CA2354587A1 - Method of controlling thermal therapy - Google Patents

Method of controlling thermal therapy Download PDF

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Publication number
CA2354587A1
CA2354587A1 CA002354587A CA2354587A CA2354587A1 CA 2354587 A1 CA2354587 A1 CA 2354587A1 CA 002354587 A CA002354587 A CA 002354587A CA 2354587 A CA2354587 A CA 2354587A CA 2354587 A1 CA2354587 A1 CA 2354587A1
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Canada
Prior art keywords
temperature
coolant
microwave antenna
predetermined
set point
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Abandoned
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CA002354587A
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French (fr)
Inventor
Thayne R. Larson
James E. Burgett
Jonathan L. Flachman
Eric N. Rudie
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Urologix Inc
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Individual
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Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B18/18Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves
    • A61B18/1815Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves using microwaves
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00Surgical instruments, devices or methods, e.g. tourniquets
    • A61B2017/00017Electrical control of surgical instruments
    • A61B2017/00022Sensing or detecting at the treatment site
    • A61B2017/00084Temperature
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/00234Surgical instruments, devices or methods, e.g. tourniquets for minimally invasive surgery
    • A61B2017/00238Type of minimally invasive operation
    • A61B2017/00274Prostate operation, e.g. prostatectomy, turp, bhp treatment
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00005Cooling or heating of the probe or tissue immediately surrounding the probe
    • A61B2018/00011Cooling or heating of the probe or tissue immediately surrounding the probe with fluids
    • A61B2018/00023Cooling or heating of the probe or tissue immediately surrounding the probe with fluids closed, i.e. without wound contact by the fluid
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00315Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body for treatment of particular body parts
    • A61B2018/00547Prostate

Abstract

A thermal therapy method includes inserting a microwave antenna containing applicator (27) into a body cavity such as a urethra (10) adjacent a targete d tissue region such as a prostate (14), energizing the microwave antenna (30) , circulating coolant between the microwave antenna, and a wall of the body cavity. The therapy is controlled by decreasing a temperature of the coolant , and continually adjusting coolant temperature based on other parameters. The applicator is maintained at a predetermined temperature set point by adjusti ng a power level provided to the microwave antenna. In one embodiment involving treatment of the prostate, rectal temperature is monitored, and upon sensing a rectal temperature that exceeds a predetermined threshold, the temperature o f the coolant is increased to force a reduction in power provided to the microwave antenna to maintain the applicator at the predetermined temperatur e set point.

Description

METHOD OF CONTROLLING THERMAL THERAPY
BACKGROUND OF THE INVENTION
The present invention relates to a method for treating tissue. In particular, the present invention relates to a method of 5 controlling thermal therapy of tissue such as the prostate to enhance treatment effectiveness with minimal treatment time.
The prostate gland is a complex, chestnut-shaped organ which encircles the urethra immediately below the bladder. Nearly one third of the prostate tissue anterior to the urethra consists of 10 fibromuscular tissue that is anatomically and functionally related to the urethra and the bladder. The remaining two thirds of the prostate is generally posterior to the urethra and is comprised of glandular tissue.
The portion of the urethra extending through the prostate (i.e., the prostatic urethra) includes a proximal segment, which communicates 15 with the bladder, and a distal segment, which extends at an angle relative to the proximal segment by the verumontanum.
Although a relatively small organ, the prostate is the most frequently diseased of all internal organs and is often the site of a common affliction among older men, benign prostatic hyperplasia 20 (BPH), as well as a more serious affliction, cancer. BPH is a nonmalignant, bilateral expansion of prostate tissue occurring mainly in the transition zone of the prostate adjacent to the proximal segment of the prostatic urethra. As this tissue grows in volume, it encroaches on the urethra extending into the region of the bladder neck at the base of 25 the bladder. Left untreated, BPH causes obstruction of the urethra which usually results in increased urinary frequency, urgency, incontinence, nocturia and slow or interrupted urinary stream. BPH may also result in more severe complications, such as urinary tract infection, acute urinary retention, hydronephrosis and uraemia.
30 Benign prostatic hyperplasia (BPH) may be treated using transurethral thermal therapy as described in further detail in U.S.
Patent 5,620,480 entitled METHOD FOR TREATING BENIGN
PROSTATIC HYPERPLASIA WITH THERMAL THERAPY and in U.S.
Patent 5,575,811 entitled BENIGN PROSTATIC HYPERPLASIA
TREATMENT CATHETER WITH URETHRAL COOLI NG, both of which are hereby incorporated by reference. During transurethral thermal therapy, the transition zone of the prostate is heated to necrose the tumorous tissue that encroaches on the urethra. Transurethral thermal therapy is administered by use of a microwave antenna-containing catheter which includes a multi-lumen shaft. The catheter is positioned in the urethra with the microwave antenna located adjacent to the hyperplastic prostatic tissue. Energization of the microwave antenna causes the antenna to emit electromagnetic energy which heats tissue within the prostate. A cooling fluid is circulated through the catheter to preserve tissue such as the urethral wall between the microwave antenna and the target tissue of the prostate.
