U.S. patent application number 11/058845 was filed with the patent office on 2006-03-02 for method and apparatus for controlled contraction of soft tissue.
Invention is credited to Stuart D. Edwards, Gary S. Fanton, Ronald G. Lax.
Application Number | 20060047331 11/058845 |
Document ID | / |
Family ID | 22899634 |
Filed Date | 2006-03-02 |
United States Patent
Application |
20060047331 |
Kind Code |
A1 |
Lax; Ronald G. ; et
al. |
March 2, 2006 |
Method and apparatus for controlled contraction of soft tissue
Abstract
An apparatus and method are provided for control contraction of
tissue that includes collagen fibers. The apparatus includes a
handpiece, and an electrode with an electrode proximal end
associated with the handpiece. A distal end of the electrode has a
geometry that delivers a controlled amount of energy to the tissue
for a desired contraction of the collagen fibers. This is achieved
while dissociation and breakdown of the collagen fibers is
minimized. The handpiece, with electrode, is adapted to be
introduced through an operating cannula in percutaneous
applications. Additionally, an operating cannula may be included in
the apparatus and be attached to the handpiece. The apparatus and
method provides for a desired level of contraction of collagen soft
tissue without dissociation or breakdown of collagen fibers.
Inventors: |
Lax; Ronald G.; (Port
Orange, FL) ; Fanton; Gary S.; (Portola Valley,
CA) ; Edwards; Stuart D.; (Corral de Tierra,
CA) |
Correspondence
Address: |
MORRISON & FOERSTER, LLP
555 WEST FIFTH STREET
SUITE 3500
LOS ANGELES
CA
90013-1024
US
|
Family ID: |
22899634 |
Appl. No.: |
11/058845 |
Filed: |
February 15, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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09664473 |
Sep 18, 2000 |
|
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11058845 |
Feb 15, 2005 |
|
|
|
08696051 |
Aug 13, 1996 |
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|
09664473 |
Sep 18, 2000 |
|
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|
08637095 |
Apr 24, 1996 |
6482204 |
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08696051 |
Aug 13, 1996 |
|
|
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08389924 |
Feb 16, 1995 |
5569242 |
|
|
08637095 |
Apr 24, 1996 |
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08238862 |
May 6, 1994 |
5458596 |
|
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08389924 |
Feb 16, 1995 |
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Current U.S.
Class: |
607/99 |
Current CPC
Class: |
A61B 2018/143 20130101;
A61B 18/148 20130101; A61B 2018/1472 20130101; A61B 2018/00702
20130101; A61N 1/40 20130101; A61B 2018/00023 20130101; A61B
2018/00083 20130101; A61B 2018/1497 20130101; A61B 2018/00791
20130101; A61B 2018/00452 20130101; A61B 2018/1861 20130101 |
Class at
Publication: |
607/099 |
International
Class: |
A61F 7/00 20060101
A61F007/00; A61F 7/12 20060101 A61F007/12 |
Claims
1. A method utilizing RF energy for a dermatological application,
said method comprising: providing an apparatus comprising an RF
energy source, a treatment device and at least one electrode
coupled to the treatment device, said electrode having an electrode
surface for delivering RF energy from the RF energy source;
positioning the electrode surface on a skin surface; applying RF
energy to a target tissue; heating the target tissue with RF energy
while avoiding ablation of the target tissue; and contracting
collagen fibers in the target tissue.
2. The method of claim 1 further comprising delivering a fluid to
the skin surface such that the electrode surface is in contact with
the fluid.
3. The method of claim 2 wherein the fluid is a gel.
4. The method of claim 2 wherein the fluid is a cooling fluid so as
to minimize thermal damage to the skin surface.
5. The method of claim 1 wherein said applying RF energy comprises
applying RF energy to a target tissue more than 1 mm below the skin
surface.
6. The method of claim 1 wherein the RF energy source is coupled to
the treatment device.
7. A method utilizing RF energy, said method comprising: providing
an apparatus comprising an RF energy source, a treatment device and
at least one electrode coupled to the treatment device, said
electrode having an electrode surface for delivering RF energy from
the RF energy source; positioning the electrode surface on a skin
surface; applying RF energy to a target tissue; heating without
significantly ablating the target tissue with RF energy such that
the temperature of the target tissue does not exceed about
75.degree. C.; and contracting collagen fibers in the target tissue
to achieve a cosmetic effect.
8. A treatment method utilizing RF energy, said treatment method
comprising: providing an apparatus comprising an RF energy source,
a treatment device and at least one electrode coupled to the
treatment device, said electrode having an electrode surface for
delivering RF energy from the RP energy source; positioning the
electrode surface on a tissue surface; applying RF energy to a
target tissue below the tissue surface; heating the target tissue
with RF energy while avoiding ablation of the target tissue; and
contracting collagen fibers in the target tissue.
9. The treatment method of claim 8 wherein said heating the target
tissue comprises heating the target tissue while completely
avoiding ablation of the target tissue.
