U.S. patent application number 11/698807 was filed with the patent office on 2007-09-20 for device and system for surgical dissection and/or guidance of other medical devices into body.
Invention is credited to Brett S. Bowman, Thomas Daigle, Darrin Dickerson, David Francischelli, Douglas Gubbin, Christopher F. Kelly, David Kim, William W. Malecki, Christopher Plott, Adam Podbelski, Paul Rothstein, Mark Stewart, Mark Thompson, Benjamin K. Yaffe.
Application Number | 20070219550 11/698807 |
Document ID | / |
Family ID | 38015342 |
Filed Date | 2007-09-20 |
United States Patent
Application |
20070219550 |
Kind Code |
A1 |
Thompson; Mark ; et
al. |
September 20, 2007 |
Device and system for surgical dissection and/or guidance of other
medical devices into body
Abstract
A device for dissecting tissue and/or guidance of a second
device to a desired physiological location, the device comprising:
an elongate shaft comprising a proximal portion and a distal
portion, wherein the distal portion comprises a plurality of
segments that articulate with respect to one another; and a handle
attached to the proximal portion of the shaft, wherein the handle
comprises controls for articulating the plurality of segments of
the distal portion of the shaft with respect to one another. A
system for dissecting tissue and/or guiding a medical device to a
desired physiological location.
Inventors: |
Thompson; Mark; (Shakopee,
MN) ; Dickerson; Darrin; (Blaine, MN) ;
Bowman; Brett S.; (San Francisco, CA) ; Kelly;
Christopher F.; (Larkspur, CA) ; Malecki; William
W.; (Oakland, CA) ; Francischelli; David;
(Anoka, MN) ; Stewart; Mark; (Lino Lakes, MN)
; Daigle; Thomas; (Corcoran, MN) ; Gubbin;
Douglas; (Brooklyn Park, MN) ; Kim; David;
(Maple Grove, MN) ; Rothstein; Paul; (Elk River,
MN) ; Podbelski; Adam; (St. Paul, MN) ; Plott;
Christopher; (St. Paul, MN) ; Yaffe; Benjamin K.;
(San Francisco, CA) |
Correspondence
Address: |
KAGAN BINDER, PLLC
SUITE 200, MAPLE ISLAND BUILDING
221 MAIN STREET NORTH
STILLWATER
MN
55082
US
|
Family ID: |
38015342 |
Appl. No.: |
11/698807 |
Filed: |
January 26, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60762683 |
Jan 27, 2006 |
|
|
|
60852145 |
Oct 17, 2006 |
|
|
|
Current U.S.
Class: |
606/41 |
Current CPC
Class: |
A61B 18/1482 20130101;
A61B 90/30 20160201; A61B 2017/320044 20130101; A61B 2090/0811
20160201; A61B 2017/00367 20130101; A61B 2017/003 20130101; A61B
1/0055 20130101; A61B 17/00234 20130101; A61B 17/0218 20130101 |
Class at
Publication: |
606/041 |
International
Class: |
A61B 18/18 20060101
A61B018/18 |
Claims
1. A device for dissecting tissue and/or guidance of a second
device to a desired physiological location, the device comprising:
an elongate shaft comprising a proximal portion and a distal
portion, wherein the distal portion comprises a plurality of
segments that articulate with respect to one another; and a handle
attached to the proximal portion of the shaft, wherein the handle
comprises controls for articulating the plurality of segments of
the distal portion of the shaft with respect to one another.
2. The device of claim 1, wherein the plurality of segments
includes a distal segment, and the distal segment includes an
illumination source.
3. The device of claim 2, further comprising a switch for turning
the illumination source off and on.
4. The device of claim 3, further comprising a means for indicating
whether the illumination source is turned off or on.
5. The device of claim 4, wherein the means for indicating is a
light or illumination source located on the handle.
6. The device of claim 1, further comprising an articulation
indicator to indicate the amount of articulation of the distal
portion.
7. The device of claim 6, wherein the articulation indicator is
located on the handle.
8. The device of claim 1, further comprising a guide wire tube
having a proximal and a distal end, wherein the guide wire tube is
disposed along at least a portion of the length of the device and
the guide wire tube has openings at both the proximal and distal
ends.
9. The device of claim 8, further comprising a guide wire lock
connected to the proximal end of the guide wire tube, wherein the
guide wire lock in one position can allow a guide wire to pass
through the guide wire tube at the proximal end and in a second
position can hold the guide wire in place in the guide wire
tube.
10. The device of claim 1, wherein when the plurality of segments
articulate the articulation starts at a distal segment and moves
proximally through the plurality of segments.
11. The device of claim 1, wherein at least some of the plurality
of segments have piston lumens disposed length-wise within the
segments, the plurality of segments includes a distal segment, and
the controls for articulating the plurality of segments comprise: a
control wheel; a rack; a pinion, wherein the pinion is connected to
the control wheel and rotatably supported in the rack; a push/pull
rod having distal and proximal ends, wherein the proximal end is
connected to the rack; and a plurality of pistons, wherein one of
the plurality of pistons is disposed in each piston lumen of each
segment, the pistons are articuably connected to each other, a
distal piston is connected to the distal segment, and a proximal
piston is articuably attached to the distal end of the push/pull
rod, wherein rotation of the control wheel rotates the pinion,
which causes the rack and attached push/pull rod to be pulled or
pushed and further causes the pistons and corresponding segments in
which the pistons are disposed to articulate with respect to one
another.
12. The device of claim 11, further comprising a locking mechanism
that can retain the control wheel in a position.
13. The device of claim 12, wherein the locking mechanism comprises
a friction lock.
14. The device of claim 12, wherein the locking mechanism both
locks and unlocks.
15. The device of claim 11, wherein when the plurality of segments
articulates, the articulation begins at the distal segment and
moves proximally through the plurality of segments.
16. The device of claim 11, further comprising an articulation
indicator to indicate the amount of articulation of the distal
portion.
17. The device of claim 16, wherein the articulation indicator is
located on the handle.
18. A system for dissecting tissue and/or guiding a medical device
to a desired physiological location, the system comprising: a
dissecting/guiding device, comprising: an elongate shaft comprising
a proximal portion and a distal portion, wherein the distal portion
comprises a plurality of segments that articulate with respect to
one another; a handle attached to the proximal portion of the
shaft, wherein the handle comprises controls for articulating the
plurality of segments of the distal portion of the shaft with
respect to one another; and a guide wire tube through at least a
portion of the length of the dissecting/guiding device, wherein the
guide wire tube comprises proximal and distal ends each having an
opening; a guide wire that may be fed into the proximal end of the
guide wire tube, through the guide wire tube and out through the
distal opening of the guide wire tube; and a guide member
comprising an elongate structure with two ends, wherein a first end
may attach to a distal end of the guide wire and a second end that
may attach to a medical device, such that when the guide wire, with
a medical device attached, is retracted back through the guide wire
tube, a medical device is guided to a desired physiological
location.
19. The system of claim 18, further comprising a medical
device.
20. The system of claim 19, wherein the medical device is an
ablation device.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of both U.S. Provisional
Application having Ser. No. 60/762,683, filed Jan. 27, 2006,
entitled "MEDICAL DEVICE," and U.S. Provisional Application having
Ser. No. 60/852,145, filed Oct. 17, 2006, entitled "MEDICAL
DEVICE," which applications are incorporated herein by reference in
their entireties.
[0002] This application also incorporates by reference in its
entirety co-pending U.S. patent application having Ser. No. ______,
filed on the same day as the present application, entitled "METHOD
OF SURGICAL DISSECTION AND/OR GUIDANCE OF OTHER MEDICAL DEVICES
INTO BODY" and having Attorney Docket No. MTI0052/US
(P-22921.03).
FIELD OF THE INVENTION
[0003] The present invention relates generally to a medical device
and method for surgical dissection and/or guidance of other medical
devices into a body and, in particular, a medical device and method
for both dissecting cardiac tissue prior to positioning an ablation
device, and guiding the ablation device into a beating heart to
perform lesions on the heart during a minimally invasive
procedure.
BACKGROUND OF THE INVENTION
[0004] Various specialized medical devices, such as ablation
devices, cardiac leads, ultrasonic catheters, balloon angioplasty
catheters, electrophysiological diagnostic catheters, pressure
monitoring catheters, etc., may require the use of a delivery
system for deploying the device in a desired internal body space,
such as the heart, for example. In addition, in some cases,
dissection of tissue is desired or necessary to guide or deliver
such specialized medical devices to a desired location.
[0005] Although the present invention contemplates devices and
systems for dissecting tissue and/or guiding other specialized
medical devices to many areas of the body, in particular, the
present application will focus on one exemplary desired location
and one exemplary specialized medical device. The focus will be
primarily on delivery of an ablation device to an area on or near
the heart, which, in particular, is around the two separate pairs
of pulmonary veins on both sides of the heart. Similarly, the
present invention contemplates the use of the present inventive
devices and systems to treat various conditions. However, in
particular, the present application will focus on treatment for
heart arrhythmias (e.g., atrial fibrillation) using ablation
procedures.
[0006] In a normal heart, contraction and relaxation of the heart
muscle (myocardium) takes place in an organized fashion as
electrochemical signals pass sequentially through the myocardium
from the sinoatrial (SA) node located in the right atrium to the
atrialventricular (AV) node and then along a well-defined route
which includes the His-Purkinje system into the left and right
ventricles. Sometimes abnormal rhythms occur in the atrium which
are referred to as atrial arrhythmia. Three of the most common
arrhythmias are ectopic atrial tachycardia, atrial fibrillation,
and atrial flutter. Arrhythmia can result in significant patient
discomfort and even death because of a number of associated
problems, including the following: (1) an irregular heart rate,
which causes a patient discomfort and anxiety; (2) loss of
synchronous atrioventricular contractions, which compromises
cardiac hemodynamics resulting in varying levels of congestive
heart failure; and (3) stasis of blood flow, which increases
vulnerability to thromboembolism. It is sometimes difficult to
isolate a specific pathological cause of the arrhythmia, although
it is believed that the principal mechanism is one or a multitude
of stray circuits within the left and/or right atrium. These
circuits or stray electrical signals are believed to interfere with
the normal electrochemical signals passing from the SA node to the
AV node and into the ventricles.
[0007] Treatment of arrhythmias may be accomplished by a variety of
approaches, including drugs, surgery, implantable
pacemakers/defibrillators, and catheter ablation. While arrhythmic
drugs may be the treatment of choice for many patients, these drugs
may only mask the symptoms and do not cure the underlying cause.
Implantable devices, on the other hand, usually can correct an
arrhythmia only after it occurs. Surgical and catheter-based
treatments, by contrast, may actually cure the problem usually by
ablating the abnormal arrhythmogenic tissue or abnormal pathway
responsible for the arrhythmia. The catheter-based treatments rely
on the application of various destructive energy sources to the
target tissue including direct current energy sources to the target
tissue, including direct current electrical energy, radiofrequency
electrical energy, microwave energy, laser energy, cryoenergy,
ultrasound, and the like.