The primary goal of. transurethral thermal therapy is to necrose prostate tissue while preserving 'adjacent healthy tissue. It is also preferable to achieve this goal in as short of a time as is possible, consistent with the patient's level of tolerance and comfort. In addition, it is important that the rectum be preserved from unduly high temperatures, since it is susceptible to thermal damage. There is an ongoing need in the art for a method of controlling thermal therapy that reduces treatment time and enhances effectiveness consistent with all of these parameters.
SUMMARY OF THE INVENTION
The present invention is a method of treating tissue with heat from an adjacent body cavity, such as treating a prostate with heat delivered from a urethra. A microwave antenna-containing applicator is inserted into the body cavity adjacent the targeted tissue region. The microwave antenna in the applicator is energized, thereby delivering electromagnetic energy to the targeted tissue region, and coolant is circulated between the microwave antenna and a wall of the body cavity.
A temperature of the coolant circulated is decreased, and coolant WO 00/337b7 PCT/US99/29381 temperature is continually adjusted based on other parameters. For example, where the targeted tissue region is the prostate adjacent the urethra, rectal temperature is monitored and, upon sensing a rectal temperature that exceeds a predetermined threshold, coolant 5 temperature is increased. Coolant temperature may also be adjusted based on patient comfort indicators. The applicator is maintained at a predetermined temperature set point by adjusting a power level provided to the microwave antenna.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical section view of a male pelvic region showing the urinary organs affected by benign prostatic hyperplasia.
FIG. 2 is an enlarged view of the male pelvic region of FIG.
1 showing a urethral catheter positioned in the prostatic region.
FIGS. 3A .and 3B are graphs illustrating basic tissue temperature/depth curves at . different. power levels and coolant temperatures during thermal therapy.
FIGS. 4A and 4B are block diagrams illustrating the thermal therapy control methods according to two embodiments of the present invention.
FIG. 5A is a graph illustrating temperatures achieved during a thermal therapy treatment session according to one variation of the control method of the present invention.
FIG. 5B is a graph illustrating temperatures achieved during a thermal therapy treatment session according to a second variation of the control method of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a vertical sectional view of a male pelvic region showing the effect benign prostatic hyperplasia (BPH) has on the urinary organs. Urethra 10 is a duct leading from.bladder 12, through prostate 14 and out orifice 16 of penis end 18. Benign tumorous tissue growth within prostate 14 around urethra 10 causes constriction 20 of urethra 10, which interrupts the flow of urine from neck 22 of bladder 12 to WO 00/33767 PCTNS99/293$I
orifice 16. The tumorous tissue of prostate 14 which encroaches urethra 10 and causes constriction 20 can be effectively removed by heating and necrosing the encroaching tumorous tissue. Ideally, periurethral tumorous tissue of prostate 14 anterior and lateral to urethra 10 is heated and necrosed to avoid unnecessary and undesirous damage to urethra 10 and to adjacent healthy tissues, such as ejaculatory duct 24 and rectum 26. A selective heating of benign tumorous tissue of prostate 14 (transurethral thermal therapy) may be achieved by utilizing a microwave antenna-containing catheter such as is shown in U.S. Patent 5,620,480 or U.S. Patent 5,575,811, which have been incorporated herein by reference.
FIG. 2 shows an enlarged view of the male pelvic region of FIG. 1 with a catheter 27 simplistically shown properly positioned within urethra 10: While the particular structure of catheter 27 may vary and a number of.lumens.may.be provided therein, catheter 27 typically includes transmission line 28 connected to microwave antenna 30 for emitting microwave energy to prostate 14. Cooling fluid is circulated along paths 32 between microwave antenna 30 and the walls 36 of urethra 10, so as to conductively cool the tissue of urethra 10 when microwave antenna 30 is energized to radiate microwave energy to prostate 14. Catheter 27 may be secured within urethra 10 by retention balloon 34 located in bladder 12, for example. The temperature of the urethra may be detected by providing a temperature sensor on catheter 27 contacting urethral walls 36. In addition, the temperature of rectum 26 may be detected by inflating a balloon or providing another type of device in rectum 26 that includes a temperature sensor in contact with the rectal wall, such as is disclosed in U.S. Patent 5,792,070 entitled RECTAL THERMOSENSING UNIT, which is hereby incorporated by reference.
FIGS. 3A and 3B are graphs illustrating basic tissue temperature/depth curves at different power levels and coolant temperatures during thermal therapy, and demonstrating the basic _5-principles ofthe present invention. Particularly, FIG. 3A illustrates tissue temperature/depth curves for a treatment session where catheter temperature is held at a predetermined value {such as 40°C), and FIG.
3B illustrates tissue temperatureldepth curves for a treatment session 5 where a certain depth of tissue around the catheter is held at a predetermined value (such as 40°C). The vertical axes of FIGS. 3A and 3B represent the temperature of tissue, and the horizontal axes represent the depth from the catheter/urethra of that tissue. Therefore, a depth of zero represents the urethral wall.