10. A method utilizing RF energy for a cosmetic application, said
method comprising: providing an apparatus comprising an RF energy
source, a treatment device and at least one electrode coupled to
the treatment device, said electrode having an electrode surface
for delivering RF energy from the RF energy source; delivering a
fluid to a skin surface; positioning the electrode surface such
that it is in contact with the fluid; delivering RF energy from the
electrode surface to a target tissue below the skin surface; and
heating the target tissue with RF energy to achieve at least one
effect, said effect comprising contracted collagen fibers in the
target tissue.
11. The method of claim 10 wherein said heating the target tissue
comprises heating the target tissue with RF energy such that the
temperature of the target tissue does not exceed about 90.degree.
C.
12. The method of claim 10 wherein the fluid is a gel.
13. The method of claim 10 wherein the fluid is a cooling fluid so
as to minimize thermal damage to the skin surface.
14. A treatment method for applying RF energy to a target tissue
without significantly ablating the target tissue, said treatment
method comprising: providing a system having an RF energy source, a
microprocessor, at least one electrode for delivering RF energy and
a temperature sensor associated with the electrode; measuring the
temperature of the electrode with the temperature sensor; providing
the temperature of the electrode to the microprocessor; and
determining whether to deliver RF energy from the electrode
depending on the provided temperature.
15. A system for applying RF energy to treat tissue, said system
comprising: an RF energy source; and a treatment device associated
with the RF energy source, said treatment device comprising an
electrically conductive material and a non-electrically conductive
material, wherein the non-electrically conductive material is
configured to extend along a surface of the tissue to be treated
and to maintain the electrically conductive material from directly
contacting the tissue.
16. The system of claim 15 wherein the non-electrically conductive
material comprises at least one polymer.
17. The system of claim 16 wherein the at least one polymer is
polyimide.
18. A system for contracting collagen fibers in a target tissue
with RF energy from an RF energy source, said system comprising: an
electrically conductive material for transmitting RF energy from
the RF energy source; and a non-electrically conductive material
wherein the non-electrically conductive material is configured
between the electrically conductive material and the target tissue
so as to maintain the electrically conductive material from
directly contacting the target tissue.
19. A system for applying RF energy to a target tissue, said system
comprising: an RF energy source; and a treatment device comprising
an electrically conductive surface area for delivering RF energy
from the RF energy source to the target tissue so as to contract
collagen fibers in the target issue, wherein said treatment device
is configurable to provide a plurality of surface areas.
20. A system for controllably contracting collagen fibers in a
target tissue with RF energy to achieve a cosmetic effect, said
system comprising: an RF energy source; a treatment device; at
least one cable for connecting the RF energy source to the
treatment device; and at least one electrode coupled to the
treatment device, said electrode having an electrode surface
configured to be positioned on a skin surface so as to deliver RF
energy from the RF energy source to the target tissue while
avoiding ablation of the target tissue.
21. The system of claim 20 further comprising a device for
providing a cooling fluid so as to minimize thermal damage to the
skin surface.
22. The system of claim 20 wherein the electrode surface is
substantially planar.
23. A system for applying RF energy to a target tissue without
significantly ablating the target tissue, said system comprising:
an RF energy source; a handpiece; at least one cable for connecting
the RF energy source to the handpiece; at least one electrode for
delivering RF energy, said electrode coupled to the handpiece; a
temperature sensor associated with the electrode, said temperature
sensor configured to measure the temperature of the electrode; and
a microprocessor configured to receive the temperature of the
electrode from the temperature sensor and to determine whether to
deliver RF energy from the electrode depending on the received
temperature.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 09/664,473, filed Sep. 18, 2000, which is a continuation of
U.S. application Ser. No. 08/696,051, filed Aug. 13, 1996, which is
a continuation-in-part of U.S. application Ser. No. 08/637,095,
filed Apr. 24, 1996, now U.S. Pat. No. 6,482,204, which is a
continuation of U.S. application Ser. No. 08/389,924, filed Feb.
16, 1995, now U.S. Pat. No. 5,569,242, which is a continuation of
Ser. No. 08/238,862, filed May 6, 1994, now U.S. Pat. No.
5,458,596.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to the contraction of soft
tissue, and more particularly, to the compaction of soft collagen
tissue with minimal dissociation of collagen tissue.
[0004] 2. Description of the Related Art
[0005] Instability of peripheral joints has long been recognized as
a significant cause of disability and functional limitation in
patients who are active in their daily activities, work or sports.
Diarthrodial joints of musculoskeletal system have varying degrees
of intrinsic stability based on joint geometry and ligament and
soft tissue investment. Diarthrodial joints are comprised of the
articulation of the ends of bones and their covering of hyaline
cartilage surrounded by a soft tissue joint capsule that maintains
the constant contact of the cartilage surfaces. This joint capsule
also maintains within the joint the synovial fluid that provides
nutrition and lubrication of the joint surfaces. Ligaments are soft
tissue condensations in or around the joint capsule that reinforce
and hold the joint together while also controlling and restricting
various movements of the joints. The ligaments, joint capsule, and
connective tissue are largely comprised of collagen.
