CA2265981A1 - Method and apparatus for controlled contraction of soft tissue - Google Patents
Method and apparatus for controlled contraction of soft tissue Download PDFInfo
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- CA2265981A1 CA2265981A1 CA002265981A CA2265981A CA2265981A1 CA 2265981 A1 CA2265981 A1 CA 2265981A1 CA 002265981 A CA002265981 A CA 002265981A CA 2265981 A CA2265981 A CA 2265981A CA 2265981 A1 CA2265981 A1 CA 2265981A1
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- energy
- delivery device
- sensor
- energy delivery
- containing tissue
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N1/00—Electrotherapy; Circuits therefor
- A61N1/02—Details
- A61N1/04—Electrodes
- A61N1/06—Electrodes for high-frequency therapy
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N1/00—Electrotherapy; Circuits therefor
- A61N1/40—Applying electric fields by inductive or capacitive coupling ; Applying radio-frequency signals
- A61N1/403—Applying electric fields by inductive or capacitive coupling ; Applying radio-frequency signals for thermotherapy, e.g. hyperthermia
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/02—Radiation therapy using microwaves
- A61N5/04—Radiators for near-field treatment
Abstract
An apparatus for effecting change in at least a portion of a selected site of a collagen containing tissue that is at least partially adjacent to a fluid medium. The apparatus includes an energy delivery device configured to deliver a level of energy to the selected site of the collagen containing tissue. The energy delivery device includes a distal portion where a sensor is positioned.
The sensor provides a signal indicative of the thermal energy content of at least the selected site of the collagen containing tissue and the adjacent fluid medium to a feedback control unit. The signal is received by the feedback control system which adjusts the level of energy supplied to the energy delivery.
The sensor provides a signal indicative of the thermal energy content of at least the selected site of the collagen containing tissue and the adjacent fluid medium to a feedback control unit. The signal is received by the feedback control system which adjusts the level of energy supplied to the energy delivery.
Description
CA 0226~981 1999-03-16 METHOD AND APPARATUS FOR CONTROLLED
CONTRACTION OF SO~Y TISSUE
CROSS-REFERENCE TO RELATl~D APPLICATIONS
BACKGROUND OF THE INVENTION
Related Inventions This application is a continuation in part of Serial No. 08/637,095, filed April 24, 1996, entitled METHOD AND APPARATUS FO~ CONTROLLED
CONTRACTION OF SOFT TISSUE, which is a continuation of Serial No.
08/389,924, filed February 16, 1995, entitled METHOD AND APPARATUS
FOR CONTROLLED CONTRACTION OF SOFT TISSUE, which is a continuation of Serial No. 08/238,862, filed May 6, 1994, entitled METHOD
AND APPARATUS FOR CONTROLLED CONTRACTION OF SOFT
TISSUE.
Field ofthe Invention This invention relates generally to a method and apparatus for delivering thermal energy to a selected collagen cont~ining tissue and effecting a contraction of at least a portion of the collagen cont~ining tissue, and more particularly to a method and apparatus for contracting a collagen co~ ;"g tissue that is at least partially adj~c~nt to a fluid medium.
Description of the Related Art Instability of peripheral joints has long been recognized as a ~ignifir.~nt cause of disability and functional limitation in patients who are active in their daily activities, work or sports. Diarthrodial joints of the musculoskeletal system have varying degrees of intrinsic stability based on joint geometry and lig~m~nt and soft tissue investment Diarthrodial joints are comprised of the . .
CA 0226~981 1999-03-16 articulation of the ends of bones and their covering of hyaline cartilage surrounded by a soft tissue joint capsule that In~ the constant contact of the cartilage surfaces. This joint capsule also Ill~ c within the joint the synovial fluid that provides nutrition and lubrication of the joint surfaces.
~ .ig~ e~ s are soft tissue con-len~tions in or around the joint capsule that reinforce and hold the joint together while also controlling and restricting various movements of the joints. The lig~m~nts~ joint capsule, and connective tissue are largely comprised of collagen.
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 lig~m~nt~ or capsule. The two main forms of joint instability are called subluxations and dislocations. A subluxation occurswhen one surface of a joint slides out of position relative to the other surfacewhile ret~ining some contact belween the surfaces. A dislocation occurs when one surface of the joint completely di.~eng~ges and loses contact with the opposing surface. Generally, joints with a larger range of motion have more inherently loose soft tissue investments surrounding the joint and as a result are more prone to instability than others. For example, the shoulder (glen~humeral) joint has the greatest range of motion of all peripheral joints and has long been recognized as having the highest subln~tiQn and dislocation rate.
Instability ofthe shoulder can not only occur congen;l~lly and development~lly but also traumatically. Furthermore, this inq~bility often becomes recurrent and requires surgical repair. In fact, subluxations and dislocations are a common occurrence and cause for a large number of orthopedic procedures each year. Joints which require repair are characterized by symptoms which include pain, instability, weakness and limit~tion of function. If the in~t~hility is severe and recurrent, functional ine~raÇity and arthritis may result. Surgical all~"~)ls are directed toward ti~htt?ning soft tissue ~ es~ which have become loose. These procedures are typically perforrned CA 0226~981 1999-03-16 through open surgical approaches that often require hosrit~li7~tion and prolonged rehabilitation programs.
More recently, endoscopic (arthroscopic) techniques for achieving these same goals have been explored with variable success. FndoscQpic techniques have the advantage of being performed through smaller incisions and are usually less painful, performed on an outp~ti~.nt basis, are associated with less blood loss and lower risk of infection and have a more co~mPtic~lly ~cceptAble scar. Recovery is often faster postoperatively than using open technirlues.
However, it is often more technically d~m~n-~in~ to advance and tighten capsule or 1ig~ ou~ tissue arthroscopically because ofthe difficult access to pathologically loose tissue and because it is very hard to determine how much tightçning or advancement of the lax tissue is clinically necessary. In addition, fixation of advanced or tight~ned soft tissue is more difficult arthroscopicallythan through open surgical methods.
Collagen co~ g tissue is ubiquitous in the human body and provides the cohesiveness of the musculoskeletal system, the structural integrity of the viscera as well as the elasticity of inte~lment Collagen also demonstrates unique characteristics not found in other tissues. A previously recogrlized property of collagen is shrinkage of collagen fibers when elevated in temperature. Collagen fibrils are at their greatest length in the native state of a triple helix. Thermal energy to the collagen molecules disrupts the bonds which st~bi1i7~ the triple helix. The loss of the triple helix structure causes the fibrils to decrease in length or contract, giVillg the collagen co~ ing tissue the appearance of contracting. The degree of contraction is a function of both the height of temperature elevation as well as the length of te.lll)el alLlre elevation.
Thus, the same degree of contraction may be achieved by a high temperature elevation of short duration or by a lower temperature elevation for an extended duration.
Investigators have taken advantage of the unique collag~n features to effect positive ch~nges in non-vascularized collagen conlai~ .g structures. For ........ ..
CA 0226~981 1999-03-16 in.ct~nc~ the use of infrared laser energy to shrink collagen in the cornea of the eye relates to laser keratoplasty and has been described by Sand in U.S. Patent No. 4,976,709. Further, radio frequency (RF) electrical current has been used toreshape the cornea. Such shaping has been reported by Doss in U.S. Patents No.
4,326,529 and 4,381,007.
The capsule of the shoulder joint consists of a synovial lining and three well defined layers of collagen. The fibers of the inner and outer layers extendin 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 intermin~ling of collagen fibers ofthe three layers vary with di~lc;n~ portions ofthe capsule. The li~3~mçntouc components of the capsule are lep[esenled by abrupt thir~toning~ of the inner layer with a significant increase in well olgani~ed coarse collagen bundles in the coronal plane. 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 attçnu~ted and the capsule capacity increases secondary to capsule redlln~nre. In cases of conge~ AI or developmental multi-directional laxity, the ratio of type III to type I collagenfibers is often larger than usual. An appal~ s capable of shrinking the collagencontaining tissue in the shoulder may çlimin~te many of these instabilities.
Further, if this apparatus could be used endoscopically, many of the problems with current endoscopic techniques would be elimin~ted since fixation, tightçning and adv~nrçmrnt would no longer be lequ;led.
The use of endoscopic devices which simply heat the colla~lon c~ ing tissue are not s~ti~f~ctory because ofthe delivery of uncol,llulled energy. High telllpel~lures can cause cell necrosis and may damage the tissue.
There is a need for a method and apparatus which causes coll~gçn co..~ g tissues to contract while minimi7ing cell necrosis and damage to the tissue as well as other organs or bodies which may be present, more particularly, for joints and shoulder capsules. There is a need for a method and apparatus CA 0226~981 1999-03-16 WO 98/11944 PCTrUSg7/16120 capable of causing a collagen cont~ining tissue site at least partially a~ c~nt to a fluid media to contract a selected amount without d~ gh-g the tissue of the - site or any of the surrounding tissues or bodies whether they contain collagen or not.
SUMMARY OF T~E INVENTION
It is an object ofthe present invention to provide a method and appa,~lus configured to contract at least a portion of a selected site of a collagen cont~ining tissue.
Another object of the present invention is to provide a method and appa~L~Is configured to deliver sufficient energy to a s~lected site of a collagen co~ n;..g tissue to produce a contraction of at least a portion of the selected site.
Still another object of the present invention is to provide a method and appa,~lus configured to deliver sufficient energy to a selected site of a collagen co..~ -g tissue to effect an increase in the thermal energy content ofthe selected site.
Yet another object of the present invention is to provide a method and appa~ s configured to deliver sufficient energy to a s~.lected site of a collagen co..l~ g tissue to effect an increase in the telllpe~ re ofthe selected site to a pre-determined level.
A further object of the present invention is to provide a method and apphl~L~Is confi~l.red to deliver s~ffici~nt energy to a s~lected site of a collagen co.. ~ g tissue such that the te.lll)e~ re of the selected site increases to a pre-determined level and remains at or near that level for a selected period of time.
Yet a further object of the present invention is to provide a method and app~L~Is configured to deliver s-lfficient energy to a selected site of a cQll~g~n co..l~;l,ing tissue to create a contraction of collagen fibers.
CA 0226~981 1999-03-16 WO 98tll944 PCT/US97/16120 Still another object of the present invention is to provide a method and appa al-~S with a feedbac~ control device configured to deliver sufficient and controllable energy to a selected site of a collagen conl~ g tissue.
Another object of the present invention is to provide a method and apparatus with a feedback control device configured to deliver sufficient energyto a selected site of a collagen cont~ining tissue positioned at least partiallyadjac~nf to a fluid medium to contract at least a portion of the selected site and produce a therrnal feedbac~ signal representative of a composite of the therrnalenergy contents of at least a portion of the selected site and at least a portion of the adjacçnt fluid me~ m Another object of the present invention is to provide a method and apparatus with a feedbac~ control device configured to deliver suff1cient thermal energy to a selected site of a collagen co,~ ;ng tissue of an unstable joint at least partially positioned ~ c~nt to a fluid me~ m and at least partially repair the instability of the joint.
These and other objects of the invention are obtained with an apparatus for effecting change in at least a portion of a selected site of a collagen ch~ nil~g tissue that is a~ least partially adj~cent to a fluid merli--m The appa~ s inr.lud~c an energy delivery device confi~-red to deliver a level of energy to the selected site of the collagen containing tissue. The energy delivery device in~ludes a distal portion where a sensor is positioned. The sensor provides a signal indicative of the thermal energy content of at least the selected site ofthe collagen col.l~inil-~ tissue and the adjacent fluid m~i.-m to a feedback control unit. The signal is received by the feedb~cl~ control system which adjusts the level of energy supplied to the energy delivery device and delivered to the selected site based on the signal received from the sensor.
In another embodiment, the app~alus in~l~lrles an energy delivery device configured to produce a selected thermal distribution in the s~lected site of the collagen cont~ining tissue to effect a controllable contraction of at least a portion of the collagen fibers. The energy delivery device inrh1des a sensor CA 0226~981 1999-03-16 po~itioned at a distal portion of the energy delivery device. A ~edbncl~ controldevice is coupled to the sensor. A position of the sensor, a gen. ..el, y of thedistal portion of the energy delivery device and the feedbaclr control system provide a controllable energy delivery to the selected site of the collagen col-lAi~ -g tissue.
The energy delivery device is configured to deliver energy from the distal portion to the selected site ofthe collagen co..~ ;.,g tissue. The selected site absorbs at least a portion of the delivered energy and the thermal energy content and temperature of the sçlected site are increased. As the thermal energy content ofthe selected site is increased, thermal energy is con~ cted to the collagen fibers of the s~ected site. Collagen fibers exposed to s..ffil~.içnt thermal energy at least partially lose their triple helix shape and contract. Thus, the delivery of energy to the selected site causes the tel,lpe~ re and the thermal energy content of the sçlected site to hl.;l~ase and create a contraction of at least a portion ofthe collagen co.,~ g tissue site.
In one embodiment, the sensor is located within the distal portion.
During surgery, the distal portion is preferably placed in contact with a portion of the selected site and the fluid medillm adjacçnt to the selected site. Because of this contact, the thermal energy from the selected site and the adjacçnt fluid medium will conduct through the thermally conductive sections of the distal portion to the sensor. The m~gnitu(le of the resulting signal lepresellLs a composite of the thermal energy contents of the selected site and the adjacent fluid medi~lm The sensor provides a signal which is le~ se.l~ e ofthe thermal energy contents of a portion of the fluid metiil~m a~ljacçnt to the selected site as well as at least a portion of the selected site. As a surgeon moves the distal portion about a selected area, it is possible for a surgeon to bring the distal portion into contact with a selected site which has previously been elevated to - the desired temperature for the desired period of time. This second application of energy may quickly elevate the temperature enough to cause cell necrosis or CA 0226~981 1999-03-16 cause the temperature at the sPIected site to remain elevated for longer than the desired period required for the desired level of collagen contraction.