10 Each of the curves shown in FIG. 3A represents a different coolant temperature and microwave power condition, with the constant criteria for each curve being that the temperature of the catheter (at depth=0) is .maintained at a steady-state temperature such as 40°C.
Curve 40 represents a situation where microwave power is zero and 15 coolant temperature is equal to the.steady-state catheter temperature {e.g., 40°C), .curve 42 represents a situation where the microwave power is high and coolant temperature is at a minimum (such as 8°C, for illustrative purposes) and the curves between curve 40 and curve 42 represent situations where the microwave power is between zero and 20 the high value, and the coolant temperature is between the steady-state cathetertemperature (e.g., 40°C) and the minimum coolanttemperature (e.g., 8°C). Each curve is labeled according to the relative coolant temperature {tc) and power level (p), so that curve 40 represents the highest coolant temperature (tc,) and the lowest power (p,) and curve 42 25 represents the lowest coolant temperature (t~,) and the highest power level (p,}, wherein each curve is predicated on the condition that catheter temperature is maintained at a steady-state temperature such as 40°C. The particularvalues of the minimum coolant temperature and corresponding power level depend on the structure and characteristics 30 of the treatment catheter employed, and it should be understood that the exemplary values provided herein refer only to one particular catheter structure; other values are appropriate for different catheter structures, while still practicing the present invention. As can be seen from the curves shown in FIG. 3A, when the catheter temperature is maintained at a steady-state temperature such as 40°C, decreased coolant temperature results in deeper heating of tissue in the prostate 5 due to the increased power level required to maintain the catheter at the steady-state temperature. This may result in a greater depth of necrosis caused by heating the tissue above a particular threshold temperature.
Each of the curves shown in FIG. 3B also represent a different coolant temperature and microwave power condition, with the 10 constant criteria for each curve being that the temperature of tissue at a depth of interest, defining a zone of protection from the outer surface of the catheter to that tissue depth (such as 1 millimeter, for example), is maintained at a steady-state temperature such as 40°C. Curve 44 represents a situation where microwave power is slightly greater than 15 zero and coolant temperature is equal to a aemperature slightly greater than the steady-state tissue temperature (e.g., 40°C), which is slightly different from the power and coolant temperature shown in curve 40 (FIG. 3A) where the catheter rather than a depth of tissue was maintained at a steady-state temperature such as 40°C. Curve 46 20 represents a situation where the microwave power is high and coolant temperature is at a minimum (such as 8°C, for illustrative purposes) and the curves between curve 44 and curve 46 represent situations where the microwave power is between zero and the high value, and the coolant temperature is between the steady-state tissue temperature 25 (e.g., 40°C) and the minimum coolant temperature (e.g., 8°C).
Each curve is labeled according to the relative coolant temperature (t~) and power level (p), so that curve 44 represents the highest coolant temperature (t~,) and the lowest power (p,) and curve 46 represents the lowest coolant temperature (tc,) and the highest power level (p,), 30 wherein each curve is predicated on the condition that tissue temperature is maintained at a steady-state temperature such as 40°C.
The particular values of the minimum coolant temperature and corresponding power level depend on the structure and characteristics of the treatment catheter employed, and it should be understood that the exemplary values provided herein refer only to one particular catheter structure; other values are appropriate for different catheter 5 structures, while still practicing the present invention. As can be seen from the curves shown in FIG. 3, when the tissue temperature at a depth of interest is maintained at a steady-state temperature such as 40°C, decreased coolanttemperature results in deeper heating oftissue in the prostate due to the increased power level required to maintain the 10 tissue at the steady-state temperature. This may result in a greater depth of necrosis caused by heating the prostate tissue above a particular threshold temperature.
In the thermal therapy curves depicted in FIGS. 3A and 3B, if coolant temperature is continually decreased and microwave 15 power is correspondingly continually increased to maintain the catheter or tissue temperature at the steady-state temperature or at a set point temperature while initially vamping up the catheter/tissue temperature, temperatures at the depth of the rectum may become unacceptably high. In other words, high temperatures are achieved at too great of a 20 depth from the catheter/urethra. Therefore, in a preferred method of controlling thermal therapy, rectal temperature is utilized as a parameter for controlling the coolant temperature (and the catheter/tissue temperature set point, temporarily) to enable optimal therapy without thermally damaging the tissue of the rectum.
25 FIG. 4A is a block diagram illustrating a complete thermal therapy control method according to a first embodiment of the present invention, utilizing the principles and parameters discussed above with respect to FIG. 3A. To initialize the therapy, a physician enters inputs related to cathetertemperature at block 50 and inputs related to coolant 30 temperature at block 52. Specifically, a physician enters an initial ramp rate of catheter temperature (that is, how quickly and in what manner the catheter temperature is to increase from its initial temperature of _$_ approximately body temperature (37°C) to its final, steady-state temperature) and a steady-state catheter temperature. In addition, the physician enters a coolant temperature ramp rate (that is, how quickly and in what manner the coolant temperature is to decrease from its initial temperature to a targeted final temperature), an initial coolant temperature and a steady-state coolant temperature. The catheter temperature ramp rate and the coolant temperature ramp rate may comprise a ramping function, such that catheter temperature andlor coolant temperature increases or decreases exponentially, linearly, or according to some otherfunction that enhances the effectiveness of the therapy consistent with patient comfort concerns. The exact value and degree of physician contribution of these inputs will depend on experimental results of therapy in particular patients, and are set consistent with a desired patient comfort level. The actual format of physician input may also be simplified by an appropriate software program or other means, so that the physician enters only minimal data and the program calculates the therapy inputs from the data entered by the physician. The physician inputs are further explained graphically below with respect to FIGS. 5A and 5B.
