
and a loss of vacuum in the distal cylinder chamber 581b resulting
from ambient air flowing into the distal cylinder chamber 581b. The
Piston Shaft 562 contacts the Shuttle and moves the shuttle in a
proximal direction, thus cutting off ambient air conduit 574 and
ambient air flow to the distal Cylinder chamber 581b. The Piston
Shaft 562 continues moving the Shuttle 562 proximally, eventually
opening the distal conduit 572 and distal cylinder chamber 581b to
vacuum port 575 such that the vacuum connection is open to the
distal cylinder chamber 581b.
[0229] The mechanism is free to continue reciprocating as described
above by creating a pressure differential on opposite sides of the
piston as long as adequate vacuum is available to the mechanism.
The above steps may repeat as necessary such that the vacuum
powered motor creates a reciprocating motion unless or until the
vacuum source is disconnected, turned off, or if the vacuum is
inadequate to overcome the force required to compress the
Compression Spring and overcome the internal friction or if the
mechanism is stalled or halted.
[0230] In certain variations, Pneumatic valve instability or
flutter caused by the shuttle or shuttle valve attempting to move
back and forth between states, or between proximal and distal
positions relative to distal conduit 572, may be reduced or
eliminated by exposing one side of the shuttle valve 564 to the
vacuum source and the opposite side of the Shuttle valve 564 to
ambient air. This will cause the Shuttle or shuttle valve to move
in the direction of the vacuum and will more fully open the distal
conduit 572 to the ambient air conduit 574, thereby connecting the
ambient air to the distal Cylinder chamber 581b.
[0231] In certain variations, a small normal force may be imparted
on the Shuttle 562 to hold it in place to overcome unintended
movement caused by friction against the Piston Shaft 565 or valve
flutter caused by valve instability. This small normal force may be
imparted in the form of a ball plunger.
[0232] In certain variations of a vacuum powered mechanism, an
adequate volume is evacuated on the distal end of the Cylinder or
from the distal cylinder chamber to cause the Piston to continue
moving distally after the external vacuum source is shut off from
the distal Cylinder chamber. The evacuated volume in the distal
Cylinder chamber serves to encourage the Piston to continue moving
distally after the external vacuum source is shut off from the
volume of the distal cylinder chamber, thereby eliminating the need
for inertial mass to move the valve through transitions from one
state to another.
[0233] The reciprocating motion of the mechanism may be utilized to
actuate a cutting device or to operate or actuate another device,
e.g., another medical device. In certain variations, cutting device
may be positioned by maneuvering a flexible or malleable shaft of
the device e.g., manually or automatically. The shall may be
maneuvered or positioned around sensitive tissues or structures in
the human body by changing the shape of the shaft. For example,
extending or retracting an outer sheath or cannula on the shaft or
advancing or retracting the shaft relative to the outer sheath,
thereby allowing improved maneuverability of the shaft around
structures or within confined spaces may be performed, e.g.,
allowing a shaft's predetermined curvature to position the distal
end of the shaft near a target site. Such mechanisms, techniques
and devices include those described in U.S. patent application Ser.
Nos. 11/848,565, 11/848,564, and 11/848,562, each of which is
incorporated herein by reference in their entirety for all
purposes.
[0234] Further describing operations of a variation of a mechanism
as illustrated in FIGS. 5A-5B, FIG. 5A shows a starting position
for the mechanism with the Piston in a proximal position due to
extension of the Return Spring (568).
[0235] When external vacuum is applied to the mechanism through the
Vacuum Port (575), the Shuttle Valve (564) is on the proximal side
of the Vacuum Port (75) and on the proximal side of the Distal
Conduit (572). As a result, the vacuum is able to fluidly
communicate with the Distal Cylinder Chamber (581b) which results
in evacuation of the air in the Distal Cylinder Chamber (581b).
Consequently, the differential pressure on the proximal and distal
sides of the Piston (561) causes the piston to move distally.
[0236] As the Piston (561) moves distally, it compresses the Return
Spring (568) thereby storing mechanical energy. The Proximal
Shuttle Seal (563) prevents leakage of ambient air into the Distal
Cylinder Chamber (581b). The Shuttle (562) "dwells" in position
until the Piston (561) contacts the Shuttle (562) and motivates it
in the distal direction. The Shuttle Valve (564) then closes off
the Vacuum Port (575) to the Distal Conduit (572) thereby shutting
off vacuum to the Distal Cylinder Chamber (581b).
[0237] It may be necessary to have adequate evacuated volume on the
distal side of the chamber in the distal cylinder chamber 581b to
cause the Primary Piston (561) to continue translating distally
after the Shuttle Valve (564) shuts off vacuum to the distal
conduit 572 and the distal cylinder chamber 581b.
