Combined hyperthermia and dilation catheter

• US 5,496,271 A
• Filed: 06/16/1993
• Issued: 03/05/1996
• Est. Priority Date: 09/14/1990
• Status: Expired due to Term

• Current Assignee: Ams Research Corporation (Endo International PLC), Pfizer Inc.
• Original Assignee: American Medical Systems Incorporated (Endo International PLC)
• Inventors: Burton, John H., Cook, Timothy C., Tihon, Claude
• Primary Examiner(s): MCDERMOTT, CORRINE MARIE
• Application Number:
  US08/078,367
• Time in Patent Office: 993 Days
• Field of Search: 604/20, 604/53-54, 604/96, 604/101, 604/113-114, 606/27-31, 607/96, 607/101-102, 607/113-116, 607/138, 607/143
• US Class Current: 607/27
• CPC Class Codes: A61B 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 18/1815 using microwaves
• CPC Class Codes: A61B 2017/00274 Prostate operation, e.g. prostatectomy, turp, bhp treatment
• CPC Class Codes: A61B 2018/00166 Multiple lumina
• CPC Class Codes: A61B 2018/00547 Prostate
• CPC Class Codes: A61B 2018/1861 with an instrument inserted into a body lumen or cavity, e.g. a catheter
• CPC Class Codes: A61F 7/123 using a flexible balloon containing the thermal element
• CPC Class Codes: A61M 2025/1084 having features for increasing the shape stability, the reproducibility or for limiting expansion, e.g. containments, wrapped around fibres, yarns or strands
• CPC Class Codes: A61M 25/1011 Multiple balloon catheters
• CPC Class Codes: A61M 29/02 Dilators made of swellable material balloon catheters for angioplasty A61M25/104

Abstract

An apparatus and method for treatment of conditions in which it is desired to simultaneously hyperthermally treat diseased target tissue in a patient and dilate a lumen of a patient which is compressed and/or obstructed by the diseased target tissue and/or surrounding tissue is disclosed. The apparatus generally includes a catheter for insertion into a lumen of the patient, such as in the prostatic urethra; an antenna for applying microwave or radio frequency energy to the selected target tissue to produce hyperthermal effects therein, thereby causing therapeutic alteration of the selected target tissue cells; a dilation balloon for simultaneously dilating the lumen of the patient and for compressing tissue to restrict blood flow to said tissue, thereby reducing the heat sink effect of blood-supplied tissue absorbing heat energy applied thereto, enabling both greater uniformity of heating in selected target diseased tissue and a reduction in the amount of power required to supply an effective level of energy to the selected target diseased tissue; and a fixation balloon for securing the apparatus during treatment. The apparatus and method are particularly adapted to the treatment of diseases of the prostate, such as benign prostatic hypertrophy (BPH), prostatitis and prostatic cancer, as well as in the treatment of certain tumors of the esophagus and the gastro-intestinal tract.

Claims

1. A method for treatment of conditions in which it is desired to simultaneously hyperthermally treat diseased target tissue in a patient and dilate a lumen of a patient which is being compressed and obstructed by said diseased target tissue and surrounding tissue, said method comprising the steps of:

(a) inserting into the lumen of the patient an apparatus comprising;

(a.i) an outer catheter having a distal end, a proximal end having a plurality of ports therein, and a plurality of lumens situated through said outer catheter, said lumens including a lumen adapted for carrying heating means, inlet and outlet lumens respectively adapted for carrying a fluid into and out of at least one of an inflatable dilation balloon and an inflatable fixation balloon, said fluid being for the inflation of said balloons and alternatively also for acting as a coolant; and

up to one or more separate lumens adapted for performing one or more of the functions of carrying temperature sensing means;

circulating a coolant fluid through the outer catheter when said fluid for the inflation of said dilation and fixation balloons is not also a coolant;

carrying catheter guiding means; and

for drainage of fluid;

such that there is a corresponding port in said proximal end of said outer catheter which cooperates with each lumen in said outer catheter;

(a.ii) an inner catheter member, mounted in said outer catheter, and having a distal end, a proximal end, and a plurality of lumens therethrough;

