U.S. patent application number 16/192781 was filed with the patent office on 2019-05-16 for devices and methods for intrabody surgery.
The applicant listed for this patent is Pavel V. Efremkin. Invention is credited to Pavel V. Efremkin.
Application Number | 20190142453 16/192781 |
Document ID | / |
Family ID | 66431514 |
Filed Date | 2019-05-16 |
![](/patent/app/20190142453/US20190142453A1-20190516-D00000.png)
![](/patent/app/20190142453/US20190142453A1-20190516-D00001.png)
![](/patent/app/20190142453/US20190142453A1-20190516-D00002.png)
![](/patent/app/20190142453/US20190142453A1-20190516-D00003.png)
![](/patent/app/20190142453/US20190142453A1-20190516-D00004.png)
![](/patent/app/20190142453/US20190142453A1-20190516-D00005.png)
![](/patent/app/20190142453/US20190142453A1-20190516-D00006.png)
![](/patent/app/20190142453/US20190142453A1-20190516-D00007.png)
![](/patent/app/20190142453/US20190142453A1-20190516-D00008.png)
United States Patent
Application |
20190142453 |
Kind Code |
A1 |
Efremkin; Pavel V. |
May 16, 2019 |
DEVICES AND METHODS FOR INTRABODY SURGERY
Abstract
A method for conducting intrabody surgery by means of a surgical
device having a cutting arrangement actuated by a driveshaft and
rotationally supported by the guide wire. A receiving cannel
extends through the cutting arrangement and movably receives the
guidewire. A plurality of sensors is provided within the cutting
arrangement to emit signals capable of changing parameters
depending on the composition of the occlusion, so as to allow the
control unit to generate signals controlling operation of the
cutting arrangement. The method includes the steps of detecting
parameters within the intrabody area by the sensors to controlling
operation of the cutting arrangement with the power and control
unit.
Inventors: |
Efremkin; Pavel V.;
(Ardsley, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Efremkin; Pavel V. |
Ardsley |
NY |
US |
|
|
Family ID: |
66431514 |
Appl. No.: |
16/192781 |
Filed: |
November 15, 2018 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
62586654 |
Nov 15, 2017 |
|
|
|
62680260 |
Jun 4, 2018 |
|
|
|
Current U.S.
Class: |
606/7 |
Current CPC
Class: |
A61B 2017/00323
20130101; A61B 2018/00875 20130101; A61B 2217/005 20130101; A61B
2018/00422 20130101; A61B 2017/00022 20130101; A61B 2018/00791
20130101; A61B 2090/08021 20160201; A61B 2217/007 20130101; A61N
2007/0065 20130101; A61B 2017/00685 20130101; A61N 7/02 20130101;
A61B 17/320758 20130101; A61B 2018/00577 20130101; A61B 2017/320069
20170801; A61B 2017/320775 20130101; A61B 2018/00642 20130101; A61B
2017/00544 20130101; A61B 2018/00601 20130101; A61B 2018/00702
20130101; A61N 7/00 20130101; A61N 2007/0043 20130101; A61B 17/2202
20130101; A61B 18/1492 20130101; A61B 2017/320716 20130101; A61B
18/1206 20130101; A61B 18/26 20130101; A61B 2017/22024 20130101;
A61B 17/320068 20130101; A61B 2018/00511 20130101; A61B 18/245
20130101; A61B 2218/007 20130101; A61B 2018/00904 20130101; A61B
2017/22094 20130101; A61B 2017/306 20130101; A61N 2007/0039
20130101; A61B 2018/00505 20130101; A61B 2017/003 20130101; A61B
2017/22042 20130101; A61B 2017/32007 20170801; A61B 2018/0066
20130101 |
International
Class: |
A61B 17/3207 20060101
A61B017/3207; A61B 18/24 20060101 A61B018/24; A61B 18/14 20060101
A61B018/14; A61B 17/32 20060101 A61B017/32 |
Claims
1. A device for intrabody surgery, comprising, a hollow guide wire
and a cutting arrangement provided to drill away calcified
occlusions in the blood vessel with rotatable driveshaft guided by
the guide wire; wherein the guide wire is formed as a hollow tube
having a plurality of openings along a distal end thereof to
facilitate aspiration; the guide wire is used as a conduit for
aspiration of occlusion debris produced by the cutting arrangement,
and wherein the cutting arrangement is formed with a plurality of
apertures enabling debris to be aspired through the apertures into
the openings in the guide wire.
2. A device claim 1, further comprising a hollow guide wire having
one or more openings along the distal end to facilitate aspiration
adapted to aspire and remove debris of occlusion or embolus in the
blood vessel.
3. A device claim 1, further comprising a surgical catheter and a
sliding member having a spring type mechanism positioned at a
distal end of the catheter with a sliding member adapted to move
back and forth under pressure to enforce a contact with the
occlusion, so as to facilitate catching of the occlusion debris and
channeling said debris for aspiration.
4. A device of claim 3, wherein the surgical catheter is provided
for destruction of an occlusion in a blood vessel.
5. A method for conducting intrabody surgery by means of a surgical
device, the surgical device comprising a cutting arrangement
actuated by a driveshaft and rotationally supported by the guide
wire, a receiving cannel extends longitudinally/along a
longitudinal axis passing through the central part of the cutting
arrangement body and is adapted to movably receive the guide wire
there through, a plurality of sensors provided within the cutting
arrangement to emit and receive various types type of signals
(optical, electromagnetic, acoustical, capacitance measuring)
capable of changing parameters depending on the composition of the
occlusion, so as to allow the control unit generates signals
controlling operation of the cutting arrangement, said method
comprising the steps of: detecting one or more parameters within
the intrabody area with said sensors and controlling operation of
the cutting arrangement with the power and control unit, wherein
rotational characteristics of the cutting arrangement are adjusted
based on said parameters detected by said sensors.
6. The method of claim 5, wherein the apparatus further comprises a
detecting arrangement selected from the group consisting of
photoelements, photoresistors and photodiodes, and wherein the
method further comprises the steps of: using said detecting
arrangement, detecting a predetermined condition within the
interbody area; when said predetermined condition is detected at
said detecting arrangement generating a signal directed to the
power and control unit; and responsive to receipt of said signal
directed to said power and control unit, producing a correcting
signal directed to the control unit to adjust performance of the
burr.
7. The method of claim 5, wherein said sensors located within at
the distal end of the burr are able to determine physical and
chemical composition of the occlusion, wherein the computer or
microchip associated with the control unit receives and analyzes
information/data obtained by the sensors and generates signals to
adjust parameters of the power source to optimize speed of rotation
of the burr and ultimately optimizes destruction of an occlusion in
the intrabody area.
8. The method of claim 6, wherein the control unit analyzes
information/data obtained by the sensors and generates signals to
adjust parameters of the power source to optimize rotational speed
and temperature characteristics of the burr.
9. The device of claim 1, wherein the burr is mounted at the end of
a flexible drive shaft which transmits torque from a
torque-generating device (such as an electric or pneumatic motor),
the drive shaft is guided by and surrounds a substantial portion of
the hollow guidewire; and multiple ports are formed within the
front portion of the burr passing through its body to provide
communication between an exterior surface of the burr and a
receiving channel.
10. The device of claim 9, wherein the ports provide communication
between the exterior cutting exterior surface engaging the
occlusion and the apertures of the guide wire disposed within the
receiving channel.
11. The device of claim 1, wherein said cutting arrangement is
selected from the group comprising: a burr or a plurality of blades
rotated by a drive shaft transmitting rotational energy from a
power source; sources of high intensity acoustic or ultrasound
waves; laser energy or other light energy sources; sources of
radiofrequency (RF) energy.