[0008] One surgical method of treating arrhythmia is the "Maze"
procedure, which relies on a prescribed pattern of incisions to
anatomically create a convoluted path, or maze, for electrical
propagation within the left and right atria. The procedure employs
incisions in the right and left atria, which divide the atria into
electrically isolated portions, and which in turn results in an
orderly passage of a depolarization wave front from the SA node to
the AV node, while preventing reentrant wave front propagation. The
Maze procedure has been effective in curing arrhythmias, but the
procedure is technically difficult. The procedure also requires
open heart surgery, in which the breastbone is divided and the
surgeon has direct access to the heart.
[0009] More recently, Maze-like procedures have been developed
utilizing ablation catheters that can form lesions on the
endocardium to effectively create a maze for electrical conduction
in a predetermined path. Typically, the lesions are formed by
ablating tissue with an electrode carried by a catheter. Ablative
energy, e.g., high intensity focused ultrasound (HIFU) energy,
radiofrequency (RF) energy, microwave energy and/or laser energy,
applied to the electrode, causes significant physiological effects
in the tissue resulting from thermal and/or mechanical changes or
effects. By controlling the energy level, the amount of heat
generated in the tissue and the degree of tissue damage or change
can also be controlled. Ablation uses lower levels of voltage that
creates sufficient heat to cause a desired cell damage, but leaves
the tissue structure intact so as to effectively block electrical
pathways within the tissue. Irrigation of the electrode(s) with
saline or other conductive fluid can decrease the interface
impedance, cool the tissue, and allow for a greater lesion
depth.
[0010] A treatment for atrial fibrillation, in particular, includes
ablation around the pulmonary veins, which procedure is called
pulmonary vein antrum isolation. Almost all the atrial fibrillation
signals are believed to come from the four pulmonary veins and move
to the atria. Ablation of the area of the atria that connects to
the pulmonary veins provides circular scar tissue that blocks
impulses firing within the pulmonary veins from moving to the
atria, thereby disconnecting the pathway of abnormal rhythm and
preventing atrial fibrillation.
[0011] Most ablation devices are designed to access the heart via a
mid-line sternotomy. More recently, ablation of cardiac tissue can
be carried out through a minimally invasive route, such as between
the ribs, through a sub-xyphoid incision or via catheter that is
introduced through a vein, and into the heart. Such minimally
invasive procedures are generally performed off-pump, which means
the heart is beating during the procedure. Such procedures
accordingly require several ports for medical devices to enter the
area of the heart and perform the procedures.
[0012] Ablation of a precise location within the heart requires
precise placement of an ablation device within or near the heart.
Precise positioning of the ablation device is especially difficult
because of the physiology of the heart, particularly as such
recently developed procedures generally occur off-pump. As
discussed earlier, in some cases, dissection of tissue is necessary
to guide or deliver specialized medical devices to their desired
location in the body. In particular, with regard to pulmonary vein
antrum isolation, tissue connecting each pair of pulmonary veins to
pericardial reflections is often dissected allowing ablation device
placement on and/or around the pulmonary veins.
[0013] In general, if prior art devices for dissection are used,
and if guidance of a specialized medical device to a location after
the dissection is desired, separate devices are used for dissection
and for placing the specialized medical device. Prior art devices
that allow for both dissection and placement of another device, in
particular with regard to ablation devices, require suturing a
catheter at or near the end of the device while the end of the
device is near the heart. Suturing near a beating heart involves
risk of negative consequences.
[0014] Thus, there is a need for an improved device that can
dissect tissue and guide specialized medical devices to particular
locations in the body. In particular, an improved device and method
for dissecting cardiac tissue and placement of ablation devices
during minimally invasive procedures on a beating heart are
desired.
SUMMARY OF THE INVENTION
[0015] The present invention relates to dissection of soft tissue
during general, ear, nose and throat (ENT), thoracic, urological,
and gynecological surgical procedures. The present invention is of
particular applicability for use during minimally invasive surgical
procedures or endoscopic procedures, such as during procedures on a
beating heart involving ablation (e.g., pulmonary vein antrum
isolation). The device includes a shaft with an articulating end
that is adjusted by controls in a handle. The articulated end helps
to navigate soft tissue around anatomic structures. The
articulating end preferably comprises a plurality of moveable or
articulable segments that help to dissect tissue and move around
anatomic structures. Preferably, the articulated end is also
illuminated for identification of distal tip location.
[0016] The device may be part of a system used to dissect tissue
and/or guide a specialized medical device to a location in the
body. The device may be inserted into a location in the body, as
described above, via a given entry route, for dissection of tissue.
While the device is in the location in the body for dissection
purposes, the device may also be used with other components of a
system to place a second device in the body. In order to place the
second device, the system preferably includes a guide wire that may
be fed through a lumen in the device and that may be advanced
through the device and connected to one end of a guide member,
which has two ends, and that is separate from the device. The guide
wire may then be retracted back through the device, with the guide
member attached, in order to pull the first end of the guide member
to a location in the body, and preferably adjacent or near the
distal tip of the device. The second end of the guide member may be
attached to a second device, such as a specialized medical device
(e.g., an ablation device). The device, with guide member attached,
may then be removed from the body by withdrawing the device back
through the port of entry, thereby pulling the guide member through
the same port, and furthermore pulling the second device on the
second end of the guide member into the location in the body at or
near where the dissection took place.
[0017] The present invention provides advantages over prior art
devices and methods for dissection of tissue and/or guidance of
medical devices into a body. One advantage is that a plurality of
articulable segments of a distal end of the device can have
different configurations allowing the end of the device to have,
for example, a straight configuration for insertion and removal
through a port during a minimally invasive surgical procedure and
also allowing the end of the device to articulate into controlled
curves while inside the body for dissection and placement purposes.
Another advantage is that a portion of the device can remain
outside of the body so as to indicate both a plane of articulation
and an amount of articulation of the articulating end of the device
for informing the user of such relevant information. Yet another
advantage of the present invention is the presence of an on-off
switch for an illumination source on the distal end of the device,
which allows the user to control whether or not an illumination
source is turned on. Also, an illumination source indicator is
preferably located on the handle, which provides the advantage of
allowing the user to know whether or not the illumination source is
turned on. A still further advantage is that a guide wire may be
used, through a lumen in the device, such as in the case of an
ablation procedure in particular, to place a device, which avoids
suturing inside the body (e.g., near the beating heart in ablation
procedures). Also, with regard to ablation procedures in
particular, an additional advantage is that the variability of the
articulation of the articulating end of the device allows a surgeon
some flexibility in the type of surgical approach chosen for a
given procedure and patient. For example, in pulmonary antrum
isolation procedures, a surgeon may choose to use either a superior
or an inferior approach to the procedure using the device and/or
system of the present invention.
[0018] A first embodiment of the present invention is a device for
dissecting tissue and/or guidance of a second device to a desired
physiological location, the device comprising: an elongate shaft
comprising a proximal portion and a distal portion, wherein the
distal portion comprises a plurality of segments that articulate
with respect to one another; and a handle attached to the proximal
portion of the shaft, wherein the handle comprises controls for
articulating the plurality of segments of the distal portion of the
shaft with respect to one another. The plurality of segments may
include a distal segment that includes an illumination source. The
device may include a switch for turning the illumination source off
and on. The device may include a means for indicating whether the
illumination source is turned off or on. The means for indicating
may be a light or illumination source located on the handle. The
device may include an articulation indicator to indicate the amount
of articulation of the distal portion. The articulation indicator
may be located on the handle. The device may further comprise a
guide wire tube having a proximal and a distal end, wherein the
guide wire tube can be disposed along at least a portion of the
length of the device and the guide wire tube can have openings at
both the proximal and distal ends. The device may also further
comprise a guide wire lock connected to the proximal end of the
guide wire tube, wherein the guide wire lock in one position can
allow a guide wire to pass through the guide wire tube at the
proximal end and in a second position can hold the guide wire in
place in the guide wire tube. The plurality of segments may
articulate and the articulation may start at a distal segment and
move proximally through the plurality of segments. The plurality of
segments may have piston lumens disposed length-wise within the
segments, the plurality of segments including a distal segment, and
controls for articulating the plurality of segments comprising: a
control wheel; a rack; a pinion, wherein the pinion is connected to
the control wheel and rotatably supported in the rack; a push/pull
rod having distal and proximal ends, wherein the proximal end is
connected to the rack; and a plurality of pistons, wherein one of
the plurality of pistons is disposed in each piston lumen of each
segment, the pistons are articulably connected to each other, a
distal piston is connected to the distal segment, and a proximal
piston is articulably attached to the distal end of the push/pull
rod, wherein rotation of the control wheel rotates the pinion,
which causes the rack and attached push/pull rod to be pulled or
pushed and further causes the pistons and corresponding segments in
which the pistons are disposed to articulate with respect to one
another. The device may further comprise a locking mechanism that
can retain the control wheel in a position. The locking mechanism
may comprise a friction lock. The lock may both lock and unlock
(i.e., is reversible). When the plurality of segments articulates,
the articulation may begin at the distal segment and move
proximally through the plurality of segments. The device may
further comprise an articulation indicator to indicate the amount
of articulation of the distal portion. The articulation indicator
may be located on the handle.