Since the mAgnih1de of the signal provided by the sensor partially l epl esellls the thermal energy of the fluid me~ m the apparatus is responsive to changes in the thermal energy content of the fluid medi~Im Due to the nature of delivering energy to a selected site thermal energy is more disperse in the fluid medium. Because the apparatus responds to thermal energy in the fluid metlillm the appal~l~s reduces cell necrosis resulting from sl~ccescive applications of energy to the selected site. Stray contractions are contraction which occur away from the selected site due to the fluid metlillm becoming elevated in temperature for an PYtçnded period of time. Further response of the apparallls to therrnal energy in the fluid mP~ m can also reduce stray contractions.
DESCRIPTION OF T~IE DRAWINGS
Figure 1 is a perspective plan view of an embodiment of the present invention illustrating an appa~aLus for contracting collagen con~ g tissue.
Figure 2 is a pel ~pe~ re plan view of an embodiment of the present invention illustrating an appa~ ~LIls coupled to an energy source for contracting collagen co.~ ;.,g tissue.
Figure 3 is a perspective plan view of an embodiment of the present invention illustrating an appa~lus for contracting collagen coI~Ail.;..g tissue a desired amount in contact with a collagen co~ e tissue.
Figure 4 is a perspective plan view of an embodiment of the present invention illusll~ling an appal~ s for contracting coIIAgPn co~ ni~ tissue a desired amount delivering heat to a selected site within a setected area.
CA 0226~981 1999-03-16 W O 98111944 PCTrUS97/16120 Figure 5 illustrates the po~itioning of a distal end of an energy delivery device while delivering energy to a selected tissue site and a portion of an ~-ljacent fluid medium and the measurement of a composite telllyel alul e.
Figure 6 is a cross-sectional view of a distal portion of the energy delivery device with a sensor positioned in interior of the distal portion.
Figure 7 is a pe- ~ye~ e plan view of an embodiment of the present invention illustrating an apparatus for contracting collagen CO"~ g tissue a desired amount where the energy delivery surface is a composite construction.
Figure 8 is a sc.h~m~tic of an embodiment of the present invention illustrating a feedbarlr control system.
Figures 9(a)-(d) are perspective plan views of di~relenl embodiments of the present invention illustrating several apparatus, each configured to provide a signal from a sensor such that the signal I eplese..ls thermal energies of di~(~-"
surfaces or me~ -m~.
Figure 10 is a perspective plan view of an embodiment of the present invention illustrating an apparatus with a handpiece, energy delivery device andan operating cannula according to the present invention.
Figure 11 is a perspective plan view of an embodiment of the present illustrating an invention apparatus inrlu~ing an in~ ting layer for preventing damage to surrounding tissues, organs or bodies.
Figure 12 is a perspective plan view of an embodiment of the present invention illustrating an apparatus inrlu-ling a handpiece, an energy delivery CA 0226~981 1999-03-16 W O98111944 PCTrUSg7/16120 device and a sleeve that slides across the surface of the energy delivery deviceto vary the amount of energy delivery device conductive surface.
Figure 13 is a perspective plan view of an embodiment of the present invention illustrating an apparatus inrhl~in~ a thermal in.~l~]~ting layer whichcan be positioned to specify the surface of the distal end section from which the sensor is able to detect thermal energy.
Figure 14 is a sectional view of an embodiment of the present invention illustrating a deflected energy delivery device with a resistive heating elementpositioned in an interior lumen of the energy delivery device.
Figure 15 is a perspective plan view of an embodiment of the present invention illustrating an energy delivery device with a steering wire positionedon the exterior of the energy delivery device.
Figure 16 is a sectional view of an embodiment of the present invention illustrating an energy delivery device with a lumen and a plug that is ~tt~ched to the energy delivery device distal end.
Figure 17 is a sectional view of an embodiment of the present invention illustrating an energy delivery device with an oval cross section and a heating zone in the tissue.
Figure 18 is a sectional view of an embodiment of the present invention illustrating a handle, energy delivery device, ope~ g cannula and a viewing scope, with the viewing scope and energy delivery device po.cition~d in the opel~Lingc~nm~l~
CA 0226~981 1999-03-16 Figure 19 is a cross sectional view of an embodiment of the present invention illustrating a device of Figure 18, taken along the lines 19- 19.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to Figure 1, an apparatus for contracting collagen co.,~ g tissue to a desired level is generally denoted as 10. Apparatus 10 incllldes a handpiece 12 that is preferably made of a thermal in.c~ tin~ material, or an electrode that is electrically inc~ ted Types of such inc~ tin~ materials are well known to those skilled in the art. An energy delivery device 14 is coupled to handle 12 at a proximal end 16 of energy delivery device 14, and may be att~ched thereto. A distal end 18 of energy delivery device 14 in~ des a distal portion 20 which may have a geometry that delivers a controlled amount of energy to tissues in order to achieve a desired level of contraction of collagen fibers in a coilagen cont~ining tissue. Located at distal portion 20 is one or more sensors 22 which provide a signal whose m~nit~lde is leplesel.lalh~e of the amount of thermal energy sensed.
As shown in Figure 2, energy is supplied from an energy source 24 through a cable 26 to energy delivery device 14. Since several types of energy can cause an elevation in the temperature of a collagen cnnt~ining tissues 28.
Energy source 24 can include but is not limited to RF, microwave, ultrasonic, coherent and incoherent light, thermal transfer, and reCict~nce heating.
As illustrated in Figure 3, distal portion 20 is configured to be positioned ~dj~c~nt to a collagen co~ i..;.lg tissue 28 which is at least partially ~djacçnt to a fiuid mP~ m 30. Appropriate collagen co.,l~;nil~g tissues 28 can include but are not limited to vascularized densely collagenous structures such as ten~lonc~lig~mentc, joints capsules and the like. Distal portion 20 is pler~l~ly in contact with collagen cont~ining tissue 28. Fluid medium (gas, liquid, or a combination) 30 may be flowing as would result from irrigating collagen co~ sg tissue 28 or it may be substantially less dynamic or non-moving.
CA 0226~981 1999-03-16 Further, fluid medillm 30 need only be partially fluid and contain bone, portions of organs or other bodies and the like.
Referring now to Figure 4, energy delivery device 14 is configured to deliver energy from distal portion 20 to a selected site 32 ofthe cQll~gen co.. ~ g tissue 28. Selected site 32 receives at least a portion of the delivered energy. Once the energy is delivered it becomes thermal energy causing the thermal energy content and the te~l,?elalLIre of selected site 32 to increase. As the thermal energy content of selected site 32 is increased, thermal energy is con~ucted to the collagen fibers in and around selected site 32. Collagen fibersexposed to sufficient thermal energy loose their triple helix shape. Since the triple helix shape of collagen fibers is the longest shape for collagen fibers, fibers which loose their triple helix shape will contract. Thus, the delivery ofenergy to selected site 32 causes the te,l.pe~ re and the thermal energy contentof selected site 32 to increase and effects collagen fibre contractions. The collagen fiber contraction results in a contraction of collagen co~ il-il-g tissue 28.
Energy delivery device 14 is configured to deliver a level of energy to selected site 32. Sensor 22 provides a signal indicative of a composite te"")e~ re of at least selected site 32 and at least a portion of at least a portion of a(lj~cent fluid me~ m 30 to a feedback controi unit. The signal is received by a feedbac~ control system which adjusts the level of energy supplied to energy delivery device 14 and delivered to selected site 32 based on the signal received from sensor 22.
Throughout the l~eal,.,e,ll, it is often be desirable to effect contractions in a selected area 34 which is larger than a selected site 32. Further, may be desirable to elevate the te-..?e~ re of the selected site 32 or selected area 34 to a desired average temperature for a specified period of time. There are several methods available for achieving these results. For in.ct~nce, one embodiment is to "paint" distal portion 20 across selected area 34 by continually moving distal portion 20 over the surface of the selected area 34 so that the entire selected area CA 0226~981 1999-03-16 W O 98/11944 PCTrUS97tl6120 34 is covered. Selected area 34 can then be brought to the desired temperature and l~ah~ed at that tenlpe.~L~lre by continually moving distal portion 20 over s~lected area 34. In another embodiment, distal portion 20 is left at selected site 32 until the desired temperature is obtained for the desired time. Distal portion 20 is then moved to another selected site 32 for a desired time. This pattern isrepeated until the entire selected area 34 is covered. A colllbina~ion of these techniques may also be used.
Referring now to Figure 5, the composite tell.pe.~ e is a co.l,~.in~;on of at least two diLrerenl temperatures in some ratio. One tempe.~ re 25 is from at least a portion of ~Ajac~nt fluid me~ m 30 and another te.. -l)el~lure 27 of at least a portion of selected tissue site 32. This ratio is a function of different parameters incluAing but not limited to the size, shape, dimensions and geometry of a thermal energy delivery surface of energy delivery device 14, the portion of the thermal energy delivery surface that is in contact with ~Aj~cent fluid medium 30 and selected tissue site 32, the location of sensor 22 in relationship to the thermal energy delivery surface. Current flow 29 which creates molecular friction, and conducted thermal energy are greater in selectedtissue site 32 than in adjacent fluid me~ m 30 due to the higher recist~nce of the tissue.
One embodiment of distal portion 20 is illustrated in Figure 6. Distal portion 20 of energy delivery 14 in~llldes sensor 22 positioned in an interior of distal portion 20. A thermally conductive material 31 at least partially surrounds sensor 22 and a potting compound 33 is in~lndeA Distal end 18 is made of stainless steel, and a nylon coating is po~itioned at an exterior surface of distal portion 20.
At the thermal energy delivery device fluid me~illm interface there is less resistance and a hydro dynarnic force which contribute to a lower reflectedtemperature. At the tissue interface there is a static conductive sit~tion with a higher re~ ance producing higher reflective temperature at the interface.
CA 0226~981 1999-03-16 W O 98/11944 PCTnUS97116120 Energy delivery device 14 can be made of a number of di~erelll materials including but not limited to stainless steel, pl~tim~m, other noble metals and the like. Energy delivery device 14 can be made of a memory metal, such as nickel tit~nillm, cornmercially available from Raychem Corporation, Menlo Park, California. Energy delivery device 14 can also be a composite construction whereby di~lent sections are constructed from di~lellL materials.
Further, it may be desirable for delivery device 14 to be a composite of a firstmaterial 36 which is not conductive to the type of energy being delivered and a second material 38 which is conductive to the type of energy being delivered as shown in Figure 7. Such a construction permits treatment in locations where there are tissues, organs or other bodies present which the surgeon does not wish to expose to the delivered energy. For example, when energy delivery device 14 is introduced into a joint where it is desirable to treat a specific section of the joint and avoid delivery of energy outside of that section, an energy delivery device 14 partially constructed of non-con-~usting material 36 can permit tre~tm~nt One embodiment of an open or closed loop fee~ba~l~ control system 40 is shown in Figure 8. The physician can, if desired, override the closed or openloop feedback control system 40. The fee(lb~c~ control system 40in~hldes an energy source 24, (in~hl(ling but not limited to a RF source), a temperature measuring device 44, a voltage and current measuring device 46, a user display unit 48, a timekeeping device 50, a microprocessor 52 and a user input device 54.
Energy source 24 supplies energy to energy delivery device 14 for delivery to selected site 32. The voltage and current supplied to the energy delivery device 14 are measured on voltage and current measuring device 46 and can display these to the user on user display unit 48. Tell,pelaLu~e measuring device 44 measures the te..~pe~ re at sensor 22, in~lutling the telllpel ~lure of adjacent fluid medium 30 and selected tissue site 32. The CA 0226~981 1999-03-16 tel.lpel~L-Ire measured by temperature measuring device 44 can be displayed to the user on the user display unit 48.
In one embodiment a signal produced by the sensor 22iS received by a feedb~ control system 40. Feedbaçk control system 40 monitors the signal produced by sensor 22 and adjusts the amount of energy or current supplied to energy delivery device 14 according to the m~gnihlde ofthe signal. Energy is supplied to apparatus 10 at a particular rate. The rate of energy delivery can be expressed as power. Power supplied to energy delivery device 14 is adjusted so the temperature at sensor 22iS elevated to a temperature which is desired by theuser and is input to the fee~iba~L control system 40. Once the desired telllpel ~ure is reached, power is adjusted so that the temperature at sensor 22has minor fluctuations but averages to the desired telllpcl ~L~Ire over time. Thus, the feedbac~ control system 40 m~int~in~ the desired tel.lpel~ re at the sensor 22 and correspondingly at the selected site 32.
In another embodiment, feedb~ck control system 40 also monitors time.
In this embodiment both time and temperature are inputs. Thus, once the temperature at sensor 22iS elevated to the desired tel~lpel~ure, fee(lbacl~ control system 40 tracks the length of time sensor 22 averages the desired temperature.
Once the temperature at sensor 22 averages the desired temperature for the desired time, fee~bac~ control system 40 may either stop the delivery of energy or it may inform the user on a user display screen (not shown). Thus, feedback control system 40 can be used to m~int~in the desired temperature at selected site 32 for the desired time.