From the cathetertemperature inputs entered at block 50, a catheter temperature profile is established at block 54. The catheter temperature profile represents a desired characteristic of catheter temperature at a particular time in the thermal therapy session, which may of course be adjusted by other parameters such as rectal temperature and patient comfort during the course of the therapy, as noted below. From the coolant temperature inputs entered at block 52, a coolant temperature profile is established at block 56. The coolant temperature profile also represents a desired characteristic of coolant temperature at a particular time in the thermal therapy session, which again may be adjusted by other parameters such as rectal temperature and patient comfort during the course of the therapy, as noted below.

_g_ The catheter temperature profile signal is passed on to adder/subtractor 58, which passes a modified catheter temperature set point signal on to Microwave Power Control block 60, which in one preferred embodiment is implemented as a 5 proportional/integral/differential {PID) control loop. PID control loops are algorithms known in the artfor controlling a process to achieve a desired output level. The power delivered to the microwave antenna 30 (FIG.
2) energizes the antenna to radiate electromagnetic energy, resulting in elevation of prostate tissue as represented by block 62. Power 10 delivered to the microwave antenna is continually adjusted to ensure that the catheter remains at the modified cathetertemperature set point;
therefore, Microwave Power Control block 60 is responsive to the measured catheter temperature at block 64 to adjust microwave power accordingly.
15 Elevation of prostate tissue temperature at block 62 causes a biological response in the tissue, which is represented by block 66. One response is increased blood perfusion in the tissue, which tends to conduct heat away from a particular portion of tissue and reduce the heating effect on the tissue. Also, when electromagnetic 20 energy is delivered to elevate the temperature of prostate tissue, the temperature of the rectum may also be increased. Rectal temperatures are therefore monitored during thermal therapy to ensure that the rectum is not thermally damaged by excessively high temperatures; the measured rectal temperature is represented by block 68. If rectal 25 temperature reaches a predetermined threshold, steps must be taken to reduce the temperature of the rectum so that it may be preserved. In an ideal situation, coolant temperature would be immediately increased (with microwave power correspondingly decreased to maintain catheter temperature at the desired set point) in response to high rectal 30 temperatures. However, in actuality, it may not be possible to instantaneously change the temperature of the coolant. Therefore, to safely ensure preservation of the rectum, according to one preferred -~ o-embodiment of the present invention, the cathetertemperature is initially reduced in response to high rectal temperatures by a catheter temperature modifier represented at block 70. The catheter temperature modifier is subtracted by adder/subtractor 58 from the desired catheter temperature provided by the catheter temperature profile to yield a modified catheter temperature set point, which is input to Microwave Power Control block 60. By reducing the catheter temperature set point immediately, with all other parameters remaining the same, the microwave powerwill be reduced and tissue temperatures will immediately decrease. For increasingly higher rectal temperatures, the catheter temperature set point is decreased by a greater amount.
In addition, a Coolant Temperature Control block 72 implements a PID
control loop, for example, to determine an increased temperature of the coolant. Comparator block 74 outputs the higher of the coolant temperature provided by the coolant temperature profile at block 56 and the coolanttemperature provided by Coolant Temperature Control block 72. In other words, the desired coolant temperature is determined by the coolant temperature profile at block 56 unless an excessively high rectal temperature causes a higher coolant temperature to be determined by Coolant Temperature Control block 72. The desired coolant temperature is input to CoolerlHeater Control block 76 along with the measured coolant temperature at block 78, and Cooler/Heater Control block 76 implements a PID control loop, for example, to adjust coolant temperature and stabilize the coolant at the appropriate temperature. The actual coolant temperature affects the temperature of the catheter and temperature to which prostate tissue and the rectum are elevated, which is represented by the line from Cooler/Heater Control block 76 to the tissue temperature elevation shown at block 62.
Finally, as the rectal temperature returns to a value below the threshold, the catheter temperature modifier is reduced to zero, and the catheter temperature returns to the value provided by the catheter temperature profile at block 54, with the system stabilizing at the higher coolant temperature. By implementing this control method, rectal temperatures (and prostate tissue temperatures) reach the highest attainable level without exceeding a threshold rectal temperature, while simultaneously maintaining the catheter temperature set point at the maximum desired 5 value consistent with patient comfort. It is somewhat counter intuitive that coolanttemperature should be increased in response to excessively high temperatures in the rectum, but it is nonetheless true where the catheter temperature is constrained to a predetermined steady-state value, since an increase in coolant temperature effectively forces a 10 reduction in power provided to the microwave antenna to maintain the catheter at the steady-state value. The method of the present invention therefore enhances the effectiveness and reduces the necessary treatment time of the therapy.