[0019] A second embodiment of the present invention is a system for
dissecting tissue and/or guiding a medical device to a desired
physiological location, the system comprising: a dissecting/guiding
device, comprising: an elongate shaft comprising a proximal portion
and a distal portion, wherein the distal portion comprises a
plurality of segments that articulate with respect to one another;
a handle attached to the proximal portion of the shaft, wherein the
handle comprises controls for articulating the plurality of
segments of the distal portion of the shaft with respect to one
another; and a guide wire tube through at least a portion of the
length of the dissecting/guiding device, wherein the guide wire
tube comprises proximal and distal ends each having an opening; a
guide wire that may be fed into the proximal end of the guide wire
tube, through the guide wire tube and out through the distal
opening of the guide wire tube; and a guide member comprising an
elongate structure with two ends, wherein a first end may attach to
a distal end of the guide wire and a second end that may attach to
a medical device, such that when the guide wire, with a medical
device attached, is retracted back through the guide wire tube, a
medical device is guided to a desired physiological location. The
system may further comprise a medical device. The medical device of
the system may be an ablation device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The present invention will be further explained with
reference to the appended Figures, wherein like structure is
referred to by like numerals throughout the several views, and
wherein:
[0021] FIG. 1 is a plan view of an exemplary surgical dissector and
guide, shown with an articulated distal portion of shaft, in
accordance with the present invention;
[0022] FIG. 2 is a plan view of an exemplary surgical dissector and
guide, shown laying on side and with a substantially straight
distal portion of shaft, in accordance with the present
invention;
[0023] FIG. 3 is a side view of an exemplary distal portion of a
shaft of a surgical dissector and guide, shown with a sheath, bands
and sheath coverings removed, in accordance with the present
invention;
[0024] FIG. 4 is a plan view of an exemplary distal portion of a
shaft of a surgical dissector and guide, shown without a sheath,
bands and sheath coverings, in accordance with the present
invention;
[0025] FIG. 5 is an exploded view of the exemplary distal portion
of FIG. 4;
[0026] FIG. 6 is an exploded view of components of an exemplary
surgical dissector and guide, in accordance with the present
invention, that comprise or may be attached to shaft of the
exemplary dissector and guide;
[0027] FIG. 7 is a plan view of an exemplary distal segment, in
accordance with the present invention, shown with guide wire tube
and electrical wires attached;
[0028] FIG. 8 is an exploded view of the exemplary distal segment
of FIG. 7;
[0029] FIG. 9 is a side view of the exemplary distal segment of
FIG. 7;
[0030] FIG. 10 is a cross-sectional view of the distal segment of
FIG. 9 taken along the line 10-10 of FIG. 9;
[0031] FIG. 11 is a cross-sectional view of a distal portion of a
shaft (and some of proximal portion), in accordance with the
present invention, showing the piston assembly;
[0032] FIG. 12 is an exploded view of an exemplary piston assembly,
in accordance with the present invention;
[0033] FIG. 13 is a plan view, from a distal end, of part of a
distal portion of a surgical dissector and guide, in accordance
with the present invention, showing a view from the distal end of a
cross section through a middle segment (segment 22, in
particular);
[0034] FIG. 14 is a plan view of a handle portion of the exemplary
dissector and guide shown in FIG. 2, in accordance with the present
invention, with a top half of a handle housing shown
disassembled;
[0035] FIG. 15 is a plan view of the handle portion of the
exemplary dissector and guide as shown in FIG. 14 with the top half
of the handle housing removed and a top half of a control wheel and
a shaft retainer both shown disassembled;
[0036] FIG. 16 is a top view of the handle portion of the exemplary
dissector and guide as shown in FIG. 15 with the top half of the
control wheel, the shaft retainer, and a portion of a guide wire
tube removed;
[0037] FIG. 17 is a plan view of the handle portion of the
exemplary dissector or guide as shown in FIG. 15 with the top half
of the control wheel and the shaft retainer removed and a shaft,
the guide wire tube, a rack, a jam bar, a jam plate and a spring
shown disassembled;
[0038] FIG. 18 is a plan view of the handle portion of the
exemplary dissector or guide as shown in FIG. 17 with the shaft,
the guide wire tube, the rack, the jam bar and the spring removed
and a portion of a control wheel lock assembly shown
disassembled;
[0039] FIG. 19 is a top view of a cam plate (a component of the
portion of the control wheel lock assembly shown in FIG. 18);
[0040] FIG. 20 is a plan view of the handle portion of the
exemplary dissector and guide as shown in FIG. 18 with the portion
of the control wheel lock assembly removed and a pinion, pins, a
bottom half of the control wheel, and a guide wire lock shown
disassembled;
[0041] FIG. 21 is a plan view of the handle portion of the
exemplary dissector and guide as shown in FIG. 20 with the pinion,
the pins, the bottom half of the control wheel and the guide wire
lock removed and a power source, power source wires, a power source
connector, a PCB, an illumination source on-off switch, an
illumination source indicator light, a shaft retainer pin, and a
power source stabilizer shown disassembled;
[0042] FIG. 22 is a top view of a proximal portion of a handle of
an exemplary dissector and guide, in accordance with the present
invention, shown with a top half of a handle housing removed;
[0043] FIG. 23 is an exploded view of an exemplary guide wire lock,
in accordance with the present invention;
[0044] FIG. 24 is a plan view of an exemplary guide member, in
accordance with the present invention;
[0045] FIG. 25 is a plan view of a torquer end of the exemplary
guide member shown in FIG. 24;
[0046] FIG. 26 is a plan view of the torquer end of the exemplary
guide member shown in FIG. 24, shown with a tube portion of the
guide member removed from the torquer;
[0047] FIG. 27 is an exploded view of the torquer end of FIG.
26;
[0048] FIG. 28 is a plan view of an exemplary dissector and guide,
in accordance with the present invention, with arrows showing
rotation of a control wheel toward a proximal end of a handle and
resultant articulation or curving of a distal portion;
[0049] FIG. 29 is a plan view of the exemplary dissector and guide
of FIG. 28, with arrows showing rotation of the control wheel
toward a distal end of the handle with resultant straightening of
the distal portion;
[0050] FIG. 30 is an illustration of a chest cavity of a patient
from the right side shown with a thoracotomy and two ports to
access the heart shown inside, and showing a distal portion of a
shaft of an exemplary dissector and guide, in accordance with the
present invention, entering one of the ports;
[0051] FIG. 31 is an illustration as in FIG. 30, with a close-up
view of the ports, heart, throracotomy etc. and showing the distal
portion of the shaft of the exemplary dissector and guide inserted
and articulated around a pair of pulmonary veins on the right side
of the heart, and, as indicated by the arrow, an articulation
locking mechanism switch moved to prevent the distal portion from
straightening;
[0052] FIG. 32 is an illustration as in FIG. 31, and showing a
guide wire being fed through a guide wire tube in the exemplary
dissector and guide and exiting the distal end of the dissector and
guide;
[0053] FIG. 33 is an illustration as in FIG. 32, and showing the
end of the guide wire that exited the distal end of the dissector
and guide attached to a guide member that may be pulled into chest
cavity through the thoracotomy by withdrawing the guide wire
through the guide wire tube (in direction as indicated by
arrow);
[0054] FIG. 34 is an illustration as in FIG. 33, and showing the
guide member in contact with the distal tip of the dissector and
guide, and also showing locking the guide wire in a guide wire lock
(by turning lock as indicated by arrow);
[0055] FIG. 35 is an illustration as in FIG. 34, and showing an
ablation device attached to the guide member, which may be moved
into the chest cavity through the thoracotomy, after the
articulation locking mechanism switch (i.e., control wheel lock
switch or lock switch) is moved to allow distal portion to
straighten as dissector and guide is withdrawn from the port, as a
result the ablation device may be pulled into position around the
pair of pulmonary veins;
[0056] FIG. 36 is an illustration as in FIG. 35, and showing the
ablation device in place around the pair of pulmonary veins (with
the guide member still attached to the ablation device);
[0057] FIG. 37 is a cross-sectional side view of a distal portion
of a shaft of an exemplary embodiment of a dissector/guide in
accordance with the present invention, showing a distal segment
articulated;
[0058] FIG. 38 is an illustration as in FIG. 37, showing a
subsequent step in a progression of articulation from the distal
segment proximally through multiple segments; and
[0059] FIG. 39 is an illustration as in FIG. 38, showing a
subsequent step in a progression of articulation from the distal
segment proximally through multiple segments;
[0060] FIG. 40 is an illustration as in FIG. 38, showing a
subsequent step in a progression of articulation from the distal
segment proximally through multiple segments.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0061] In the following detailed description of the preferred
embodiments, reference is made to the accompanying drawings which
form a part hereof, and in which is shown by way of illustration
specific embodiments in which the invention may be practiced. It is
to be understood that other embodiments may be utilized and
structural or logical changes may be made without departing from
the scope of the present invention. The following detailed
description, therefore, is not to be taken in a limiting sense, and
the scope of the present invention is defined by the appended
claims.
[0062] With reference to the accompanying figures, wherein like
components are labeled with like numerals throughout the several
figures, devices and systems for surgical dissection and guidance
of other medical devices, and methods of use thereof, are
disclosed, taught and suggested by the multiple embodiments. It is
understood that any of the devices and systems described may be
used for surgical dissection of and/or guidance of other
specialized medical devices to any part of a subject's body
including the human body or that of other animals or creatures. In
particular, it is contemplated that the devices or systems
described are useful during general, ENT, thoracic, urological, and
gynecological surgical procedures, although the applicable
procedures are not limited to those provided. The devices or
systems are useful during minimally invasive surgical procedures,
however they may also be useful in open surgical procedures.
[0063] The present invention is described below as developed for
the application of providing surgical dissection of tissue and
guidance of ablation devices, such as for example, in the treatment
of arrhythmias of the heart, as described above in the Background
section. However, the present invention is not limited to treatment
of arrhythmias of the heart. A device contemplated by the present
invention preferably includes basic functionality for dissecting
tissue in a location in a body and/or guiding another medical
device to a location in a body. Such a device preferably includes a
manner of changing the shape of a distal portion of the device in
order to dissect tissue. Such a device also preferably includes a
manner of changing the shape of a distal portion (e.g., curved
shape) for positioning the distal portion of the device in a
desired anatomical location (e.g., around a blood vessel) in a
body. In addition, such a device preferably includes a manner of
straightening a distal portion of the device in order to fit though
a surgical port. Further, such a device may provide a manner of
locking a distal portion in a certain shape or curvature and/or may
prevent the distal portion from being straightened once the distal
portion has a desired shape. Preferably, shape of a distal portion
is controlled from a proximal portion of the device, which may be
located outside of the body (i.e., ex vivo) while the distal
portion is inside the body. Also preferably, the ex vivo controls
for changing the shape of the distal portion of the device may
provide an operator with information about the shape of the distal
portion while the distal portion is in vivo. Such a device also
preferably includes a manner of illuminating the distal portion for
purposes of identifying its location, which is relevant for
dissection of tissue and/or proper placement of another device.
Still further, such a device may be part of a system for guiding
another medical device to a location in a body.
[0064] With reference initially to FIG. 1, a preferred embodiment
of a surgical dissector and guide 10 (hereinafter referred to as
"dissector"), in accordance with the present invention, is
illustrated having, generally, an elongate shaft 12 and a handle
14. In the case of ablation device procedures, the shaft 12 may be
sized and shaped to preferably allow the shaft 12 to be inserted
into the thoracic cavity through a trocar port (e.g., 10 mm or 12
mm). However, the device may be differently sized to be inserted
through other orifices, such as a small thoracotomy incision, e.g.,
roughly 1 cm, and/or various other incisions. The shaft 12
comprises a distal portion 16 and a proximal portion 18. The distal
portion 16, as seen in FIG. 1, preferably comprises a plurality of
segments that are interconnected and articulable. In the FIG. 1
embodiment the distal portion 16 is illustrated as comprising four
segments, which include a distal segment 20, and three middle
segments 22, 24, 26. The third middle segment 26 is connected to a
distal end 28 of the proximal portion 18 of the shaft 12. The
distal segment 20 preferably includes a distal tip 30. The distal
tip 30 of the shaft 12 may be smooth and convex in shape so as not
to cause unintended tissue damage when the distal tip 30 is
manipulated through tissue. The distal tip 30 preferably also
includes an illumination source 32. A proximal end 34 of the
proximal portion 18 is preferably rigidly retained by or attached
to the handle 14 at the distal end 36 of the handle 14.
[0065] The purpose of the illumination source 32 (e.g., a light)
may be to allow visualization of the location and placement of the
distal portion 16 within a body. The illumination source 32 may
provide sufficient illumination to visualize tissue and confirm the
placement of the distal portion 16 of the shaft 12 of the dissector
10. Preferably, the illumination source 32 comprises an LED.
Depending on any particular application, other illumination or
light sources are also contemplated. The illumination source 32 may
provide directional, non-diffuse light, e.g., white in color, with
a divergent beam including angle of less than about 45 degrees. The
illumination source 32 may, according to a preferred embodiment,
provide a light intensity that allows desired illumination of
pericardial tissue, for example, with a measurable range of
preferably about 5 to 30 foot-candles. However, a larger range of
illumination is also contemplated by the present invention, which
may be from about 1 to 1,000 foot candles. Preferably, the
illumination source 32 will not generate sufficient heat to raise
the distal tip 30 and surrounding tissue to greater than about
41.degree. C. for use in heart tissue, in particular.