12. The device of claim 1, wherein said cutting arrangement
comprises a plurality of acoustic or ultrasound electrodes focused
into occlusion, said electrodes forming a grid of multitude of
acoustic wave sources.
13. A guidewire for a device for intravascular surgery, comprising
a hollow tubal design in such a way that operator can remotely from
the proximal end manipulate and/or bend the distal area of the
guide wire to an optimum angle thus targeting it into a required
direction within the patient body lumens.
14. The device of claim 13, wherein the action is achieved by
pulling a string attached to the distal end of the guide wire from
outside and which then enters into the internal hollow part of the
guide wire through a hole located at predetermined optimal distance
from the distal point of a guide wire.
15. The device of claim 13, wherein the action is achieved by a
stiffening mandrel or a specially shaped object that can be
inserted through the bore or lumen of a tubular/hollow guide wire
to cause a corresponding bend in the tubular guide wire.
16. The device of claim 13, wherein the guidewire that has at the
distal end a section bended at the lesser than 90-degree angle to
the preceding section of the guide wire with such bended section to
be designed to facilitate guidewire entering and passing through
difficult vasculature.
17. The device of claim 16, wherein where said section has
approximately 2 mm to 30 mm in length.
18. The device of claim 17, wherein said section is spring type
resilient so that it keeps its form but easily allow the catheter
arrangement to passover the bended area when needed.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority of Provisional
Patent Application Ser. No. 62/586,654 filed by the Applicant on
Nov. 15, 2017 and of Provisional Patent Application Ser. No.
62/680,260 filed by the Applicant on Jun. 4, 2018, the entire
disclosure of these applications is hereby incorporated by
reference.
FIELD OF THE INVENTION
[0002] The devices and methods of the invention generally relate to
intrabody surgery and to treatment of occluded body lumens. In
particular, the present devices and methods relate to removal of
the occluding material from the blood vessels as well as other body
lumens.
BACKGROUND OF THE INVENTION
[0003] The devices and methods of the invention are applicable for
various types of intrabody surgery including, but not limited to
cutting, breaking, coagulation, vaporization of any body tissue
(including but limited to Soft tissue includes tendons, ligaments,
fascia, skin, fibrous tissues, fat, and synovial membranes; and
muscles, nerves and blood vessels (which are not connective tissue)
as well as hard tissue/bone and connective tissue) which involves
reaching the targeted tissue through body channels including but
limited to blood vessels, ureter, oesophagus, stomach and duodenum
(esophagogastroduodenoscopy), small intestine (enteroscopy),
largeintestine/colon (colonoscopy, sigmoidoscopy) or incision or
cut through the body tissues (laparoscopic surgery).
[0004] Although devices and methods for removal of the occluding
material from the blood vessels as well as other body lumens are
discussed below in greater detail, it should be absolutely clear
that this is one of many possible applications of the invention. In
fact, devices and methods of the invention are applicable to many
types of intrabody surgery, as identified above.
[0005] Cardiovascular diseases frequently arise from the
accumulation of atheromatous material on the inner walls of
vascular lumens, particularly arterial lumens of the coronary and
other vasculature, resulting in a condition known as
atherosclerosis. Atheromatous and other vascular deposits restrict
blood flow and can cause ischemia which, in acute cases, can result
in myocardial infarction or a heart attack. Atheromatous deposits
can have widely varying properties, with some deposits being
relatively soft and others being fibrous and/or calcified. In the
latter case, the deposits are frequently referred to as plaque.
Atherosclerosis occurs naturally as a result of aging but may also
be aggravated by factors such as diet, hypertension, heredity,
vascular injury, and the like.
[0006] Atherosclerosis can be treated in a variety of ways,
including drugs, bypass surgery, and a variety of catheter-based
approaches which rely on intravascular widening or removal of the
atheromatous or other material occluding the blood vessel.
Particular catheter-based interventions include angioplasty,
atherectomy, laser ablation, stenting, and the like. For the most
part, however, this can be difficult or impossible in tortuous
regions of the vasculature. Moreover, the catheters used for these
interventions are introduced over a guidewire, and the guidewire is
placed across the lesion prior to catheter placement. Initial
guidewire placement can be equally difficult if the lesion is total
or near total, i.e. the lesion occludes the blood vessel lumen to
such an extent that the guidewire cannot be advanced across the
lesion.
[0007] Occlusion in a blood vessel can be caused by a variety of
materials from hard bone like calcium deposits to soft blood clot
or piece of fatty deposit. Multiple type occlusions may be present
in the same vessel. Currently different tools are used to remove
different types of occlusion. Surgeons may need to remove one type
of catheter and replace it with another one in order to work with
different occlusion types. This extends treatment time,
substantially raises cost, and increase risk for a patient. The
inventions provide a more optimal and complete solution to this
problem which include means to analyze the type of occlusion
material present and then adapt the function of the occlusion
removal device accordingly. Furthermore, the invention provides a
combinational arrangement which enables sergeants to successfully
work with different occlusion types without the need to remove one
type of catheter/cutting tool and replace it with another one.
[0008] In prior art, there are known rotational atherectomy systems
utilizing diamond drill tips/burrs to sand-hard calcified
occlusions to very small particles. While there are some
discussions that the particles produced from 20 .mu.m
diamond-tipped burr that ablates plaque into micro-particles are
smaller in size (.about.5 .mu.m) than a red blood cell (8 .mu.m),
it is also known that larger particles of debris, produced when
occlusion is being broken, are generated. Such larger particles can
block blood capillaries and cause serious side effects. However,
even when the occlusion particles are as small as blood cells,
their presence in the blood stream may present a potential risk.
Especially if such particles are accumulated at the essential body
tissues, causing malfunctioning of the vital body organs. Visible
accumulation of even smaller particles, for example tattoo ink
particles (less than 1 .mu.m.sup.(9)), is well known. The tattoos
particles accumulation (tattoo) is well known to be permanent or at
least long term. Since the tattoo ink is inserted into the skin, it
mostly stays in the dermis. Thus, impact of the ink particles on
other tissue and organs is localized. On the other hand, since the
particles generated during the occlusion destruction can be carried
out through the blood stream to the vital body organs, proper
management of such become important. Some of the rotational
atherectomy catheters have built-in arrangements with active
aspiration to remove debris from the blood stream and evacuate the
debris through the catheter. However, these aspiration (debris
evacuation) arrangements are not optimally designed to remove all
or most of such debris particles. The inventions propose more
optimal and complete solutions to this problem.
[0009] The prior art solutions for removal of calcium plaque are
often provided with forwardly shaped rotational drills. Such design
presents a risk of accidental perforation of the blood vessel walls
if such drill is pushed against the wall during the procedure. One
of the aspects of the invention provides ways to limit such risks
of vessel wall perforation as well as minimizes negative aspects of
the procedure on any adjacent tissue.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] In the following drawings, the same parts in the various
views are afforded the same reference designators. Referring now to
the drawings which are provided to illustrate and not to limit the
invention, wherein:
[0011] FIG. 1 is a diagram illustrating a burr or cutting tool
according to one embodiment of the invention;
[0012] FIG. 1A is a diagram further illustrating of the embodiment
shown in FIG. 1;
[0013] FIG. 2 is a diagram illustrating the system of the
invention;
[0014] FIG. 3 illustrates a distal end of a catheter including a
slidable sleeve in an extended position according to another
embodiment of the invention;
[0015] FIG. 4 illustrates the slidable sleeve in a retracted
position according to a further embodiment of the invention;
[0016] FIG. 5 illustrates another embodiment of the slidable
sleeve;
[0017] FIG. 6 is a diagram illustrating one position of the
embodiment combining the burr and the slidable sleeve;
[0018] FIG. 7 is a diagram illustrating another position of the
embodiment shown in FIG. 6;
[0019] FIG. 7A is a diagram illustrating a further position of the
embodiment shown in FIG. 7;
[0020] FIG. 8 illustrates an embodiment of the invention including
a rotatable blade;
[0021] FIG. 9 is a diagram illustrating an embodiment of the
invention utilizing ultrasound energy;
[0022] FIG. 10 is a section view of the embodiment shown in FIG.