[0006] When a joint becomes unstable, its soft tissue or bony
structures allow for excessive motion of the joint surfaces
relative to each other and in directions not normally permitted by
the ligaments or capsule. When one surface of a joint slides out of
position relative to the other surface, but some contact remains,
subluxation occurs. When one surface of the joint completely
disengages and loses contact with the opposing surface, a
dislocation occurs. Typically, the more motion a joint normally
demonstrates, the more inherently loose the soft tissue investment
is surrounding the joint. This makes some joints more prone to
instability than others. The shoulder, (glenohumeral) joint, for
example, has the greatest range of motion of all peripheral joints.
It has long been recognized as having the highest subluxation and
dislocation rate because of its inherent laxity relative to more
constrained "ball and socket" joints such as the hip.
[0007] Instability of the shoulder can occur congenitally,
developmentally, or traumatically and often becomes recurrent,
necessitating surgical repair. In fact subluxations and
dislocations are a common occurrence and cause for a large number
of orthopedic procedures each year. Symptoms include pain,
instability, weakness, and limitation of function. If the
instability is severe and recurrent, functional incapacity and
arthritis may result. Surgical attempts are directed toward
tightening the soft tissue restraints that have become
pathologically loose. These procedures are typically performed
through open surgical approaches that often require hospitalization
and prolonged rehabilitation programs.
[0008] More recently, endoscopic (arthroscopic) techniques for
achieving these same goals have been explored with variable
success. Endoscopic techniques have the advantage of being
performed through smaller incisions and therefore are usually less
painful, performed on an outpatient basis, are associated with less
blood loss and lower risk of infection and have a more cosmetically
acceptable scar. Recovery is often faster postoperatively than
using open techniques. However, it is often more technically
demanding to advance and tighten capsule or ligamentous tissue
arthroscopically because of the difficult access to pathologically
loose tissue and because it is very hard to determine how much
tightening or advancement of the lax tissue is clinically
necessary. In addition, fixation of advanced or tightened soft
tissue is more difficult arthroscopically than through open
surgical methods.
[0009] Collagen connective tissue is ubiquitous in the human body
and demonstrates several unique characteristics not found in other
tissues. It provides the cohesiveness of the musculoskeletal
system, the structural integrity of the viscera as well as the
elasticity of integument. These are basically five types of
collagen molecules with Type I being most common in bone, tendon,
skin and other connective tissues, and Type III is common in
muscular and elastic tissues.
[0010] Intermolecular cross links provide collagen connective
tissue with unique physical properties of high tensile strength and
substantial elasticity. A previously recognized property of
collagen is hydrothermal shrinkage of collagen fibers when elevated
in temperature. This unique molecular response to temperature
elevation is the result of rupture of the collagen stabilizing
cross links and immediate contraction of the collagen fibers to
about one-third of their original lineal distention. Additionally,
the caliber of the individual fibers increases greatly, over four
fold, without changing the structural integrity of the connection
tissue.
[0011] There has been discussion in the existing literature
regarding alteration of collagen connective tissue in different
parts of the body. One known technique for effective use of this
knowledge of the properties of collagen is through the use of
infrared laser energy to effect tissue heating. The use of infrared
laser energy as a corneal collagen shrinking tool of the eye has
been described and relates to laser keratoplasty, as set forth in
U.S. Pat. No. 4,976,709. The importance controlling the
localization, timing and intensity of laser energy delivery is
recognized as paramount in providing the desired soft tissue
shrinkage effects without creating excessive damage to the
surrounding non-target tissues.
[0012] Radiofrequency (RF) electrical current has been used to
reshape the cornea. Such shaping has been reported by Doss in U.S.
Pat. Nos. 4,326,529; and 4,381,007. However, Doss was not concerned
with dissociating collagen tissue in his reshaping of the
cornea.
[0013] Shrinkage of collagen tissue is important in many
applications. One such application is the shoulder capsule. The
capsule of the shoulder consists of a synovial lining and three
well defined layers of collagen. The fibers of the inner and outer
layers extend in a coronal access from the glenoid to the humerus.
The middle layer of the collagen extends in a sagittal direction,
crossing the fibers of the other two layers. The relative thickness
and degree of intermingling of collagen fibers of the three layers
vary with different portions of the capsule. The ligamentous
components of the capsule are represented by abrupt thickenings of
the inner layer with a significant increase in well organized
coarse collagen bundles in the coronal plane.
[0014] The capsule functions as a hammock-like sling to support the
humeral head. In pathologic states of recurrent traumatic or
developmental instability this capsule or pouch becomes attenuated
and the capsule capacity increases secondary to capsule redundance.
In cases of congenital or developmental multi-directional laxity,
an altered ratio of type I to type III collagen fibers may be
noted. In these shoulder capsules a higher ratio of more elastic
type III collagen has been described.
[0015] There is a need for a method and apparatus to effect
controlled lineal contraction or shrinkage of collagen fibers to
provide a multitude of non-destructive and beneficial structural
changes and corrections within the body. More particularly with
regard to the shoulder capsule, current surgical techniques involve
cutting or advancing the shoulder capsule to eliminate capsular
redundance or to otherwise tighten the ligamous complex.