(a.iii) heating means, axially mounted at said distal end of said inner catheter member and extending within one of said plurality of lumens in said inner catheter member provided therefor, said heating means being for applying energy to selected target tissue to produce hyperthermal effects therein, thereby causing a therapeutic alteration of cells in said target tissue;

(a.iv) an inflatable dilation balloon mounted at the distal end of the outer catheter for accomplishing at least one of the functions of enlarging an obstructed lumen in the vicinity of said target tissue by compressing obstructive tissue, and restricting blood flow to at least one of said target tissue and to non-target tissue in the vicinity of said target tissue, in order to reduce the energy absorbing heat sink effect produced by blood-enriched tissue, thereby causing a more complete and more uniform absorption of energy by said target tissue;

said dilation balloon having a preform diameter, and an oriented diameter greater than said preform diameter, such that the ratio of the oriented diameter to the preform diameter is from about 4.0 to about 7.0;

said dilation balloon also having a preform length and an oriented length greater than said preform length, such that the ratio of the oriented length to the preform length is from about 1.5 to about 3.0;

said dilation balloon being fabricated from a material which imparts sufficient hoop strength and burst pressure to the balloon to enable it to perform its intended function, while being bio-compatible and having sufficient softness and pliability to prevent damage to non-target tissue with which it comes into contact;

(a.v) an inflatable fixation balloon mounted within the distal end of said outer catheter adjacent to said dilation balloon, a distance along the length of said outer catheter in a direction toward the proximal end of said outer catheter;

said fixation balloon having a preform diameter, and an oriented diameter greater than said preform diameter, such that the ratio of the oriented diameter to the preform diameter is from about 4.0 to about 7.0;

said fixation balloon also having a preform length and an oriented length greater than said preform length, such that the ratio of the oriented length to the preform length is from about 1.5 to about 3.0;

said fixation balloon being fabricated from a material which imparts sufficient hoop strength and burst pressure to the balloon to enable it to perform its intended function, while being bio-compatible and having sufficient softness and pliability to prevent damage to tissue with which it comes into contact;

(a.vi) temperature sensing means disposed in a manner selected from the group consisting of being carried in a lumen in said outer catheter and mounted on said dilation balloon, said temperature sensing means further including a temperature signal transmitting lead attached at one end thereof to said temperature sensing means, said lead passing through a lumen in said outer catheter provided therefor, and exiting from said proximal end of said outer catheter, at which an opposite end of said lead is connected to means for indicating temperature readings measured by said temperature sensing means; and

(a.vii) at least one fluid for inflating said dilation balloon and said fixation balloon, said at least one fluid for inflating said dilation balloon and said fixation balloon being carried into said dilation balloon and said fixation balloon through at least one inlet lumen in said outer catheter and out of said dilation balloon and said fixation balloon through at least one outlet lumen in said outer catheter;

(b) advancing said outer catheter through said lumen of the patient such that the distal end thereof is located in said lumen of the patient in the vicinity of said target tissue to be treated;

(c) inflating the fixation balloon to hold said outer catheter in position;

(d) inflating the dilation balloon to accomplish at least one of the functions of dilating said lumen of the patient in the vicinity of said target tissue to relieve any constriction therein and compressing tissue in order to restrict blood flow to said tissue during hyperthermal treatment, thereby reducing the heat sink effect of blood-supplied tissue which absorbs hyperthermal energy applied thereto, thereby enabling both greater uniformity of heating of selected target tissue and a reduction in the amount of power required to supply an effective amount of hyperthermal energy to said selected target tissue in order to produce hyperthermal effects therein;

(e) supplying energy to the heating means in order to raise the temperature of the selected target tissue and produce hyperthermal effects therein;

(f) circulating a coolant fluid through the lumen in the outer catheter provided therefor and through the dilation and fixation balloons in order to accomplish at least one of the functions of cooling surrounding tissue, and preventing overheating of the surface of the heating means;

(g) monitoring the temperature of at least one of the target tissue, surrounding non-diseased tissue, and the outlet temperature of the coolant fluid during hyperthermal treatment in order to ensure accomplishment of at least one of attaining a sufficiently high temperature in the target tissue in order to produce a hyperthermally induced changes in the cells thereof, to prevent the attainment of a cell damaging hyperthermal temperature in surrounding, non-target tissue, and to prevent overheating of the heating means and attain an optimum level of energy consumption;

(h) controlling the amount of energy supplied to the heating means in response to temperature measurements;

(i) terminating application of hyperthermal energy to said diseased target tissue after a sufficient time to produce therapeutic results;

(j) terminating the circulation of the coolant fluid through the outer catheter, the dilation balloon and the fixation balloon;

(k) deflating the dilation balloon;

(l) deflating the fixation balloon; and

(m) withdrawing the apparatus from the lumen of the patient.