[0238] As the Distal Cylinder Chamber (581) refills with ambient
air, from ambient air conduit 574 via distal conduit 572 (which is
now open to ambient air conduit 514 as shown in FIG. 5b), the
Return Spring (568) motivates the Piston Shaft (565) proximally.
The Shuttle "dwells" in position until the Shuttle Return Surface
(566) on the Piston Shalt (565) contacts the Shuttle (562) and
motivates the Shuttle (562) in the proximal direction.
[0239] The Shuttle Valve (364) moves from the distal side to the
proximal side of the Distal Conduit (572) thereby opening the
distal conduit 572 to the Vacuum Port (575) to evacuate the Distal
Cylinder Chamber 581b).
[0240] The Shuttle (562) and the Piston 561 return to their
proximal (starting) position and the mechanism has completed one
cycle and is free to continue reciprocating as described above as
long as adequate vacuum is available to the mechanism.
[0241] In any of the variations of vacuum powered mechanisms
described herein, O-rings or other sealing components may be used
to create a seal between surfaces but are not necessary if leakage
around the seals is tolerable. Also, leakage around the seals may
be reduced by using a lubricant of sufficient viscosity to fill the
gap between the seal and the bore in which it operates.
[0242] The Shuttle may be configured in several positions including
concentric with the Center Shaft, parallel to the Center Shaft, as
a rotary valve, and so forth.
[0243] The vacuum powered mechanisms described herein may be
utilized with or incorporated into a variety of medical devices.
For example, the vacuum powered mechanisms may be utilized to
reciprocate a cutter on a distal end of a malleable shaft which may
be manipulated or adjusted manually or automatically or a flexible
shaft having a predetermined curvature which is manipulated through
advancement or retraction through a cannula or other sheath as
illustrated and described in U.S. patent application Ser. Nos.
11/848,565, 11/848,564, and 11/848,562, each of which is
incorporated herein by reference in their entirety for all
purposes. U.S. Patent Application No. 61/360,429 is also
incorporated herein by reference in its entirety for all
purposes.
[0244] In certain variations of a device having a curved flexible
shaft, a rigid or semi-rigid straight sheath may be assembled or
connected to the device to cause the curved, flexible portion of
the shaft to straighten as the sheath is advanced over the curved
section or to cause the curved, flexible portion of the shaft to
return to its curved shape as the sheath is retracted.
[0245] In other variations, a rigid or semi-rigid curved sheath may
be assembled or connected to a device or end effector having a
shall with a curved, flexible portion to direct the shall as it is
advanced through the curved sheath.
[0246] In other variations, a rigid or semi-rigid curved sheath may
be assembled or connected to a device or end effector having a
shaft with a straight, flexible portion to direct the shall as it
is advanced through the curved sheath. The rigid or semi-rigid
curved or straight sheathes may be assembled, connected, attached
to or otherwise utilized with the cutting device. The various
sheaths may be detachable from the devices or end effectors or
affixed or attached to the devices and or end effectors.
[0247] In certain variations, the vacuum powered mechanisms
described herein may also be utilized to reciprocate or actuate a
reciprocating cutter of a device or end effector or to operate a
device having a semi-rigid or rigid, curved end effector or a rigid
or stiff shaft. A cutter, end effector and/or device may be
operated by vacuum powered mechanisms or other motorized mechanisms
or by hand.
[0248] FIG. 6 shows one variation of a rigid, curved end effector
4.0 or distal end of a device. The end effector 4.0 may include a
scraping edge 4.1, a window 4.6, a reciprocating cutter 4.2, and/or
a blunt distal tip 4.5. The end effector 4.0 may also include a
rigid shaft 4.7. The rigid shaft 4.7 may have a shaft curvature
section 4.3 and/or a shaft straight section 4.4. In certain
variations, a fluid line 4.8, e.g., a saline line, may be attached
to the end effector 4.0 or extend along or within the end effector
4.0. In certain variations, the end effector, distal end of a
device, and/or shaft may be rigid, stiff, substantially rigid, or
semi rigid.
[0249] The end effector 4.0 may be a component of a device, e.g., a
cutting device or medical device. The end effector 4.0 may be
positioned at a distal end of a cutting device or designed for use
or attachment to a cutting device, medical device, or other device.
The end effector 4.0 may be useful for various procedures requiring
cutting and/or scraping of a variety of tissues including soft and
hard tissues.
[0250] The Scraping Edge 4.1 is typically made from a rigid
material, e.g., Stainless Steel, which may withstand cutting forces
without substantially bending or deflecting the scraping edge 4.1.