9;
[0023] FIG. 11 is a view of a modified embodiment showing the
slidable sleeve:
[0024] FIG. 12 is a section view of the embodiment shown in FIG.
11;
[0025] FIGS. 13 and 14 are diagrams illustrating still another
embodiment of the invention utilizing RF energy;
[0026] FIG. 15 illustrates an embodiment of the invention utilizing
a rotatable blade assembly;
[0027] FIG. 16 illustrates one embodiment of the invention
utilizing a stiffening mandrel or wire;
[0028] FIG. 17 illustrates an embodiment utilizing a pulling string
or wire; and
[0029] FIG. 18 illustrates another embodiment utilizing a
stiffening mandrel or wire.
DETAILED DESCRIPTION OF THE INVENTION
[0030] As used herein in the description of various components,
"proximal" refers to a direction toward the system controls and the
operator, and "distal" refers to the direction away from the system
controls and the operator and toward a terminal end of the cutter
assembly.
[0031] In general, the material removal system of the present
invention comprises a control unit attached to one end of a
catheter assembly and an axially translatable, rotatable drive
shaft, with a cutter assembly positioned at the distal end of the
drive shaft at least partially supported by the guidewire. The
material removal system of the invention further comprises multiple
sensors positioned at the cutter assembly area and along the length
of the catheter. In one embodiment the system includes wires
associated with sensors to deliver electric power to ultrasound or
RF emitters.
[0032] The cutter assembly is translated over a guidewire to the
material removal site and is actuated at the material removal site
to cut, grind or ablate, or otherwise remove, the occlusive
material. The control unit, and manifold assembly remain outside
the body during a material removal operation.
[0033] We are referring now to FIG. 1 illustrating a catheter
assembly 10 of one embodiment of the invention provided for passing
a high-rotational-speed burr/cutter 20 into blood vessels as well
as to other bodily cavities and adapted to ablate and remove
abnormal occlusions and deposits. The, burr/cutter 20 actuated by a
driveshaft 30 and guided through the vessel to the application area
by the guidewire 50, drills away the occlusions in the blood
vessel.
[0034] The flexible guidewire 50 is navigated through one or more
lumens such as blood vessels, to a desired material removal site.
The catheter assembly 10 generally houses the burr/cutter 20, drive
shaft 30, which also defines a lumen 32 for the aspiration and/or
infusion of fluids. It will be also discussed in the application
that a gap between a protective sheath of the catheter and the
drive shaft is utilized for the aspiration and/or infusion of
fluids. The catheter assembly 10 may be fixed to and advanced in
concert with the drive shaft 30 to actuate a cutter assembly. The
guidewire 50 and the catheter assembly 10 are introduced into a
lumen of a patient and navigated or guided to the site of the
desired material removal operation.
[0035] A proximal end 33 of the drive shaft is operably connected
to vacuum or infusion pumps, while a distal end 34 of the drive
shaft is operably connected to cutter/burr 20. Drive shaft 30 is
preferably a flexible, hollow, helical, torque-transmitting
shaft.
[0036] The burr/cutter 20 is formed having teardrop-shaped head 22
with a front diamond tipped working portion/surface 24 facing the
occlusion and a rear portion. A cylindrical connecting element 35
extends from the rear portion in the proximal direction for
connection to the distal end of the catheter. As will be discussed
later in the application, optionally a stop member 37 can be
provided at the proximal end of the connecting element.
[0037] The head 20 is formed with a plurality of cutting flutes 36
and a plurality of ports 38 providing for aspiration and/or
infusion. As illustrated in FIG. 1, the burr/cutter has a central
bore 40 that is larger than outer diameter of the guidewire 50, so
that drive shaft 34 with the cutter 20 are slidable and easily
translatable over guidewire 50. The cutting flutes/grooves 36 are
formed with sharp blades 42 along the edges defining outer cutting
surfaces. Cutting flutes 36 may have sharpened edges to provide
cutting and ablation. The cutting edges are arranged to direct
debris produced during the cutting operation to the inferior the
head 20 through the respective ports. Cutting flutes 36 may,
additionally or alternatively, have an abrasive or cutting material
bonded to one or more surfaces. A distal end portion 26 of the
cutter/burr, may additionally or alternatively be provided with
abrasive or cutting material. Material such as diamond grit is an
example of suitable abrasive.
[0038] In one embodiment of the invention at least two cutting
flutes 36 are arranged in a radially symmetrical configuration. In
another embodiment at least one cutting flute is asymmetrically
arranged regarding a longitudinal axis of the head 22.
[0039] Cutting flutes 36 are separated from one another by
depressions 44 formed with multiple ports 46 providing passage of
debris from the exterior of cutter/burr to the central bore 40
forming an internal cavity 48.
[0040] The central bore 40 forming the internal cavity 48 extends
longitudinally/along a longitudinal axis passing through the
central part of the burr/cutter body and is adapted to movably
receive the guide wire 50. The cutter/burr 20 is mounted at the
distal end 34 of a flexible drive shaft 30 which transmits torque
from a torque-generating device, such as an electric or pneumatic
motor. The drive shaft 30 is guided by and surrounds a substantial
portion of the hollow guidewire 50.
[0041] In the preferred embodiment ports/openings 46 are formed
within the front portion 24 of the cutter/burr passing through its
body, to provide communication/passage between the exterior surface
and the internal cavity 48. More specifically, the ports/openings
46 provide communication between the cutting exterior surface 28
engaging the occlusion with the internal cavity 48 and also provide
communication with the apertures/ports 54 of the guide wire 50
disposed within the cavity 48.
[0042] Particles resulted from operation of the burr/cutter 20 are
properly removed to prevent penetration of the particles into a
blood stream passing through the vessel. Debris particles resulted
from operation of the burr/cutter 20 are drawn through the ports 46
into internal cavity 48 by low pressure zone created in internal
cavity by the vacuum pump connected to the distal end of the drive
shaft. The ports 46 also allow debris produced during the operation
of the burr 20 to be aspired into the ports 54 in the guide wire.
It will be discussed in greater detail below that the guide wire 50
made as a hollow tubular structure is also used as a
suction/aspiration conduit for aspiration of occlusion debris
produced, as the burr/cutter 20 drills away the occlusion. In an
alternate embodiment, the ports 46 can be also provided within the
rear portion 25 of the burr. The guide wire can be removed after
the burr/cutter 20 is guided within the body lumen to the
occlusion. Thus, the entire internal cavity 48 of the burr and the
lumen 32 of the shaft can be used for aspiration purposes.
[0043] The front working portion/surface 24 of the cuter facing the
occlusion may have coatings on its inside or outside for various
purposes, for example, for protection against corrosion by body
fluids or for insulation against the high energy emitted towards
its distal region. It can be of any dimension convenient for its
intended use.
[0044] Additional structures at the front working portion/surface
24 may help prevent clogging of the suction conduit. For example, a
filter, a screen, a mesh, a shield or other barriers can be
provided at the distal region of the suction conduit.