[0066] The handle 14 of the dissector 10 shown in FIG. 1 provides a
handheld housing for components that may control the functions of
the dissector 10, such as for articulation of the distal portion 16
and illumination of the illumination source 32. The handle 14 shown
in FIG. 1 comprises a housing 38, an illumination source on/off
switch 40 (the switch 40 may allow the illumination source 32 to be
turned on and off during a procedure), an illumination source
indicator light 42, a control wheel 44, a lock switch 46, and a
guide wire lock 48 on the proximal end 50 of the handle 14. The
handle 14 may be designed to be used by an operator in their right
or left hand.
[0067] As discussed above, generally, the dissector 10 comprises an
elongate shaft 12 attached to a handle 14, with the shaft 12
comprising distal 16 and proximal 18 portions. In particular, the
distal portion 16 of the shaft 12 will be discussed in more detail.
The distal portion 16 preferably changes shape in order to dissect
tissue and/or to be positioned in a desired anatomical location.
Also, the distal portion 16 preferably may also have a
substantially straight configuration in order for the distal
portion 16 to fit through a surgical port.
[0068] FIG. 1 illustrates the distal portion 16 with segments 20,
22, 24, 26 articulated with respect to one another, and with
respect to the proximal portion 18. The purposes of such
articulation or movement may include, but not be limited to, to
help steer the end of the dissector 10 around anatomical
structures, to help dissect tissue, and to help position the
illumination source 32 behind and around the anatomic structures of
a beating heart, for example, with the handle 14 ex vivo. Different
amounts of selective and controlled articulation or movement of the
distal portion 16 by a user are possible, thereby allowing the
distal portion 16 to accommodate patients that vary in size and
anatomic structures. Also, different embodiments of the distal
portion 16 of the shaft 12 are contemplated by the present
invention, including, for example, embodiments including more or
less numbers of segments, using segments of different lengths and
sizes together or as similar variations and different attachment
means between such segments providing any degree of
segment-to-segment or segment-to-portion 18 articulation, such that
the distal portion 16 is able to articulate from a substantially
straight configuration to arcuate shapes of various configurations
and degrees of curvature and vice versa. An arcuate shape or curve
may have constant radius or changing radius as controlled at least
in part by the connection between segments and proximal portion 18
as to be understood from the description of those components
below.
[0069] FIG. 2 illustrates another possible shape or configuration
of the distal portion 16, which is with the segments 20, 22, 24 and
26 (not shown, but covered with sheath) arranged as a substantially
straight configuration or shape. A purpose of such a substantially
straight shape is to allow the shaft 12 to be both easily inserted
into and easily withdrawn from a body through a port having a small
diameter, such as a 10 mm trocar port or a 12 mm trocar port, as
examples.
[0070] In order to help prevent the components of the distal
portion 16 of the shaft 12 from inadvertently catching on tissue or
compressing tissue while the device is inserted into or during use
within a body, the distal portion 16 (and possibly also a portion
of the proximal portion 18) of the dissector 10 may be preferably
covered with a sheath 52 comprising a flexible material, such as
silicone, for example (although other materials are also
contemplated). Any material that is flexible or has an elasticity
to permit the degree of articulation of the segments, and that is
suitable for a given application, is contemplated. FIGS. 2-4
illustrate embodiments that include such a sheath 52. In order to
hold the sheath 52 in place on the shaft 12, the ends of the sheath
52 are illustrated as preferably covered with bands 54 preferably
comprising a heat shrinkable material that is heat shrunk around
the ends of the sheath 52. A suitable band material comprises a
heat shrinkable polyester, although other materials are also
contemplated by the present invention as may be suitable for
different applications.
[0071] FIG. 3 shows the distal portion 16 of the shaft 12 with the
sheath 52 and bands 54 disassembled from the distal portion 16 of
the shaft 12. In addition, FIG. 3 includes three segment coverings
56 that preferably comprise a heat shrinkable material (e.g., like
that comprising the bands 54). The segment coverings 56 cover each
of the three middle segments 22, 24, and 26, and are located over
the segments 22, 24, 26 and under the sheath 52. The purpose of the
segment coverings 56 is to hold certain components of the distal
portion 16, which run through the three segments 22, 24, 26,
together (which will be discussed in more detail below).
[0072] FIG. 4 shows a distal portion 16 of an exemplary shaft 12,
in accordance with the present invention, shown with a sheath 52,
bands 54 or segment coverings 56 removed, as the segments 20, 22,
24, 26 may be provided. FIG. 5 shows the distal portion 16 of FIG.
4 in an exploded view.
[0073] In order to allow the segments of the distal portion 16 to
articulate with respect to one another and with respect to the
proximal portion 18 of shaft 12, articulating connection joints are
provided between the segments. In particular, tongue and groove
joints 58 are shown in FIG. 5 as pivotally connecting the segments
20, 22, 24, 26 and segment 26 to the distal end 28 of the proximal
portion 18 of the shaft 12. Although tongue and groove joints 58
are shown in FIG. 5, other articulating connection joints as known
or developed in the future may instead be used that allow for
movement and/or articulation of the segments with respect to one
another, and as such are also contemplated by the present
invention. For example, another possible articulating connection
joint that may be used in the present invention is a ball and
planar, socket-like joint that is kept under tension. Other such
suitable articulating connection joints are also contemplated.
[0074] The tongue and groove joints 58 comprise: tongue portions 60
on the distal ends of the respective segments 22, 24, 26 and the
distal end 28 of the proximal portion 18 of the shaft 12; and,
groove portions 62 on the proximal ends of the segments 20, 22, 24,
26 provided by spaced elements 63. Holes 64 are preferably provided
through the tongue portions 60 and the elements 63 of groove
portions 62 which may be aligned to be coaxial such that pins 66
inserted through the holes 64 may pivotally attach or connect the
tongue 60 and groove 62 portions of the joints 58. Such joints 58
are preferably integrally made with segments but could be otherwise
provided. As shown, such tongue and groove joints 58 provide a
sufficient degree of rotation between adjacent components to permit
controlled shaping of the distal portion 16, in accordance with the
present invention. Such degree of rotation can be otherwise limited
or enhanced to a greater degree by modifying design features of the
tongues and grooves or by substituting other contemplated
articulating connection joints.
[0075] The elongate shaft 12 of the dissector 10 comprises the
distal portion 16 as well as the proximal portion 18. More detail
of the articulating distal portion 16 and components that extend
through the proximal portion 18 to the handle 14 is given below. A
purpose of the proximal portion 18 is to provide a shaft through
which components may extend between the distal portion 16 and the
handle 14. Another purpose of the proximal portion 18 is to
lengthen the shaft 12 so that the articulating distal portion 16
may reach farther into a body with the handle being ex vivo.
[0076] FIG. 6 shows an exploded view of the shaft 12 and components
that extend through the shaft 12 and into or through the handle 14
(some components not shown in previous Figs.). Beginning at the
most distal segment 20, the embodiment in FIG. 6 shows a flexible
guide wire tube 68 that fits within an opening 72 in the end of the
distal tip 30 of the distal segment 20 (not shown in FIG. 6, but
can be seen in FIG. 10 as 72) and that extends through groove 91
(as seen in FIG. 5), defined cumulatively as running lengthwise
through the segments 22, 24, 26, and the proximal portion 18 of the
shaft 12, as assembled in series. Preferably, each of the segments
20, 22, 24, 26 (and any number of more or less segments) includes
(as seen in FIG. 4) a groove 91 along and open to the outside of
each segment 20, 22, 24, 26, creating an opening for access and
containing internally passing elements, such as the guide wire tube
68 and electrical wires 76 as described below. Distal segment 20
preferably has such a groove 93 that only partially extends along
its surface to facilitate tube 68 to the opening 72, as shown in
FIGS. 4 and 10. The middle segments 22, 24, 26 preferably have such
a groove 91 that extends over the respective lengths thereof with
proximal most middle segment receiving elements like tube 68 from
an internal passage (not shown) of such proximal portion 18, while
internal passage is preferably defined entirely through the shaft
portion 18 to facilitate passage of the guide wire tube 68
extending to the distal tip 30. Discussion relating to later
figures illustrating the handle 14 will describe how the guide wire
tube 68 extends through the handle 14.
[0077] Another groove 111, like groove 91 for the guide wire tube
68, is also preferably located open and to the outside of the
segments 22, 24, 26 of distal portion 16, and preferably contains
the electrical wires 76. A portion of the groove 111 can be seen in
FIG. 13, discussed below. The discussion above with regard to the
groove 91 for the guide wire tube 68 also preferably applies to the
groove 111 for the electrical wires 76.
[0078] The guide wire tube 68 preferably comprises a coiled wire
tube made of 304 stainless steel (SS). The purpose of the guide
wire tube 68 is to provide a lumen in which a guide wire may be
retained or passed through the dissector 10. The guide wire tube 68
preferably comprises a flexible material or has a design that
provides flexibility such that the guide wire tube 68 is able to
articulate or move with the segments of the distal portion 16 of
the shaft 12 without closing off the lumen inside the tube 68 or
restricting movement of a guide wire retained in the tube 68. Any
other materials or designs that may provide such a flexible tube
are also contemplated by the present invention.
[0079] In order to provide power to the illumination source 32 in
the distal tip 30, preferably two electrical wires 76 connect the
illumination source 32 in the distal tip 30 of the distal segment
20 to a power source, which is preferably located in the handle 14.
FIG. 6 shows that the electrical wires 78 extend from the distal
tip 30 (i.e., LED housing), through the grooves 111 in each
respective segment (and through a groove in the distal segment 20,
which is not seen in any figures), and through the proximal portion
18 of the shaft 12 to the handle 14. Discussion relating to later
figures illustrating the handle 14 will describe how the electrical
wires 76 are connected to a power source in the handle 14.
[0080] More detail of the distal segment 20 as comprising the
distal tip 30 and a recessed portion 80, and how other components
extend there from, can be seen in FIGS. 7-10. FIG. 7 shows the
distal segment 20 assembled with guide wire tube 68 and electrical
wires 76 connected. FIG. 8 is an exploded view of FIG. 7. FIG. 9 is
a side view of the distal segment of FIG. 7, and FIG. 10 is a cross
section of FIG. 9. Together, FIGS. 7-10 illustrate that the
illumination source 32 is preferably placed in a cavity 78 in the
distal tip 30 that is open at the tip for the illumination source
32 to pass through. A proximal side of the distal tip 30 fits over
and connects to the distal end of the recessed portion 80 of the
distal segment 20. The guide wire tube 68 is shown extending
through groove 93 of the recessed portion 80 and the distal tip 30.
The electrical wires 76 are shown preferably soldered to the lead
end 82 of the illumination source 32. A pin 84 holds illumination
source 32 in place by extending through coaxially aligned holes 86,
88 located on the recessed portion 80 of the distal segment 20 and
the distal tip 30, respectively, and by retaining the illumination
source 32 between the recessed portion 80 and distal tip 30.