2. The method according to claim 1, adapted for use in the treatment of diseases of the prostate, wherein said lumen of a patient is the male urethra;

said target tissue is diseased prostatic tissue;

said lumen of the patient in the vicinity of said target tissue is at least one of the prostatic urethra and the bladder neck;

inflation of said fixation balloon further prevents dilation of the external sphincter of the patient; and

said surrounding tissue cooled by circulation of said coolant fluid includes the urothelium and the external sphincter.

3. The method according to claim 2 wherein both the prostatic urethra and bladder neck are simultaneously dilated and selected diseased target tissue is hyperthermally heated.

4. A method for protecting the external sphincter against thermal damage during hyperthermal treatment of the prostate according to the method of claim 2, said method for protecting the external sphincter comprising:

positioning said fixation balloon of the apparatus on the proximal side of said external sphincter;

positioning said dilation balloon of the apparatus on the distal side of said external sphincter;

circulating said inflation fluid, with said inflation fluid also being a coolant, through said fixation balloon and said dilation balloon to thereby inflate said fixation balloon and said dilation balloon, and simultaneously cool an outer surface of each of said fixation balloon and said dilation balloon;

such that when said fixation balloon and said dilation balloon are inflated, at least a portion of said outer surface of said fixation balloon is in contact with at least a portion of said external sphincter on its proximal side, and at least a portion of said outer surface of said dilation balloon is in contact with at least a portion of said external sphincter on its distal side;

and further such that said fluid being circulated through each of said fixation balloon and said dilation balloon causes a cooling of said portions of said external sphincter, which are adjacent on its proximal and distal sides, respectively, to said portions of said outer surfaces of said fixation balloon and said dilation balloon.

5. The method according to claim 1 wherein the apparatus further comprises suction means detachably coupled to a port in the outer catheter cooperating with the lumen for fluid drainage provided therein, further comprising the step, performed between steps (e) and (i) of:

(e'"'"') utilizing the suction means to evacuate at least one fluid selected from the group consisting of blood, urine, and extracellular fluids through the drainage lumen in the outer catheter during hyperthermal treatment.

6. The method according to claim 1 wherein steps (e) through (h) inclusive are performed continuously for a specified period of time and substantially simultaneously with one another.

7. An apparatus for treatment of conditions in which it is desired to simultaneously hyperthermally treat diseased tissue in a patient and dilate a lumen of a patient which is being compressed and obstructed by diseased target tissue and/or surrounding tissue, said apparatus comprising:

(a) an outer catheter having a distal end, a proximal end having a plurality of ports therein, and a plurality of lumens situated through said outer catheter, said lumens including a lumen adapted for carrying heating means, inlet and outlet lumens respectively adapted for carrying a fluid into and out of at least one of an inflatable dilation balloon and an inflatable fixation balloon, said fluid being for the inflation of said balloons and alternatively also for acting as a coolant; and

up to one or more separate lumens adapted for performing one or more of the functions of carrying temperature sensing means;

circulating a coolant fluid through the outer catheter when said fluid for the inflation of said dilation and fixation balloons is not also a coolant;

carrying catheter guiding means; and

for drainage of fluid;

such that there is a corresponding portion of said proximal end of said outer catheter which cooperates with each lumen in said outer catheter;

(b) an inner catheter member, mounted in said outer catheter, and having a distal end, a proximal end, and a plurality of lumens therethrough;

(c) heating means, axially mounted at said distal end of said inner catheter, and extending within one of said plurality of lumens in said inner catheter member provided therefor, said heating means being for applying energy to selected diseased target tissue to produce hyperthermal effects therein, thereby causing a therapeutic alteration of cells in said target tissue;