[0045] In one embodiment of the invention the guidewire 50 is
formed as a hollow tube. The drive shaft 30 is also hollow. The
particle-entrained blood can flow from the burr 20 through the
fluid ports 46 into the bore 40 and interior cavity 48 facing the
guide wire 50 which is at least partially disposed within the
hollow drive shaft 30 connected to a suction or injection
devices.
[0046] The hollow tube or central passage 52 of the guide wire 50
is used as a conduit for aspiration of occlusion debris. As
illustrated, the guidewire 18 includes a plurality of
openings/ports 54 along its distal end 56. Use of such hollow guide
wire enables a clinician to catch occlusion debris more
efficiently. This is because, the openings/ports 54 allow to
catch/collect debris right at the site, where they are produced in
the surgical procedure and before being disbursed. The hollow
guidewire 50 can be made from metal, or plastic, or grafine or any
other material which meets requirement for guide wire and is not
permutable for liquid that contains debris of occlusion or
embolus.
[0047] The hollow/tubular guidewire 50 if needed, is also capable
of delivering fluid/medication/coolant to a target location. With
ports 54 liquid/fluid/medication is allowed to leak from the hollow
passage 52 out into the vasculature passageway. The location of
discharge of liquid/medication/coolant from the tubular guide wire
50 can be controlled by controlling size of the openings/ports 54
as well as the location thereof. In addition, a resilient/polymer
sleeve may be inserted in the lumen or bore of a tubular guide
wire, and/or on the outside as well, for sealing and preventing the
outflow or discharge of liquid/fluid/medication from the guide wire
lumen. Controlling the length of such sleeves on the guide wire 50
enables control of discharge points of liquid/medication/coolant
from the guide wire. Furthermore, the exterior sleeve also provides
better engagement/seal between the wire and the interior of
vasculature, to assure proper position of a catheter inside the
lumen walls. The space between the drive shaft and protective
sheath may be also used to receive and deliver
lubrication/cooling/medication liquids.
[0048] Further important functionality of the ports 54 of the
hollow guide wire 50 will become applicable when used in
combination with the ports 45 formed in the cutting burr 20.
[0049] As to the aspiration aspect of the invention, a vacuum pump
70 (see FIG. 2) creates a low-pressure zone at the proximal end 33
of the drive shaft and the hollow guide wire and/or to aspirate
debris of occlusion or embolus in the blood vessel or body lumen
produced by the ablation tip.
[0050] Controllable entry of the cutter/burr 20 into calcified
occlusions/obstructive lesion has to be assured for its predictable
advancement. Thus, to facilitate such cutting tool advancement, the
drive shaft 30 should be axially translatable with respect to guide
wire 50. In the current prior art practice to initiate evacuation
of residual debris. In this often complicated and time-consuming
technique/procedure, the tool similar to the burr/cutter 20 is
nudged into a calcified occlusions area during rotation and then
retracted. This manipulation in the prior art procedure permits
evacuation of residual debris and to reestablish local circulation
before making another cutting cycle on the lesion. On the other
hand, in the present invention the ports 46 in the body of the
burr/cutter 20 establish a reliable communication between the burr
cutting blades 42, the hollow passage 52, and the ports 54 of the
guide wire. In this manner residual debris are evacuated
continuously during the procedure without the need for the
complicated manipulations discussed above.
[0051] Although the cutter/burr 20 has been discussed above for the
removal of the occluding material from the blood vessels, it should
be noted that application of the burr to many types of the
intrabody surgery (as identified above) also foil is a part of the
invention. For example, in the ureteroscopy procedure, which treats
and removes stones in the kidneys and ureters, the burr 20 may be
used in combination with the respective flexible scope. In the
procedure doctor passes the scope with the burr through patient
bladder and ureter into kidney. Use of the burr 20 may be
especially applicable for larger stone removal and can be combined
with other techniques and/or tools including energy-based devices
to break stones up. Use of the burr 20 may be also applicable in
the ureteroscopy for the removal of polyps, tumors or abnormal
tissue from a urinary tract. Further application of the burr 20 is
in percutaneous nephrolithotomy or percutaneous nephrolithotripsy,
combined with a small tube to reach the stone, the burr
grinds/breaks the stone up. This action can be combined with the
use of high-frequency sound waves, radio frequency or other
energy-based devices. After the procedure the pieces of a stone are
vacuumed up and removed from the system with a suction arrangement
of the invention.
[0052] The control unit 12 preferably comprises a base arranged so
that the control unit may be stably supported on a work surface or
a body surface during material removal operations. The control unit
12 also preferably incorporates control systems for actuating,
adjusting and providing system information concerning power, drive
shaft rpm, drive shaft axial translation, aspiration, infusion and
the like.
[0053] As illustrated in FIG. 2 the control unit 12 houses a
programmable logic controller and power source 15 in operable
communication to provide power and to control operation of various
units of the system of the invention. The control unit may include,
but not limited to vacuum control unit, cutter advancer unit,
guidewire control unit, cutter assembly drive control, and
aspiration and infusion control unit. The control unit 12 also
controls a block providing information concerning operating
conditions and feedback from the material removal site to the
operator. According to one embodiment, control unit 12 utilizes
inputs received from multiple sensors 16 located at the burr/cutter
20 and/or other critical regions of the catheter assembly to
continuously updated output to an operator including such operating
parameters as temperature at the material removal site; cutter
assembly rotation rate and/or advance rate; aspiration rate and/or
volume; infusion rate and/or volume; and the like. Control unit 12
may additionally provide adjustable controls permitting the
operator to control operating parameters of the cutter assembly and
material removal operation.
[0054] As illustrated in FIG. 2, the control unit 12 is provided to
regulate the energy/power source 15 for the optimum output level
based on type and characteristics of the targeted occlusion (hard,
soft, blood, etc.) and/or characteristics of the burr catheter
(length, diameter, temperature, etc.). Characteristics of the
control unit 12 may be adjusted by the operator or automatically
based on inputs from the sensors. Controlling various
characteristics/parameters at the operation cite are based on the
information provided by sensors positioned at the distal end of the
catheter and the burr, such as for example speed of rotation,
temperature, etc.
[0055] Such characteristics can be manually or automatically
adjusted based on the signals and data received from the sensors 16
installed within the cutter/burr 20.
[0056] Detectors/Sensors 16, 18 may emit and receive various types
of signals (optical, electromagnetic, acoustical, capacitance
measuring) that will change parameters depending on the composition
or other physical properties of the occlusion and/or tissue
surrounding occlusion and/or physical characteristics of the
catheter itself, so as to allow the control unit 12 to calculate
and generate proper signals controlling operation/speed of
rotation, etc. of the burr 20.
[0057] Detectors/Sensors 16 located at the distal end of the burr
20 are able to recognize (determine) the physical and chemical
properties of the occlusion. A computer or microchip 14 associated
with the control unit 12 receives and analyzes information/data
obtained by the sensors and generates signals to adjust parameters
of the power source to optimize the destruction of an occlusion in
the blood vessel and/or to produce other desired effect on targeted
soft tissue. As an example, the control unit 12 analyzes
information/data obtained by the sensors and generates signals to
adjust parameters of the power source to optimize rotational speed,
etc. of the burr 20.
[0058] According to one embodiment of the invention, sensors 16 are
capable of detecting the level of hardiness/calcification,
water/moisture content, etc., within the material of an occlusion.
As the burr 20 passes through various zones/sections/areas of the
occlusion, optimal levels of rotational speed, etc. can be achieved
for each zone of treatment. For example, a higher speed of rotation
can be provided for the destruction of calcinated occlusion having
higher degree of hardiness. On the other hand, lower speed will be
generated for the areas with softer occlusion materials.