Other materials may be used as warranted by the desired clinical
application. In certain variations, a semi-rigid material may be
used. The Scraping Edge 4.1 may be used to cut or scrape various
soft and hard tissues, such as intradiscal nucleus tissue,
Vertebral End Plates, cartilage, ligament, bone, and other soft and
hard tissues. The Scraping Edge 4.1 may be used to cut tissue free
and/or to mobilize the tissue for evacuation through the Window 4.6
and through a lumen of the rigid shall 4.7. The tissue may be
evacuated to a Filter or collection receptacle.
[0251] The Scraping edge 4.1 may be affixed or attached to the
rigid shaft 4.7 at any angle relative to the longitudinal axis of
the Rigid Shaft 4.7. For example, the scraping edge 4.1 may be
affixed or attached to the Rigid Shaft 4.7 at a an angle ranging
from or between 0 to 180 degrees or 0 to 90 degrees relative to an
axis of the Rigid Shaft 4.7. As shown in FIG. 6, in certain
variations, the Scraping Edge 4.1 may be affixed or otherwise
attached to the Rigid Shaft 4.7 in a position that is perpendicular
or substantially perpendicular to the axis of the rigid shaft
4.7.
[0252] Where the Scraping Edge 4.1 is rigidly affixed to the Rigid
Shaft 4.7 as shown in FIG. 6, the cutting and scraping actions of
the scraping edge 4.1 may be accomplished by the operator manually
moving the Scraping Edge 4.1 through manual movement of the rigid
shaft 4.7 or the end effector 4.0 or a component thereof.
Optionally, the cutting and scraping actions of the scraping edge
4.1 may be accomplished automatically or by motorized movement or
operation of the rigid shaft 4.7 or the end effector 4.0 or a
component thereof.
[0253] In certain variations, the Scraping Edge 4.1 may be affixed
or attached to the Reciprocating Cutter 4.2, e.g., external to the
Rigid Shaft 4.7, such that the scraping edge 4.1 can reciprocate in
concert with the cutter (not shown). The scraping edge 4.1 may be
affixed or attached to the reciprocating cutter 4.2 at any angle
relative to the longitudinal axis of the Reciprocating Cutter 4.2.
For example, the scraping edge 4.1 may be affixed or attached to
the Reciprocating Cutter 4.2 at a an angle ranging from or between
0 to 180 degrees or 0 to 90 degrees relative to an axis of the
Reciprocating Cutter 4.2. In certain variations, the Scraping Edge
4.1 may be affixed or otherwise attached to the Reciprocating
Cutter 4.2 in a position that is perpendicular or substantially
perpendicular to the axis of the Reciprocating Cutter 4.2.
[0254] The Scraping Edge 4.1 may be positioned at a location distal
to the Window 4.6 and/or the scraping edge 4.1 may be predominately
aligned with the Window 4.6 and/or positioned on the same side of
the Rigid Shaft 4.7 as the Window 4.6. The Scraping Edge 4.1 may be
positioned distal or proximal to the Window 4.6. Optionally, the
scraping edge 4.1 may have exposed scraping surfaces at any
location around the periphery of the Rigid Shaft 4.7 or
reciprocating cutter 4.2.
[0255] In certain variations, the end effector 4.0 may be built
without a Scraping Edge 4.1. Indeed, an end effector 4.0 may or may
not include a scraping edge 4.1 depending on the desired clinical
application. In certain variations, one or more scraping edges may
be positioned on an end effector, e.g., a plurality of scraping
edges may be positioned on an end effector.
[0256] Still referring to FIG. 6, the Reciprocating Cutter 4.2 may
be positioned on the end effector 4.0 such that the reciprocating
cutter 4.2 may advance and/or retract axially past the Window 4.6
to excise and evacuate tissue or mobilized tissue. The
Reciprocating Cutter 4.2 may use a "scissor" action against the
window 4.5 or against a section of the rigid shaft 4.7 to excise
tissue.
[0257] The Window 4.6 is an opening in the Rigid Shaft 4.7 that
permits the passage of tissue into the window 4.6 and into the path
of the Reciprocating Cutter 4.2 such that the tissue can be cut
and/or evacuated. The Window 4.6 or at least a portion of the
perimeter or an edge of the window 4.6 may serve as a cutting edge
to "plane" tissue and excise the tissue. Additionally, an edge of
the Window 4.6 may provide a surface with which the Reciprocating
Cutter 4.2 may scissor tissue as the reciprocating cutter 4.2
passes by the Window 4.6.
[0258] The Reciprocating Cutter 4.2 may be powered or actuated by
any of the vacuum powered mechanisms described herein.
Alternatively, the reciprocating cutter 4.2 or end effector may be
actuated through a mechanism that is powered by hand or by other
motorized mechanisms. In certain variations, a rotating cutter may
be utilized and powered by any of the vacuum powered mechanisms
described herein, by hand or by other motorized mechanisms.