The thermal therapy controlled by the method of the 15 present invention must take into account the comfort level of the patient at various phases of the therapy. For example, the catheter temperature ramp rate or vamping function or the steady-state catheter temperature may potentially drive changes in power that may result in discomfort for the patient. Similarly, the coolant temperature ramp rate 20 or vamping function or other parameters may also result in power level changes that could potentially cause some patient discomfort. As the thermal therapy session progresses, a physician may adjust the therapy at any time in response to an indication of patient discomfort, represented by block 79. Patient discomfort may potentially occur as a 25 result of high absolute temperatures, or also as a result of high rates of change of temperatures, and therapy therefore is adjustable to change parameters related to both of these factors. The therapy parameter changes implemented by the physician (at blocks 50 and 52) are integrated into the therapy control method of the present invention to 30 reduce or eliminate the discomfort of the patient.
FIG. 4B is a block diagram illustrating a complete thermal therapy control method according to a second embodiment of the present invention, utilizing the principles and parameters discussed above with respect to FIG. 3B. The majority of the method shown in FIG. 4B is identical to that shown in FIG. 4A, with one principal modification. Instead of utilizing a catheter temperature set point as 5 shown in F1G. 4A, the modified method shown in FIG. 4B is concerned with a tissue temperature set point (that is, the temperature in tissue at some depth of interest from the catheter/urethra, defining a tissue protection zone). Therefore, to initialize the therapy, a physician enters an initial tissue temperature ramp rate/ramping function and a steady-10 state~tissue temperature at block 50b, in a manner substantially similar to that described with respect to block 50a of FIG. 4A. From the tissue temperature inputs entered at block 50b, a tissue temperature profile is established at block 54b, which represents a desired characteristic of tissue temperature at a particular time in the thermal therapy session, 15 which may of course be adjusted by other parameters such as rectal temperature and patient comfort during the course of the therapy, as noted below.
The tissue temperature profile signal is passed on to adder/subtractor 58, which passes a modified tissue temperature set 20 point signal on to Microwave Power Control block 60, which is implemented as described above with respect to FIG. 4A. The power delivered to microwave antenna 30 (FIG. 2) energizes the antenna to radiate electromagnetic energy, resulting in elevation of prostate tissue as represented by block 62. Power delivered to the microwave antenna 25 is continually adjusted to ensure that tissue at the depth of interest remains at the modified tissue temperature set point. In order to do so, Microwave Power Control block 60 must be responsive to tissue temperature. However, tissue temperature at a depth from the catheter/urethra typically cannot be measured directly without 30 penetrating the urethra. Therefore, in one embodiment of the present invention, catheter temperature is measured at block 64, and tissue temperature is calculated at block 65 based on the measured catheter temperature (block 64), the microwave power level (block 60) and ttie measured coolant temperature (block 78). Microwave Power Control block 60 is therefore responsive to the calculated tissue temperature at block 65 to adjust microwave power accordingly. fn an aitemative 5 embodiment, a temperature sensor may be positioned in the tissue by penetrating the urethra, or some other temperature sensing system for directly measuring tissue temperature may be implemented, in which case the measured tissue temperature would replace measured catheter temperature at block 64 of FIG. 4A, and there would be no 10 need to calculate tissue temperature.
Rectal temperatures are also monitored during thermal therapy to ensure that the rectum is not thermally damaged by excessively high temperatures; the measured rectal temperature is represented by block 68. If rectal temperature reaches a predetermined 15 threshold, steps must be taken to reduce the temperature of the rectum so that it may be preserved. As described above with respect to FIG.
4A, since coolant temperature may not be able to be instantaneously increased, the temperature set point is initially decreased to force microwave power to be immediately reduced. This tissue temperature 20 set point is reduced by the tissue temperature modifier represented at block 70b, which is subtracted by adder/subtractor 58 from the desired tissue temperature to yield a modified tissue temperature set point input to Microwave Power Control block 60. As also described above with respect to FIG. 4A, after coolant temperature is increased and rectal 25 temperature is returning to a value below the threshold, the tissue temperature modifier is reduced to zero, and the tissue temperature returns to the value provided by the tissue temperature profile at block 54b, with the system stabilizing at the higher coolant temperature.
FIG. 5A is a graph illustrating measured temperatures 30 achieved during an actual thermal therapy treatment session in a clinical trial according to one variation of the control method of the present invention. In the clinical trial, anesthesia was used to ensure that the patients remained comfortable, so the patient comfort adaptability of the present invention was not utilized in the trial. Curve 80 represents the temperature of the catheter inserted into the urethra of the patient.
Curve 82 represents the temperature of the coolant circulated between 5 the antenna in the catheter and the urethral wall; the small oscillations in curve 82 are due to the heating/cooling system utilized in the trial.