In one embodiment, microprocessor 52 monitors voltage, current and temperature. Microprocessor 52 car, calculate the power supplied to energy delivery device 14 from the current and voltage and can display the power on the user display unit 48. Microprocessor 52 can also monitor and control a tim~keeping device 50. The microprocessor 52 can signal time~eeping device 50 to begin or stop tracking time. While timekeeping device 50 is tracking time and microprocessor 52 can monitor the passage of time. Microprocessor 52 also CA 0226~981 1999-03-16 receives input from a user input device 54. User input device 54 allows a user to program rnicroprocessor 52 or input information such as the desired temperature or the desired time.
Energy source 24 includes circuitry for mod~ tinp: the power supplied to the energy delivery device 14 according to a signal received from microprocessor 52, thus, microprocessor 52 can control the power supplied to the energy delivery device 14. Microprocessor 52 is programrned to ad~ust the power supplied to energy delivery device 14 so that the tenlpel~ re at sensor 22is ."~ ;"ed at the desired telllpelal~lre for the desired time. The program takes into account at least the desired time, temperature and desired tell~ re in making these adjustments.
Feedback control system 40 is used to obtain the desired degree of contraction by ~ t~ i"g selected site 32, at a desired temperature for a desired time. It has been shown that temperatures of 45 to 90 degrees C can cause collagen fibers contractions. It has also been shown that the degree of collagen fiber contraction is controlled by how long the temperature is elevatedas well as how high it is elevated. Thus, the same degree of contraction can be obtained by exposing selected site 32 to a high temperature for a short period of time or by exposing selected site 32 to a lower t~lllpe-~ re for a longer periodof time. A ~l erel ~ ed range for desired te~npe~ res is about 45 to 75 degrees C, still a more pl~rel~ed range is 45 to 65 degrees C. Before tre~tm~nt the surgeonevaluates the characteristics of the selected site 32 to determine what degree of contraction is necessary and also whether it is app.opl;ate to treat the selected site 32 with a high telllpe~ re for a low period oftime or lower te...pe.~ re for a long period of time. The surgeon then enters into the user input device 54 thedesired te ..pe- ~lure and the desire time. Feedbar.~ control system 40 uses this information to control the delivery of energy to selected site 32 which results in a controlled contraction of collagen colll~ining tissue fibers. The controlled collagen fiber contraction allows for a desired degree of collagen co..~ g tissue contraction.
CA 0226~981 1999-03-16 Additionally, fee~bar.~ control system 40 can be used to effect how deeply within the collagen cont~ining tissue 28 the collagen fiber contractions occur. For instance, elevating the tel.lpe~ re of selected site 32 to the low end of the range effects contractions near the surface of collagen cont~ining tissue28. Elevating the temperature to the high end of the range effects contractions deeper within collagen co.~ g tissue 28. Thus, if the surgeon is dealing with a very thin collagen cont~ining tissue 28 which is adjilcent to tissue which maybe damaged by elevated temperatures, the surgeon may choose to elevate the temperature of selected area 34 to a low temperature for longer periods of time.However, if collagen cont~ining tissue 28 is thicker, the surgeon may choose higher temperatures to effect contractions deeper in collagen cont~ining tissue 28. Thus, the choice of the desired temperature can control the thermal energy distribution and thus the depth of contractions.
Feedback control system 40 further allows apparatus 10 to minimi7e and even prevent cell necrosis (ablation) resulting from exposure to high temperatures. High temperatures can cause excessive destruction and ~icintegration of the collagen fibrillar patterns and cell necrosis. Since feedback control system 40 can m~iht~in the temperature of sensor 22 at a desired temperature, the temperature at selected site 32 does not exceed ablation temperature.
Further, feedback control system 40 can prevent overshoots which may cause cell necrosis. Overshoots occur while raising the te...pe~ re of selected site 32 or selected area 34 to the desired level and temporarily surpassing thatlevel. Some overshoot of the desired te...~)e.~L~Ire will be inherent in most embodiments of feedback control systems, however, it is possible to cause cell necrosis or dissociation if the overshoot is high enough or of long enough duration. Feedb~cl~ control system 40 reduces overshoots by reducing the rate of energy delivery once the selected site 32 te--.l)el~ re is near the desired level.
Thus, when energy is first delivered to a selected site 32, there can be a high rate of energy delivery, however, once the temperature of the selected site is nearing W O 98/11944 PCTrUS97/16120 the desired range, the rzte of energy delivery is reduced ir order to prevent anovershoot. Pro~ g this rampiag down effect,lito a feedbac~ control system 40 is well known to those in the art of feedbac!c control. Note: Some overshoots are ok, but the average ternp rnust fall within a non-dilative range.Sensor 22 can consist of, but is not lir.~ted to, a therrnocouple, a thermistor or phosphor coated optical fibers. The se1lror 22 can be in an interior of the distal portion 20 or on the surface of the distal portion 20 and can further be a single sensor 22 or several sens~rs. It can als~ be a band or patch insteadof a sensor 22 which senses or,ly discrete points.
Sensor 22 provides 2 sigr.al whose m~g~litude is representative ofthe thermal energy content of the surfaces &nd mediums in physical contact Wit}l thesurface of the sensor 22. Thus, if several surfaces or mediumc are in physical contact with sensor 22, the m~gnitllde of the signal provided by sensor 22 will be representative of a composite of the thermal energy contents of those surfaces and/or mediums. Further, the effective suriace of sensor 22 can be increased by wholly enclo~ing sensor 22 ir. a medillm which easily conducts therrnal energy. In this embodiment, thermal energy will be conducted firom the surface of the thermally conductive mediuln to th ser,sor 22. The magnitude of the signal will represent a com?csite OI fl~e ther~r~l energy contents of anysurfaces and mediums in physical co~act with the surface of the thermally conductive medium. For inct~nce~ Figure 9~a) il'ustrates an embodiment where sensor 22 is located within distal portion 20. Fu.rther, distal portion 20 is inphysical contact with a portion Gf the selec.e~ site 32 and fluid medillm 30 atljacPnt to the selected site 32. r'ec~ r~e cf this cor.tact, the thermal energy from selected site 32 and adjacent fluid rr.ediurn.30 cond.lcts through the thermally conductive sections cf dirtal ~" crt.~n 23 t~ sensor 22. The m~,~nitude of the resulting signal provide& by senrcr 22 represen~s the com~osite thermal energy content of selected site 32 and at leas~ a ~~ortic;l of ~ ctont fluid meditlm 30.
CA 0226~981 1999-03-16 By strategically positioning and configuring sensor 22, it is possible to design the distal portion 20 such that signal represents the thermal energy content of specific surfaces or medillm.c. For in~t~nce, Figure 9(b) illustrates an embodiment where the sensor 22 is positioned such that the thermal energy S con~llcted to the sensor is from substantially only sPIected site 32. Thus, sensor 22 provides signal which is l ep~ ese"l~Live of the therrnal energy content of substantially only selected site 32. Further, Figure 9(c) shows an embodiment where sensor 22 is configured as a band and positioned such that the thermal energy conducted to sensor is from substantially only fluid medil]m 30 ~1jaeçnt to selected site 32. Thus, sensor 22 provides a signal which ep, ese"ls substantially only the therrnal energy content of the ~dj~cçnt fluid me-lium Figure 9(d) illustrates another embodiment where fluid medillm adjacent to selected site 32 contains other tissue, organs or bodies 56. In thisembodiment, the signal provided by sensor 22 le~ s~nls a composite ofthe thermal energy contents of selected site 32 and ~dj~ nt fluid medillm 30 as well as the other tissues, organs or bodies 56.
Sensor 22 provides the composite signal of thermal energy and temperature whether fluid merlillm 30 is flowing or non-flowing. When the surgeon chooses to deliver energy to selected area 34 by moving distal portion 20 from selected site 32 to another, it is possible to bring distal portion 20 into physical contact with a selected site 32 which has previously been elevated to the desired temperature for the desired period of time. This second application of energy may quickly elevate the tenli)e,~u~e enough to cause cell necrosis or may cause the temperature at selected site 32 to remain elevated forlonger than the desired period causing the collagen fibers to contract more thandesired.
Positioning sensor 22 to provide a signal which represel,L~ a composite of the therrnal energy contents of selected site 32 as well as ~dj~cPnt fluid medillm 30 reduces cell necrosis or over contraction caused by a second application of energy. As energy delivery device 14 delivers energy to selected .
CA 0226~981 1999-03-16 site 32 it also delivers energy to fluid meriillm 30 which is in physical contact with energy delivery device 14 adjaG~nt to selected site 32. This delivery of energy to fluid medium 30 causes the thermal energy content of fluid medium 30 to increase. The thermal energy content of fluid me~illm 30 ~dj~cent to S selected site 32 also rises due to conduction of thermal energy from se}ected site 32 to fluid tne~ m 30. Furthermore, due to convection resulting from the movement of distal portion 20, thermal energy disperses through fluid m~ium 30 at a quicker rate than through collagen co..~ g tissue 28.
As a result ofthe energy ~lanar~la described above, the colleal)ol1dillg elevations in temperature will be more dispersive in fluid me~ m 30 than in selected site 32. Thus, the signal produced by sensor 22 is di~rent when dis~:alportion 20 is placed a(ljacçnt to a previously heated selected site 32 than whendistal portion 20 is placed in a selected site 32 away from any previously heated selected sites 32. Although the selected sites 32 in the former and latter caseswill have similar thermal energies, in the former case, the dispersive energy influid medium 30 causes the fluid medium 30 to have a higher thermal energy content than in the latter case. Since sensor 22 provides a signal whose m~gnit~lde ~eplesen~s a composite ofthermal energies of fluid medi~lm 30 ~djacent to selected site 32, in the former case sensor 22 provides a signal to feedback control system 40 indicating an elevated thermal energy content and reduces the amount of energy delivered to selected site 32. This reduced energy delivery decreases cell necrosis or o~lco"l,action near selected site 32. The same is true in those in~t~nres when distal portion 20 is again passed over a previously heated selected site 32.
It will also be applec;aled that when sensor 22 is positioned where it provides a signal representing a composite in~lu~ing adjacent fluid me~illm 30 when the surgeon chooses to paint s~lected area 34 rather than moving from one selected site 32 to another. The surgeon will want to keep the te~ ei~ure of an entire selected area 34 within a specific range during the pau,~h~g process. As distal portion 20 is painted across s~lected area 34 it leaves a path which has CA 0226~981 1999-03-16 W O 98/11944 PCT~US97116120 been heated and may intersect that path several times during the process of keeping the temperature within the desired range. As selected area 34 is covered and distal portion 20 intersects the heated path it is desirable to deliver more energy to areas which are not in the path and consequently have not been previously heated. It is also desirable to deliver less energy to areas which are part of the path and have previously been heated. By delivering energy this way, the thermal energy content of the selected area 34 will approach a uniform thermal energy across the selected area.
As described above, thermal energy can be more dispersive in fluid medillm 30. As a result, when distal portion 20 is moved toward a previously heated path sensor 22 provides a di~erenl signal than it would if it were not traveling toward a previously heated path. Fluid mçdillm 30 will have a higher thermal energy content in the forrner case than in the latter case. Since sensor22 provides a signal whose m~nitllde is related to a composite of the thermal energies of fluid m~dillm 30 adjacent to selected site 32 and the selected tissue site 32 in the forrner case sensor 22 provides a signal to feedbar.~ control system 40 indicating an elevated thermal energy content and reduces the amount of energy delivered to selected site 32. As a result ofthe elevated therrnal energycontent, feedback control system 40 reduces the amount of energy delivered in the former case. The result allows the te,.l~e,al~lre across the selected area 34 to approach uniro~ ily. U~iiro",li~y of temperature is desirable as it reduces cellnecrosis or overcontractions near path intersections.
Positioning sensor 22 such that it provides a signal which I epl t;senls a composite ofthermal energies inr~ ing adjac~nt fluid mç~lium 30 can also reduce stray contractions. Stray contractions are undesired contractions of collagen fibers outside selected area 34. As described above, while energy is delivered to selected area 34, the thermal energy content of fluid mç(lium 30 also increases. During an extended 1l ~llllenl it is possible for the thermal energy content of fluid medium 30 to rise considerably. If the thermal energy content of fluid mç~lillm 30 remains elevated for an extended period oftime it is CA 0226~981 1999-03-16 possible for the conduction of thermal energy from fluid me~ m 30 to collagen co.~ .g tissue 28 to elevate the te~ )e.~ re of collagen coi~Ai.~ing tissue 28 sufficiently to cause undesired contractions of collagen fibers and may occur outside sele~cted area 34. These stray contractions are even more of a problem when the fluid mer~il-m 30 is flowing since the flow will carry the heated fluidmedium 30 away from the selected area.
These stray contractions are reduced by positioning sensor 22 to provide a composite signal which inr.l~ldes at least a portion of fluid medil-m adj~cPnt to the selected site 32. For inct~nçe, when the thermal energy content of fluid me~ m 30 is raised, the signal will be di~renl than when it is not and the energy delivery is adjusted accordingly. Since sensor 22 provides a signal whose m~gnit~lde is related to a composite which inr.l~ldes the fluid medium 30 adjac~nt to the sPIected site 32, in the forrner case sensor provides a signal to feedb~cl~ control system 40 indicating an elevated thermal energy content and reduces the amount of energy delivered to s~lected site 32. The reduced energy delivery reduces the amount of energy delivered to fluid medium 30 and concçquçntly reduce stray contractions.
Apparatus 10, comprising handpiece 12 and energy delivery device 14, is adapted to be introduced through an operating cannula 58 for percutaneous applications. It will be appreciated that apparatus 10 may be used in non-percutaneous applications and that an operating cannula 58 is not n~cecc~ly in the broad application of the invention.