(d) an inflatable dilation balloon mounted at the distal end of the outer catheter for accomplishing at least one of the functions of enlarging an obstructed lumen in the vicinity of said target tissue by compressing obstructive tissue, and restricting blood flow to at least one of said target tissue and to non-target tissue in the vicinity of said target tissue, in order to reduce the energy absorbing heat sink effect produced by blood-enriched tissue, thereby causing a more complete and more uniform absorption of energy by said target tissue;

said dilation balloon having a preform diameter, and an oriented diameter greater than said preform diameter, such that the ratio of the oriented diameter to the preform diameter is from about 4.0 to about 7.0;

said dilation balloon also having a preform length, such that the ratio of the oriented length to the preform length is from about 1.5 to about 3.0;

said dilation balloon being fabricated from a material which imparts sufficient hoop strength and burst pressure to the balloon to enable it to perform its intended function, while being bio-compatible and having sufficient softness and pliability to prevent damage to non-target tissue with which it comes into contact;

(e) an inflatable fixation balloon mounted within the distal end of said outer catheter adjacent to said dilation balloon, a distance along the length of said outer catheter in a direction toward the proximal end of said outer catheter;

said fixation balloon having a preform diameter, and an oriented diameter greater than said preform diameter, such that the ratio of the oriented diameter to the preform diameter is from about 4.0 to about 7.0;

said fixation balloon also having a preform length and an oriented length greater than said preform length, such that the ratio of the oriented length to the preform length is from about 1.5 to about 3.0;

said fixation balloon being fabricated from a material which imparts sufficient hoop strength and burst pressure to the balloon to enable it to perform its intended function, while being bio-compatible and having sufficient softness and pliability to prevent damage to tissue with which it comes into contact;

(f) temperature sensing means disposed in a manner selected from the group consisting of;

being carried in a lumen in said outer catheter; and

mounted on said dilation balloon, said temperature sensing means further including a temperature signal transmitting lead attached at one end thereof to said temperature sensing means, and at an opposite end thereof to means for indicating temperature readings measured by said temperature sensing means; and

(g) at least one fluid for inflating said dilation balloon and said fixation balloon, said at least one fluid for inflating said dilation balloon and said fixation balloon being carried into said dilation balloon and said fixation balloon through at least one inlet lumen in said outer catheter and out of said dilation balloon and said fixation balloon through at least one outlet lumen in said outer catheter.

8. The apparatus according to claim 7 wherein said heating means is selected from the group consisting of a microwave energy transmitting antenna and a radio frequency (RF) energy transmitting antenna.

9. The apparatus according to claim 8 wherein the heating means is a microwave energy transmitting antenna.

10. The apparatus according to claim 8 wherein at least one of said outer catheter and said dilation balloon is covered in selected parts with a material selected from the group consisting of microwave or frequency energy absorbing material, and a microwave or radio frequency energy reflecting material, in order to attenuate microwave or radio frequency energy radiated from said heating means in directions corresponding to those selectively covered parts of said at least one of said outer catheter and said dilation balloon to prevent the temperature in non-target tissue from reaching a damaging level.

11. The apparatus according to claim 7 wherein at least one of said plurality of lumens of said inner catheter member is a coolant lumen surrounding said lumen for said heating means.

12. The apparatus according to claim 11 wherein said inner catheter member has at least one lumen for inflow of coolant and at least one lumen for outflow of coolant, said at least one lumen for inflow of coolant communicating with said at least one lumen for outflow of coolant in at least one location at said distal end of said inner catheter member, to enable a circulation of coolant through said apparatus.

13. The apparatus according to claim 11 wherein said lumen for said heating means and said coolant lumen are the same.

14. The apparatus according to claim 7 wherein said dilation balloon and said fixation balloon are preformed together in a single-piece unit having a collar of specified length interspersed between and connecting said balloons.

15. The apparatus according to claim 7 wherein said temperature sensing means is selected from the group consisting of a thermocouple, a thermistor and a fiber-optic temperature sensor.

16. The apparatus according to claim 15 wherein when said temperature sensing means is a thermocouple, said thermocouple has a heat-conducting metallic element attached to at least a portion of the inflated outer surface area of said dilation balloon.

17. The apparatus according to claim 7 wherein said fixation balloon and said dilation balloon are attached to said outer catheter by bonding thereto.