[0259] The Rigid Shaft 4.7 may serve as the primary structure
and/or outer envelope of the shaft of a device or cutting device to
which the end effector is attached. The Rigid Shaft 4.7 may be
curved or straight or the rigid shaft 4.7 may include curved and/or
straight sections or portions. In certain variations, the rigid
shaft 4.7 may be malleable to allow an operator or user to adjust
or revise the curvature of the shaft 4.7 depending on the
application or use. For example, the rigid shaft 4.7 may be
bendable or the rigid shaft 4.7 may be annealed or softened in
order to alter the shape or curve of the rigid shaft 4.7 by hand or
machine. The rigid shaft may be annealed over the bendable portion
of its length and hard near the distal extremity to reduce the
likelihood of bending or damaging the shall near the cutting
window.
[0260] As shown in FIG. 6, a Shall Curvature section 4.3 may be
provided in the rigid shaft 4.7. The rigid shaft may include one or
more shaft curvature sections. The shall curvature section 4.3
allows the operator to position the end effector 4.0 or the distal
end of the end effector 4.0 or the distal end of the cutting device
or other device in an area of anatomy outside of the line-of-sight
of the user. For example, the shaft curvature section 4.3 may allow
the end effector 4.0 to be positioned within an intradiscal space.
The radius of curvature of the rigid shaft 4.7 or the shaft
curvature section 4.3 may be determined during manufacturing or it
may be operator-adjustable.
[0261] The rigid shaft 4.7 may also include a Shaft Straight
Section 4.4 which may be located proximal to the Shaft Curvature
section 4.3. The rigid shaft may include one or more shaft straight
sections.
[0262] A Blunt Distal Tip 4.5 may be provided on the end effector
4.0. The blunt distal tip 4.5 may significantly reduce, minimize or
eliminate the likelihood of the end effector 4.0 or distal end of a
device accidentally being advanced through or into tissue which is
not the intended target. For example, the blunt distal tip 4.5 may
reduce the likelihood or minimize the risk of the end effector 4.0
or distal end of the device being advanced through an annulus when
the end effector 4.0 of a device is being used to cut intra-discal
nucleus or for scraping and/or evacuating vertebral endplate
material. The blunt distal tip 4.5 may cover all or a portion of
the distal surface of the Scraping Edge 4.1. In variations where
the entire distal surface or substantially the entire surface of
the Scraping Edge 4.1 is covered with the Blunt Distal Tip 4.5, the
Scraping Edge 4.1 may cut and/or scrape only when moved in the
proximal direction or a lateral direction and not when moved in the
distal direction. In other variations where the entire distal
surface or substantially all of the distal surface of the Scraping
Edge 4.1 is covered with the Blunt Distal Tip 4.5, the Scraping
Edge 4.1 may cut and/or scrape in the distal direction or it may
cut and/or scrape in the distal direction in a limited manner.
[0263] In certain variations, a fluid line 4.8 may be affixed or
attached to the external or outside surface or the Rigid Shaft 4.7
as shown in FIG. 6. Optionally, the fluid line 4.8 may be contained
inside the Rigid Shaft 4.7 by a separate lumen within the rigid
shall 4.7 or by allowing fluid to flow through the main shaft
lumen. The fluid Line 4.8 allows fluids, e.g., saline, water, air,
etc., to flow from a source of fluid external or internal to a
device to the distal end of the end effector or the distal end of a
device or cutting device.
[0264] A scraping edge 4.1 may be provided or located on an end
effector 4.0 having a rigid shaft 4.7, where the rigid shall 4.7
and scraping edge 4.1 allow side or axial forces to be applied to
the rigid shaft, scraping edge, end effector and/or to a device
attached to the end effector to effect scraping or cutting of
tissue in a vertebral disc or tissue in another area of the
anatomy, while minimizing or preventing deflection or bending of
the end effector, shaft or scraping edge. A rigid end effector
having a rigid shall and/or scraping edge may permit or provide
effective scraping and/or cutting of a target tissue. Optionally, a
scraping edge may be positioned on the distal end of a flexible,
semi-rigid or less rigid shaft or end effector and side forces may
be applied to the scraping edge and shaft to effect scraping. In
any of the above variations, axial advancement and retraction of
the scraping device and/or end effector may result in the scraping
or breaking up of tissue, such as vertebral disc tissue.
Optionally, one or more scraping edges may be positioned adjacent
to the cutting window to position the scraping edge nearly
perpendicular to the direction of motion when a curved shaft is
used.
[0265] In certain variations, an apparatus for scraping tissue in a
subject is provided. The apparatus includes an end effector. The
end effector includes a scraping edge positioned on a distal end of
the end effector and one or more scraping wings, edges or
protrusions positioned at an angle relative to the scraping edge
such that the end effector may be actuated in a back and forth
motion approximately perpendicular to the scraping edge to scrape
or gather tissue, and/or actuated in a back and forth motion
approximately perpendicular to the scraping wings to scrape or
gather tissue. The scraping wings may serve to collect tissue at
the cutting window opening to improve resection.