[0081] In order to cause controlled articulation of the segments of
the distal portion 16 with respect to one another, a piston
assembly 98 (FIG. 6) is preferably disposed within the distal
portion 16 and connected proximally to a push/pull rod 92 that
extends through the proximal portion 18 and into the handle 14,
where controls (which will be discussed later) are present to push
or pull the rod 92 which straightens or articulates the pistons and
segments. Referring back to FIG. 6, the figure shows a set of three
pistons 90, that are part of the piston assembly 98, and that are
lined up end-to-end and pivotally connected. The pistons 90 are
also attached to a push/pull rod 92 at the proximal end 94 of the
set of pistons 90. The piston assembly 98 is also preferably
disposed within pistons lumens (one of which shown in FIG. 13 as
109) through the segments 22, 24, 26, as shown in FIG. 11. FIG. 11
shows that the pistons 90 are pivotally connected and extend
lengthwise through (one each) the three middle segments 22, 24, 26
of the distal portion 16 of the shaft 12. Each of the three pistons
90 is generally slidably disposed within a respective one of the
three middle segments 22, 24, 26. The distal end 96 of the piston
assembly 98 is preferably pivotally connected to the recessed
portion 80 of the distal segment 20, and the proximal end 94 is
pivotally connected to the push/pull rod 92.
[0082] In order to allow the pistons 90 of the piston assembly 98
to articulate with respect to one another and with respect to the
distal segment 20 and push/pull rod 92, articulating connection
joints are provided between the components. In particular, FIG. 12
illustrates joints comprising grooves 100 and links 104 connected
by pins 106. Articulating connection joints, other than those shown
in FIG. 12, that allow for movement and/or articulation of the
pistons 90 with respect to one another and the other components,
could be used and are also contemplated by the present invention.
FIG. 12 shows that on both the proximal and distal ends of the
pistons 90 there is a groove 100 with two coaxially aligned holes
102 on spaced elements 103. The pistons 90 are preferably connected
together, to the recessed portion 80 of the distal segment 20, and
to the push/pull rod 92, using links 104 including two holes 107,
which are connected to the pistons 90 (and other applicable
components) by inserting pins 106 through coaxially aligned holes
102, 107 through the elements 103 and links 104, respectively. The
articulating connection joints described provide a sufficient
degree of rotation between adjacent components to permit controlled
shaping of the distal portion 16, in accordance with the present
invention. Such degree of rotation can be otherwise limited or
enhanced to a greater degree by modifying the design features of
the described joints or by substituting other contemplated
articulating joints.
[0083] FIG. 13 illustrates a cross section of a middle segment, in
particular segment 22. As illustrated in the embodiment shown in
FIG. 13, one of the pistons 90 is disposed in a piston lumen 109 in
segment 22, with the piston lumen 109 preferably running in the
axial direction as shown and also radially offset as shown (with
the dissector in the orientation shown in FIG. 1). The arrangement
of the piston assembly 98 in the distal portion 16, with the
pistons assembly 98 being axially offset as shown in FIG. 13,
results in articulation of the segments of the distal portion 16.
When the push/pull rod 92 is pulled proximally, the pistons 90
begin to articulate (curve upward as shown in FIG. 1) beginning
with the most distal piston 90. So, preferably, the segments 20,
22, 24, 26 articulate beginning with the distal segment 20. As the
distal portion 16 is straightened (when push/pull rod 92 is pushed
distally), the segments 20, 22, 24, 26 straighten in the reverse
order, beginning with the most proximal segment that is
articulated.
[0084] FIGS. 37-40 illustrate an exemplary, preferred progression
of the articulation of the segment of the distal portion 16 of the
shaft 12. FIG. 37 shows the distal segment 20 first articulated
when the push/pull rod 92 is pulled proximally and a link 104 lines
up with the joint 58 between the distal segment 20 and middle
segment 22 and is able to articulate with the joint 58. Next, FIG.
38 shows that as the push/pull rod 92 is pulled proximally farther,
the middle segment 22 also articulates when the link 104 on its
proximal end lines up with the joint 58 between the middle segment
22 and segment 24. FIGS. 39 and 40 show subsequent steps as the
push/pull rod 92 is pulled proximally until all segments 20, 22,
24, 26 are articulated with respect to the proximal portion 18 of
the shaft 12.
[0085] The progression of articulation of the segments, as
described above, is preferred for the embodiment described herein.
However, other progressions are also contemplated by the present
invention. For example, the segments could articulate from the
proximal-most segment to the distal-most segment. This alternative
progression of articulation can be possible if the lengths of the
pistons 90 and links 104 are reconfigured to change the order in
which the segments articulate. Also, other progressions are also
possible with the segments articulating in any desired order by
reconfiguring the lengths of the pistons 90 and links 104.
[0086] The embodiments of the invention illustrated in the figures
show the segments articulating in the same general plane. However,
it is also contemplated by the present invention that one or more
of the segments may articulate out-of-plane. This could be possible
by rotating the orientation of the joint 58 between adjacent
segments. Such out-of-plane rotation of a segment(s) (e.g., the
distal segment 20) could be advantageous for certain anatomy.
[0087] So as to reduce friction between the segments 22, 24, 26 and
the pistons 90, a lubricious coating or a sheath is preferably
coated, attached or deposited onto the pistons 90 and/or inside
piston lumens 109. FIG. 12 shows three sheaths 108 that are
preferably placed over each of the three pistons 90. The three
sheaths 108 preferably comprise polytetrafluoroethylene (PTFE) heat
shrink tubing cut to length, although other suitable materials may
also be used. An alternative to the sheath 108, which is also
contemplated by the present invention, is a lubricious coating
coated or deposited onto the pistons 90 and/or inside of the piston
lumens in the segments 22, 24, 26. Some examples of such lubricious
coatings include, but are not limited to, Dicronite.TM., silicone,
Teflon.TM., and other suitable polymers. The purpose of such
coatings or sheaths is to reduce friction that occurs between
similar materials rubbing on each other.
[0088] In order for the distal portion 16 of the dissector 10 to
articulate as desired, the present invention is not limited to the
assemblies discussed above. For example, instead of a piston
assembly 98 disposed in the segments, a different assembly may be
used. In the other contemplated assembly, stainless steel spring
temper ribbon wire may be used. The ribbon wire may have varying
thickness along the ribbon allowing for control of bending of the
ribbon wire at certain locations along its length. For example,
thinner sections of ribbon wire would be disposed in joint areas
between segments of a distal portion 16. In addition, the ribbon
wire may be over-molded with a lubricious material where the ribbon
wire is disposed in the segments of the distal portion 16, so that
the ribbon wire would be able to move through the segments. The
described ribbon wire assembly could be pinned at both ends to the
respective segments. Other configurations that allow for such
movement of segments in the distal portion 16 are also contemplated
by the present invention.
[0089] FIG. 13 also illustrates an example of how the guide wire
tube 68 and the electrical wires 76 may extend through the segments
22, 24, 26. The guide wire tube 68 is shown extending through
groove 91, which is also preferably radially offset, and the
electrical wires 76 are shown extending through groove 111, which
is also preferably radially offset (at a different location
though).
[0090] The guide wire tube 68, electrical wires 76 and the
push/pull rod 92 extend proximally through the tubular shaft
housing 110 that comprises the proximal portion 18 of the shaft 12,
and into the handle 14. In particular, the electrical wires 76 and
push/pull rod 92 allow for the illumination source 32, and the
articulating pistons 90 and segments in the distal portion 16 of
the shaft 12 to be controlled proximally from the handle 14. The
tubular shaft housing 110 provides a lumen 113 through which the
other components may extend to the handle 14.
[0091] Referring back to FIG. 6, some components, that are located
in the handle 14, are shown attached to the proximal end of the
push/pull rod 92. The proximal end of the push/pull rod 92 is
rigidly attached to a rack 112. The purpose of the rack 112 is to
linearly move the push/pull rod 92 back and forth in the dissector
10, which in turn can articulate or straighten the piston assembly
98, and, ultimately, can articulate or straighten the segments 20,
22, 24, 26 of the distal portion 16 with respect to one another and
the proximal portion 18 of the shaft 12. The rack 112 is preferably
aligned such that the rack 112 moves back and forth along the
length of the dissector 10. The rack 112, is preferably a generally
oval-shaped component, as shown, with a set of teeth 114 on an
inner surface 116 of the rack 112. In order to move the rack back
and forth other components found in the handle 14 cooperate with
the rack 112. The other components will be discussed below with
regard to description involving figures illustrating the handle
14.
[0092] FIG. 6 also shows a link 118 and a jam bar 120. The link 118
is preferably a male threaded connector that screws into female
voids (not shown), one such void in each of the rack 112 and the
jam bar 120, and connects the rack 112 and jam bar 120 together.
The purpose of the jam bar 120, and how it cooperates with other
components, will also be discussed below.
[0093] Details regarding the handle 14 and any exemplary enclosed
or attached components will be discussed below. FIG. 14 illustrates
generally an exemplary handle 14 (also shows part of the proximal
portion 18 of shaft), in accordance with the present invention,
shown with the top half 38a of the handle housing 38 removed.
[0094] FIG. 15 is the same handle portion as shown in FIG. 14 with
the top half 38a of the handle housing 38 removed and a top half
44a of the control wheel 44 and a shaft retainer 122 both shown
disassembled. When assembled, the shaft retainer 122 is held in
place in the handle 14 by two screws 124, and functions to rigidly
attach the shaft 12 to the handle 14. The top half 44a of the
control wheel 44 fits with the bottom half 44b over a dowel pin
126, and both halves 44a, 44b are held in place by the two halves
38a, 38b of the handle housing 38. The control wheel 44 rotates,
which functions to move a pinion 126 with respect to the rack 112,
which controls back and forth motion of the push/pull rod 92 and
articulation and straightening of the distal portion 16 of the
shaft 12 (more details of the components relating to the control
wheel 44 will follow). In the particular embodiment shown in FIG.
15, washers (one shown as 128 and the other hidden in FIG. 15)
provide space between the halves 44a, 44b of the control wheel 44
and the handle housing 38 such that the control wheel 44 may be
allowed to rotate. However, other methods of allowing rotational
movement of the control wheel 44 are also contemplated by the
present invention.
[0095] FIG. 16 is a top view of the handle 14 portion as in FIG.
15. FIG. 16 shows how the teeth 114 on the rack 112 cooperate or
fit together with a set of teeth 130 on a pinion 132. The pinion
132 includes a notch 134 into which a pin 136, also connected to
both halves 44a, 44b of the control wheel 44, fits and holds the
pinion 132. The pin 136 and notch 134 provide a way for the pinion
132 to move together with the control wheel 44 when rotated.
Therefore, rotation of the control wheel 44 also rotates the pinion
132, which, through the cooperating sets of teeth 114, 130, moves
the rack 112 backward and/or forward along the length of the
dissector 10, which in turn pulls or pushes the push/pull rod 72
such that the attached pistons 90, and the corresponding segments
22, 24, 26, in which the pistons 90 are disposed, articulate or are
straightened with respect to one another.