As illustrated in Figure 10, appar~ s 10 can also include, as an integral member, an operating cannula 58 which can be in the form of a hypodermic trocar with tlim~ncions of about 3 to 6 mm outside ~ m~o,ter, with tubular geometries such as those of standard col-.lllel.;ially available ope.~ling ç~nm~l~c Operating cannula 58 can be made of a variety of biocompatible materials innl~lding but not limited to stainless steel, and the like.
Ope-~Ling cannula 58 has a cannula p.o~umal end that att~hes to handpiece 12 and a cannula distal end 60 which can have a sharp or piercing end CA 0226~981 1999-03-16 W O 98/11944 PCT~US97/16120 for penetrating body structures in order to introduce energy delivery device 14 to a selected site 32. Energy delivery device 14 is positioned within an interior lumen of operating cannula 58 and is extendable beyond cannula distal end 60 in order to reach selected site 32. Energy delivery device 14 can be advanced and retracted in and out of operating cannula 58 by activating a deployment button 62 which is located on the exterior of handle 12. Deployment button 62 is p~ere~al)ly activated by the operator merely by sliding it, which causes energy delivery device 14 to advance in a direction away from cannula distal end 60.
Deployment button 62 can be pulled back, causing a retraction of energy delivery device 14 towards cannula distal end 60. In many in~t~ncçc, energy delivery device 14 is retracted to be positioned entirely within operating cannula 14. Energy delivery device 14 can also be deployed with fluid hydraulics, pne~-m~tics, servo motors, linear actuators, and the like.
In Figure 11, distal portion 20 of energy delivery device 14 incl~ldes an ing~ ting layer 64 which is substantially impenetrable to the energy delivered to collagen co~ h~ g tissue 28. Specifically, in the case of an RF energy source 24, electrical insulation can be used. Insulation 64 can be formed on energy delivery device 14 such that a miniml~m of energy is delivered to tissue,organs or other bodies which the surgeon does not wish to treat. For example, when energy delivery device 14 is introduced into a tight area, and only one surface of the tight area is to be treated, then it is desirable to avoid delivering energy outside of that surface. The inclusion of in.c~ ting layer 64 accomrli.~hes this result. Suitable insulation materials include but are not limited to polyamide, epoxy varnish, PVC and the like.
The area of energy delivery device 14 that serves as a conductive surface 66 can be ~ju~ted by the inclusion of an in~ ting sleeve 68 (Figure 12) that is positioned around energy delivery device 14. Sleeve 68 may be advanced and retracted along the surface of energy delivery device 14 in order to increase ordecrease the surface area of conductive surface 44 that is directed to collagen cont~ining tissue 28. Sleeve 68 can be made of a variety of materials inr.ll~(ling _ _ . . . . . .
CA 0226~981 1999-03-16 W O 98/11944 PCTrUS97/16120 but not limited to nylon, polyamides, 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 68, inclu~ing but not limited to printed circuitry with multiple circuits that can be individually activated, and the like.
As illustrated in Figure 13, distal portion 20 of energy delivery device 14 incll-des a thermally ine~ ting layer 70 which is subst~nti~lly impenetrable to thermal energy. Thus, thermal inc~ ting layer 70 can be used to limit the arnount of selected site 32 that contributes to the te~llpe.~lule detected by sensor ~2. For example, by in~ ting only distal end 18 of distal portion 20 substantially only thermal energy from fluid medi~m 30 ~dj~c~nt to selected site 32 is con~llcted to sensor 22. Thus, the m~gnitl-de ofthe signal produced by the sensor 22 represents substantially only the thermal energy content of fluid medium 30 adj~c.çnt to selected site 32. Thermal energy in~ ting layer 70 can also be used in conjunction with a delivered energy jn~ ting layer 64 to cover identical areas or different areas. Thermal in~ul~ting layer 70 can be constructed of the same material as the delivered energy in.~ tinE layer 64.
For many applications, it is necec~ry to have distal portion 20 become deflected. In Figure 14, a resistive heating element 72 can be positioned in an interior lumen of energy delivery device 14 which is at least partially made of memory metal. Resistive heating element 72 can be made of a suitable metal that transfers heat to energy delivery device 14, causing distal portion 20 to become deflected when the temperature of energy delivery device 14 reaches a level that the memory metal is caused to deflect, as is well known in the art.
Not all of energy delivery device 14 need be made of the memory metal. It is possible that only distal portion 20 be made of the memory metal in order to effect the desired deflection. When deflection is caused by heating memory metal, it is desirable to insulate sensor 22 from the effects of the resistive heating element 22. One method of doing this is demonstrated in Figure 12 CA 0226~981 1999-03-16 W O 98/11944 PCT~US97/16120 where thermal inc~ tin~ layer 70 is located between the distal portion 20 and sensor 22 where sensor 22is a band.
Deflection can also be accomplished meçh~ni~ lly A steering wire, or other mech~nic~l structure, is att~çhed to either the exterior or interior of energy delivery device 14. A deflection button 74, located on handle 12 (Figure 10), isactivated by the physician, causing a steering wire 76 (Figure 15) to tighten, and impart an retraction of energy delivery device 14, resulting in a deflection of distal portion 20. It will be app-eciated that other mech~nical mec.l~ ,.,g can be used in place of steering wire 76. The deflection may be desirable for selected sites 32 that have difficult access, and it is nec~cs~,y to move about a non-planar collagen conl~;..it-g tissue 28. By deflecting distal portion 20, theopportunity to provide more even thermal energy to se~ected site 32 is achieved,and the possibility of ablating or dissociation of collagen material is greatly reduced.
As shown in Figure 15, steering wire 76 att~hes to a flat formed on the exterior of energy delivery device 14. Wire EDM technology can be used to form the flat on energy delivery device 14. A "T" bar configuration is illustrated in Figure 15. Chemical etching may be used to create the T bar.
Steering wire 76 need not be an actual wire. It can also be a high tensile strength cord such as Kevlar. Steering wire 76 can be made of stainless steel flat wire, sheet material, and the like.
As shown in Figure 16 energy delivery device 14 can be tubular in nature with a central lumen. Distal portion 20 can include a conductive plug 78 that is sealed to distal portion 20 by welding, e-beam, laser and the like.
CONTRACTION OF SO~Y TISSUE
CROSS-REFERENCE TO RELATl~D APPLICATIONS
BACKGROUND OF THE INVENTION
Related Inventions This application is a continuation in part of Serial No. 08/637,095, filed April 24, 1996, entitled METHOD AND APPARATUS FO~ CONTROLLED
CONTRACTION OF SOFT TISSUE, which is a continuation of Serial No.
08/389,924, filed February 16, 1995, entitled METHOD AND APPARATUS
FOR CONTROLLED CONTRACTION OF SOFT TISSUE, which is a continuation of Serial No. 08/238,862, filed May 6, 1994, entitled METHOD
AND APPARATUS FOR CONTROLLED CONTRACTION OF SOFT
TISSUE.
Field ofthe Invention This invention relates generally to a method and apparatus for delivering thermal energy to a selected collagen cont~ining tissue and effecting a contraction of at least a portion of the collagen cont~ining tissue, and more particularly to a method and apparatus for contracting a collagen co~ ;"g tissue that is at least partially adj~c~nt to a fluid medium.
Description of the Related Art Instability of peripheral joints has long been recognized as a ~ignifir.~nt cause of disability and functional limitation in patients who are active in their daily activities, work or sports. Diarthrodial joints of the musculoskeletal system have varying degrees of intrinsic stability based on joint geometry and lig~m~nt and soft tissue investment Diarthrodial joints are comprised of the . .
CA 0226~981 1999-03-16 articulation of the ends of bones and their covering of hyaline cartilage surrounded by a soft tissue joint capsule that In~ the constant contact of the cartilage surfaces. This joint capsule also Ill~ c within the joint the synovial fluid that provides nutrition and lubrication of the joint surfaces.
~ .ig~ e~ s are soft tissue con-len~tions in or around the joint capsule that reinforce and hold the joint together while also controlling and restricting various movements of the joints. The lig~m~nts~ joint capsule, and connective tissue are largely comprised of collagen.
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 lig~m~nt~ or capsule. The two main forms of joint instability are called subluxations and dislocations. A subluxation occurswhen one surface of a joint slides out of position relative to the other surfacewhile ret~ining some contact belween the surfaces. A dislocation occurs when one surface of the joint completely di.~eng~ges and loses contact with the opposing surface. Generally, joints with a larger range of motion have more inherently loose soft tissue investments surrounding the joint and as a result are more prone to instability than others. For example, the shoulder (glen~humeral) joint has the greatest range of motion of all peripheral joints and has long been recognized as having the highest subln~tiQn and dislocation rate.
Instability ofthe shoulder can not only occur congen;l~lly and development~lly but also traumatically. Furthermore, this inq~bility often becomes recurrent and requires surgical repair. In fact, subluxations and dislocations are a common occurrence and cause for a large number of orthopedic procedures each year. Joints which require repair are characterized by symptoms which include pain, instability, weakness and limit~tion of function. If the in~t~hility is severe and recurrent, functional ine~raÇity and arthritis may result. Surgical all~"~)ls are directed toward ti~htt?ning soft tissue ~ es~ which have become loose. These procedures are typically perforrned CA 0226~981 1999-03-16 through open surgical approaches that often require hosrit~li7~tion and prolonged rehabilitation programs.
More recently, endoscopic (arthroscopic) techniques for achieving these same goals have been explored with variable success. FndoscQpic techniques have the advantage of being performed through smaller incisions and are usually less painful, performed on an outp~ti~.nt basis, are associated with less blood loss and lower risk of infection and have a more co~mPtic~lly ~cceptAble scar. Recovery is often faster postoperatively than using open technirlues.
However, it is often more technically d~m~n-~in~ to advance and tighten capsule or 1ig~ ou~ tissue arthroscopically because ofthe difficult access to pathologically loose tissue and because it is very hard to determine how much tightçning or advancement of the lax tissue is clinically necessary. In addition, fixation of advanced or tight~ned soft tissue is more difficult arthroscopicallythan through open surgical methods.
Collagen co~ g tissue is ubiquitous in the human body and provides the cohesiveness of the musculoskeletal system, the structural integrity of the viscera as well as the elasticity of inte~lment Collagen also demonstrates unique characteristics not found in other tissues. A previously recogrlized property of collagen is shrinkage of collagen fibers when elevated in temperature. Collagen fibrils are at their greatest length in the native state of a triple helix. Thermal energy to the collagen molecules disrupts the bonds which st~bi1i7~ the triple helix. The loss of the triple helix structure causes the fibrils to decrease in length or contract, giVillg the collagen co~ ing tissue the appearance of contracting. The degree of contraction is a function of both the height of temperature elevation as well as the length of te.lll)el alLlre elevation.
Thus, the same degree of contraction may be achieved by a high temperature elevation of short duration or by a lower temperature elevation for an extended duration.
Investigators have taken advantage of the unique collag~n features to effect positive ch~nges in non-vascularized collagen conlai~ .g structures. For ........ ..
CA 0226~981 1999-03-16 in.ct~nc~ the use of infrared laser energy to shrink collagen in the cornea of the eye relates to laser keratoplasty and has been described by Sand in U.S. Patent No. 4,976,709. Further, radio frequency (RF) electrical current has been used toreshape the cornea. Such shaping has been reported by Doss in U.S. Patents No.
4,326,529 and 4,381,007.
The capsule of the shoulder joint consists of a synovial lining and three well defined layers of collagen. The fibers of the inner and outer layers extendin 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 intermin~ling of collagen fibers ofthe three layers vary with di~lc;n~ portions ofthe capsule. The li~3~mçntouc components of the capsule are lep[esenled by abrupt thir~toning~ of the inner layer with a significant increase in well olgani~ed coarse collagen bundles in the coronal plane. 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 attçnu~ted and the capsule capacity increases secondary to capsule redlln~nre. In cases of conge~ AI or developmental multi-directional laxity, the ratio of type III to type I collagenfibers is often larger than usual. An appal~ s capable of shrinking the collagencontaining tissue in the shoulder may çlimin~te many of these instabilities.
Further, if this apparatus could be used endoscopically, many of the problems with current endoscopic techniques would be elimin~ted since fixation, tightçning and adv~nrçmrnt would no longer be lequ;led.
The use of endoscopic devices which simply heat the colla~lon c~ ing tissue are not s~ti~f~ctory because ofthe delivery of uncol,llulled energy. High telllpel~lures can cause cell necrosis and may damage the tissue.
There is a need for a method and apparatus which causes coll~gçn co..~ g tissues to contract while minimi7ing cell necrosis and damage to the tissue as well as other organs or bodies which may be present, more particularly, for joints and shoulder capsules. There is a need for a method and apparatus CA 0226~981 1999-03-16 WO 98/11944 PCTrUSg7/16120 capable of causing a collagen cont~ining tissue site at least partially a~ c~nt to a fluid media to contract a selected amount without d~ gh-g the tissue of the - site or any of the surrounding tissues or bodies whether they contain collagen or not.
SUMMARY OF T~E INVENTION
It is an object ofthe present invention to provide a method and appa,~lus configured to contract at least a portion of a selected site of a collagen cont~ining tissue.
Another object of the present invention is to provide a method and appa~L~Is configured to deliver sufficient energy to a s~lected site of a collagen co~ n;..g tissue to produce a contraction of at least a portion of the selected site.
Still another object of the present invention is to provide a method and appa,~lus configured to deliver sufficient energy to a selected site of a collagen co..~ -g tissue to effect an increase in the thermal energy content ofthe selected site.