[0266] In certain variations, the end effector may include a
scraping edge positioned on a distal end of the end effector and
one or more scraping wings positioned at an angle relative to the
scraping edge such that the scraping edge and scraping wings can
provide a scraping motion in different directions.
[0267] FIG. 7 shows another variation of an end effector 704 or
distal end of a cutting or scraping device. The end effector 704
may include a scraping edge 701, a window 706, a reciprocating
cutter 702, and/or a blunt distal tip 705. The reciprocating cutter
may be positioned within the end effector. The end effector 704 may
include a rigid or flexible shalt 707. The end effector may include
one or more wings 708 positioned at an angle to the scraping edge
701, e.g., such as but not necessarily next to the window 706. The
wings 708 may be used to scrape, gather and/or cut tissue.
[0268] Wings 708 may be positioned on the end effector at an angle
relative to the scraping edge 701. For example, the wings 708 may
be positioned at an angle ranging from 0 to 90 degrees, e.g. at
about 90 degrees, relative to the scraping edge 701. The wings 708
are positioned at an angle relative to the scraping edge 701 such
that in use, the scraping edge 701 and wings 708 may work or scrape
tissue in different directions. The end effector 704 may be used to
cut or scrape a variety of tissues in various regions of the body.
For example, the end effector may be utilized to cut, scrape and/or
gather tissue in a spine or spinal disc, e.g., to perform a
discectomy.
[0269] In the variations described herein, the dimensions of the
end effectors, shafts, devices, and/or the various components of
the end effectors, shafts or devices are merely exemplary in nature
and are not intended to be limiting. It is also contemplated that
in certain variations, one or more of the various components of the
end effectors or the devices, or one or more of the end effectors
or the devices may be provided or utilized.
[0270] In certain variations, the various sheaths described herein
for guiding a shaft or end effector may be used with a device or
end effector having a curved or straight flexible or rigid
shaft.
[0271] The cutting devices or scrapers described herein may be
utilized to perform a discectomy or other spinal procedures.
Additionally, the devices described herein may be utilized or
provide methods for resecting, excising and/or removing tissue or
soft tissue from various regions in a patient's or subject's body.
For example, the devices described herein may be utilized to excise
and/or remove or evacuate various tissues or cells including, but
not limited to: nasal tissue, for example, nasal polyps; eye
tissue; tissue in various gynecological procedures; tumors, e.g.,
cancerous tumors in the lungs, liver, and in other vital organs;
and tissues or cells from other areas in a patient or subject.
[0272] An end effector with a reciprocating or "fixed" Scraper edge
4.1, a Reciprocating Cutter 4.2, and/or a Rigid Shaft 4.7 (as shown
in FIG. 6) or an end effector of FIG. 7 may be useful for excising
and/or evacuating various tissues. Such tissues include tissues
within the full spectrum of consistency ranging from soft tissues,
such as intradiscal nucleus pulposis, to tough tissues, such as End
Plate cartilage and ligament, to hard tissues, such as hone. For
example, the end effector may be used to prepare the intradiscal
space for vertebral fusion procedures where, e.g., it may be
desirable to remove the intradiscal nucleus pulposis and End Plate
cartilage and scrape the underlying bone to cause bleeding of the
bone to promote healing and fusion between the vertebral bodies and
implant.
[0273] In certain variations, an end effector having a Rigid Shalt,
a Reciprocating Cutter 4.2, and/or with or without a Scraping Edge,
may be useful for excising and/or evacuating tissues in procedures
such as a foramenotomy, where it is desirable to decompress an
emanating nerve that passes through a stenosed foramen. The end
effector having a curved, rigid shaft with or without a Scraping
Edge (4.1) may be capable of reaching into the foramen and exposing
the Window (4.6) to the inside surface of the foramen such that the
reciprocating cutter 4.2 and/or the scraping edge 4.1 may excise
tissue. The end effector may be utilized in both "open" and
percutaneous surgical procedures.
[0274] Optionally, an end effector or device having a flexible
shaft may be used in the tissue excising, scraping or evacuating
procedures described above.
[0275] In certain variations, a device may include or a method may
utilize a cutter positioned at the distal end of a flexible shaft
that has a preformed or predetermined curvature. The shaft may be
adapted for insertion into a cannula or sheath where the distal end
of the shaft may advance from the cannula (by advancing or
retracting the cannula and/or the shaft relative to each other)
toward a target site and the shaft may be configured to allow its
predetermined curvature to position the distal end of the shall
near the target site, for example, by reverting or beginning to
revert to its predetermined curvature upon exiting the cannula or
sheath.