Accordingly, there is a need to control shrinkage of the capsule by
utilizing the knowledge of the properties of collagen in response
to a specific level of thermal application.
SUMMARY OF THE INVENTION
[0016] It is an object of the present invention to provide a method
and apparatus to control the duration and application of thermal
energy to a tissue site made that includes collagen soft tissue, a
desired level of contraction of collagen fibers is obtained while
dissociation and breakdown of the collagen fibers is minimized.
[0017] Another object of the present invention is to use RF heating
in a fluid environment to control thermal spread to a tissue that
includes collagen soft tissue, and a desired contraction of
collagen fibers is obtained while minimizing dissociation and
breakdown of the collagen fibers.
[0018] Yet another object of the present invention is to provide a
device directed to collagen connective tissue shrinkage by the use
of RF heating to a temperature profile of 43 to 90 degrees
centigrade.
[0019] Another object of the present invention is to provide a
device directed to collagen connective tissue shrinkage by the use
of RF heating to a temperature profile of 43 to 75 degrees
centigrade.
[0020] Still a further object of the present invention is to
provide a device directed to collagen connective tissue shrinkage
by the use of the RF heating to a temperature profile of 45 to 60
degrees centigrade.
[0021] Another object of the present invention is to provide an
apparatus which delivers RF energy through an endoscopically guided
handpiece in a fluid environment to obtain maximum contraction of
collagen soft tissue while minimizing dissociation and breakdown of
the collagen tissue.
[0022] Yet another object of the present invention is to provide an
apparatus that provides for the maximum amount of collagen
contraction without dissociation of the collagen structure.
[0023] Another object of the present invention is to provide an
apparatus to deliver a controlled amount of RF energy to the
collagen soft tissue of a joint in order to contract and restrict
the soft tissue elasticity and improve joint stability.
[0024] A further object of the present invention to provide an
apparatus and method that reduces redundancy of the shoulder
capsule and improves stability to the joint.
[0025] These and other objects of the invention are obtained with
an apparatus for control contraction of tissue that includes
collagen fibers. The apparatus include a handpiece, and an
electrode with an electrode proximal end that is associated with
the handpiece. A distal end of the electrode has a geometry that
delivers a controlled amount of energy to the tissue in order to
achieve a desired contraction of the collagen fibers. This is
achieved while dissociation and breakdown of the collagen fibers is
minimized.
[0026] The handpiece, with electrode, is adapted to be introduced
through an operating cannula in percutaneous applications.
Additionally, it may be desirable to include as part of the
apparatus an operating cannula. In this instance, the operating
cannula has a proximal end that attaches to the handpiece, and a
distal end that is adapted to be introduced into a body structure.
The electrode is positioned within the operating cannula, and
extendable beyond the distal end of the cannula when thermal energy
is delivered to the tissue.
[0027] It is recognized that the delivery of the thermal energy to
the tissue should be delivered in such a way that none of the
tissue is ablated. Additionally, the delivery is achieved without
dissociating or breaking down the collagen structure. This can be
accomplished in different ways, but it has been discovered that an
electrode with radiused edges at its distal end is suitable to
obtain this result. The present invention is applicable to a number
of different anatomical sites. Depending on the anatomy, it may be
necessary to deflect the distal end of the electrode to reach the
desired site. Additionally, one side of the electrode may include
an insulating layer so that thermal energy is only delivered to the
intended tissue, and not a tissue in an adjacent relationship to
the area of treatment.
[0028] In certain instances it is desirable to be able to vary the
length of the electrode conductive surface which delivers the
thermal energy to the tissue. For this purpose, an adjustable
insulator, that is capable of movement along the longitudinal axis
of the electrode, provides a way of adjusting the length of
electrode conductive surface.
[0029] Memory metals can be used for the electrode construction. An
advantage of memory metals is that with the application of heat to
the metal, it can be caused to be deflected. This is particularly
useful for deflecting the distal end of the electrode.
[0030] The electrode can include a central lumen that receives an
electrolytic solution from an electrolytic source. A plurality of
apertures are formed in the distal end of the electrode and deliver
the flowing electrolytic fluid to the tissue. Instead of an
electrolytic solution, an electrolytic gel can also be introduced
through the electrode.
[0031] In one embodiment of the invention, the electrode is
partially surrounded by an insulating housing in order to position
the electrode in an adjacent but spaced relationship to the tissue.
A portion of the insulating housing rides on the tissue, and
creates the equivalent of a partial dam for electrolytic solution
introduced through the electrode and towards the tissue. A cuff is
disposed about the insulating housing. The cuff and insulating
housing together create a return electrolytic solution channel for
the removal of solution flowing out of the dam and away from the
tissue site.
[0032] The handpiece of the invention can be connected, with a
cable, to an RF energy source. A closed loop feedback system can be
included and coupled to a temperature sensor on the electrode and
the RF energy source. Temperature at the electrode can be
monitored, and the power of the RF energy source adjusted to
control the amount of energy that is delivered to the tissue.