Yet another object of the present invention is to provide a method and appa~ s configured to deliver sufficient energy to a s~.lected site of a collagen co..l~ g tissue to effect an increase in the telllpe~ re ofthe selected site to a pre-determined level.
A further object of the present invention is to provide a method and apphl~L~Is confi~l.red to deliver s~ffici~nt energy to a s~lected site of a collagen co.. ~ g tissue such that the te.lll)e~ re of the selected site increases to a pre-determined level and remains at or near that level for a selected period of time.
Yet a further object of the present invention is to provide a method and app~L~Is configured to deliver s-lfficient energy to a selected site of a cQll~g~n co..l~;l,ing tissue to create a contraction of collagen fibers.
CA 0226~981 1999-03-16 WO 98tll944 PCT/US97/16120 Still another object of the present invention is to provide a method and appa al-~S with a feedbac~ control device configured to deliver sufficient and controllable energy to a selected site of a collagen conl~ g tissue.
Another object of the present invention is to provide a method and apparatus with a feedback control device configured to deliver sufficient energyto a selected site of a collagen cont~ining tissue positioned at least partiallyadjac~nf to a fluid medium to contract at least a portion of the selected site and produce a therrnal feedbac~ signal representative of a composite of the therrnalenergy contents of at least a portion of the selected site and at least a portion of the adjacçnt fluid me~ m Another object of the present invention is to provide a method and apparatus with a feedbac~ control device configured to deliver suff1cient thermal energy to a selected site of a collagen co,~ ;ng tissue of an unstable joint at least partially positioned ~ c~nt to a fluid me~ m and at least partially repair the instability of the joint.
These and other objects of the invention are obtained with an apparatus for effecting change in at least a portion of a selected site of a collagen ch~ nil~g tissue that is a~ least partially adj~cent to a fluid merli--m The appa~ s inr.lud~c an energy delivery device confi~-red to deliver a level of energy to the selected site of the collagen containing tissue. The energy delivery device in~ludes a distal portion where a sensor is positioned. The sensor provides a signal indicative of the thermal energy content of at least the selected site ofthe collagen col.l~inil-~ tissue and the adjacent fluid m~i.-m to a feedback control unit. The signal is received by the feedb~cl~ control system which adjusts the level of energy supplied to the energy delivery device and delivered to the selected site based on the signal received from the sensor.
In another embodiment, the app~alus in~l~lrles an energy delivery device configured to produce a selected thermal distribution in the s~lected site of the collagen cont~ining tissue to effect a controllable contraction of at least a portion of the collagen fibers. The energy delivery device inrh1des a sensor CA 0226~981 1999-03-16 po~itioned at a distal portion of the energy delivery device. A ~edbncl~ controldevice is coupled to the sensor. A position of the sensor, a gen. ..el, y of thedistal portion of the energy delivery device and the feedbaclr control system provide a controllable energy delivery to the selected site of the collagen col-lAi~ -g tissue.
The energy delivery device is configured to deliver energy from the distal portion to the selected site ofthe collagen co..~ ;.,g tissue. The selected site absorbs at least a portion of the delivered energy and the thermal energy content and temperature of the sçlected site are increased. As the thermal energy content ofthe selected site is increased, thermal energy is con~ cted to the collagen fibers of the s~ected site. Collagen fibers exposed to s..ffil~.içnt thermal energy at least partially lose their triple helix shape and contract. Thus, the delivery of energy to the selected site causes the tel,lpe~ re and the thermal energy content of the sçlected site to hl.;l~ase and create a contraction of at least a portion ofthe collagen co.,~ g tissue site.
In one embodiment, the sensor is located within the distal portion.
During surgery, the distal portion is preferably placed in contact with a portion of the selected site and the fluid medillm adjacçnt to the selected site. Because of this contact, the thermal energy from the selected site and the adjacçnt fluid medium will conduct through the thermally conductive sections of the distal portion to the sensor. The m~gnitu(le of the resulting signal lepresellLs a composite of the thermal energy contents of the selected site and the adjacent fluid medi~lm The sensor provides a signal which is le~ se.l~ e ofthe thermal energy contents of a portion of the fluid metiil~m a~ljacçnt to the selected site as well as at least a portion of the selected site. As a surgeon moves the distal portion about a selected area, it is possible for a surgeon to bring the distal portion into contact with a selected site which has previously been elevated to - the desired temperature for the desired period of time. This second application of energy may quickly elevate the temperature enough to cause cell necrosis or CA 0226~981 1999-03-16 cause the temperature at the sPIected site to remain elevated for longer than the desired period required for the desired level of collagen contraction.
Since the mAgnih1de of the signal provided by the sensor partially l epl esellls the thermal energy of the fluid me~ m the apparatus is responsive to changes in the thermal energy content of the fluid medi~Im Due to the nature of delivering energy to a selected site thermal energy is more disperse in the fluid medium. Because the apparatus responds to thermal energy in the fluid metlillm the appal~l~s reduces cell necrosis resulting from sl~ccescive applications of energy to the selected site. Stray contractions are contraction which occur away from the selected site due to the fluid metlillm becoming elevated in temperature for an PYtçnded period of time. Further response of the apparallls to therrnal energy in the fluid mP~ m can also reduce stray contractions.
DESCRIPTION OF T~IE DRAWINGS
Figure 1 is a perspective plan view of an embodiment of the present invention illustrating an appa~aLus for contracting collagen con~ g tissue.
Figure 2 is a pel ~pe~ re plan view of an embodiment of the present invention illustrating an appa~ ~LIls coupled to an energy source for contracting collagen co.~ ;.,g tissue.
Figure 3 is a perspective plan view of an embodiment of the present invention illustrating an appa~lus for contracting collagen coI~Ail.;..g tissue a desired amount in contact with a collagen co~ e tissue.
Figure 4 is a perspective plan view of an embodiment of the present invention illusll~ling an appal~ s for contracting coIIAgPn co~ ni~ tissue a desired amount delivering heat to a selected site within a setected area.
CA 0226~981 1999-03-16 W O 98111944 PCTrUS97/16120 Figure 5 illustrates the po~itioning of a distal end of an energy delivery device while delivering energy to a selected tissue site and a portion of an ~-ljacent fluid medium and the measurement of a composite telllyel alul e.
Figure 6 is a cross-sectional view of a distal portion of the energy delivery device with a sensor positioned in interior of the distal portion.
Figure 7 is a pe- ~ye~ e plan view of an embodiment of the present invention illustrating an apparatus for contracting collagen CO"~ g tissue a desired amount where the energy delivery surface is a composite construction.
Figure 8 is a sc.h~m~tic of an embodiment of the present invention illustrating a feedbarlr control system.
Figures 9(a)-(d) are perspective plan views of di~relenl embodiments of the present invention illustrating several apparatus, each configured to provide a signal from a sensor such that the signal I eplese..ls thermal energies of di~(~-"
surfaces or me~ -m~.
Figure 10 is a perspective plan view of an embodiment of the present invention illustrating an apparatus with a handpiece, energy delivery device andan operating cannula according to the present invention.
Figure 11 is a perspective plan view of an embodiment of the present illustrating an invention apparatus inrlu~ing an in~ ting layer for preventing damage to surrounding tissues, organs or bodies.
Figure 12 is a perspective plan view of an embodiment of the present invention illustrating an apparatus inrlu-ling a handpiece, an energy delivery CA 0226~981 1999-03-16 W O98111944 PCTrUSg7/16120 device and a sleeve that slides across the surface of the energy delivery deviceto vary the amount of energy delivery device conductive surface.
Figure 13 is a perspective plan view of an embodiment of the present invention illustrating an apparatus inrhl~in~ a thermal in.~l~]~ting layer whichcan be positioned to specify the surface of the distal end section from which the sensor is able to detect thermal energy.
Figure 14 is a sectional view of an embodiment of the present invention illustrating a deflected energy delivery device with a resistive heating elementpositioned in an interior lumen of the energy delivery device.
Figure 15 is a perspective plan view of an embodiment of the present invention illustrating an energy delivery device with a steering wire positionedon the exterior of the energy delivery device.
Figure 16 is a sectional view of an embodiment of the present invention illustrating an energy delivery device with a lumen and a plug that is ~tt~ched to the energy delivery device distal end.
Figure 17 is a sectional view of an embodiment of the present invention illustrating an energy delivery device with an oval cross section and a heating zone in the tissue.
Figure 18 is a sectional view of an embodiment of the present invention illustrating a handle, energy delivery device, ope~ g cannula and a viewing scope, with the viewing scope and energy delivery device po.cition~d in the opel~Lingc~nm~l~
CA 0226~981 1999-03-16 Figure 19 is a cross sectional view of an embodiment of the present invention illustrating a device of Figure 18, taken along the lines 19- 19.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to Figure 1, an apparatus for contracting collagen co.,~ g tissue to a desired level is generally denoted as 10. Apparatus 10 incllldes a handpiece 12 that is preferably made of a thermal in.c~ tin~ material, or an electrode that is electrically inc~ ted Types of such inc~ tin~ materials are well known to those skilled in the art. An energy delivery device 14 is coupled to handle 12 at a proximal end 16 of energy delivery device 14, and may be att~ched thereto. A distal end 18 of energy delivery device 14 in~ des a distal portion 20 which may have a geometry that delivers a controlled amount of energy to tissues in order to achieve a desired level of contraction of collagen fibers in a coilagen cont~ining tissue. Located at distal portion 20 is one or more sensors 22 which provide a signal whose m~nit~lde is leplesel.lalh~e of the amount of thermal energy sensed.
As shown in Figure 2, energy is supplied from an energy source 24 through a cable 26 to energy delivery device 14. Since several types of energy can cause an elevation in the temperature of a collagen cnnt~ining tissues 28.
Energy source 24 can include but is not limited to RF, microwave, ultrasonic, coherent and incoherent light, thermal transfer, and reCict~nce heating.
As illustrated in Figure 3, distal portion 20 is configured to be positioned ~dj~c~nt to a collagen co~ i..;.lg tissue 28 which is at least partially ~djacçnt to a fiuid mP~ m 30. Appropriate collagen co.,l~;nil~g tissues 28 can include but are not limited to vascularized densely collagenous structures such as ten~lonc~lig~mentc, joints capsules and the like. Distal portion 20 is pler~l~ly in contact with collagen cont~ining tissue 28. Fluid medium (gas, liquid, or a combination) 30 may be flowing as would result from irrigating collagen co~ sg tissue 28 or it may be substantially less dynamic or non-moving.
CA 0226~981 1999-03-16 Further, fluid medillm 30 need only be partially fluid and contain bone, portions of organs or other bodies and the like.
Referring now to Figure 4, energy delivery device 14 is configured to deliver energy from distal portion 20 to a selected site 32 ofthe cQll~gen co.. ~ g tissue 28. Selected site 32 receives at least a portion of the delivered energy. Once the energy is delivered it becomes thermal energy causing the thermal energy content and the te~l,?elalLIre of selected site 32 to increase. As the thermal energy content of selected site 32 is increased, thermal energy is con~ucted to the collagen fibers in and around selected site 32. Collagen fibersexposed to sufficient thermal energy loose their triple helix shape. Since the triple helix shape of collagen fibers is the longest shape for collagen fibers, fibers which loose their triple helix shape will contract. Thus, the delivery ofenergy to selected site 32 causes the te,l.pe~ re and the thermal energy contentof selected site 32 to increase and effects collagen fibre contractions. The collagen fiber contraction results in a contraction of collagen co~ il-il-g tissue 28.
Energy delivery device 14 is configured to deliver a level of energy to selected site 32. Sensor 22 provides a signal indicative of a composite te"")e~ re of at least selected site 32 and at least a portion of at least a portion of a(lj~cent fluid me~ m 30 to a feedback controi unit. The signal is received by a feedbac~ control system which adjusts the level of energy supplied to energy delivery device 14 and delivered to selected site 32 based on the signal received from sensor 22.
Throughout the l~eal,.,e,ll, it is often be desirable to effect contractions in a selected area 34 which is larger than a selected site 32. Further, may be desirable to elevate the te-..?e~ re of the selected site 32 or selected area 34 to a desired average temperature for a specified period of time. There are several methods available for achieving these results. For in.ct~nce, one embodiment is to "paint" distal portion 20 across selected area 34 by continually moving distal portion 20 over the surface of the selected area 34 so that the entire selected area CA 0226~981 1999-03-16 W O 98/11944 PCTrUS97tl6120 34 is covered. Selected area 34 can then be brought to the desired temperature and l~ah~ed at that tenlpe.~L~lre by continually moving distal portion 20 over s~lected area 34. In another embodiment, distal portion 20 is left at selected site 32 until the desired temperature is obtained for the desired time. Distal portion 20 is then moved to another selected site 32 for a desired time. This pattern isrepeated until the entire selected area 34 is covered. A colllbina~ion of these techniques may also be used.
Referring now to Figure 5, the composite tell.pe.~ e is a co.l,~.in~;on of at least two diLrerenl temperatures in some ratio. One tempe.~ re 25 is from at least a portion of ~Ajac~nt fluid me~ m 30 and another te.. -l)el~lure 27 of at least a portion of selected tissue site 32. This ratio is a function of different parameters incluAing but not limited to the size, shape, dimensions and geometry of a thermal energy delivery surface of energy delivery device 14, the portion of the thermal energy delivery surface that is in contact with ~Aj~cent fluid medium 30 and selected tissue site 32, the location of sensor 22 in relationship to the thermal energy delivery surface. Current flow 29 which creates molecular friction, and conducted thermal energy are greater in selectedtissue site 32 than in adjacent fluid me~ m 30 due to the higher recist~nce of the tissue.