[0276] The devices described herein include a mechanism powered by
a vacuum source. The devices may be used for applications where a
source of vacuum is present. For example, a source of vacuum is
frequently available when medical procedures are performed. Many
medical devices utilize a reciprocating mechanism to perform their
function. The devices described herein may be useful in procedures
where evacuation or aspiration is necessary and the device may
include evacuation or aspiration features in combination with a
vacuum powered reciprocating mechanism.
[0277] In certain variations, a device using an external or
internal vacuum source to power a reciprocating mechanism that is
connected to a cutter thereby causing the cutter to reciprocate may
include a "Y" connection within a handle that connects the vacuum
source to both the cutter evacuation tube and the vacuum powered
mechanism. As a result, the vacuum performs several functions
within the device, such as: powers the mechanism which causes the
cutter to reciprocate, draws tissue into a cutting window such that
it may be excised, and/or evacuates the excised tissue to a
location external to the device, while maintaining a consistent
vacuum pressure even when the vacuum source is shut off to the
mechanism during reciprocation.
[0278] In certain variations, a cutting device implements a
pneumatic logic or a method utilizes a pneumatic logic to operate a
cutting or other reciprocating device whereby a vacuum mechanism
valve sequence shuts off the vacuum source from the mechanism to
allow a piston to return to its home position without venting the
vacuum source to ambient pressure. As a result, the vacuum pressure
remains consistent in the cutting and evacuation system portion of
the device.
[0279] In certain variations, a method includes maneuvering a
flexible shall around sensitive tissues or structures in the human
body by changing the shape of the shaft by extending or retracting
an outer sheath on the shaft thereby allowing improved
maneuverability of the shaft around structures or within confined
spaces. Such a shall and sheath may be incorporated in any of the
devices or vacuum powered devices describe herein.
[0280] In certain variations, a semi-rigid or rigid outer sheath
positioned over the flexible curved shaft that is used to change
the radius of curvature of the curved shaft may be provided. The
radius of curvature of the shaft increases when the straight and
rigid sheath is extended over the curved portion of the shaft,
whereas the radius of curvature of the shaft returns to its
precurved shape when the sheath is retracted from the curved
portion of the shaft.
[0281] In certain variations, an electrically resistive, or bipolar
or monopolar electrocautery system is included on the distal tip of
the shaft that allows the physician to cauterize tissue to control
bleeding at the operative site. The electrocautery system may be
powered by wires that run the length of the shaft through an
internal lumen within the shall.
[0282] In certain variations, a cutting device utilizing any of the
variations of vacuum powered mechanisms described herein results in
automatic actuation of a cutter positioned on a flexible or rigid
shaft, thereby providing a vacuum powered cutter. The vacuum
mechanism for actuating the cutter may enable controls to be
utilized for other functions or functions other than operating the
mechanism, thereby reducing the number of levers or control buttons
on the device. For, example, other controls positioned on the
device may be utilized for straightening or curving the shaft or
for operating or controlling bipolar systems for cauterizing.
[0283] In one variation, the device may include a handle having a
trigger. Actuation of the trigger may cause a cannula or sheath
positioned over a flexible shaft extending from the handle to
either extend or retract, depending on whether the trigger is
pressed or released. The extension or retraction of the cannula may
cause the flexible shaft to straighten or curve. The device may
include a roller ball, knob or other control mechanism for
adjusting or for turning on/off vacuum flow or ambient flow to
thereby regulate cutting speed. For example, such a knob or roller
ball may be positioned on the cutting device such that the knob or
roller ball may be manipulated by a thumb or other finger on the
hand holding the handle of the device or on a free hand of the
user. Thus, the cutting device can by used with one hand, freeing
up the other hand of the user or physician for other uses. A single
vacuum line may attach to the device, which both evacuates excised
tissue and powers the mechanism. For example, a "Y" connection
within the handle of the device may connect the vacuum source to
both the cutter evacuation tube and the vacuum powered mechanism,
where the device maintains a consistent vacuum pressure or force at
the cutting window for evacuating excised tissue during operation
of the mechanism.
[0284] The mechanism according to the variations described herein
may actuate a cutter automatically by using a mechanism powered by
an external vacuum source. The external vacuum source may be
connected to the device to provide suction to facilitate tissue
cutting and evacuation, therefore, the use of the external vacuum
source to power the cutter is completed without requiring an
additional power source such as electricity, compressed air, or
mechanical input by the operator.
[0285] Because vacuum power is used to actuate the cutter, operator
fatigue may be reduced as compared to a system requiring the
operator to manually actuate the reciprocating mechanism such as
via button or trigger mechanism. Also, the use of vacuum to power
the cutter actuation may significantly increase the rate at which
the cutter actuates, thereby reducing the time required to complete
tissue resection.