[0033] The present invention has wide spread application to many
different anatomical locations. It can be utilized for controlled
contraction of collagen soft tissue of a joint capsule,
particularly the gleno-humoral joint capsule of the shoulder, to
treat herniated discs, the meniscus of the knee, for dermatology,
to name just a few.
[0034] In one embodiment of the invention, RF heating in a fluid or
saline environment is used to control thermal spread to soft
collagen tissue. The RF energy can be delivered through an
endoscopically guided handpiece under arthroscopic visualization by
the surgeon. In the temperature range of 43 to 90 degrees C.,
maximum collagen contraction is achieved. Additional temperature
ranges are 43 to 75 degrees C., and 45 to 60 degrees C. Lower
temperatures do not provide maximum thermal induced contracture of
the collagen fibrils. Greater temperatures create excessive
destruction and disintegration of the collagen fibrillar pattern.
Thus, the present invention is a method and apparatus which
accurately controls the application of heat within a desired
thermal range. This heat is delivered the collagen soft tissue,
thereby contracting and restricting the soft tissue elasticity and
improving stability.
DESCRIPTION OF THE DRAWINGS
[0035] FIG. 1 is a perspective plan view of an apparatus for
control contraction of tissue that includes collagen fibers,
including a handpiece and an electrode, according to the
invention.
[0036] FIG. 2 is a perspective plan view of a distal end of the
electrode with all edges radiused according to the invention.
[0037] FIG. 3 is a side view of the distal end of the electrode of
FIG. 2.
[0038] FIG. 4 is a sectional view of the deflected electrode with a
resistive heating element positioned in an interior lumen of the
electrode according to the invention.
[0039] FIG. 5 is a perspective plan view of the apparatus for
control contraction of tissue with collagen fibers with a
handpiece, electrode and an operating cannula according to the
present invention.
[0040] FIG. 6 is a close up perspective plan view of the distal end
of the electrode of the apparatus of FIG. 5 according to the
invention.
[0041] FIG. 7 is a perspective plan view of an electrode with a
steering wire positioned on the exterior of the electrode according
to the invention.
[0042] FIG. 8 is a sectional view of an electrode with a lumen and
a plug that is attached to the electrode distal end according to
the invention.
[0043] FIG. 9 is a cross sectional view of an electrode with fluid
flowing through an interior lumen of the electrode according to the
invention.
[0044] FIG. 10 is a cross sectional view of an RF electrode
structure with an insulating housing surrounding a portion of an
electrode, and a cuff surrounding the insulating housing according
to the invention.
[0045] FIG. 11 is a block diagram of a fluid control system useful
with the electrode structure of FIG. 10 according to the
invention.
[0046] FIG. 12 is a perspective plan view of a handpiece, an
electrode and a sleeve that slides across the surface of the
electrode to vary the amount of electrode conductive surface
according to the invention.
[0047] FIG. 13 is a sectional view of an electrode with an oval
cross section and the heating zone in the tissue according to the
invention.
[0048] FIG. 14 is a sectional view of a handle, electrode,
operating cannula and a viewing scope, with the viewing scope and
electrode positioned in the operating cannula according to the
invention.
[0049] FIG. 15 is a cross sectional view of the device of FIG. 14,
taken along the lines 15-15 according to the invention.
[0050] FIG. 16 is a perspective plan view of an electrode distal
end with temperature sensors positioned in the distal end according
to the invention.
[0051] FIG. 17 is a block diagram of a closed loop feedback system
according to the invention.
[0052] FIG. 18 is a perspective plan view of a roller element
mounted at an electrode distal end according to the invention.
[0053] FIG. 19 is a drawing of the right glenohumeral
capsuloligamentous complex.
[0054] FIG. 20 is a drawing of a loose joint capsule.
[0055] FIG. 21 is a schematic drawing of the apparatus of the
invention with an electrode supplying thermal energy to a joint
structure.
[0056] FIG. 22 is a sectional view of a disc positioned between two
vertebrae.
[0057] FIG. 23 is a schematic drawing of the apparatus of the
invention with an electrode supplying thermal energy to a herniated
disc.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0058] Referring now generally to FIG. 1, an apparatus for control
contraction of tissue that includes collagen fibers is generally
denoted as 10. Apparatus 10 includes a handpiece 12 that is
preferably made of an insulating material. Types of such insulating
materials are well known in those skilled in the art. An electrode
14 is associated with handle 12 at a proximal end 16 of electrode
14, and may even be attached thereto. A distal end 18 of electrode
14 has a geometry that delivers a controlled amount of energy to
the tissue in order to achieve a desired level of contraction of
the collagen fibers. Contraction is achieved while dissociation and
breakdown of the collagen fibers is minimized.