18. The apparatus according to claim 7 wherein said fixation balloon and said dilation balloon are fabricated from a material selected from the group consisting of polyethylene, polyvinyl chloride, polyester, polyurethane, polyether ether ketone and a silicone elastomer.

19. The apparatus according to claim 18 wherein the material is low density polyethylene.

20. The apparatus according to claim 7 further comprising guidance means mounted in said outer catheter, for guiding said apparatus during its emplacement in said lumen of said patient, which is being compressed and obstructed, and is to be dilated.

21. The apparatus according to claim 20 wherein said guidance means is a guidewire situated in a lumen in said outer catheter provided therefor.

22. The apparatus according to claim 7 wherein said plurality of lumens in said outer catheter are situated axially through said outer catheter;

and said plurality of lumens in said inner catheter member are situated axially through said inner catheter member.

23. The apparatus according to claim 7 wherein said outer catheter is flexible.

24. The apparatus according to claim 7 further comprising suction means detachably coupled to a port in said outer catheter cooperating with a lumen for fluid drainage provided in said outer catheter.

25. The apparatus according to claim 7 wherein said lumen for said heating means is centrally located in said inner catheter member.

26. The apparatus according to claim 7 wherein said inner catheter member is independently slidably mounted in said outer catheter.

27. The apparatus according to claim 7, wherein the outer catheter is formed in a plurality of interconnecting and interlocking pieces.

28. The apparatus according to claim 27 wherein the outer catheter is formed of three interconnecting and interlocking pieces.

29. The apparatus according to claim 7 wherein said lumen for said heating means is asymmetrically located in said inner catheter member.

30. An apparatus for treatment of conditions in which it is desired to simultaneously hyperthermally treat diseased target tissue in a patient and dilate a lumen of a patient which is being compressed and obstructed by diseased target tissue and/or surrounding tissue, said apparatus having an overall proximal end and an overall distal end, with said apparatus comprising:

(a) an outer catheter having a distal end, a proximal end having a plurality of ports therein, and a plurality of lumens situated through said outer catheter, said lumens including a lumen adapted for carrying heating means, lumens adapted for carrying a fluid into and out of at least one of an inflatable dilation balloon and an inflatable fixation balloon, said fluid being for the inflation of said balloons and alternatively also for acting as a coolant; and

up to one or more separate lumens adapted for performing one or more of the functions of carrying temperature sensing means;

circulating a coolant fluid through the outer catheter when said fluid for the inflation of said dilation and fixation balloons is not also a coolant;

carrying catheter guiding means; and

for drainage of fluid;

such that there is a corresponding port in said proximal end of said outer catheter which cooperates with each lumen in said outer catheter, and further such that said outer catheter is fabricated in a plurality of interconnectable subsections, including at least a first subsection and a last subsection, and up to a plurality of intermediate subsections, with each subsection having a proximal end and a distal end, such that said proximal end of said first subsection is situated at said overall proximal end of said apparatus, said distal end of said last subsection is situated at said overall distal end of said apparatus; and

said proximal end of any of said plurality of intermediate subsections is in communication with said distal end of another one of said subsections to which it is immediately adjoining, beginning with said distal end of said first subsection; and

said distal end of any of said plurality of intermediate subsections is in communication with said proximal end of another one of said subsections to which it is immediately adjoining, ending with said proximal end of said last subsection; and

further such that when there are no intermediate subsections, said distal end of said first subsection is in communication with said proximal end of said last subsection;

with said subsections being configured such that while the internal path of lumens through any subsection may be the same as or different from the internal path of lumens through other subsections with which it is in communication, each said subsection is fabricated to have a configuration of lumens at its said proximal end and its said distal end which is identical to the configuration of lumens at the proximal end and the distal end of each other subsection, so that each subsection is interchangeable with and interconnectable to one another;

(b) heating means, axially mounted within the distal end of the outer catheter in the lumen provided therefor, for applying energy to selected diseased target tissue to produce hyperthermal effects therein, thereby causing a therapeutic alteration of cells in said target tissue;