[0286] The use of vacuum power to actuate the cutter may allow the
control for the rate of actuation to be moved from a "primary"
position such as a trigger or button to a "secondary" position on
the device handle. As a result, the primary control may be utilized
to control the rate at which the cutter mechanism actuates or as a
control for the radius of curvature of the shaft, or as a control
for an electrocautery system.
[0287] A knob, trigger, roller clamp, or other control interfaces
may be used to control the rate at which the vacuum mechanism
reciprocates. These options allow the device to be designed in a
variety of configurations to suit various surgical specialties or
personal preferences.
[0288] The various pneumatic logic sequences utilized by the
systems described herein may optionally maintain high vacuum
throughout the engine cycle by never venting the vacuum source to
the atmosphere. As a result, the vacuum pressure that facilitates
cutting and evacuation may not decrease while the mechanism
reciprocates.
[0289] A single tube from the vacuum source to the device to serve
the functions of tissue cutting, evacuation and to power the
mechanism which actuates the reciprocating cutter may be utilized.
The single tube from the vacuum source simplifies connections
required for device operation and reduces the number of tubes
attached to the device thereby reducing the "clutter" and
unwieldiness caused by multiple tubes and wire connections to the
device.
[0290] In certain variations, a second source of vacuum may be
provided such that separate vacuum sources power the mechanism and
provide suction to the distal end of the cutting device or end
effector for excising and/or evacuating tissue. In certain
variations, one or more vacuum sources and/or one or more tubes or
conduits connecting a vacuum source to a device to supply suction
to the device and/or to power the device may be utilized or
provided.
[0291] A cannula may be used on the flexible shall to change the
radius of curvature on the shaft in a range from nearly straight to
curved in an arc or 180 degrees. This allows the operator to
optimize the curvature of the shaft based on the patient anatomy.
The operator can increase or decrease the force between the shall
and the target tissue being excised by extending or retracting the
cannula to increase or decrease the natural radius of curvature of
the shaft.
[0292] Optionally, an electrically resistive, or monopolor or
bipolar cautery may be used on the distal tip of the devices
described herein to allow the operator to cauterize tissue to
control bleeding at the site where tissue has been excised. This
feature obviates the need to remove the device from the operative
site to replace it with an electrocautery device. This improves
speed and ease-of-use for the operator while reducing blood loss
for the patient.
[0293] The devices described herein may be manufactured using low
cost components and assembly techniques; as a result, the cost of
the device is much lower than a similar device which utilizes an
electric motor.
[0294] The devices described herein may have a relatively low mass
and may be easily sterilized using commonly used sterilization
techniques such as, e.g., electron beam radiation, gamma radiation,
or Ethylene Oxide gas.
[0295] Other variations of vacuum powered devices and methods are
provided below. For example, a medical device may utilize a
mechanism powered bran external source of vacuum to perform one or
more function(s) through reciprocating motion output by the
mechanism. The device may excise and evacuate tissue. The device
may have a single attachment to an external vacuum source wherein
said vacuum provides power to the mechanism and assists in excising
tissue. The device may have a single attachment to an external
vacuum source wherein said vacuum provides power to the mechanism
and assists in evacuating tissue. The device may utilize a
mechanism that does not utilize inertia of mass to transition past
valves to change state. The device may not vent the external vacuum
source to ambient air at any time during its cycle thereby causing
a drop in vacuum within the device. The device may include a
flexible shaft that has a preformed curvature on the distal portion
and a straight rigid or semi-rigid cannula around the outer
diameter of the shaft; the radius of curvature of the shaft may be
changed by sliding the cannula over the distal curvature whereby
the radius of curvature is increased when the cannula is extended
over the distal curvature and the distal curvature returns to its'
preformed curvature when the cannula is retracted from the distal
curvature. The device may include a monopolar electrode or bipolar
electrodes on or near the distal extremity. The device may have a
single connection to an external vacuum source that powers a vacuum
powered mechanism and evacuates excised tissue. The single
connection to an external vacuum source may also use vacuum to draw
tissue into a cutting window to present tissue for the purpose of
excising said tissue.
[0296] A medical device may include a mechanism powered by an
external vacuum source wherein said mechanism is comprised or a
piston that is set into motion by creating differential pressure on
either side of the piston wherein one side of the piston has
ambient air and the air on the other side of the piston is at least
partially evacuated. The mechanism may include a valve component
that opens the volume next to the Piston alternately to ambient air
or vacuum. The valve component may be actuated as a result of
translation of the Piston wherein the Piston acts upon the valve to
cause it to open or close the fluid connections to ambient air or
to the external vacuum source.
[0297] A method for causing a reciprocating mechanism powered by
vacuum to transition past valves to change states wherein an
adequate volume of air has been evacuated prior to closing the
valve to the external vacuum source such that the mechanism
continues to move into the evacuated volume such that the valve
fully transitions to open the source of vacuum to a different
volume may also be provided.