One embodiment of distal portion 20 is illustrated in Figure 6. Distal portion 20 of energy delivery 14 in~llldes sensor 22 positioned in an interior of distal portion 20. A thermally conductive material 31 at least partially surrounds sensor 22 and a potting compound 33 is in~lndeA Distal end 18 is made of stainless steel, and a nylon coating is po~itioned at an exterior surface of distal portion 20.
At the thermal energy delivery device fluid me~illm interface there is less resistance and a hydro dynarnic force which contribute to a lower reflectedtemperature. At the tissue interface there is a static conductive sit~tion with a higher re~ ance producing higher reflective temperature at the interface.
CA 0226~981 1999-03-16 W O 98/11944 PCTnUS97116120 Energy delivery device 14 can be made of a number of di~erelll materials including but not limited to stainless steel, pl~tim~m, other noble metals and the like. Energy delivery device 14 can be made of a memory metal, such as nickel tit~nillm, cornmercially available from Raychem Corporation, Menlo Park, California. Energy delivery device 14 can also be a composite construction whereby di~lent sections are constructed from di~lellL materials.
Further, it may be desirable for delivery device 14 to be a composite of a firstmaterial 36 which is not conductive to the type of energy being delivered and a second material 38 which is conductive to the type of energy being delivered as shown in Figure 7. Such a construction permits treatment in locations where there are tissues, organs or other bodies present which the surgeon does not wish to expose to the delivered energy. For example, when energy delivery device 14 is introduced into a joint where it is desirable to treat a specific section of the joint and avoid delivery of energy outside of that section, an energy delivery device 14 partially constructed of non-con-~usting material 36 can permit tre~tm~nt One embodiment of an open or closed loop fee~ba~l~ control system 40 is shown in Figure 8. The physician can, if desired, override the closed or openloop feedback control system 40. The fee(lb~c~ control system 40in~hldes an energy source 24, (in~hl(ling but not limited to a RF source), a temperature measuring device 44, a voltage and current measuring device 46, a user display unit 48, a timekeeping device 50, a microprocessor 52 and a user input device 54.
Energy source 24 supplies energy to energy delivery device 14 for delivery to selected site 32. The voltage and current supplied to the energy delivery device 14 are measured on voltage and current measuring device 46 and can display these to the user on user display unit 48. Tell,pelaLu~e measuring device 44 measures the te..~pe~ re at sensor 22, in~lutling the telllpel ~lure of adjacent fluid medium 30 and selected tissue site 32. The CA 0226~981 1999-03-16 tel.lpel~L-Ire measured by temperature measuring device 44 can be displayed to the user on the user display unit 48.
In one embodiment a signal produced by the sensor 22iS received by a feedb~ control system 40. Feedbaçk control system 40 monitors the signal produced by sensor 22 and adjusts the amount of energy or current supplied to energy delivery device 14 according to the m~gnihlde ofthe signal. Energy is supplied to apparatus 10 at a particular rate. The rate of energy delivery can be expressed as power. Power supplied to energy delivery device 14 is adjusted so the temperature at sensor 22iS elevated to a temperature which is desired by theuser and is input to the fee~iba~L control system 40. Once the desired telllpel ~ure is reached, power is adjusted so that the temperature at sensor 22has minor fluctuations but averages to the desired telllpcl ~L~Ire over time. Thus, the feedbac~ control system 40 m~int~in~ the desired tel.lpel~ re at the sensor 22 and correspondingly at the selected site 32.
In another embodiment, feedb~ck control system 40 also monitors time.
In this embodiment both time and temperature are inputs. Thus, once the temperature at sensor 22iS elevated to the desired tel~lpel~ure, fee(lbacl~ control system 40 tracks the length of time sensor 22 averages the desired temperature.
Once the temperature at sensor 22 averages the desired temperature for the desired time, fee~bac~ control system 40 may either stop the delivery of energy or it may inform the user on a user display screen (not shown). Thus, feedback control system 40 can be used to m~int~in the desired temperature at selected site 32 for the desired time.
In one embodiment, microprocessor 52 monitors voltage, current and temperature. Microprocessor 52 car, calculate the power supplied to energy delivery device 14 from the current and voltage and can display the power on the user display unit 48. Microprocessor 52 can also monitor and control a tim~keeping device 50. The microprocessor 52 can signal time~eeping device 50 to begin or stop tracking time. While timekeeping device 50 is tracking time and microprocessor 52 can monitor the passage of time. Microprocessor 52 also CA 0226~981 1999-03-16 receives input from a user input device 54. User input device 54 allows a user to program rnicroprocessor 52 or input information such as the desired temperature or the desired time.
Energy source 24 includes circuitry for mod~ tinp: the power supplied to the energy delivery device 14 according to a signal received from microprocessor 52, thus, microprocessor 52 can control the power supplied to the energy delivery device 14. Microprocessor 52 is programrned to ad~ust the power supplied to energy delivery device 14 so that the tenlpel~ re at sensor 22is ."~ ;"ed at the desired telllpelal~lre for the desired time. The program takes into account at least the desired time, temperature and desired tell~ re in making these adjustments.
Feedback control system 40 is used to obtain the desired degree of contraction by ~ t~ i"g selected site 32, at a desired temperature for a desired time. It has been shown that temperatures of 45 to 90 degrees C can cause collagen fibers contractions. It has also been shown that the degree of collagen fiber contraction is controlled by how long the temperature is elevatedas well as how high it is elevated. Thus, the same degree of contraction can be obtained by exposing selected site 32 to a high temperature for a short period of time or by exposing selected site 32 to a lower t~lllpe-~ re for a longer periodof time. A ~l erel ~ ed range for desired te~npe~ res is about 45 to 75 degrees C, still a more pl~rel~ed range is 45 to 65 degrees C. Before tre~tm~nt the surgeonevaluates the characteristics of the selected site 32 to determine what degree of contraction is necessary and also whether it is app.opl;ate to treat the selected site 32 with a high telllpe~ re for a low period oftime or lower te...pe.~ re for a long period of time. The surgeon then enters into the user input device 54 thedesired te ..pe- ~lure and the desire time. Feedbar.~ control system 40 uses this information to control the delivery of energy to selected site 32 which results in a controlled contraction of collagen colll~ining tissue fibers. The controlled collagen fiber contraction allows for a desired degree of collagen co..~ g tissue contraction.
CA 0226~981 1999-03-16 Additionally, fee~bar.~ control system 40 can be used to effect how deeply within the collagen cont~ining tissue 28 the collagen fiber contractions occur. For instance, elevating the tel.lpe~ re of selected site 32 to the low end of the range effects contractions near the surface of collagen cont~ining tissue28. Elevating the temperature to the high end of the range effects contractions deeper within collagen co.~ g tissue 28. Thus, if the surgeon is dealing with a very thin collagen cont~ining tissue 28 which is adjilcent to tissue which maybe damaged by elevated temperatures, the surgeon may choose to elevate the temperature of selected area 34 to a low temperature for longer periods of time.However, if collagen cont~ining tissue 28 is thicker, the surgeon may choose higher temperatures to effect contractions deeper in collagen cont~ining tissue 28. Thus, the choice of the desired temperature can control the thermal energy distribution and thus the depth of contractions.
Feedback control system 40 further allows apparatus 10 to minimi7e and even prevent cell necrosis (ablation) resulting from exposure to high temperatures. High temperatures can cause excessive destruction and ~icintegration of the collagen fibrillar patterns and cell necrosis. Since feedback control system 40 can m~iht~in the temperature of sensor 22 at a desired temperature, the temperature at selected site 32 does not exceed ablation temperature.
Further, feedback control system 40 can prevent overshoots which may cause cell necrosis. Overshoots occur while raising the te...pe~ re of selected site 32 or selected area 34 to the desired level and temporarily surpassing thatlevel. Some overshoot of the desired te...~)e.~L~Ire will be inherent in most embodiments of feedback control systems, however, it is possible to cause cell necrosis or dissociation if the overshoot is high enough or of long enough duration. Feedb~cl~ control system 40 reduces overshoots by reducing the rate of energy delivery once the selected site 32 te--.l)el~ re is near the desired level.
Thus, when energy is first delivered to a selected site 32, there can be a high rate of energy delivery, however, once the temperature of the selected site is nearing W O 98/11944 PCTrUS97/16120 the desired range, the rzte of energy delivery is reduced ir order to prevent anovershoot. Pro~ g this rampiag down effect,lito a feedbac~ control system 40 is well known to those in the art of feedbac!c control. Note: Some overshoots are ok, but the average ternp rnust fall within a non-dilative range.Sensor 22 can consist of, but is not lir.~ted to, a therrnocouple, a thermistor or phosphor coated optical fibers. The se1lror 22 can be in an interior of the distal portion 20 or on the surface of the distal portion 20 and can further be a single sensor 22 or several sens~rs. It can als~ be a band or patch insteadof a sensor 22 which senses or,ly discrete points.
Sensor 22 provides 2 sigr.al whose m~g~litude is representative ofthe thermal energy content of the surfaces &nd mediums in physical contact Wit}l thesurface of the sensor 22. Thus, if several surfaces or mediumc are in physical contact with sensor 22, the m~gnitllde of the signal provided by sensor 22 will be representative of a composite of the thermal energy contents of those surfaces and/or mediums. Further, the effective suriace of sensor 22 can be increased by wholly enclo~ing sensor 22 ir. a medillm which easily conducts therrnal energy. In this embodiment, thermal energy will be conducted firom the surface of the thermally conductive mediuln to th ser,sor 22. The magnitude of the signal will represent a com?csite OI fl~e ther~r~l energy contents of anysurfaces and mediums in physical co~act with the surface of the thermally conductive medium. For inct~nce~ Figure 9~a) il'ustrates an embodiment where sensor 22 is located within distal portion 20. Fu.rther, distal portion 20 is inphysical contact with a portion Gf the selec.e~ site 32 and fluid medillm 30 atljacPnt to the selected site 32. r'ec~ r~e cf this cor.tact, the thermal energy from selected site 32 and adjacent fluid rr.ediurn.30 cond.lcts through the thermally conductive sections cf dirtal ~" crt.~n 23 t~ sensor 22. The m~,~nitude of the resulting signal provide& by senrcr 22 represen~s the com~osite thermal energy content of selected site 32 and at leas~ a ~~ortic;l of ~ ctont fluid meditlm 30.
CA 0226~981 1999-03-16 By strategically positioning and configuring sensor 22, it is possible to design the distal portion 20 such that signal represents the thermal energy content of specific surfaces or medillm.c. For in~t~nce, Figure 9(b) illustrates an embodiment where the sensor 22 is positioned such that the thermal energy S con~llcted to the sensor is from substantially only sPIected site 32. Thus, sensor 22 provides signal which is l ep~ ese"l~Live of the therrnal energy content of substantially only selected site 32. Further, Figure 9(c) shows an embodiment where sensor 22 is configured as a band and positioned such that the thermal energy conducted to sensor is from substantially only fluid medil]m 30 ~1jaeçnt to selected site 32. Thus, sensor 22 provides a signal which ep, ese"ls substantially only the therrnal energy content of the ~dj~cçnt fluid me-lium Figure 9(d) illustrates another embodiment where fluid medillm adjacent to selected site 32 contains other tissue, organs or bodies 56. In thisembodiment, the signal provided by sensor 22 le~ s~nls a composite ofthe thermal energy contents of selected site 32 and ~dj~ nt fluid medillm 30 as well as the other tissues, organs or bodies 56.
Sensor 22 provides the composite signal of thermal energy and temperature whether fluid merlillm 30 is flowing or non-flowing. When the surgeon chooses to deliver energy to selected area 34 by moving distal portion 20 from selected site 32 to another, it is possible to bring distal portion 20 into physical contact with a selected site 32 which has previously been elevated to the desired temperature for the desired period of time. This second application of energy may quickly elevate the tenli)e,~u~e enough to cause cell necrosis or may cause the temperature at selected site 32 to remain elevated forlonger than the desired period causing the collagen fibers to contract more thandesired.
Positioning sensor 22 to provide a signal which represel,L~ a composite of the therrnal energy contents of selected site 32 as well as ~dj~cPnt fluid medillm 30 reduces cell necrosis or over contraction caused by a second application of energy. As energy delivery device 14 delivers energy to selected .
CA 0226~981 1999-03-16 site 32 it also delivers energy to fluid meriillm 30 which is in physical contact with energy delivery device 14 adjaG~nt to selected site 32. This delivery of energy to fluid medium 30 causes the thermal energy content of fluid medium 30 to increase. The thermal energy content of fluid me~illm 30 ~dj~cent to S selected site 32 also rises due to conduction of thermal energy from se}ected site 32 to fluid tne~ m 30. Furthermore, due to convection resulting from the movement of distal portion 20, thermal energy disperses through fluid m~ium 30 at a quicker rate than through collagen co..~ g tissue 28.
As a result ofthe energy ~lanar~la described above, the colleal)ol1dillg elevations in temperature will be more dispersive in fluid me~ m 30 than in selected site 32. Thus, the signal produced by sensor 22 is di~rent when dis~:alportion 20 is placed a(ljacçnt to a previously heated selected site 32 than whendistal portion 20 is placed in a selected site 32 away from any previously heated selected sites 32. Although the selected sites 32 in the former and latter caseswill have similar thermal energies, in the former case, the dispersive energy influid medium 30 causes the fluid medium 30 to have a higher thermal energy content than in the latter case. Since sensor 22 provides a signal whose m~gnit~lde ~eplesen~s a composite ofthermal energies of fluid medi~lm 30 ~djacent to selected site 32, in the former case sensor 22 provides a signal to feedback control system 40 indicating an elevated thermal energy content and reduces the amount of energy delivered to selected site 32. This reduced energy delivery decreases cell necrosis or o~lco"l,action near selected site 32. The same is true in those in~t~nres when distal portion 20 is again passed over a previously heated selected site 32.