[0059] Utilization of the cutting burr 20 of the invention is also
accompanied by automatic target feedback, thermal feedback for
example, to precisely control the speed of rotation, etc. This is
needed to prevent damage to surrounding tissue. For this purpose,
non-contact thermal detectors 19 (to be shown) can be provided. The
output of the non-contact, thermal detectors 19 can be used to
adjust the output of the power source 15 to maintain selected
characteristics including temperature at the treatment site.
[0060] In the invention to effectively control the destruction of
the occlusion, a condition of the entire artery body and/or the
tissue surrounding the operation site is monitored by the detector
17 adopted to detect irradiation reflected from such tissue. One of
the essential functions of the detector 17 is to control the effect
of the drilling/ablation on the tissue surrounding the site. In
every individual case, a doctor sets specific rotational, etc.
characteristics to produce the required effect. If a situation at
the operation site becomes unfavorable, for example the temperature
exceeds predetermined limits, the detector 17 generates a signal
directed to the control unit 80, which in turn produces a
correcting signal to the power source 15 or to the control unit
12.
[0061] The computer or microchip 14 of the control unit 12 receives
and analyzes the information obtained by the detector 17 and to
generate a control signal to adjust parameters of the power source
15 in such a way as to optimize the destruction of an occlusion in
the blood vessel or other desired effect on targeted soft
tissue.
[0062] In an alternate embodiment the control signal generated by
the thermal detector 17 energizes the cooling arrangement (see
above) to directly or indirectly lower/adjust temperature at the
site. This is necessary to exclude possibility of damaging an
adjacent tissue. The detector 17 and the sensors 16 can be made
utilizing a wide variety of photoelements, photoresistors,
photodiodes and similar devices.
[0063] As discussed above, frictional forces resulted from the
engagement/drilling between the burr 20 and the material of the
occlusion, as well as other factors may result in temperature
elevation of the surrounding tissue. In the invention, the
temperature elevation occurs controllably without causing
irreversible thermal damage to the surrounding tissue of the
arteries. The control unit 12 adjusts the energy to maintain a
pre-selected target temperature at the site/spot. In one embodiment
of the invention, to maximize patient safety, an optional
continuous or pulsed cooling device can be provided to deliver a
coolant from the infusion material storage 55 by means of the
infusion pump 53 through the hollow guide wire 50 to the operation
site during or after the surgical procedure.
[0064] The diagram of FIG. 2 schematically depicts a system
according to one embodiment of the present invention that may be
connected to the cutter 20 to evacuate the ablated or cored bodily
material from a subject's vascular system using various embodiments
of the cutter/burr 20. The vacuum pump 70 provided at the proximal
end of the system creates a low-pressure zone resulted in suction
pressure within the hollow inner space of the drive shaft and the
guide wire 50 to evacuate cut and/or ablated bodily material
directly from the operating site in the vascular system.
[0065] In another embodiment, the vacuum pump 70 is interconnected
to a pulse modulator 71, the actuation of which creates one or more
pressure differentials to the aspiration system. Accordingly, in
this embodiment rather than creating a constant suction pressure
within the system to evacuate cut and/or ablated bodily material
from a subject's vascular system, the aspiration system of the
invention applies alternative pressure(s), thereby creating pulses
of suction pressure within the lumen. Utilizing a series of
constant and/or varying pressure pulses is potentially beneficial
in aspirating bodily material, particularly when aspirating larger
cylindrically looking core or plug like shapes of bodily
material.
[0066] Aspirated liquid and/or particle from an area near distal
end of the tool are accumulated and stored in the disposable debris
storage 76. A filter 74 can be also provided upstream of system for
filtering debris and aspirated bodily material and also for
providing visual feedback to a user related to the type, quantity,
and flow rate of material being removed from a patient. The debris
collection container 76 may be in fluid communications with the
vacuum pump 70 and may include one or more known devices for
collecting and filtering materials removed from a patient. The
container 76 may have transparent sidewalls for providing visual
feedback to a user regarding flow-rate, content, coloration, etc.
Those of skill in the art will appreciate that various types of
collection containers may be used. The collection container 76
and/or filter 74 may also comprise one or more custom filter
features with various mesh sizes, capacities, etc. based on the
specific application.
[0067] The distal end 56 of the hollow guide wire 50 functioning as
a suction conduit can be made of a variety of flexible or rigid
materials or a combination of both, such as stainless steel or
plastics. Still further, the distal end 56 of the guide wire formed
as a suction conduit can be made of a material different from the
body of the hollow guidewire. For example, one might want to make
the distal end 56 with a more heat-resistant material to withstand
high energy directed to it. It may also be desirable to use a more
impact-resistant material to withstand the initial impact from the
solid particles drawn by the suction force.
[0068] We are referring now to FIG. 3, showing an expanded/working
position of a sliding sleeve 60 according to another embodiment of
the invention. As illustrated, the distal end of the catheter
assembly 10 is provided with the sliding sleeve 60 having an
activating mechanism 62 provided for controllable movement of the
sleeve back and forth along the catheter. In one embodiment of the
invention the activating mechanism 62 is spring controlled.
However, the activating mechanism 62 can be energized/actuated in
any conventional manner, such as for example electrical, pneumatic,
etc. mechanisms are contemplated. The front, distal end 65 of the
sleeve 60 is designed to arrange a tight contact between the
catheter and the occlusion. This significantly enhances catching
the occlusion debris and channeling them into the hollow tubular
passage 66 for aspiration. As illustrated, in the expanded working
position the sleeve 60 extends outwardly from the exterior surface
of the catheter 10. In this arrangement the diameter of the outer
periphery at the distal end of the catheter is slightly increased.
In the contracted position the sleeve 60 is positioned along the
exterior surface of the catheter.
[0069] In another embodiment, illustrated in FIG. 4, a
circumferential recess 68 is formed within the distal end of the
catheter body having the depth and length corresponding to the
respective dimensions of the sleeve 60. In this embodiment the
exterior surface of the sleeve is in flash with the exterior
surface of the catheter. Prior to the catheter's placement through
the blood vessel lumen to the operation cite, the sleeve 60 is
pressed inwardly in the direction of the proximal end to overcome
resistance of the activating mechanism 62. As a result, the sleeve
60 is submerged within the circumferential recess 68. In this
locked position the exterior of the sleeve 60 is in flash with the
exterior of the catheter. Upon delivery and proper positioning at
the site, the activating mechanism 62 is released-unlocked and the
sleeve 60 is moved to the expanded working position to provide a
tighter contact between the distal end 65 of the sleeve 60 and the
occlusion. The engaging distal end 65 of the sleeve 60 can be made
of are resilient or soft material capable of adopting evolving
configuration of the external part of the occlusion during the
procedure.
[0070] In an alternate embodiment, to further increase resiliency
of the sleeve, as illustrated in FIG. 5, longitudinal slits 67 are
circumferentially arranged within the sleeve body. The slits 67
extend inwardly from the distal end of the sleeve to separate the
sleeve body into a plurality of segments 69. In one embodiment of
the invention distal area of the segments 69 can be curved and/or
formed from a resilient material to further improve engagement with
the occlusion. Any reasonable number and configuration of the slits
are within the scope of the invention.
[0071] Turning now to FIGS. 11 and 12 showing another embodiment of
a sleeve assembly 100 which consists of an external base 102 and an
internal support 104 spaced from each other by a receiving gap 106.