[0298] The method may include the following logic sequence: Vacuum
open to the distal side of the Cylinder, ambient is closed to
distal; ambient open to proximal side of Cylinder, vacuum is closed
to proximal; Piston advances toward distal position due to the
vacuum inside the distal side of the cylinder and ambient pressure
on the proximal side of the Piston; Piston contacts Shuttle and
advances it toward the distal position; Vacuum Seal on Shuttle
moves from proximal side of Vacuum Port to the distal side of the
Vacuum Port while the Distal Seal on the Shuttle opens the ambient
air to vent the distal side of the Cylinder to ambient pressure and
the Proximal Seal on the Shuttle closes the ambient air vent to the
proximal side of the Cylinder; Piston reverses direction and moves
in the proximal direction due to the vacuum inside the Cylinder
proximal to the Piston and ambient air on the distal side of the
Piston; Piston contacts Shuttle and advances toward the proximal
position; Vacuum Seal on Shuttle moves from distal side of Vacuum
Port to the proximal side of the Vacuum Port while the Proximal
Seal on the Shuttle opens the ambient air to vent the proximal end
of the Cylinder to ambient pressure and the Distal Seal on the
Shuttle closes the ambient air vent to the Distal side of the
Cylinder. The above steps may repeat unless the vacuum source is
disconnected, turned off, or if the vacuum is inadequate to
overcome the force required to move the Piston.
[0299] Optionally, the method may include the following logic
sequence: Vacuum open to the distal side of the Cylinder, ambient
is closed to distal; ambient open to proximal side of Cylinder;
Piston advances toward distal position due to the vacuum inside the
distal side of the cylinder and ambient pressure on the proximal
side of the Piston; Piston contacts Shuttle and advances it toward
the distal position; Vacuum Seal on Shuttle shuts off vacuum to the
distal side of the Piston and continues to move distally thereby
opening the ambient air supply to the distal side of the Piston;
Return Spring motivates the Piston in the proximal direction due to
the equalization of air pressure on both sides of the Piston;
Piston Shaft contacts Shuttle and motivates it in the proximal
direction; Shuttle Seal on the Shuttle shuts off ambient air supply
to the distal side of the Piston and opens the vacuum to the distal
side of the Piston. The above steps may repeat unless the vacuum
source is disconnected, turned off, or if the vacuum is inadequate
to overcome the force required to move the Piston.
[0300] In another variation, a medical device includes a
reciprocating cutting blade such as is used to excise and evacuate
tissue that uses a reciprocating mechanism powered by an external
vacuum source that may be used for medical procedures where a
source of vacuum is present.
[0301] The above arrangements, materials, and dimensions for the
vacuum powered mechanisms described herein are exemplary and are
not intended to be limiting.
[0302] Each of the individual variations described and illustrated
herein has discrete components and features which may be readily
separated from or combined with the features of any of the other
variations. Modifications may be made to adapt a particular
situation, material, composition of matter, process, process act(s)
or step(s) to the objective(s), spirit or scope of the present
invention.
[0303] Methods recited herein may be carried out in any order of
the recited events which is logically possible, as well as the
recited order of events. Furthermore, where a range of values is
provided, every intervening value between the upper and lower limit
of that range and any other stated or intervening value in that
stated range is encompassed within the invention. Also, any
optional feature of the inventive variations described may be set
forth and claimed independently, or in combination with any one or
more of the features described herein.
[0304] All existing subject matter mentioned herein (e.g.,
publications, patents, patent applications and hardware) is
incorporated by reference herein in its entirety except insofar as
the subject matter may conflict with that of the present invention
(in which case what is present herein shall prevail). The
referenced items are provided solely for their disclosure prior to
the filing date of the present application. Nothing herein is to be
construed as an admission that the present invention is not
entitled to antedate such material by virtue of prior
invention.
[0305] Reference to a singular item, includes the possibility that
there are plural of the same items present. More specifically, as
used herein and in the appended claims, the singular forms "a,"
"an," "said" and "the" include plural referents unless the context
clearly dictates otherwise. It is further noted that the claims may
be drafted to exclude any optional element. As such, this statement
is intended to serve as antecedent basis for use of such exclusive
terminology as "solely," "only" and the like in connection with the
recitation of claim elements, or use of a "negative" limitation.
Unless defined otherwise, all technical and scientific terms used
herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs.
[0306] This disclosure is not intended to be limited to the scope
of the particular forms set forth, but is intended to cover
alternatives, modifications, and equivalents of the variations
described herein. Further, the scope of the disclosure fully
encompasses other variations that may become obvious to those
skilled in the art in view of this disclosure. The scope of the
present invention is limited only by the appended claims.
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