It will also be applec;aled that when sensor 22 is positioned where it provides a signal representing a composite in~lu~ing adjacent fluid me~illm 30 when the surgeon chooses to paint s~lected area 34 rather than moving from one selected site 32 to another. The surgeon will want to keep the te~ ei~ure of an entire selected area 34 within a specific range during the pau,~h~g process. As distal portion 20 is painted across s~lected area 34 it leaves a path which has CA 0226~981 1999-03-16 W O 98/11944 PCT~US97116120 been heated and may intersect that path several times during the process of keeping the temperature within the desired range. As selected area 34 is covered and distal portion 20 intersects the heated path it is desirable to deliver more energy to areas which are not in the path and consequently have not been previously heated. It is also desirable to deliver less energy to areas which are part of the path and have previously been heated. By delivering energy this way, the thermal energy content of the selected area 34 will approach a uniform thermal energy across the selected area.
As described above, thermal energy can be more dispersive in fluid medillm 30. As a result, when distal portion 20 is moved toward a previously heated path sensor 22 provides a di~erenl signal than it would if it were not traveling toward a previously heated path. Fluid mçdillm 30 will have a higher thermal energy content in the forrner case than in the latter case. Since sensor22 provides a signal whose m~nitllde is related to a composite of the thermal energies of fluid m~dillm 30 adjacent to selected site 32 and the selected tissue site 32 in the forrner case sensor 22 provides a signal to feedbar.~ control system 40 indicating an elevated thermal energy content and reduces the amount of energy delivered to selected site 32. As a result ofthe elevated therrnal energycontent, feedback control system 40 reduces the amount of energy delivered in the former case. The result allows the te,.l~e,al~lre across the selected area 34 to approach uniro~ ily. U~iiro",li~y of temperature is desirable as it reduces cellnecrosis or overcontractions near path intersections.
Positioning sensor 22 such that it provides a signal which I epl t;senls a composite ofthermal energies inr~ ing adjac~nt fluid mç~lium 30 can also reduce stray contractions. Stray contractions are undesired contractions of collagen fibers outside selected area 34. As described above, while energy is delivered to selected area 34, the thermal energy content of fluid mç(lium 30 also increases. During an extended 1l ~llllenl it is possible for the thermal energy content of fluid medium 30 to rise considerably. If the thermal energy content of fluid mç~lillm 30 remains elevated for an extended period oftime it is CA 0226~981 1999-03-16 possible for the conduction of thermal energy from fluid me~ m 30 to collagen co.~ .g tissue 28 to elevate the te~ )e.~ re of collagen coi~Ai.~ing tissue 28 sufficiently to cause undesired contractions of collagen fibers and may occur outside sele~cted area 34. These stray contractions are even more of a problem when the fluid mer~il-m 30 is flowing since the flow will carry the heated fluidmedium 30 away from the selected area.
These stray contractions are reduced by positioning sensor 22 to provide a composite signal which inr.l~ldes at least a portion of fluid medil-m adj~cPnt to the selected site 32. For inct~nçe, when the thermal energy content of fluid me~ m 30 is raised, the signal will be di~renl than when it is not and the energy delivery is adjusted accordingly. Since sensor 22 provides a signal whose m~gnit~lde is related to a composite which inr.l~ldes the fluid medium 30 adjac~nt to the sPIected site 32, in the forrner case sensor provides a signal to feedb~cl~ control system 40 indicating an elevated thermal energy content and reduces the amount of energy delivered to s~lected site 32. The reduced energy delivery reduces the amount of energy delivered to fluid medium 30 and concçquçntly reduce stray contractions.
Apparatus 10, comprising handpiece 12 and energy delivery device 14, is adapted to be introduced through an operating cannula 58 for percutaneous applications. It will be appreciated that apparatus 10 may be used in non-percutaneous applications and that an operating cannula 58 is not n~cecc~ly in the broad application of the invention.
As illustrated in Figure 10, appar~ s 10 can also include, as an integral member, an operating cannula 58 which can be in the form of a hypodermic trocar with tlim~ncions of about 3 to 6 mm outside ~ m~o,ter, with tubular geometries such as those of standard col-.lllel.;ially available ope.~ling ç~nm~l~c Operating cannula 58 can be made of a variety of biocompatible materials innl~lding but not limited to stainless steel, and the like.
Ope-~Ling cannula 58 has a cannula p.o~umal end that att~hes to handpiece 12 and a cannula distal end 60 which can have a sharp or piercing end CA 0226~981 1999-03-16 W O 98/11944 PCT~US97/16120 for penetrating body structures in order to introduce energy delivery device 14 to a selected site 32. Energy delivery device 14 is positioned within an interior lumen of operating cannula 58 and is extendable beyond cannula distal end 60 in order to reach selected site 32. Energy delivery device 14 can be advanced and retracted in and out of operating cannula 58 by activating a deployment button 62 which is located on the exterior of handle 12. Deployment button 62 is p~ere~al)ly activated by the operator merely by sliding it, which causes energy delivery device 14 to advance in a direction away from cannula distal end 60.
Deployment button 62 can be pulled back, causing a retraction of energy delivery device 14 towards cannula distal end 60. In many in~t~ncçc, energy delivery device 14 is retracted to be positioned entirely within operating cannula 14. Energy delivery device 14 can also be deployed with fluid hydraulics, pne~-m~tics, servo motors, linear actuators, and the like.
In Figure 11, distal portion 20 of energy delivery device 14 incl~ldes an ing~ ting layer 64 which is substantially impenetrable to the energy delivered to collagen co~ h~ g tissue 28. Specifically, in the case of an RF energy source 24, electrical insulation can be used. Insulation 64 can be formed on energy delivery device 14 such that a miniml~m of energy is delivered to tissue,organs or other bodies which the surgeon does not wish to treat. For example, when energy delivery device 14 is introduced into a tight area, and only one surface of the tight area is to be treated, then it is desirable to avoid delivering energy outside of that surface. The inclusion of in.c~ ting layer 64 accomrli.~hes this result. Suitable insulation materials include but are not limited to polyamide, epoxy varnish, PVC and the like.
The area of energy delivery device 14 that serves as a conductive surface 66 can be ~ju~ted by the inclusion of an in~ ting sleeve 68 (Figure 12) that is positioned around energy delivery device 14. Sleeve 68 may be advanced and retracted along the surface of energy delivery device 14 in order to increase ordecrease the surface area of conductive surface 44 that is directed to collagen cont~ining tissue 28. Sleeve 68 can be made of a variety of materials inr.ll~(ling _ _ . . . . . .
CA 0226~981 1999-03-16 W O 98/11944 PCTrUS97/16120 but not limited to nylon, polyamides, 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 68, inclu~ing but not limited to printed circuitry with multiple circuits that can be individually activated, and the like.
As illustrated in Figure 13, distal portion 20 of energy delivery device 14 incll-des a thermally ine~ ting layer 70 which is subst~nti~lly impenetrable to thermal energy. Thus, thermal inc~ ting layer 70 can be used to limit the arnount of selected site 32 that contributes to the te~llpe.~lule detected by sensor ~2. For example, by in~ ting only distal end 18 of distal portion 20 substantially only thermal energy from fluid medi~m 30 ~dj~c~nt to selected site 32 is con~llcted to sensor 22. Thus, the m~gnitl-de ofthe signal produced by the sensor 22 represents substantially only the thermal energy content of fluid medium 30 adj~c.çnt to selected site 32. Thermal energy in~ ting layer 70 can also be used in conjunction with a delivered energy jn~ ting layer 64 to cover identical areas or different areas. Thermal in~ul~ting layer 70 can be constructed of the same material as the delivered energy in.~ tinE layer 64.
For many applications, it is necec~ry to have distal portion 20 become deflected. In Figure 14, a resistive heating element 72 can be positioned in an interior lumen of energy delivery device 14 which is at least partially made of memory metal. Resistive heating element 72 can be made of a suitable metal that transfers heat to energy delivery device 14, causing distal portion 20 to become deflected when the temperature of energy delivery device 14 reaches a level that the memory metal is caused to deflect, as is well known in the art.
Not all of energy delivery device 14 need be made of the memory metal. It is possible that only distal portion 20 be made of the memory metal in order to effect the desired deflection. When deflection is caused by heating memory metal, it is desirable to insulate sensor 22 from the effects of the resistive heating element 22. One method of doing this is demonstrated in Figure 12 CA 0226~981 1999-03-16 W O 98/11944 PCT~US97/16120 where thermal inc~ tin~ layer 70 is located between the distal portion 20 and sensor 22 where sensor 22is a band.
Deflection can also be accomplished meçh~ni~ lly A steering wire, or other mech~nic~l structure, is att~çhed to either the exterior or interior of energy delivery device 14. A deflection button 74, located on handle 12 (Figure 10), isactivated by the physician, causing a steering wire 76 (Figure 15) to tighten, and impart an retraction of energy delivery device 14, resulting in a deflection of distal portion 20. It will be app-eciated that other mech~nical mec.l~ ,.,g can be used in place of steering wire 76. The deflection may be desirable for selected sites 32 that have difficult access, and it is nec~cs~,y to move about a non-planar collagen conl~;..it-g tissue 28. By deflecting distal portion 20, theopportunity to provide more even thermal energy to se~ected site 32 is achieved,and the possibility of ablating or dissociation of collagen material is greatly reduced.
As shown in Figure 15, steering wire 76 att~hes to a flat formed on the exterior of energy delivery device 14. Wire EDM technology can be used to form the flat on energy delivery device 14. A "T" bar configuration is illustrated in Figure 15. Chemical etching may be used to create the T bar.
Steering wire 76 need not be an actual wire. It can also be a high tensile strength cord such as Kevlar. Steering wire 76 can be made of stainless steel flat wire, sheet material, and the like.
As shown in Figure 16 energy delivery device 14 can be tubular in nature with a central lumen. Distal portion 20 can include a conductive plug 78 that is sealed to distal portion 20 by welding, e-beam, laser and the like.
2~ Energy delivery device 14 can have a variety of dif~ geol,lt;llicconfigurations which can vary based on the type and shape of collagen co.,~ in~ tissue 28 to be heated. In Figure 17, energy delivery device 14 has an oval cross section. The oval cross section provides a greater conductive surface 66 area that is in contact with collagen col ~ g tissue 28. A larger zone of heating to collagen co.,l~ g tissue 28 is provided. The thermal CA 0226~981 1999-03-16 W 0 98/11944 PCTrUS97/16120 gradient within collagen CG~ g tissue 28iS more even and the possible dissociation or breakdown of the collagen fibers is reduced.
As illustrated in Figures 18 and 19, operating cannula 58 may include a viewing scope 80 which may be positioned adjacP-nt to energy delivery device 14. Viewing scope 80 provides a field of view 82,pe~ ing the surgeon to view while delivering energy to selected site 32 and contracting collagen con~ g tissue 28. Viewing scope 80 can include a bundle of light e fibers and optical viewing elenn~.nte Alternatively, the surgeon can view the procedure under al~h,oscopic viell~li7.~tion.
The present invention also provides a method of contracting collagen co~ i-lg tissue 28. The collagen co"l~ g tissue 28iS contracted to a desired shrinkage level while ll.;~l;..,;~.;i-g cell necrosis as well as damage to surrounding organs and other bodies. It can be used in the joints such as 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 di~l enL
applications, not merely those specifically mentioned in this specification.
Some specific applications include joint capsules, specifically the gleno-humoral joint capsule ofthe shoulder, herniated discs, the m~niecl~.e ofthe knee, in the bowel, for hiatal hernias, abdominal hernias, bladder suspensions, tissuewelding, DRS, and the like.
The surgeon determines which collagen cont~ining tissues 28 require contraction and how much shrinkage should occur. The surgeon then selects an area of the collagen cor.~ -g tissue 28 for shrinkage. The surgeon can find the selected area 34 by using arthroscopic viewing or using the apparatus 10 include a viewing scope 80. Once the surgeon places the energy delivery device 14 next to the selected site 32, the surgeon soon begins delivery of energy.
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 WO 98/llg44 PCT/tJS97/16120 invention concepts herein. The invention, therefore, is not to be restricted except in the spirit of the appended claims.
What is claimed is:
As illustrated in Figures 18 and 19, operating cannula 58 may include a viewing scope 80 which may be positioned adjacP-nt to energy delivery device 14. Viewing scope 80 provides a field of view 82,pe~ ing the surgeon to view while delivering energy to selected site 32 and contracting collagen con~ g tissue 28. Viewing scope 80 can include a bundle of light e fibers and optical viewing elenn~.nte Alternatively, the surgeon can view the procedure under al~h,oscopic viell~li7.~tion.
The present invention also provides a method of contracting collagen co~ i-lg tissue 28. The collagen co"l~ g tissue 28iS contracted to a desired shrinkage level while ll.;~l;..,;~.;i-g cell necrosis as well as damage to surrounding organs and other bodies. It can be used in the joints such as 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 di~l enL
applications, not merely those specifically mentioned in this specification.
Some specific applications include joint capsules, specifically the gleno-humoral joint capsule ofthe shoulder, herniated discs, the m~niecl~.e ofthe knee, in the bowel, for hiatal hernias, abdominal hernias, bladder suspensions, tissuewelding, DRS, and the like.