A plurality of separated from each other engaging segments 110 are
positioned in the receiving gap 106 for independent slidable
movement along a longitudinal axis. The base is formed with an
inner cavity 112 extending forwardly from a rear wall 114 and is
adapted to slidably receive the plurality of the engaging segments
110. Any reasonable number of the segments symmetrically positioned
along its longitudinal axis is contemplated. Each engaging segment
consists of at least a front part 116 adapted for engagement with
an occlusion and a rear part 114 adapted for slidable movement
within the inner cavity 112. Each segment 1110 slides within the
inner cavity 112 along the longitudinal axis of the sleeve
independently from other segments. A biasing member or a spring 120
is positioned between the rear end of each segment and the rear
wall of the base. Thus, upon the sleeve approaching the occlusion,
the front parts of each segment which is pressed by the biasing
member, engages a specific configuration of the respective area of
the occlusion independently from other segments. The engaging
distal end of each segment can be made of are resilient or soft
material. In this embodiment the front parts 116 of independently
movable segments are capable of adopting evolving configuration of
the external part of the occlusion. Therefore, the sleeve assembly
provides an improved tighter contact between the front parts of the
segments and the occlusion during the procedure.
[0072] FIG. 6 illustrates yet another embodiment of the present
invention which combines application of the above-discussed
burr/cutter 20 with the sliding sleeve 60 movably positioned at the
rear portion of the burr, which is connected to the distal end of
catheter 10. As illustrated, the sleeve 60 is moved proximally and
is prevented from further motion in this direction by a stop
provided at the at the rear cylindrical portion of the burr. The
hollow interior of the sleeve defines an interior space 64 that
serves as a burr/cutter housing. As shown in FIG. 6 the cutter/burr
20 resides in the interior space 64 when axially retracted in a
proximal direction when the cutting procedure is completed.
[0073] A further position of this embodiment is illustrated in FIG.
7, depicting that the sleeve 60 is moved away from the stop 37
distally to the expanded position and a tight contact between the
distal end 65 of the sleeve and the occlusion is assured. An
abrasive or cutting material is bonded or by any other conventional
means attached to the distal end 65 of the sleeve, forming an
auxiliary cutting region. In an alternate embodiment, a cutting
element or a cutting edge can be formed instead of the abrasive
material. In this manner this embodiment is formed with two cutting
regions, including the burr/cutter 20 and the auxiliary cutting
region.
[0074] By the motion of the catheter the burr/cutter 20 is
delivered through the interior space 64 to the operation site. In
this manner, the cutting tip of the cutter/burr 20 is positioned at
a (predetermined) area of the occlusion, followed by the cutting
process with the burr 20 being rotated by the drive shaft 30.
[0075] Turning now to FIG. 7A a further step in operation of this
embodiment. In the cutting process, to drill away the occlusion the
rotating burr 20 is moved by sliding the catheter in the distal
direction until the stop engages the rear face of the sleeve. Upon
this engagement a locking device locks the sleeve at the rear
portion of the sleeve, so that combined/mutual rotation of the
sleeve and the cutting burr 20 is initiated. In this process a
major central portion of the occlusion is cut or drilled away by
the cutting burr 20. However, in the prior art a portion of the
occlusion along inner walls of the blood vessel or lumen is not
removed due to relatively small outer diameter of the burr. In the
invention, as illustrated in FIG. 7A this part of the occlusion is
removed or cut away by an auxiliary cutting region formed at the
distal end 65 of the rotating sleeve. Thus, application of this
embodiment enables a practitioner to eliminate or cut away the
entire occlusion in one procedural step.
[0076] Furthermore, during the cutting procedure, walls of the
sleeve 60 separate/isolate the cutter 20 from the blood vessel
walls 63. Thus, a risk of accidental perforation of the blood
vessel walls 63 or any other adjacent tissue during the procedure
is minimized. The interior space 64 of the sleeve creates a conduit
which accommodates materials cut during the procedure and improves
the flow of various fluids during aspiration and/or infusion.
[0077] It should be noted that application of the slidable sleeve
60 is not limited to the removal of the occluding material from the
blood vessels. The sleeve 60 can be used in many types of the
intrabody surgery (as identified above). For example, it can be
used in ureteroscopy procedure, which treats and removes stones in
the kidneys and ureters. The sleeve 60 may be used in combination
with the flexible scope, which is passed through patient bladder
and ureter to provide an enhanced contact with kidney. Use of the
sleeve 60 facilitates larger stone removal, combined with a laser,
which passes through the scope to break stones up. Another example
is use of the expandable sleeve 60 in the ureteroscopy for the
removal of polyps, tumors or abnormal tissue from a urinary tract.
Similar to the above discussed manner, the sleeve 60 can be used in
percutaneous nephrolithotomy or percutaneous nephrolithotripsy,
combined with a small tube to reach the stone and break stone up
with high-frequency sound waves or a laser. The broken pieces are
vacuumed up and removed from the system by a suction arrangement of
the invention.
[0078] Although an assembly combining the burr/cutter 20 with the
sliding sleeve 60 has been discussed above, it should be noted that
use of the cutter with other type pf protective devises is within
the scope of the invention. For example, an assembly where the
burr/cutter 20 is combined with the sleeve arrangement illustrated
in FIGS. 11 and 12 is also contemplated.
[0079] In a further embodiment of the invention illustrated in FIG.
8, a processing unit 80 with a rotatable blade or cutting element
85 is provided at the distal end of the drive shaft 30 to cut and
macerate the occlusion (embolus) and direct/evacuate cut materials
away from the site.
[0080] The processing unit 80 comprises a chamber 82 rotatably
receiving a drive shaft assembly 84 having a conveying member 86
rotationally positioned thereinside. The conveying member 86 is
adapted to receive the occlusion material cut by the cutting
element 85 and then to transport the material along the chamber
82.
[0081] In the illustrated embodiment, the drive shaft assembly 84
both transports removed or cut tissue in the processing unit 80 and
drives rotation of the cutting element 85. In other embodiments the
drive shaft 84 may transport removed or cut tissue proximally
within the processing unit 80 but may not drive rotation of a
cutting element 85. FIG. 8 shows that the drive shaft assembly 84
is attached to the cutting element 85.
[0082] The drive shaft 84 is generally cylindrical and may comprise
a solid tube or a hollow tube. The drive shaft with the conveying
member 86 is manufactured to be flexible enough to facilitate
navigate navigation through tortuous vessel anatomy and strong
enough to withstand the stresses encountered by high speed
rotation, transmission of torque through the driveshaft to the
cutter 85 at the distal tip of the processing unit 80, and
transport of calcified material. The conveying member 86 may be a
separate element which is attached or affixed in some manner to a
substantially cylindrical drive shaft. Alternatively, the drive
shaft 84 and the conveying member 86 may be forming as a single
unitary element.
[0083] The drive shaft 84 is formed having a central lumen 88.
Since the lumen 88 is used to deliver the guidewire 50, it may be
coated with a lubricious material or made of a lubricious material
to avoid binding with the guidewire. The central lumen 88 of the
shaft 84 may also be used to deliver fluids to the operative site
simultaneously with the guidewire or in place of the guidewire.
[0084] In one embodiment of the invention a plate 95 having a
plurality of holes 97 passing from one face of the plate to the
other is positioned within the chamber 82 transversely to the
longitudinal axis thereof. In this manner, the occlusion material
initially cut by the cutting member 85 is delivered by the
conveying member 86 to the chamber 82 for further processing by
passing through the plurality of holes 97 of the plate 95. Use of
the plate 95 having the plurality of holes 97 is recommended where
highly calcified occlusion is treated by the apparatus of the
invention. The receiving chamber 82 along with the shaft 84 with
the conveying member 86, and the optional plate 97 forms a first
processing section 83 of the unit 80.