[0096] In order to lock the distal portion 16 of the shaft 12 in a
desired curve and/or in a substantially straight configuration, a
locking mechanism is provided in the dissector 10 to selectively
hold the push/pull rod 72 axially in an axial position. Locking the
distal portion 16 in a desired configuration may be desired during
certain procedures and in certain anatomical regions of a body.
FIG. 16, together with FIGS. 17 and 18, illustrate an exemplary
locking mechanism (i.e., an actuation mechanism lock) that may be
used to hold the control wheel 44 in place and thereby hold the
rack 112, push/pull rod 72, and thus the distal portion 16 of the
shaft 12, in a desired configuration. In particular, the locking
mechanism in the embodiment shown in FIGS. 16-18 comprises a
friction lock. In general, it is desired that any locking mechanism
used would preferably lock the distal portion 16 of the dissector
10 in a desired configuration and also unlock.
[0097] FIGS. 16-18 together show a friction lock and its
components. The jam bar 120, which is attached to the rack 112, may
extend through an aperture 138 in a jam plate 140. The aperture 138
shown (FIG. 17) has a square shape, but other shapes are also
contemplated (e.g., circular). The purpose of the aperture 138 is
to allow the jam plate 140 to either contact the jam bar 120 or
not, which locks or unlocks, respectively, the friction lock. The
aperture 138 preferably has a diameter or other applicable
dimension(s) that are slightly larger than the outer diameter or
dimension of the jam bar 120 to allow the jam plate 140 (i.e.,
friction lock) to slide along the jam bar 120. A spring 142
surrounds the jam bar 120 on the proximal side of the jam plate
140. The purpose of the spring 142 is to maintain compression, as
the dissector 10 may be used in various orientations. The jam bar
120, jam plate 140 and spring 142 are disposed in a housing 144.
The jam bar 120 is shown extending through two channels 146 in the
housing 144. The jam plate 140 and spring 142 are also disposed
within the housing 144. The housing 144 is attached to the lower
half of the handling housing 38b by two screws 148.
[0098] FIG. 18 provides an exploded view of a portion of the
locking mechanism, as in FIG. 17, with the rack, 112, jam bar 120,
jam plate 140 and spring 142 removed. The portion of the locking
mechanism in FIG. 18 shows components that may function to move the
jam plate 140 so the jam plate 140 either contacts the jam bar 120
or allows the jam bar to move through the aperture 138 in the jam
plate 140, which locks or unlocks the friction lock, respectively.
FIG. 18 illustrates that the lock switch 46 attaches to a cam plate
150 using a screw 152. The cam plate 150 and lock switch 46
together can move back and forth in an opening 154 in the handle
housing 38b, which is oriented along the length of the dissector
10, in order to activate or inactivate the locking mechanism for
the control wheel 44. In the exemplary locking mechanism shown in
FIGS. 16-18, when the lock switch 46 is in a locked position, or
moved toward the proximal end 50 of the handle 14, a follower plate
156 with an attached follower pin 158 are moved toward the jam bar
120 so the follower pin 158 allows the jam plate 140 to tilt
against another pin 163 and frictionally engage the outer surface
of the jam bar 120. The follower plate 156 includes grooves 160
that mate with grooves 162 (as shown) on a rail plate 164 that is
attached to the bottom half 38b of the handle housing 38. As seen
in FIG. 19, which shows the cam plate 150, there is a slot 166 in
the cam plate 150 in which the follower pin 158 rides (the slot
being angled at about a 45 degree angle from the direction that the
cam plate 150 moves along the length of the dissector 10, with the
general direction being indicated by the double-ended arrow in the
figure). As the cam plate 150 is slid along the length of the
device, the described configuration results in the follower plate
156 and pin 158 moving generally perpendicular to the direction of
the lock switch 46 and cam plate 150 (which is along the length of
dissector 10). The result is that the follower pin 156 may be
pushed against the jam plate 140 in such a way to move the jam
plate 140 to either allow the jam bar 120 to pass through the
aperture 138 or not. When the lock switch 46 is in an unlocked
position, or moved toward the distal end 36 of the handle 14, the
follower pin 158 is moved away from the jam bar 120 through the
slot 166 in the cam plate 150, which moves the jam plate 140 such
that the jam bar 120 is able to move freely though the aperture 138
in the jam plate 140. A purpose of the configuration chosen for the
locking mechanism is to translate movement of the switch 46 that
goes along the length of the dissector 10 to movement that is
perpendicular to the movement of the switch 46.
[0099] In the exemplary embodiment of the locking mechanism
described above, once the dissector 10 is properly positioned, the
locking mechanism may be activated. In this preferred embodiment,
the control wheel 44 may still be rotated to further articulate the
segments of the distal portion 16, but the control wheel 44 cannot
be rotated in a direction to straighten the segments. Other
embodiments are, however, contemplated that would also include
preventing further articulation of the segments when a locking
mechanism is activated.
[0100] The exemplary locking mechanism described above is just one
example of a locking mechanism that may be used in the present
invention, and many other locking mechanisms are also contemplated
by the present invention (e.g., a ratchet system or a cam
mechanism).
[0101] FIG. 20 is the same embodiment of the handle 12 as in FIG.
19, except the locking mechanism components of FIG. 19 are removed,
and the pinion 132, dowel 126, lower half of the control wheel 44b,
a washer 168, a female luer 169, and the guide wire lock 48 are
shown disassembled. The figure illustrates a second washer 168 that
is placed on the dowel pin 126 between the lower half 38b of the
handle housing 38 and the lower half 44b of the control wheel 44
such that, along with the other washer 128 (in FIG. 15), the
control wheel 44 may be free to rotate inside the handle housing 38
on the pin 126. The purpose of the second washer 168, just like the
first washer 128, is to allow the control wheel 44 to rotate freely
with respect to the handle housing 38 (38b in particular with
respect to the second washer 168). FIG. 20 also illustrates that
the guide wire lock 48 is retained in the handle 14 by being
attached to the female luer 169 that is held between a guide wire
lock retainer 170 and the top half 38a (not shown) of the handle
housing 38.
[0102] FIG. 21 is an exemplary portion of the device shown in FIG.
20 with the components shown disassembled in FIG. 20 removed in
this figure, and with a printed circuit board (PCB) 172, the
illumination source on/off switch 40, the illumination source
indicator light 42, a shaft retainer pin 174, a power source 176, a
power source connector 178, power source wires 180, and a power
source stabilizer 182 shown disassembled from the bottom half 38b
of the handle housing 38. The purpose of the power source 176 is to
provide power for the PCB 172, and ultimately the illumination
source 32 and illumination source indicator light 42. The power
source 176 in the portion of the exemplary dissector 10 shown in
FIG. 21 is a 9-volt battery. Other power sources, however, are also
contemplated by the present invention. Preferably, the power source
176 is a disposable battery. The disposable battery may be a
disposable lithium battery. The power source 176 may be capable of
powering the illumination source 32 and the illumination source
indicator light 42 to a desired intensity for any determined time
period. The power source may be removable. The connector 178 and
the power source wires 180, in the preferred embodiment shown in
the figure, extend and attach to the PCB circuit 172. Electrical
wires (not shown in the figure) extend from the PCB circuit 172 to
the illumination source indicator light 42 and (wires 76) to the
illumination source 32 in the distal tip 30 of the shaft 12. In
order to stabilize the power source 176 in the handle housing 38
and prevent movement of the power source 176 in the handle 14, the
power source 176 may be attached to the power source stabilizer
182, as in FIG. 21. The power source stabilizer 182 may comprise,
for example, a foam spacer (as shown in figures), hot glue, a
spring, or any other suitable material or form for a given
application. FIG. 21 also includes the shaft retainer pin 174 that
prevents the tubular shaped shaft 12 from rotating.
[0103] FIG. 22 is a top view of a portion of the handle 14 near the
proximal end 50 shown with the top half 38a of the handle housing
38 removed. The figure illustrates that the guide wire tube 68, in
the exemplary embodiment, extends through the handle 14 such that
it extends by the power source 176 toward the top half 38a of the
handle housing 38. The figure also illustrates how the guide wire
tube 68 extends into the female luer 169. A guide wire may continue
out the opening 74 through a lumen 181 in the female luer 169 and
through a lumen 183 in the guide wire lock 48 to the proximal
opening 74.
[0104] Another feature of the present invention is that the
dissector 10 may include an indicator, preferably on the handle 14,
to indicate to the user to what extent the distal portion 16 is
curved or articulated. The purpose of such an indicator is to
inform the user of the amount of curvature of the distal portion
16, which may be important for a given procedure or with regard to
a particular anatomical position. For example, the control wheel 44
may have tactile features that indicate to the user to what extent
the distal portion 16 of the shaft 12 is deflected or articulated.
Additionally, or alternatively, the handle 12 may include a
graphical angle indicator or indicators that coordinate with the
rotation of the control wheel 44 to indicate the amount of
articulation of the distal portion 16, such as that shown as 230 in
FIG. 1. In the embodiment shown in FIG. 1, as the control wheel 44
is rotated, an indentation on the control wheel 44 may generally
line up with one of three graphical indicators 230, which
graphically illustrate the approximate amount of articulation of
the distal portion 16 of the shaft 12. Other types of indicators
are also contemplated by the present invention.
[0105] FIG. 23 is an exploded view of the exemplary guide wire lock
48. A purpose of the guide wire lock 48 may be to hold or lock (and
also release or unlock) a guide wire positioned through the guide
wire tube 68 of dissector 10 in a desired position or location. A
purpose for locking the guide wire in place is discussed below with
regard to a method embodiment of the present invention. The
exemplary guide wire lock 48, although other embodiments are also
contemplated, comprises a fitting 184, a washer 186, a collet 188,
an insert 190, and a knob 192. A lumen 183 extends through each of
the components of the guide wire lock 48, providing a space for a
guide wire to move through the guide wire lock 48. However, a
portion of the lumen 183 may also be closed if the guide wire lock
48 is in a locked configuration. A guide wire may be locked into a
position, for example, by turning the knob 192 clockwise, which
tightens the lock 48 around the guide wire. In particular, the
fitting 184 and knob 192 are cooperatively threaded (not shown)
such that when the knob 192 is turned clockwise, it moves closer to
the fitting 184, which in turn moves the collet 188 into the insert
190. The collet 188 has any number of slots such that when the
collet 188 is moved into the insert 190 the collet 188 is radially
compressed. The collet 188 is also preferably made of a lubricious
polymer (e.g., Delrin.TM., PEEK.TM., or certain grades of nylon),
such that the collet 188 is able to move as necessary within the
other components of the guide wire lock 48. Therefore, if a guide
wire extends through the lumen 183 that runs through the collet
188, the guide wire may be held in place by the compressed collet
188.
[0106] The dissector 10, as described above, may be used to dissect
tissue. Additionally, or alternatively, the dissector 10 may be
part of a system, including other components or devices, used to
guide another medical device into a desired location in a body.
Other components or devices that may be used with the dissector 10
comprise a guide wire (example is 218 in FIGS. 32-35), a guide
member 194, and another medical device (e.g., an ablation device
222 as in FIG. 35) that is to be placed in a location in a
body.