The surgeon determines which collagen cont~ining tissues 28 require contraction and how much shrinkage should occur. The surgeon then selects an area of the collagen cor.~ -g tissue 28 for shrinkage. The surgeon can find the selected area 34 by using arthroscopic viewing or using the apparatus 10 include a viewing scope 80. Once the surgeon places the energy delivery device 14 next to the selected site 32, the surgeon soon begins delivery of energy.
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 WO 98/llg44 PCT/tJS97/16120 invention concepts herein. The invention, therefore, is not to be restricted except in the spirit of the appended claims.
What is claimed is:
Claims (44)
1. An apparatus for effecting a change in at least a portion of a selected site of a collagen containing tissue that is adjacent to an at least partially fluid medium, comprising:
an energy delivery device including a proximal portion and a distal portion configured to deliver sufficient energy to the selected site of a collagen containing tissue to effect a contraction in at least a portion of the selected site of a collagen containing tissue;
a sensor positioned at a the distal portion of the energy delivery device to detect a thermal energy from the selected site of a collagen containing tissue and at least a portion of the adjacent at least partially fluid medium, the sensor producing a thermal feedback signal which represents a composite of the thermal energy detected from the selected site of a collagen containing tissue and at least a portion of the adjacent at least partially fluid medium; and a feedback control system coupled to the sensor and configured to receive the thermal feedback signal and adjust a level of energy delivered to the selected site of a collagen containing tissue.
an energy delivery device including a proximal portion and a distal portion configured to deliver sufficient energy to the selected site of a collagen containing tissue to effect a contraction in at least a portion of the selected site of a collagen containing tissue;
a sensor positioned at a the distal portion of the energy delivery device to detect a thermal energy from the selected site of a collagen containing tissue and at least a portion of the adjacent at least partially fluid medium, the sensor producing a thermal feedback signal which represents a composite of the thermal energy detected from the selected site of a collagen containing tissue and at least a portion of the adjacent at least partially fluid medium; and a feedback control system coupled to the sensor and configured to receive the thermal feedback signal and adjust a level of energy delivered to the selected site of a collagen containing tissue.
2. The apparatus of claim 1, wherein the energy delivery device is constructed from platinum.
3. The apparatus of claim 1, wherein the energy delivery device is constructed from stainless steel.
4. The apparatus of claim 1, wherein the energy delivery device is constructed from memory metal.
5. The apparatus of claim 1, wherein the energy delivery device is a composite construction.
6. The apparatus of claim 5, wherein a component of the composite construction does not conduct energy delivered by the energy delivery device.
7. The apparatus of claim 1, wherein the energy delivery device is an RF energy delivery device coupled to an RF energy source.
8 The apparatus of claim 1, wherein the energy delivery device is a resistive heating element coupled to a resistive heating source.
9. The apparatus of claim 1, wherein the energy delivery device is a microwave probe coupled to a microwave source.
10. The apparatus of claim 1, wherein the sensor is a thermocouple.
11. The apparatus of claim 1, wherein the sensor is a thermistor.
12. The apparatus of claim 1, wherein the sensor is an optical coated fiber.
13. The apparatus of claim 1, further comprising:
a handle coupled to the proximal portion of the energy delivery device.
a handle coupled to the proximal portion of the energy delivery device.
14. The apparatus of claim 1, further comprising:
an electrical insulator positioned at least partially around an exterior surface of the energy delivery device.
an electrical insulator positioned at least partially around an exterior surface of the energy delivery device.
15. The apparatus of claim 1, further comprising:
a thermal insulator positioned at least partially around an exterior surface of the energy delivery device.
a thermal insulator positioned at least partially around an exterior surface of the energy delivery device.
16. The apparatus of claim 1, further comprising:
an electrical insulator positioned at least partially around an exterior surface of the energy delivery device and a thermal insulator positioned at least partially around an exterior surface of the energy delivery device.
an electrical insulator positioned at least partially around an exterior surface of the energy delivery device and a thermal insulator positioned at least partially around an exterior surface of the energy delivery device.
17. The apparatus of claim 1, further comprising:
a thermally insulating material coupling the sensor to an exterior surface of the distal portion.
a thermally insulating material coupling the sensor to an exterior surface of the distal portion.
18. The apparatus of claim 1, further comprising.
a thermally conductive material coupling the sensor to an exterior surface of the distal portion.
a thermally conductive material coupling the sensor to an exterior surface of the distal portion.
19. The apparatus of claim 1, wherein the sensor is positioned to detect a thermal energy from substantially only the selected site of a collagen containing tissue.
20. The apparatus of claim 1, further comprising a second sensor.
21. The apparatus of claim 1, wherein the sensor is a band at least partially positioned on an exterior surface of the distal portion.
22. The apparatus of claim 1, wherein the sensor is positioned in an interior of the distal portion of the energy delivery device.
23. The apparatus of claim 1, wherein the sensor is a positioned on an exterior surface of the distal portion and extends to an interior of the distal portion.
24. The apparatus of claim 1, wherein the distal portion is steerable.
25. The apparatus of claim 1, wherein at least a portion of the energy delivery device is configured to be introduced through an operating cannula.
26. The apparatus of claim 1, wherein at least a portion of the distal portion is hollow.
27. The apparatus of claim 26, wherein the distal portion has a substantially uniform wall thickness.
28. The apparatus of claim 26, further including a potting compound located in the hollow interior for positioning the sensor.
29. An apparatus for contracting a collagen fibers in a selected site of a collagen containing tissue at least partially is adjacent to a fluid medium, comprising:
an energy delivery device including a proximal portion and a distal portion configured to provide a selected thermal distribution in the selected site of a collagen containing tissue and effect a controllable contraction of at least a portion of the collagen fibers;
a sensor positioned at the distal portion of the energy delivery device;
and a feedback control system coupled to the sensor, wherein a position of the sensor, a geometry of the distal portion of the energy delivery device and the feedback control system provide a controllable energy delivery to the selected containing tissue site.
an energy delivery device including a proximal portion and a distal portion configured to provide a selected thermal distribution in the selected site of a collagen containing tissue and effect a controllable contraction of at least a portion of the collagen fibers;
a sensor positioned at the distal portion of the energy delivery device;
and a feedback control system coupled to the sensor, wherein a position of the sensor, a geometry of the distal portion of the energy delivery device and the feedback control system provide a controllable energy delivery to the selected containing tissue site.
30. A method for contracting a collagen fibers in a selected collagen containing tissue site at least partially adjacent to a fluid medium, comprising:
providing an apparatus including an energy delivery device with a proximal portion, a distal portion, a sensor and a feedback control system coupled to the sensor;
delivering sufficient energy to the collagen containing tissue site to produce a selected contraction of the collagen containing tissue site;
detecting a thermal energy at the selected collagen containing tissue site and at least a portion of the adjacent fluid medium;
producing a thermal feedback signal which represents a composite of a thermal energy of at least a portion of the selected collagen containing tissue site and the adjacent fluid medium; and adjusting a level of energy delivered to the selected collagen containing tissue site.
providing an apparatus including an energy delivery device with a proximal portion, a distal portion, a sensor and a feedback control system coupled to the sensor;
delivering sufficient energy to the collagen containing tissue site to produce a selected contraction of the collagen containing tissue site;
detecting a thermal energy at the selected collagen containing tissue site and at least a portion of the adjacent fluid medium;
producing a thermal feedback signal which represents a composite of a thermal energy of at least a portion of the selected collagen containing tissue site and the adjacent fluid medium; and adjusting a level of energy delivered to the selected collagen containing tissue site.
31. The method of claim 30, wherein sufficient energy is delivered to generate a selected thermal distribution in the selected a collagen containing tissue site to effect a contraction of the collagen fibers irrespective of a temperature differential between the collagen containing tissue site and the adjacent fluid medium
32. The method of claim 30, wherein the collagen containing tissue site is a ligament.
33. The method of claim 30, wherein the collagen containing tissue site is a joint capsule.
34. The method of claim 30, wherein the collagen containing tissue site is a vascularized densely collagenous structure.
35. The method of claim 30, wherein the collagen containing tissue site is a connective tissue.
36. The method of claim 30, wherein the feedback control system is configured to be overridden by a surgeon.
37. The method of claim 30, wherein the level of energy is adjusted such that a temperature at the selected site is maintained at about 45 to 75 degrees C.
38. The method of claim 30, wherein the level of energy is adjusted such that a temperature at the selected site is maintained at about 45 to 65 degrees C.
39. The method of claim 30, wherein a level of energy applied to the collagen containing tissue site is adjusted such that a temperature at the selected site is maintained at about a desired temperature.
40. The method of claim 30, wherein the level of energy applied to the collagen containing tissue site is adjusted such that a temperature at the selected site is maintained at about a desired temperature for a desired time.
41. The method of claim 30, wherein the level of energy applied to the collagen containing tissue site is adjusted such that overshoots are minimized.
42. The method of claim 30, wherein the adjacent fluid medium is at least partially flowing.
43. The method of claim 30, wherein an energy applied to the collagen containing tissue site is adjusted to minimize cell necrosis.
44. The method of claim 30, wherein an energy applied to the collagen containing tissue site is adjusted to eliminate cell necrosis.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US71498796A | 1996-09-17 | 1996-09-17 | |
| US08/714,987 | 1996-09-17 | ||
| PCT/US1997/016120 WO1998011944A1 (en) | 1996-09-17 | 1997-09-17 | Method and apparatus for controlled contraction of soft tissue |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2265981A1 true CA2265981A1 (en) | 1998-03-26 |
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ID=24872259
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002265981A Abandoned CA2265981A1 (en) | 1996-09-17 | 1997-09-17 | Method and apparatus for controlled contraction of soft tissue |
Country Status (5)
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| EP (1) | EP0998331A1 (en) |
| JP (1) | JP2001501505A (en) |
| AU (1) | AU4583297A (en) |
| CA (1) | CA2265981A1 (en) |
| WO (1) | WO1998011944A1 (en) |
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| US6757565B2 (en) | 2002-02-08 | 2004-06-29 | Oratec Interventions, Inc. | Electrosurgical instrument having a predetermined heat profile |
| DE102004031927A1 (en) * | 2004-06-23 | 2006-01-19 | Aesculap Ag & Co. Kg | Surgical instrument |
| US8979838B2 (en) | 2010-05-24 | 2015-03-17 | Arthrocare Corporation | Symmetric switching electrode method and related system |
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| US4326529A (en) | 1978-05-26 | 1982-04-27 | The United States Of America As Represented By The United States Department Of Energy | Corneal-shaping electrode |
| US4381007A (en) | 1981-04-30 | 1983-04-26 | The United States Of America As Represented By The United States Department Of Energy | Multipolar corneal-shaping electrode with flexible removable skirt |
| US4976709A (en) | 1988-12-15 | 1990-12-11 | Sand Bruce J | Method for collagen treatment |
| US5186181A (en) * | 1990-07-27 | 1993-02-16 | Cafiero Franconi | Radio frequency thermotherapy |
| EP0558297B1 (en) * | 1992-02-25 | 1997-04-16 | Japan Crescent Inc. | Heated balloon catheter |
| FR2689768B1 (en) * | 1992-04-08 | 1997-06-27 | Inst Nat Sante Rech Med | APPLICATOR DEVICE FOR MICROWAVE HYPERTHERMIA IN A CERTAIN BODY. |
| AU650129B2 (en) * | 1992-04-10 | 1994-06-09 | Zhihui Lin | Meat slicing apparatus |
| US5352868A (en) * | 1992-05-01 | 1994-10-04 | Hemostatic Surgery Corporation | Resistance feedback controlled power supply |
| US5720718A (en) * | 1992-08-12 | 1998-02-24 | Vidamed, Inc. | Medical probe apparatus with enhanced RF, resistance heating, and microwave ablation capabilities |
| US5464437A (en) * | 1993-07-08 | 1995-11-07 | Urologix, Inc. | Benign prostatic hyperplasia treatment catheter with urethral cooling |
| US5458597A (en) * | 1993-11-08 | 1995-10-17 | Zomed International | Device for treating cancer and non-malignant tumors and methods |
| US5683384A (en) * | 1993-11-08 | 1997-11-04 | Zomed | Multiple antenna ablation apparatus |
| US5458596A (en) * | 1994-05-06 | 1995-10-17 | Dorsal Orthopedic Corporation | Method and apparatus for controlled contraction of soft tissue |
| FR2743498B1 (en) * | 1996-01-12 | 1998-03-06 | Sadis Bruker Spectrospin | PROBE, IN PARTICULAR URETHRAL PROBE, FOR THE HEATING OF TISSUES BY MICROWAVES AND FOR THE MEASUREMENT OF TEMPERATURE BY RADIOMETRY |
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1997
- 1997-09-17 JP JP10514754A patent/JP2001501505A/en not_active Ceased
- 1997-09-17 AU AU45832/97A patent/AU4583297A/en not_active Abandoned
- 1997-09-17 WO PCT/US1997/016120 patent/WO1998011944A1/en not_active Application Discontinuation
- 1997-09-17 EP EP97944305A patent/EP0998331A1/en not_active Withdrawn
- 1997-09-17 CA CA002265981A patent/CA2265981A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| WO1998011944A1 (en) | 1998-03-26 |
| JP2001501505A (en) | 2001-02-06 |
| AU4583297A (en) | 1998-04-14 |
| EP0998331A1 (en) | 2000-05-10 |
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| EEER | Examination request | ||
| FZDE | Discontinued |