[0085] The conveying member 86 may be an auger type system or an
Archimedes-type screw that conveys the debris and material
generated during the procedure away from the operative site. The
conveying member 86 has a raised surface or blade that drives
materials away from the operative site.
[0086] Debris can be evacuated outside the body by the conveying
member 86 action along the length of the catheter and with or
without supplement of the vacuum pump connected to the catheter.
Alternatively, the debris may be accumulated in a reservoir within
the device.
[0087] Optionally, a plurality of generally equally spaced ridges
87, which can be collapsible in nature, can be provided, extending
from an inner wall 89 of the chamber. The ridges 87 tend to provide
sufficient clearance about the conveying member 86. In this manner,
initially processed occlusion materials can be propelled through
the processing unit 80 without development of back pressure due to
clogging in the assembly. The ridges 87 are aligned to increase
material throughput rate by channeling material towards the distal
end of the unit 80.
[0088] As illustrated in FIG. 8, optionally the tool of the
invention can be provided with a second processing section 90. The
second section 90 comprises a second chamber 82' with a second
drive shaft 84' having a conveying member 86' with a second pitch
generally somewhat smaller than the pitch of the first conveying
member 86. The first and second conveying members are co-axially
arranged and formed with a longitudinally extending apertures used
to accommodate, among other functions the hollow guidewire of the
invention. The second section 90 can be optionally provided with a
second plate 95' having a second plurality of holes 97' passing
therethrough from one face thereof to the other. The holes 97' of
the second plate 95' are smaller than the holes of the first
plurality of holes 97. In this manner, as previously discussed, the
occlusion materials are initially processed/ground by passage
through the first plurality of holes 97 under the impetus of the
first conveying member 86. Then, such initially processed/ground
material is further processed/ground to a smaller size by passage
through the second plurality of holes 97' under the impetus of the
second conveying member 86'.
[0089] The second processing chamber can be employed in certain
situations, for example, where highly calcified occlusion is
encountered. In this instance, the material exiting the first
plurality of holes can be in the form of relatively coarse
agglomerations. Such material is then picked up and propelled by
the second screw and the plurality of ridges, so as to help to
guide the material towards the second plate. As the material passes
through the second plurality of holes of the second plate, further
reduction of sizes of the occlusion particles takes place.
[0090] As illustrated in FIG. 8 the processing unit 80 can be
optionally provided with the sleeve 60 slidably arranged at the
exterior part of its body. In the illustrated expanded position,
the sleeve 60 extends outwardly from the distal end of the unit 80.
The hollow interior of the sleeve forms an interior space 64 that
serves as a housing of the cutting element 85. More specifically,
the interior space 64 also accommodate the location where the drive
shaft is attached to the cutting element 85. When the sleeve 50 is
retracted in the proximal direction, the cutting element 85 is
exposed.
[0091] In use when the sleeve 50 is in the expanded working
position the distal end of the sleeve 50 engages the occlusion,
then the drive shaft and the attached cutting element 85 are
delivered through the interior space 64 to the operation site. The
interior space 64 of the sleeve also creates a conduit which
accommodates materials cut during the procedure and to improve the
flow of various fluids during aspiration and/or infusion. In this
embodiment the cutting element 85 is precisely delivered to the
occlusion. Further, the walls of the sleeve isolate the cutting
element 85 from inner surfaces of the blood vessel walls,
minimizing the risk. Thus, a risk of accidental perforation/damage
of the blood vessel walls during the cutting procedure.
[0092] In operation of the processing unit 80, initially the
occlusion material cut by the cutting element 85 is processed is
fed into the chamber 82. The drive shaft assembly 84 having a
conveying member 86 propel the cut occlusion material towards and
through the holes in the plate 95. Thus, size of the initially cut
occlusion materials is reduced to become more adaptable for
suction, collection and disposal as previously discussed. To
further reduce the cut occlusion materials the second processing
chamber may be utilized in the above-discussed manner.
[0093] When light sources 93 are provided at the distal end of the
catheter, the cutter 85 is arranged to minimally block the emitted
light. Light is pulsed in such a way that it pulses when light
outlets 93 are not covered/blocked by cutter 85.
[0094] Application of the processing unit 80 combined with the
cutting element 85 to many types of the intrabody surgery (as
identified above) also forms a part of the invention. For example,
in ureteroscopy procedure, which treats and removes stones in the
kidneys and ureters, the processing unit 80 may be used in
combination with the respective flexible scope. Use of the
processing unit 80 is also applicable for larger stone removal,
combined with a laser, which passes through the scope to break
stones up. Further, in the ureteroscopy the processing unit 80 can
be used for the removal of polyps, tumors or abnormal tissue from a
urinary tract. The processing unit 80 including the cutting element
85 is also usable in percutaneous nephrolithotomy or percutaneous
nephrolithotripsy, combined with a small tube to reach the stone
and break stone up with high-frequency sound waves or a laser.
After the procedure the pieces are vacuumed up with a suction
arrangement of the invention.
[0095] Turning now to FIG. 15 showing a processing unit 180 formed
with a rotatable blade assembly 185 is provided at the distal end
of the drive shaft 134. The rotatable blade assembly 185 includes a
hub 160, a plurality of blades 162 arranged at the hub and an outer
band 164 arranged at outer peripheries of the blades 162. In one
embodiment, the hub, the blades and the outer band can be
integrally formed. Each blade 162 is formed having a leading
cutting edge 168 and a trailing edge 167 and extend in a plane
generally perpendicular to axis of rotation. The outer band 164 has
a front/distal area 166 facing the occlusion and a rear/proximal
area. An abrasive or cutting material is bonded or by any other
conventional means attached to the distal area, forming an
auxiliary cutting region 170. In the alternative, a cutting element
can be formed at the front area of the outer band. Thus, the blade
assembly 185 is formed with two cutting regions, including the
primary cutting region defied by the leading cutting edges 168 of
the blades 162 and an auxiliary cutting region 170 defined the
front/proximal area 169 of the outer band. In use upon approaching
the occlusion, the leading edges 168 of the primary cutting region
remove or cut away a central area of the occlusion. In the prior
art procedures due to smaller outside diameter of the cutting tools
relative to the inner diameter of the blood vessels and other
reasons, an occlusion tissue disposed at the inner surfaces of the
blood vessels often remains unremoved. In the present invention
this tissue of the occlusion, which is adjacent to the inner walls
of the blood vessel, is eliminated or cut away by the auxiliary
cutting region 170. Thus, application of the rotatable blade
assembly of this embodiment enables a practitioner to eliminate or
cut away the entire occlusion in one procedural step. This
embodiment can be used for cutting soft occlusions tissues and is
particularly adapted for application in stent restenosis
procedures.
[0096] Similar to the embodiment of FIG. 8, the processing unit 80
includes a chamber 82 having the drive shaft 184 provided with the
conveying member 186. The drive shaft and the conveying member both
transport removed or cut tissue in the processing unit 80 and drive
rotation of the cutting blade assembly 85'. As illustrated in FIG.
15 the catheter is formed with an exterior sheath spaced from an
inner hollow tube receiving the drive shaft. The drive shaft 84 is
formed having the central lumen 88 used to deliver the guidewire 50
and may be also be used to deliver fluids to the operative site. To
facilitate rotation of the drive shaft lubricant can be delivered
through the space separating the interior of the hollow tube and
the drive shaft.
[0097] The occlusion material cut by the cutting blade assembly 85'
is delivered by the conveying member 86 to the chamber 82 for
further processing as previously discussed in the embodiment of
FIG. 8. Then debris of processed cut material are evacuated through
the space separating the exterior sheath from the inner tube with
or without supplement of the vacuum pump connected to the catheter.
Alternatively, the debris may be accumulated in a reservoir within
the device.