Curve 84 represents the microwave power level delivered to the antenna. Curve 88 represents the temperature of tissue at a depth of approximately 0.5 cm in the prostate surrounding the urethra.
10 Initially, power (curve 84) was ramped up quickly to raise the temperature of the catheter (curve 80} to approximately 40°C (the catheter temperature set point), with coolant temperature (curve 82} at an initial value of approximately 22°C. These characteristics correspond to the catheter temperature ramp rate and the initial coolant 15 temperature set by the physician at blocks 50a and 52 (FIG. 4A). The ramp rate and vamping function may vary as described above; the clinical trial shown in FIG. 5A utilized a unit step function, which increased catheter temperature to the steady-state value as quickly as the system capabilities permitted. Coolant temperature was then 20 reduced in step-wise increments, while the microwave power level was increased in tum to maintain the catheter temperature at the steady-state temperature such as 40°C (set by the physician in block 50a, FIG.
4A). The step-wise decrease in coolant temperature was set by the physician as the coolant temperature ramp rate (block 52, FIG. 4A);
25 again, the ramp rate and vamping function can vary as described above.
As a result, the temperature of prostate tissue (curve 88) increased in a corresponding step-wise mannerto the coolanttemperature decrease.
Coolant temperature finally reached a steady-state temperature, which again had been set by the physician at block 52, FIG. 4A. Also, 30 throughout the therapy, rectal temperature was monitored to ensure that temperatures do not exceed a predetermined threshold, to prevent WO 00/337b7 PGT/US99/29381 thermal damage to the rectum; no excessively high rectal temperatures were detected.
At a treatment time between 30 and 40 minutes, the catheter temperature set point (curve 80) was increased from 40°C to 5 42°C for experimental purposes. As expected, the increase in steady-state catheter temperature resulted in a corresponding increase in power (curve 84) and tissue temperature (curve 88), while the coolant temperature (curve 82) was kept constant.
Microwave powercurve 84, cathetertemperature curve 80 10 and tissue temperature curve 88 experience some oscillation at a treatment time between 40 and 50 minutes. These oscillations were due to a bladder spasm experienced by the patient at this time, which may occurfrom time to time during a thermal therapy treatment session.
During the bladder spasm, although catheter temperature oscillated 15 briefly, the control method of the present invention caused it to remain at a level approximately equal to or below the catheter temperature set point, and catheter temperature returned to the steady-state temperature automatically and stabilized with no outside intervention when the bladder spasm ceased.
20 FIG. 5B is a graph illustrating measured temperatures achieved during an actual thermal therapy treatment session in a clinical trial according to a second variation of the control method of the present invention. In the clinical trial, anesthesia was used to ensure that the patients remained comfortable, so the patient comfort adaptability of the 25 present invention was not utilized in the trial. Curve 90 represents the temperature of the catheter inserted into the urethra of the patient.
Curve 92 represents the temperature of the coolant circulated between the antenna in the catheter and the urethral wall. Curve 94 represents the microwave power level delivered to the antenna. Curve 98 30 represents the temperature of tissue at a depth of approximately 0.5 cm in the prostate surrounding the urethra.

WO 00/3376'7 PCTNS99/29381 Initially, power (curve 94) was tamped up quickly to raise the temperature of the catheter (curve 90) to approximately 40°C (the catheter temperature set point), with coolant temperature (curve 92) at an initial value of approximately 28°C. These characteristics 5 correspond to the catheter temperature ramp rate and the initial coolant temperature set by the physician at blocks 50a and 52 (FIG. 4A). The ramp rate and tamping function may vary as described above; the clinical trial shown in FIG. 5B utilized a unit step function, which increased catheter temperature to the steady-state value as quickly as 10 the system capabilities permitted. Coolant temperature was then reduced quickly, while the microwave power level was increased in turn to maintain the catheter temperature at the steady-state temperature such as 40°C (set by the physician in block 50a, FIG. 4A). The decrease in coolant temperature was set by the physician as the coolant 15 temperature ramp rate (block 52, FIG. 4A); the function utilized was a unit step function causing coolant to decrease in temperature as quickly as the heating/cooling system would allow, but again, the ramp rate and tamping function can vary as described above. As a result, the temperature of prostate tissue (curve 88) increased in a manner 20 corresponding to the coolant temperature decrease. Coolant temperature finally reached a steady-state temperature, which again had been set by the physician at block 52, FIG. 4A. Also, throughout the therapy, rectal temperature was monitored to ensure that temperatures do not exceed a predetermined threshold, to prevent 25 thermal damage to the rectum; no excessively high rectal temperatures were detected. As can be seen in FIG. 5B, tissue temperatures exceeding about 90% of the peak tissue temperature were obtained within about 10 minutes.
It should be understood that the particular temperatures 30 set and observed in the clinical trials illustrated by FIGS. 5A and 5B are exemplary, and the particular temperatures chosen and observed in practicing the present invention will vary depending on the patient's comfort level, the particular catheter structure utilized, and otherfactors.