(c) an inflatable dilation balloon mounted at the distal end of the outer catheter for accomplishing at least one of the functions of enlarging an obstructed lumen in the vicinity of said target tissue by compressing obstructive tissue, and restricting blood flow to at least one of said target tissue and to non-target tissue in the vicinity of said target tissue, in order to reduce the energy absorbing heat sink effect produced by blood-enriched tissue, thereby causing a more complete and more uniform absorption of energy by said target tissue;

said dilation balloon having a preform diameter, and an oriented diameter greater than said preform diameter, such that the ratio of the oriented diameter to the preform diameter is from about 4.0 to about 7.0;

said dilation balloon also having a preform length and an oriented length greater than said preform length, such that the ratio of the oriented length to the preform length is from about 1.5 to about 3.0;

said dilation balloon being fabricated from a material which imparts sufficient hoop strength and burst pressure to the balloon to enable it to perform its intended function, while being bio-compatible and having sufficient softness and pliability to prevent damage to non-target tissue with which it comes into contact;

(d) an inflatable fixation balloon mounted within the distal end of said outer catheter adjacent to said dilation balloon, a distance along the length of said outer catheter in a direction toward the proximal end of said outer catheter;

said fixation balloon having a preform diameter, and an oriented diameter greater than said preform diameter, such that the ratio of the oriented diameter to the preform diameter is from about 4.0 to about 7.0;

said fixation balloon also having a preform length and an oriented length greater than said preform length, such that the ratio of the oriented length to the preform length is from about 1.5 to about 3.0;

said fixation balloon being fabricated from a material which imparts sufficient hoop strength and burst pressure to the balloon to enable it to perform its intended function, while being bio-compatible and having sufficient softness and pliability to prevent damage to tissue with which it comes into contact;

(e) temperature sensing means disposed in a manner selected from the group consisting of;

being carried in a lumen in said outer catheter; and

mounted on said dilation balloon

said temperature sensing means further including a temperature signal transmitting lead attached at one end thereof to said temperature sensing means, and at an opposite and thereof to means for indicating temperature readings measured by said temperature sensing means; and

(f) at least one fluid for inflating said dilation balloon and said fixation balloon, said at least one fluid for inflating said dilation balloon and said fixation balloon being carried into said dilation balloon and said fixation balloon through at least one inlet lumen in said outer catheter and out of said dilation balloon and said fixation balloon through at least one outlet lumen in said outer catheter, such that said at least one inlet lumen of said outer catheter and said at least one outlet lumen of said outer catheter each constitute at least one of said plurality of lumens situated through said outer catheter.

31. The apparatus according to claim 30 wherein said at least one inlet lumen is a single inlet lumen having a first opening therein which communicates with said dilation balloon, a second opening therein which communicates with said fixation balloon, and an inlet port at said proximal end of said outer catheter;

and

said at least one outlet lumen is a single outlet lumen having a first opening therein which communicates with said dilation balloon, a second opening therein which communicates with said fixation balloon, and an outlet port at said proximal end of said outer catheter;

such that there is one said inflation fluid which is introduced through said inlet port into said inlet lumen and into said dilation balloon and said fixation balloon through said first and second openings therein to inflate both said dilation balloon and said fixation balloon, and

further such that both said dilation balloon and said fixation balloon are subsequently deflated by withdrawing said fluid through said first and second openings in said outlet lumen and out said outlet port of said outlet lumen.

32. The apparatus according to claim 31 wherein there is a valve means in said single inlet lumen situated between said first opening therein communicating with said fixation balloon and said second opening therein communicating with said dilation balloon, such that said valve means is initially maintained in a first position wherein it closes said single inlet lumen while fluid is first introduced into said single inlet lumen, and remains closed until said fixation balloon is fully inflated, whereupon, said valve means is openable to allow fluid to flow into and inflate said dilation balloon.

33. The apparatus according to claim 31 wherein said fluid used to inflate said dilation balloon are fixation balloon is at a temperature below the ambient temperature of its surroundings to thereby act as a coolant by absorbing heat transferred to it from its surroundings.

34. The apparatus according to claim 33 wherein after both said fixation balloon and said dilation balloon are inflated, an amount of fluid is withdrawn through said outlet lumen while an equal amount of fluid simultaneously enters said inlet lumen so that said fixation balloon and said dilation balloon are maintained in an inflated state, while a steady state circulation of fluid, acting as a coolant, is maintained therethrough.