[0059] Electrode 14 can have be a flat elongated structure that is
easily painted across a tissue without "hanging up" on any section
of the tissue. In one geometry of electrode 14, all edges 20 of
distal end 18 are radiused, as illustrated in FIGS. 2 and 3. Distal
end 18 can have a variety of geometric configurations. One such
geometry is a disc shaped geometry without square edges. Electrode
14 can be made of a number of different materials including but not
limited to stainless steel, platinum, other noble metals and the
like. Electrode 14 can be made of a memory metal, such as nickel
titanium, commercially available from Raychem Corporation, Menlo
Park, Calif. In FIG. 4, a resistive heating element 22 can be
positioned in an interior lumen of electrode 14. Resistive heating
element can be made of a suitable metal that transfers heat to
electrode 14, causing electrode distal end 18 to become deflected
when the temperature of electrode 14 reaches a level that the
memory metal is caused to deflect, as is well known in the art. Not
all of electrode 14 need be made of the memory metal. It is
possible that only electrode distal end 18 be made of the memory
metal in order to effect the desired deflection. There are other
methods of deflecting electrode 18, as will be more fully discussed
and described in a later section of this specification.
[0060] Apparatus 10, comprising handpiece 12 and electrode 14, is
adapted to be introduced through an operating cannula for
percutaneous applications. It will be appreciated that apparatus 10
may be used in non-percutaneous applications and that an operating
cannula is not necessary in the broad application of the
invention.
[0061] As illustrated in FIGS. 5 and 6, apparatus 10 can also
include, as an integral member, an operating cannula 24 which can
be in the form of a hyperdermic trocar with dimensions of about 3
to 6 mm outside diameter, with tubular geometries such as those of
standard commercially available operating cannulas. Operating
cannula 24 can be made of a variety of biocompatible materials
including but not limited to stainless steel, and the like.
[0062] Operating cannula 24 has a proximal end that attaches to
handpiece 12 and it can have a sharp or piercing distal end 26 that
pierces a body structure in order to introduce electrode 14 to a
desired site. Electrode 14 is positioned within an interior lumen
of operating cannula 24 and is extendable beyond distal end 26 in
order to reach the desired tissue site. Electrode 14 can be
advanced and retracted in and out of operating cannula 24 by
activating a deployment button 28 which is located on the exterior
of handle 12. Deployment button 28 is preferably activated by the
operator merely by sliding it, which causes electrode 14 to advance
in a direction away from distal end 26 of operating cannula 24.
Deployment button 28 can be pulled back, causing a retraction of
electrode 14 towards distal end 26. In many instances, electrode 14
will be retracted to be positioned entirely within operating
cannula 14. Electrode 14 can also deployed with fluid hydraulics,
pneumatics, servo motors, linear actuators, and the like.
[0063] An electrical and/or fluid flow cable 28 attaches to handle
12 and provides the necessary connection of apparatus 10 to a
suitable energy source and/or a source of fluid, which may be an
electrolytic solution or an electrolytic gel. An electrolytic
solution, for purposes of this invention, is one that increases the
transfer of thermal energy from electrode 14 to a tissue. Suitable
electrolytic solutions include but are not limited to saline
solution and the like.
[0064] A variety of energy sources can be used with the present
invention to transfer thermal energy to the tissue that includes
collagen fibers. Such energy sources include but are not limited to
RF, microwave, ultrasonic, coherent light and thermal transfer.
[0065] When an RF energy source is used, the physician can activate
the energy source by the use of a foot switch 30 that is associated
with handle 12 and electrode 14. Significantly, a controlled amount
of RF energy is delivered so that there is an effective transfer of
thermal energy to the tissue site so that the thermal energy
spreads widely through the tissue but does not cause a dissociation
or breakdown of the collagen fibers.
[0066] For many applications, it is necessary to have electrode
distal end 18 to become deflected (FIG. 6). This can be achieved
with the use of memory metals, or it can be accomplished
mechanically. A steering wire, or other mechanical structure, is
attached to either the exterior or interior of electrode 14. A
deflection button 32, located on handle 12, is activated by the
physician, causing steering wire 34 (FIG. 7) to tighten, and impart
an retraction of electrode 14, resulting in a deflection of
electrode distal end 18. It will be appreciated that other
mechanical mechanisms can be used in place of steering wire 34. The
deflection may be desirable for tissue sites that have difficult
access, and it is necessary to move about a non-linear tissue. By
deflecting electrode distal end 18, the opportunity to provide more
even thermal energy to a tissue site is achieved, and the
possibility of ablating or dissociation of collagen material is
greatly reduced.
[0067] As shown in FIG. 7, steering wire 34 attaches to a flat
formed on the exterior of electrode 14. Wire EDM technology can be
used to form the flat on electrode 14. A "T" bar configuration is
illustrated in FIG. 7. Chemical etching may be used to create the
"T" bar. Steering wire 34 need not be an actual wire. It can also
be a high tensile strength cord such as Kevlar. Steering wire 34
can be made of stainless steel flat wire, sheet material, and the
like.
[0068] Electrode 14 can be tubular in nature with a central lumen.
Electrode distal end 18 can include a conductive plug that is
sealed to electrode distal end 18 by welding, e-beam, laser, and
the like.