[0098] Turning now to FIG. 9 illustrating still another embodiment
of the invention, wherein a source (generator) of ultrasound energy
is disposed at the proximal end of the catheter. In the illustrated
embodiment the source is in the form of one pair of spaced from
each other ultrasound waive generators provided to generate
ultrasound waves/beams focused on a specific area near the proximal
tip of the catheter. In use the proximal end is delivered to the
occlusion, so that the ultrasound beams are focused within the body
of the occlusion for selective destruction of the occlusion tissue.
Since the focus is separated/spaced from the surrounding vessels,
the risk of collateral damage to surrounding tissue or blood
vessels walls is minimized. Although one pair of cooperating
ultrasound generators is shown, it should be appreciated however
that the distal end of the catheter can be provided with any
reasonable number of cooperating ultrasound generators.
[0099] Turning now to FIG. 9 showing still another embodiment of
the invention, wherein a source (generator) of ultrasound energy is
disposed at the proximal end of the catheter. As illustrated in
FIG. 9, a distal end 102 of the catheter 100 is formed having a
convex-shaped region 104 with one pair of the symmetrically
arranged ultrasound energy generators 106 and 108. The
convex-shaped region 104 reflects the energy emitted from the
ultrasound generators. In this embodiment the beams 110 of the
ultrasound energy are optimally focused at a specific/predetermined
area within the body of the occlusion for a selective destruction
of its material/tissue. The focus of the beams 110 is disposed
along the longitudinal axis A-A of the catheter and spaced from the
distal end 102.
[0100] The convex-shaped region 104 may also form a suction cup
which facilitates engagement between the distal end 102 of the
catheter and the occlusion, so as to prevent spreading and
facilitates catching of the debris. In addition to the ultrasound
energy generators detector and/or sensors 112 can be provided at
the distal end of the catheter. The sensors/detectors detect data
related physical and chemical composition of the occlusion tissue
and transmit such data to the control unit. The computer or
microchip 35 of the control unit 30 receives and analyzes the
information obtained by the sensors/detectors 112 and is capable of
generating a control signal to adjust functionality of the
ultrasound energy generators, so as to optimize the destruction of
an occlusion in the blood vessel or other desired effect on
targeted soft tissue.
[0101] The convex-shaped region 104 of the catheter 100 provided
with the ultrasound energy generators is also adaptable for use
with the sleeve 50 slidably arranged at the exterior area 114. In
the expanded position illustrated in FIG. 10, the hollow interior
space 64 of the sleeve 60 serves as a housing for the convex-shaped
region 104 accommodating the ultrasound energy generators 106 and
108. In use the sleeve 60 is placed into the expanded into the
working position, and the distal end of the catheter with the
ultrasound energy generators is delivered through the interior
space 64 to the close proximity of the occlusion. In this manner,
the ultrasound beams 110 are optimally focused at a specific area
at the body of the occlusion for a selective destruction of its
material. The interior space 64 of the sleeve 60 forms a conduit
which accommodates materials cut during the procedure and improves
the flow of various fluids during aspiration and/or infusion. The
convex-shaped region 104 with the ultrasound energy generators are
precisely delivered to the occlusion and the walls of the sleeve
isolate the generators 106,108 from inner surfaces of the blood
vessel walls 112, minimizing the risk of accidental perforation of
the blood vessel walls.
[0102] Turning now to FIGS. 13 and 14 illustrating an embodiment of
the invention, wherein a source 190 (generator) of RF (radio
frequency) energy is disposed at the proximal end of the catheter.
As illustrated in FIG. 13 the catheter includes one or multiple
electric wires 192 longitudinally extending within a hollow
catheter body to deliver electric current/voltage to the RF
electrodes positioned at the distal end. In the alternate
embodiment the electrodes may be positioned at any place within the
body of the catheter between the proximal end and the distant end.
In use the RF energy destroys or affects a soft tissue or an organ
in a certain desirable way through cutting or coagulating
mechanisms or increase of temperature of targeted tissue. One of
the advantages of this embodiment is that only thin electric wires
are needed to transmit energy to RF electrodes at the distal end of
the catheter. Open spaces formed within the catheter body between
the wires and/or electrodes are used to evacuate ablated bodily
material produced during the procedure. The evacuation can be
accomplished, for example by a vacuum pump provided at the proximal
end of the system creating a low-pressure zone resulted in suction
pressure within the hollow inner space of the catheter, so that
ablated bodily material directly removed from the operating
site.
[0103] RF electrodes are positioned at the distal end, so that the
electric current alternating between electrodes destroys the
occlusion located between the electrodes efficiently covering the
surface of the occlusion. Because RF energy is delivered by means
of electric current alternating between electrodes spaced/separated
from inner areas of the blood vessel walls, application of RF
technology provides higher safety compare to other methods.
Therefore, possibility of damaging adjacent walls/tissues of blood
vessels is minimized.
[0104] In a manner previously discussed, detector and/or sensor 196
can be provided at the distal end of the catheter for determining
physical and chemical composition of the occlusion and by means of
the computer or microchip of the control unit to adjust
functionality of RF emitters.
[0105] The embodiment of FIGS. 9 and 10 was discussed with the
source (generator) of ultrasound energy being disposed at the
proximal end of the catheter. However, use of other energy
generators is also within the scope of the invention. For example,
the catheter can be provided with a cavitation source disposed at
the distal end to deliver cavitation waves to be used in the
intrabody surgery. In use the catheter passes through/positioned
within the blood vessels (veins or arteries), so that such waves
destroy or affect a soft tissue or an organ in a certain desirable
way through mechanically or chemical-mechanical properties and/or
forces. Outlets emitting cavitation energy can be added to the
distal end of an existing catheter.
[0106] According to one embodiment of the invention the cavitation
energy outlets are positioned on the outer diameter of the catheter
tip and disposed at the longitudinal axis passing through the
catheter. This facilitates focusing the cavitation waves at the
central area of the occlusion. In this arrangement while the
occlusions destroyed, the risk of damage to the blood vessel walls
is substantially reduced or minimized.
[0107] As previously discussed, detector and/or sensor are provided
at the distal end of the catheter capable determining physical and
chemical composition of the occlusion and by means of the computer
or microchip of the control unit to adjust performance of the
cavitation energy outlets.
[0108] Turning now to FIG. 16 showing that a stiffening mandrel or
wire 202 can be inserted through the bore or lumen of a hollow
guidewire 206 to cause a corresponding bend in the hollow guide
wire distal end. The stiffening mandrel or wire is utilized by the
invention to target the distal end of the catheter in required
direction within the vasculature as well as to target a desired
area on the tissue by properly navigating the ablative tip. FIG. 16
illustrates a specific application of this feature of the
invention, wherein 90-degree corner mandrel 202 is pushed through
hollow flexible guidewire to guide it through a 90 degree turn in
vasculature.
[0109] As illustrated on FIG. 17 a hollow guide wire 210 can also
include a string 212 attached to the exterior part of the distal
end 214. As further illustrated, the string 212 enters into the
internal hollow part of the guidewire through a hole 216 located at
predetermined optimal distance from the distal end. In this
embodiment by pulling the string 212 an operator can remotely
manipulate and/or bend the distal area of the guide wire 210 to an
optimum angle thus targeting the distal end into required direction
within the patient body lumens.
[0110] As illustrated on FIG. 18 a distal end of a guidewire can
include a bend or curved portion which facilitates navigation of
the guidewire in vasculature. Although various angles of
inclination of the distal end to the remaining part of the guide
wire are contemplated, in the preferred embodiment the distal end
is inclined at 30-degree angle.
* * * * *