[0107] In general, the guide wire, as part of the system, may be
used to guide a medical device to a desired location in a body.
More detail of how the guide wire is used in the system in
accordance with the present invention is provided below. However,
in general, a distal end of the guide wire is fed through the guide
wire tube 68 in the dissector 10 from opening 74 and out through
opening 72, after the distal portion 16 of the dissector 10 is in a
desired location in a body. The distal end of the guide wire may
then be attached to the guide member 194 (having first and second
ends) at a first end and then withdrawn back through the guide wire
tube 68 until the guide member 194 comes near or into contact with
the distal tip 30 of the dissector 10. The guide wire is then
locked using the guide wire lock 48, and the dissector 10 and guide
wire, with guide member 194 attached are withdrawn back through an
port of entry. The dissector 10, guide wire and attached guide
member 194 may pull another medical device, which may be attached
to the second end of the guide member 194, into the location in the
body where the distal portion 16 of the dissector 10 was located
prior to withdrawal.
[0108] In the present invention, any type of known or future
developed guide wire may be used with the system. An exemplary
guide wire is a floppy, straight-tip, 0.035'' guide wire. The guide
wire may include markings to gauge the amount of guide wire being
extended through and out from the dissector 10, which can assist in
medical device placement procedures, for example.
[0109] FIG. 24 illustrates an exemplary guide member 194. The
purpose of the guide member 194 is to guide a medical device to a
desired location. As part of the system, in accordance with the
present invention, the guide member attaches, at one of two ends,
to a guide wire that is withdrawn back through the dissector 10
through which the guide wire is fed. The second end of the guide
member 194 is preferably attached to a medical device that is
desired to be placed in a body. Therefore, when the guide wire is
withdrawn, the guide member is pulled into the body adjacent the
distal tip 30 of the dissector 10. The guide wire is locked in
place in the dissector 10 and then the dissector and wire are
withdrawn, which pulls the guide member through, and ultimately
pulls a medical device that may be attached to the second end of
the guide member into a desired location in a body.
[0110] The exemplary guide member 194 comprises an elongate tube
196 with a torquer 198 on a first end 207 of the tube 196 (having
first 207 and second 208 ends). FIG. 25 illustrates the end of the
guide member 194 including the torquer 198. The torquer 198 has
configurations such that it may retain guide wire and may, with a
change in configuration, release the guide wire. FIG. 26 includes
the same portion of the guide member 194 as in FIG. 24 with the
torquer 198 removed from the tube 196. FIG. 27 is an exploded view
of the torquer 198, which comprises a torquer body 220, collet 202,
and torquer tip 204. The tapered end 206 of the torquer body 200
preferably fits inside the tube 196 in order to hold the torquer
198 in place in the tube 196. The guide wire member 194,
preferably, may be used to lock and release an end of a guide wire
in the torquer 198 or may otherwise be capable of attaching or
coupling to the distal portion 16 of the dissector 10. Moreover,
the guide wire member 194, preferably, may, on the other end of the
tube 208 (as seen in FIG. 24), reversibly hold a medical device
that is desired to be guided into or placed in a location in a
body.
[0111] The torquer 198 may retain a guide wire, or lock the guide
wire in place, by radially compressing the guide wire within a
lumen running through the torquer 198. the torquer tip 204 is
cooperatively threaded to the torquer body 200 (not shown), such
that when the torquer tip 204 is turned (e.g., clockwise) the
torquer tip 204 moves closer to the torquer body 200, which in turn
causes the collet 202 (which is attached to the torquer body 200)
to be pushed into the tip 204 and compressed in the tip 204 in an
accordingly shaped orifice (not shown) in the tip 204. The collet
202 has any number of slots that allow the collet 200 to be
radially compressed. The collet 202 is also preferably made of a
lubricious polymer (e.g., Delrin.TM., PEEK.TM., or certain grades
of nylon), such that the collet 202 is able to move as necessary
within the other components of the torquer 198. Therefore, a guide
wire running through a lumen in the torquer 198, and collet 202,
may be compressed and held in place.
[0112] Preferably, the torquer 198 and the end 208 of the guide
member 194 may both be sized and shaped to pass through a small
thoracotomy incision (e.g., roughly 1 cm, and/or a 10 or 12 mm
trocar port). The guide member 194 may have a length sufficient to
enter a superior thoracic incision, pass around one or more
anatomic structures of the heart and then exit an inferior thoracic
incision, whereby both ends of the guide may be visible ex vivo or
outside the patient's body (e.g., roughly 16'' to 18''). The guide
member 194 may have a smooth shape to allow its passage around
various anatomic structures while not causing substantial tissue
damage. The guide member 194 may have one or more portions that
have a durometer range of about 40 to 90 shore A.
[0113] FIG. 28 illustrates (with arrows) how, in an exemplary
embodiment of the present invention, rotating the control wheel 44
towards the proximal end 50 of the handle 14 curves or articulates
the distal portion 16 of the shaft 12 of the dissector 10 into a
curved configuration. As shown in FIG. 29, rotating control wheel
44 towards the distal end 36 of the handle 14 returns the dissector
100 to its original configuration, i.e., straightens out the distal
portion 16. Although not shown in FIGS. 28, 29, graphical
indicators on the handle 14 may be included that correlate to the
amount of curvature of the distal portion 16 based on the amount of
control wheel 44 rotation.
[0114] For use in cardiac procedures, such as those treating
arrhythmias of the heart as described above, the overall length of
the dissector 10 may preferably be roughly less than or equal to 70
cm. The useable shaft 12 length including an articulating distal
portion 16 at 0 degrees may be roughly less than or equal to 50 cm.
The shaft 12 is preferably of suitable length to allow a surgeon to
position the distal portion 16 of the dissector 10 behind and
around anatomic structures of a beating heart without unintended
tissue damage. The handle 14 length may be roughly less than or
equal to 30 cm. The handle 14 outer diameter, where the handle 14
is to be gripped by the operator, may be roughly be 2.5 to 5 cm.
The shaft 12 outer diameter may be roughly 0.250'' to 0.4375''. The
length of the distal portion 16 having the ability to be
articulated may be about 5 cm to 15 cm. The range of motion of the
articulating distal portion 16 may have a range of motion of about
0 to at least 180 degrees and, in one embodiment, not more than 180
degrees and, in another embodiment, between 0 and 165 degrees. The
variable radius of articulation of the distal portion 16 may have a
minimum radius of about 2.5 cm, when articulated at about 165
degrees, thereby allowing proper positioning around certain
anatomic structures, e.g., cardiac structures.
[0115] The present invention also includes a method of using the
dissector 10 and the other components of the system, and a method
of dissecting and/or guiding a medical device (e.g., ablation
device) into a body. One exemplary method using minimally invasive
techniques is described below with reference to FIGS. 30-36.
However, other methods, using different points of entry or an open
surgical approach, for example, are also contemplated by the
present invention.
[0116] FIG. 30 is an illustration of a chest cavity of a
representative patient with a view from the right side of the
patient. FIG. 30 includes a view of the heart 208, a thoracotomy
210 and first and second ports 212, 214, respectively. FIG. 30 also
illustrates a first step in a procedure or method of using the
dissector 10 of the present invention for an ablation procedure,
and pulmonary antrum isolation, in particular. As can be seen in
FIG. 30, the distal tip 30 of the shaft 12 is first inserted
through a first port 212, or pericardial incision, that provides
access to the heart. The first port 212 may be a roughly 1 cm
incision or a 10 mm trocar port, for examples, although other sizes
are also contemplated. The distal portion 16 of the dissector 10 is
in a substantially straight configuration so that the distal
portion 16 may pass easily through the port 212. The dissector 10
is then advanced into the body so that the distal tip 30 is near
the area of the pair of pulmonary veins 216 on the right side of
the heart and near the pericardial reflections (on the back side of
the heart, and not seen in Fig.) that generally need to be
dissected to place an ablation device properly in pulmonary antrum
isolation procedures. The illumination source 32 of the dissector
10 may be illuminated to help confirm the location of the distal
tip 30. The distal tip 30 may be used to create a passageway
through the pericardial reflections by perforating the pericardial
reflections with the tip 30.
[0117] FIG. 31 illustrates a next step in the method of using the
dissector 10 for pulmonary antrum isolation. Once the distal tip 30
is in the desired location near the pulmonary veins 216, as shown,
the control wheel 44 is rotated toward the proximal end 50 of the
handle 12, which articulates the distal portion 16 of the shaft 12
of the dissector 10 around the pulmonary veins 216. The
articulation lock 46 is then moved to a locked position (as
indicated by the arrow) so that the distal portion 16 may stay in
the desired articulated position around the pulmonary veins 216 and
will not straighten until desired.
[0118] FIG. 32 illustrates the next step in the method, which is to
place a guide wire 218 in the opening 74 (shown by arrow) and
extend the guide wire 218 through the guide wire tube 68 so that
the distal end 220 of the guide wire 218 extends out (e.g., by
approximately 1 cm) the distal end of the guide wire tube 68, or
opening 72, in the distal tip 30, as shown. The guide wire 218 is
then extended out through the thoracotomy 210 where it is to be
connected to a guide member 194 (not shown in Fig.). Although the
exemplary method involves extending the guide wire 218 out through
the thoracotomy 210, the guide wire 218 could alternatively extend
out of the body through a smaller opening or port. If so, it may be
necessary to use a surgical forceps to reach into the opening or
port and grab the distal end 220 of the guide wire 218 and pull it
out through the port, where it could be attached to a guide member
194.
[0119] Next, as illustrated in FIG. 33, the guide wire 218 is
connected to a guide member 194. The connection between the guide
wire 218 and the guide member 194 may be made by inserting the
guide wire 218 in the end of the torquer 198 on the guide member
194. The torquer tip 204 may then be twisted, e.g., clockwise, to
secure the guide wire 218 in place. The next step, as illustrated
in FIG. 33, is to pull the guide wire 218 back out through the
dissector 10 in the direction shown by the arrow, which moves the
guide member 194 closer to the end of distal tip 30 of the
dissector 10. The guide wire 218 is pulled until the torquer 198 of
the guide member 194 comes substantially into contact with the
distal tip 30 of the dissector 10, as shown by FIG. 34. The next
step, also illustrated in FIG. 34, is to lock the guide wire lock
48 by turning (as shown by arrow), e.g., clockwise, the guide wire
lock 48.
[0120] FIG. 35 illustrates a next step in the method, which is to
attach an ablation device 222 to the end of the guide member 194
opposite the torquer 198. In order to guide the ablation device 222
into the body to the correct location, the next step in the method
is to withdraw the dissector 10 (and guide wire 218) back out
through the port of entry 212 and thereby pull the ablation device
222 into place. In order to remove the dissector 10, the distal
portion 16 generally needs to be straightened first by unlocking
the articulation lock 46 (as shown by arrow) and then by rotating
the control wheel 44 toward the distal end 36 of the handle 14 the
dissector 10. The dissector 10 is then manually withdrawn from the
first port 212. As a result, the attached guide member 194 is
pulled through the pericardial reflections and out through the port
212, thereby pulling the attached ablation device 222 to the area
of pulmonary veins 216. In order to place the ablation device 222
around the pulmonary veins 216, as shown in FIG. 36, the jaws 224
of the ablation device 222 are closed around the veins 216.