[0069] In FIG. 9, Electrode 14 can include an electrical insulation
layer 38 formed on a back side of electrode 14 which is intended to
minimize damage to tissue areas that are not treated. For example;
when electrode 14 is introduced into a tight area, and only one
surface of the tight area is to be treated, then it desirable to
avoid delivering thermal energy to other tissue site areas. The
inclusion of insulation layer 38 accomplishes this result. Suitable
insulation materials include but are not limited to polyimide,
epoxy varnish, PVC and the like. Electrode 14 includes a conductive
surface 40 which does not include insulation layer 38.
[0070] A plurality of apertures 42 are formed in electrode 14 to
introduce a flowing fluid 44 through an interior lumen of electrode
14 and to the tissue site. The flowing fluid can be an electrolytic
solution or gel, including but not limited to saline. The
electrolyte furnishes an efficient electrical path and contact
between electrode 14 and the tissue to be heated.
[0071] Referring now to FIG. 10, electrode 14 includes a central
lumen for receiving an electrolytic solution 44 from an
electrolytic source. Electrolytic solution 44 flows from electrode
14 through a plurality of apertures 42 formed in conductive surface
40. An insulating housing 46 surrounds electrode 14, leaving only
conductive surface 40 exposed. Insulating housing 46 can be formed
of a variety of non-electrically conducting materials including but
not limited to thermoplastics, thermosetting plastic resins,
ceramics, and the like. Insulating housing 46 rides along the
surface of the tissue to be treated and positions conductive
surface 40 in an adjacent but spaced relationship with the tissue.
In this manner, there isn't direct contact of conductive surface 40
with the tissue, and the chance of dissociation or break down of
the collagen fibers is reduced. Insulating housing 46 creates a
partial dam 48 of electrolytic solution adjacent to the tissue.
Electrical energy is transferred from electrode 14 to electrolytic
solution 44, and from electrolytic solution 44 in dam 48 to the
tissue. A cuff 50 surrounds insulating housing 46. Cuff 50 may be
made of a variety of materials including but not limited to
thermoplastic, thermosetting plastic resins, ceramics and the like.
The respective dimensions of insulating housing 46 and cuff can
vary according to the specific application. For example, in
percutaneous applications, the dimensions will be smaller than for
those used in topical applications such as dermatology.
[0072] Cuff 50 and insulating housing 46 are closely positioned to
each other, but they are spaced in a manner to create a return
electrolytic solution channel 52. The used electrolyte solution may
either be released within a confined body area, such as the joint,
or not be returned to the tissue, but instead is removed.
[0073] Use of a cooled solution to deliver the thermal energy to
the tissue, instead of direct contact with conductive surface 40,
provides a more even thermal gradient in the tissue. Avoidance of
surface overheating can be accomplished. There is a more uniform
level of thermal energy applied to the tissue. Electrolytic
solution 44 may be cooled in the range of about 30 to 55 degrees
C.
[0074] Referring now to FIG. 1, electrolytic solution 44 is in a
holding container 54 and transferred through a fluid conduit 56 to
a temperature controller 58 which can cool and heat electrolytic
solution 44 to a desired temperature. A pump 60 is associated with
fluid conduit 56 to transfer fluid throughout the system and
delivers electrolytic solution 44 through handpiece 12 to electrode
14. Returning electrolytic fluid 44 passes through return
electrolytic solution channel 52, and is delivered to a waste
container 62. The flow rate of electrolytic solution can be in the
range of less than about 1 cc/min. to greater than 5 cc/second.
[0075] The area of electrode 14 that serves as conductive surface
44 can be adjusted by the inclusion of an insulating sleeve 64
(FIG. 12) that is positioned around electrode 14. Sleeve 64 is
advanced and retracted along the surface of electrode 14 in order
to provide increase or decrease the surface area of conductive
surface 44 that is directed to the tissue. Sleeve 64 can be made of
a variety of materials including but not limited to nylon,
polyimides, other thermoplastics and the like. The amount of
available conductive surface 44 available to deliver thermal energy
can be achieved with devices other than sleeve 64, including but
not limited to printed circuitry with multiple circuits that can be
individually activated, and the like.
[0076] Electrode 14 can have a variety of different geometric
configurations. In one embodiment, electrode 14 has an oval cross
section (FIG. 13). The oval cross section provides a greater
conductive surface 44 area that is in contact with the tissue. A
larger zone of heating to the tissue is provided. The thermal
gradient within the tissue is more even and the possible
dissociation or breakdown of the collagen fibers is reduced.
[0077] As illustrated in FIG. 14, operating cannula 24 includes a
viewing scope 66 which may be positioned above electrode 14 (FIG.
15). Viewing scope 66 provides a field of view 68, permitting the
surgeon to view while delivering energy to the tissue site and
contracting the tissue. Viewing scope 66 can include a bundle light
transmitting fibers and optical viewing elements. Alternatively,
the surgeon can view the procedure under arthroscopic
visualization.