The thermal therapy control method of the present invention is significantly different from prior art control methods, in that 5 the therapy is driven by controlling coolant temperature and making automatic corresponding adjustments to microwave power to maintain catheter or tissue temperature at a particular set point. In the absence of limiting parameters, coolant temperature is preferably as low as possible, so that microwave power is forced to correspondingly increase 10 to maintain cathetertemperature constant and tissue is therefore heated to maximum temperatures. Rectal temperature is one factor that limits the therapy, since the rectum must be preserved below a threshold temperature to avoid thermal damage. The control method of the present invention allows the thermal therapy system to be optimally 15 operated, with rectal temperatures as high as possible without thermally damaging the rectum and catheter temperatures maintained at a predetermined steady-state operating temperature. As a result, a precise depth of tissue necrosis is achievable with no physician intervention to control the therapy. Therapy times are also minimized, 20 since the control method of the present invention allows tissue temperatures to reach 90% of their maximum value within about 10 minutes, if tolerable by the patient, which is a significant improvement over the prior art.
The thermal therapy control method of the present 25 invention has been described primarily as it applies to treatment of a prostate from a urethra. However, the principles and methods of the present invention are likewise applicable to thermally treating other regions of tissue from adjacent body cavities. Preservation of adjacent organs may also be applicable, in a manner similar to the preservation 30 of the rectum described above with respect to one preferred embodiment of the invention.

Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.

Claims (32)

WHAT IS CLAIMED IS:
1. A thermal therapy method comprising:
inserting a microwave antenna-containing applicator into a body cavity adjacent a targeted tissue region;
energizing a microwave antenna in the applicator to deliver microwave energy to the targeted tissue region; and circulating coolant between the microwave antenna and a wall of the body cavity;
controlling a temperature of the coolant circulated between the microwave antenna and the wall of the body cavity according to a predetermined coolant temperature profile;
continually adjusting coolant temperature based on other parameters; and maintaining the applicator at a predetermined temperature set point by adjusting a power level provided to the microwave antenna in coordination with the coolant temperature.
2. The thermal therapy method of claim 1, wherein coolant temperature is adjusted based on patient comfort indicators.
3. The thermal therapy method of claim 1, wherein coolant temperature is initially pre-set to a minimum value.
4. The thermal therapy method of claim 1, wherein the step of adjusting coolant temperature based on other parameters comprises monitoring a temperature of an adjacent body organ.
5. The thermal therapy method of claim 4, wherein coolant temperature is continually adjusted to maintain a body organ temperature at a predetermined value, thereby forcing corresponding adjustment of the power level provided to the microwave antenna to maintain the applicator at the predetermined temperature set point.
6. The thermal therapy method of claim 5, further comprising the step of temporarily adjusting the applicator temperature set point upon detecting a predetermined body organ temperature profile.
7. The thermal therapy method of claim 4, wherein coolant temperature is increased in response to a body organ temperature greater than a predetermined threshold, thereby forcing a reduction in the power level provided to the microwave antenna to maintain the applicator at the predetermined temperature set point.
8. The thermal therapy method of claim 7, further comprising the step of temporarily decreasing the applicator temperature set point upon detecting a body organ temperature greater than the predetermined threshold.
9. The thermal therapy method of claim 1, wherein the body cavity is a urethra and the targeted tissue region is prostate tissue, and wherein the step of adjusting coolant temperature based on other parameters comprises monitoring rectal temperature and adjusting coolant temperature in response to a rectal temperature greater than a predetermined threshold, thereby forcing a corresponding adjustment of the power level provided to the microwave antenna to maintain the applicator at the predetermined temperature set point.
10. The thermal therapy method of claim 9, further comprising the step of temporarily adjusting the applicator temperature set point upon detecting a rectal temperature greater than the predetermined threshold.
11. A method of treating a prostate with heat via a urethra comprising:
inserting a microwave antenna-containing applicator into the urethra adjacent the prostate;
inserting a rectal temperature sensing probe into a rectum;

providing power to the microwave antenna while circulating coolant between the microwave antenna and a wall of the urethra;
decreasing a temperature of the coolant to a steady-state coolant temperature;
maintaining the applicator at a predetermined temperature set point by continually adjusting the power provided to the microwave antenna in coordination with the coolant temperature; and monitoring rectal temperature with the rectal temperature sensing probe and, upon sensing a predetermined rectal temperature profile, increasing the coolant temperature so as to force a reduction in power provided to the microwave antenna to maintain the applicator at the predetermined temperature set point.
12. The method of claim 11, wherein the predetermined temperature set point of the applicator and the steady-state coolant temperature are input by a physician.
13. The method of claim 11, wherein the predetermined temperature of the applicator is 40°C.
14. The method of claim 11, wherein a catheter temperature ramp rate, an initial coolant temperature and a coolant temperature ramp rate are input by a physician.
15. The method of claim 11, wherein the predetermined temperature of the applicator, the steady-state coolant temperature, a catheter temperature ramp rate, an initial coolant temperature and a coolant temperature ramp rate are adjustable in response to patient comfort indicators.
16. The method of claim 11, further comprising the step of temporarily decreasing the applicator temperature set point upon detecting the predetermined rectal temperature profile.