[0121] Any known or future developed ablation device is
contemplated as being used with the present invention. Such an
ablation device may apply any type of suitable energy, such as RF
energy, HIFU energy, microwave energy, thermal energy, cryogenic
energy, laser energy or ultrasound energy, for examples, to target
tissue. A particular, preferred ablation device is a bipolar
ablation device, although all types of ablation devices are
contemplated.
[0122] In other embodiments of the present invention, it is
contemplated that the dissector 10 can include components for other
purposes besides dissection and guidance. For example, instead of
using the dissector 10 to place a separate ablation device, the
means for performing ablation (e.g., ablating or energy transfer
elements) may be included in the dissector 10. The means for
performing ablation or energy transfer can comprise any energy
transfer elements that transfer energy to target tissue. For
example, energy may be conductive elements that may supply RF
energy (as shown in Figs), HIFU energy, microwave energy, thermal
energy, cryogenic energy or ultrasound energy to target tissue.
Energy transfer elements may be, for example, laser elements for
supplying laser light to target tissue. Two or more energy transfer
elements or conductive elements may be arranged in a bipolar
arrangement wherein at least one element is used as a positive
electrode and at least one element is used as a negative electrode.
One or more energy transfer elements or conductive elements of the
ablation device 12 may be arranged in a monopolar arrangement
wherein at least one element is used as one electrode and an
indifferent electrode is placed elsewhere on the patient's body
such as the back, thigh or shoulder or another site other than the
ablation device 12 site.
[0123] Energy transfer elements or conductive elements may comprise
one or more conductive materials or blends including titanium,
titanium alloys, TiNi alloys, shape memory alloys, super elastic
alloys, aluminum oxide, platinum, platinum alloys, stainless
steels, stainless steel alloys, MP35N, elgiloy, haynes 25,
satellite, pyrolytic carbon, silver carbon, conductive metals,
conductive polymers or plastics, and/or conductive ceramics. Energy
transfer elements or conductive elements may not be conductive but
may serve as a conduit to deliver a conductive material such as a
conductive fluid. Energy transfer or conductive elements may be
porous. For example, energy transfer elements or conductive
elements may comprise porous polymers, metals, or ceramics. Energy
transfer elements or conductive elements may be coated with
non-stick coatings such as PTFE or other types of coatings as
discussed herein. In particular, the energy transfer elements may
comprise one or more coatings, e.g., hydrophilic coatings. Energy
transfer elements or conductive elements may be flexible thereby
allowing them to conform to the surface of target tissue. Energy
transfer elements or conductive elements may be malleable thereby
allowing a surgeon to shape them to conform to the surface of
target tissue.
[0124] Energy transfer elements or conductive elements may comprise
one or more metal conductors such as windings inside a polymer or a
conductive mesh material. The energy transfer elements or
conductive elements may comprise tubes for delivery of fluids. The
tubes may comprise holes or slots. A polymer tube may be placed
inside a metal tube to control fluid delivery through energy
transfer elements or conductive elements. One or more of the energy
transfer elements or conductive elements may be used as one or more
nerve stimulation electrodes and/or as one or more cardiac
stimulation electrodes. Electrodes may be used for cardiac pacing,
defibrillation, cardioversion, sensing, stimulation and/or
mapping.
[0125] Energy transfer elements or conductive elements may comprise
needles designed to penetrate tissues such as fat and muscle. For
example, energy transfer elements or conductive elements may be
designed to penetrate fat on the heart thereby allowing the energy
transfer elements or conductive elements to reach cardiac tissue.
The needles may allow fluids such as conductive fluids, chemicals
such as ablation chemicals, drugs, biological agents and/or cells
to pass through. The needles may allow a vacuum or suction to pass
through.
[0126] In addition, the dissector 10 may include components for
other features besides ablation. For example, the dissector 10 may
include means for tracking the position of the device 10 in a body
(e.g., tracking the distal portion 16). An example of a disclosure
of such a tracking means is described in U.S. Patent Application
Publication US 2006/0229594 A1 (Francischelli et al.), and is
herein incorporated by reference in its entirety. Alternatively, or
additionally, the dissector 10 may include any other desired
features. For example, the dissector 10 may include any of the
following features: sensing capabilities, imaging capabilities,
fluid transfer (e.g., hydration and/or desiccation) capabilities,
aeration capabilities, and cutting capabilities (e.g., cutting tool
included on distal portion). Other suitable capabilities are also
contemplated by the present invention.
[0127] The next step in such a method is that the guide member 194
is removed from the ablation device 222. The dissector 10 and guide
member 194 are then completely removed from the patient. Ablating
energy is then delivered to the ablation device 222 to ablate
tissue. Following the ablation procedure, the ablation device 222
is withdrawn or removed from the patient. In the exemplary method
illustrated in FIGS. 30-36, the jaws 224 would be removed from the
pulmonary veins 216, and the ablation device 222 would be withdrawn
back through the thoracotomy 210 and out of the body.
[0128] Without reference to any particular figures, in general, the
present invention contemplates using the dissector 10 as part of a
system for dissecting tissue and/or guiding a medical device to a
desired physiological location. The system may comprise: a
dissecting/guiding device 10, comprising: an elongate shaft 12
comprising a proximal portion 18 and a distal portion 16, wherein
the distal portion 16 comprises a plurality of segments that
articulate with respect to one another; a handle 14 attached to the
proximal portion 18 of the shaft 12, wherein the handle 14
comprises controls for articulating the plurality of segments of
the distal portion 16 of the shaft 12 with respect to one another;
and a guide wire tube 68 through at least a portion of the length
of the dissecting/guiding device 10, wherein the guide wire tube 68
comprises proximal and distal ends each having an opening; a guide
wire that may be fed into the proximal end of the guide wire tube
68, through the guide wire tube 68 and out through the distal
opening of the guide wire tube 68; and a guide member 194
comprising an elongate structure with two ends, wherein a first end
may attach to a distal end of the guide wire and a second end that
may attach to a medical device, such that when the guide wire, with
the medical device attached, is retracted back through the guide
wire tube 68, the medical device is guided to a desired
physiological location.
[0129] FIGS. 30-36, discussed above, demonstrate using the
dissector 10 to dissect pericardial reflection tissue and to place
an ablation device to treat atrial fibrillation. However, the
present invention also contemplates using the dissector 10 more
broadly during other surgical procedures performed to treat other
conditions. Therefore, more broadly, the present invention includes
a method of surgical dissection of tissue with a dissector 10
comprising: an elongate shaft 12 comprising a proximal portion 18
and a distal portion 16, wherein the distal portion 16 comprises a
plurality of segments that articulate with respect to one another
and the plurality of segments includes a distal segment 20 having a
distal end; and a handle 14 attached to the proximal portion 18 of
the shaft 12, wherein the handle 14 comprises controls for
articulating the plurality of segments of the distal portion 16 of
the shaft 12 with respect to one another, comprising the steps of:
positioning the distal end of the dissector 10 in a body; advancing
the distal end through the body to dissect tissue; and
simultaneously articulating the plurality of segments with respect
to one another. The distal end may include an illumination source
32, and the method may further comprise the step of visually
locating the distal portion 16 of the elongate shaft 12 by
observing visible energy from the illumination source 32 passing
through tissue, or may further comprise the step of differentiating
tissue by observing visible energy from the illumination source 32
through tissue.
[0130] The present invention also includes a method of guiding a
second device to a desired physiological location with a first
device comprising: an elongate shaft 12 comprising a proximal
portion 18 and a distal portion 16, wherein the distal portion 16
comprises a plurality of segments that articulate with respect to
one another and the plurality of segments includes a distal segment
20 having a distal end; a handle 14 attached to the proximal
portion 18 of the shaft 12, wherein the handle 14 comprises
controls for articulating the plurality of segments of the distal
portion 16 of the shaft 12 with respect to one another; and a guide
wire tube 68 having a proximal and a distal end, wherein the guide
wire tube 68 is disposed along at least a portion of the length of
the first device and the guide wire tube 68 has openings at both
the proximal and distal ends, comprising the steps of: inserting
the first device, distal end first, into a first opening in a body
with the plurality of segments of the distal portion in a
substantially straight configuration; advancing the distal end
through the body; articulating the plurality of segments with
respect to one another to position the distal portion in a desired
physiological location; feeding a guide wire, having a proximal and
a distal end, into the proximal opening of the guide wire tube,
distal end first, and through the guide wire tube until the distal
end of the guide wire comes out the distal opening of the guide
wire tube in the distal end of the first device; connecting the
second device to the distal end of the guide wire; and pulling the
guide wire back through the first device and thereby pulling the
second device adjacent the distal end of the first device at or
near a desired physiological location. The method may further
comprise the step of removing the first device through the first
opening. Prior to the step of removing the first device, the distal
portion of the first device may be returned to the substantially
straight configuration. The method of guiding may further comprise
the steps of: disconnecting the second device from the guide wire;
and removing the first device and the guide wire through the first
opening. The second device in the method may be inserted into the
body through a second opening in order to connect the second device
to the guide wire. If the distal end includes an illumination
source 32, the method may further comprise the step of visually
locating the distal end of the elongate shaft 12 by observing
visible energy from the illumination source 32 passing through
tissue. The illumination source 32 may be turned off and on. If the
first device further comprises an articulation lock mechanism for
maintaining the distal portion 16 of the device in a desired
articulated configuration, the method may further comprise the step
of locking the distal portion 16 in the articulated position while
the distal portion 16 is in the desired physiological location.
Additionally, with the presence of an articulation lock mechanism
(i.e., control wheel lock), lock could be unlocked to allow the
distal portion 16 of the first device to be returned to the
substantially straight configuration, particularly prior to removal
from through the first opening. If the first device further
comprises a guide wire lock that can maintain the position of the
guide wire in the guide wire tube 68, the method may further
comprise the step of locking the guide wire in a position in the
guide wire tube 68 after the step of pulling the guide wire back
through the first device.
[0131] A method combining the steps of dissection and guiding of a
second device is also contemplated by the present invention.
[0132] The dissector 10 and its components, as well as the other
parts of the system disclosed, are preferably made of biocompatible
materials such as stainless steel, biocompatible epoxy or
biocompatible plastic. Preferably, a biocompatible material prompts
little allergenic response from the patient's body and is resistant
to corrosion from being placed within the patient's body.
Furthermore the biocompatible material preferably does not cause
any additional stress to the patient's body, for example, it does
not scrape detrimentally against any element within the surgical
cavity.
[0133] It will be appreciated by those skilled in the art that
while the invention has been described above in connection with
particular embodiments and examples, the invention is not
necessarily so limited, and that numerous other embodiments,
examples, uses, modifications and departures from the embodiments,
examples and uses are intended to be encompassed by the claims
attached hereto. The entire disclosure of each patent and
publication cited herein is incorporated by reference, as if each
such patent or publication were individually incorporated by
reference herein.
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