[0078] Referring now to FIG. 16, one or more temperature sensors 70
can be positioned in electrode 14, particularly at electrode distal
end 18. Temperature sensor 70 can be a thermocouple, a thermistor
or phosphor coated optical fibers. Temperature sensor 70 can be
utilized to determine the temperature of electrode 14, particularly
at conductive surface 40, or temperature sensor 70 may be employed
to determine the temperature of the tissue site.
[0079] Additionally, the apparatus of the present invention can be
an RF energy delivery device to effect contraction of collagen soft
tissue while minimizing dissociation or breakdown of the collagen
fibers. As shown in FIG. 17 the apparatus for control contraction
of collagen soft tissue can include handpiece 12, electrode 14,
operating cannula 24, a cable 28 and an RF power source 72.
Suitable RF power sources are commercially available and well known
to those skilled in the art. In one embodiment of the invention RF
power source 72 has a single channel, delivering approximately 30
watts of RF energy and possess continued flow capability. A closed
loop feedback system, coupling temperature sensor 70 to RF energy
source 72 can be included. The temperature of the tissue, or of
electrode 14 is monitored, and the power of RF generator 72
adjusted accordingly. The physician can, if desired, override the
closed loop system. A microprocessor 74 can be included and
incorporated into the closed loop system switch power on and off,
as well as modulate the power. A suitable microprocessor is
commercially available and well known to those skilled in the art
of closed loop feedback systems. The closed loop system utilizes
microprocessor 74 to serve as a controller, watch the temperature,
adjust the RF power, look at the result, refed the result, and then
modulates the power.
[0080] Optionally positioned on electrode distal end 18 is a
conductive roller element 76 (FIG. 18). Conductive roller element
is rotatably mounted on electrode distal end 18 and can include a
plurality of projections 78. Roller element 76 is moved across the
tissue site, along with projections 78, to deliver the thermal
energy.
[0081] The present invention provides a method of contracting
collagen soft tissue. The collagen soft tissue is contracted to a
desired shrinkage level without dissociation and breakdown of the
collagen structure. It can be used in the shoulder, spine, cosmetic
applications, and the like. It will be appreciated to those skilled
in the art that the present invention has a variety of different
applications, not merely those specifically mentioned in this
specification. Some specific applications include joint capsules,
specifically the gleno-humoral joint capsule of the shoulder,
herniated discs, the meniscus of the knee, in the bowel, for hiatal
hernias, abdominal hernias, bladder suspensions, tissue welding,
DRS, and the like.
[0082] RF energy, thermal energy, is delivered to collagen soft
tissue. The thermal energy penetrates more than 1 mm through the
collagen soft tissue. The penetration can be as much as about 3 mm.
Electrode 14 is painted across the collagen soft tissue
sequentially until the maximum shrinkage occurs. In one embodiment,
the collagen soft tissue is contracted in an amount of about
two-thirds of its resting weight. A temperature range of about 43
to 90 degrees C. is preferred. More preferred, the temperature
range is about 43 to 75 degrees C. Still more preferred is a
temperature range of 45 to 60 degrees C.
[0083] In one specific embodiment of the invention, joint capsules
are treated to eliminate capsular redundance. More specifically,
the invention is utilized to contract soft collagen tissue in the
gleno-humoral joint capsule of the shoulder. The basic anatomy of
the gleno-humoral joint capsule of the shoulder is illustrated in
FIG. 19.
[0084] The apparatus of the present invention provides RF heating
in a fluid or saline environment to control thermal spread. RF
heating is applied to collagen connective tissue shrinkage in
temperature ranges of about 43 to 90 degrees C., 43 to 75 degrees
C. and 45 to 60 degrees C. The RF energy is delivered through
endoscopically guided handpiece 12 in a fluid or saline environment
within the joint. It can be under arthroscopic visualization by the
surgeon, or the apparatus can include a viewing device. The
invention accurately controls the application of heat within a
specific thermal range, and delivers thermal energy to collagen
soft tissue of the joint, thereby contracting and restricting the
soft tissue elasticity and improving joint stability. When applied
to the shoulder, there is capsular shrinkage of the gleno-humoral
joint capsule of the shoulder and a consequent contracture of the
volume, the interior circumference, of the shoulder capsule to
correct for recurrent instability symptoms. The degree of capsular
shrinkage is determined by the operating surgeon, based on severity
of preoperative symptoms and condition of the capsule at the time
of arthroscopic inspection. The maximum amount of collagen
contraction achieved is approximately two-thirds of its original
structure.
[0085] In FIG. 20, a loose capsule is illustrated. The apparatus
for control contraction of tissue of the present invention is
applied to a joint capsule (FIG. 21). Electrode distal end 18 is
painted across the surface of the collagen soft tissue. FIGS. 23
and 24 illustrate the application of the invention to a herniated
disc.
[0086] While embodiments and applications of this invention have
been shown and described, it will be apparent to those skilled in
the art that many more modifications than mentioned above are
possible without departing from the invention concepts herein. The
invention, therefore, is not to be restricted except in the spirit
of the appended claims.
* * * * *