17. A thermal therapy control method comprising:
inserting a microwave antenna-containing applicator into the urethra adjacent the prostate; and providing power to the microwave antenna while circulating coolant between the microwave antenna and a wall of the urethra, wherein the power provided to the microwave antenna is automatically adjusted to maintain the applicator at a predetermined temperature set point.
18. The thermal therapy method of claim 17, further comprising:
inserting a rectal thermosensing probe into a rectum;
adjusting coolant temperature upon detecting a rectal temperature above a predetermined threshold; and maintaining the applicator at the predetermined temperature set point by automatically adjusting the power provided to the microwave antenna.
19. A thermal therapy method comprising:
inserting a microwave antenna-containing applicator into a urethra adjacent a prostate;
providing power to the microwave antenna while circulating coolant between the microwave antenna and a wall of the urethra; and controlling a temperature of the coolant and the power provided to the microwave antenna to achieve tissue temperatures in the prostate that are 90% of a peak temperature within about 10 minutes.
20. A thermal therapy method comprising:
inserting a microwave antenna-containing applicator into a body cavity adjacent a targeted tissue region;
energizing a microwave antenna in the applicator to deliver microwave energy to the targeted tissue region; and circulating coolant between the microwave antenna and a wall of the body cavity;
controlling a temperature of the coolant circulated between the microwave antenna and the wall of the body cavity according to a predetermined coolant temperature profile;
continually adjusting coolant temperature based on other parameters; and maintaining selected tissue at a predetermined depth from the wall of the body cavity at a predetermined temperature set point by adjusting a power level provided to the microwave antenna in coordination with the coolant temperature.
21. The thermal therapy method of claim 20, wherein coolant temperature is adjusted based on patient comfort indicators.
22. The thermal therapy method of claim 20, wherein the step of adjusting coolant temperature based on other parameters comprises monitoring a temperature of an adjacent body organ.
23. The thermal therapy method of claim 22, wherein coolant temperature is increased in response to a body organ temperature greater than a predetermined threshold, thereby forcing a reduction in the power level provided to the microwave antenna to maintain the selected tissue at the predetermined temperature set point.
24. The thermal therapy method of claim 23, further comprising the step of temporarily decreasing the selected tissue temperature set point upon detecting a body organ temperature greater than the predetermined threshold.
25. The thermal therapy method of claim 20, wherein the body cavity is a urethra and the targeted tissue region is prostate tissue, and wherein the step of adjusting coolant temperature based on other parameters comprises monitoring rectal temperature and increasing coolant temperature in response to a rectal temperature greater than a predetermined threshold, thereby forcing a reduction in the power level provided to the microwave. antenna to maintain the selected tissue at the predetermined temperature set point.
26. The thermal therapy method of claim 25, further comprising the step of temporarily decreasing the selected tissue temperature set point upon detecting a rectal temperature greater than the predetermined threshold.
27. A method of treating a prostate with heat via a urethra comprising:
inserting a microwave antenna-containing applicator into the urethra adjacent the prostate;
inserting a rectal temperature sensing probe into a rectum;
providing power to the microwave antenna while circulating coolant between the microwave antenna and a wall of the urethra;
decreasing a temperature of the coolant to a steady-state coolant temperature;
maintaining selected tissue at a predetermined depth from the wall of the urethra at a predetermined temperature set point by continually adjusting the power provided to the microwave antenna in coordination with the coolant temperature; and monitoring rectal temperature with the rectal temperature sensing probe and, upon sensing a predetermined rectal temperature profile, increasing the coolant temperature so as to force a reduction in power provided to the microwave antenna to maintain the selected tissue at the predetermined temperature set point.
28. The method of claim 27, wherein the predetermined temperature set point of the selected tissue and the steady-state coolant temperature are input by a physician.
29. The method of claim 27, wherein the predetermined temperature set point of the selected tissue is 40°C.
30. The method of claim 27, wherein a catheter temperature ramp rate, an initial coolant temperature and a coolant temperature ramp rate are input by a physician.
31. The method of claim 27, wherein the predetermined temperature set point of the selected tissue, the steady-state coolant temperature, a catheter temperature ramp rate, an initial coolant temperature and a coolant temperature ramp rate are adjustable in response to patient comfort indicators.
32. The method of claim 27, further comprising the step of temporarily decreasing the selected tissue temperature set point upon detecting the predetermined rectal temperature profile.
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US09/210,033 US6122551A (en) 1998-12-11 1998-12-11 Method of controlling thermal therapy
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Families Citing this family (107)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6216703B1 (en) * 1998-05-08 2001-04-17 Thermatrx, Inc. Therapeutic prostatic thermotherapy
US6620189B1 (en) * 2000-02-28 2003-09-16 Radiant Medical, Inc. Method and system for control of a patient's body temperature by way of a transluminally insertable heat exchange catheter
US6122551A (en) * 1998-12-11 2000-09-19 Urologix, Inc. Method of controlling thermal therapy
US6019783A (en) * 1999-03-02 2000-02-01 Alsius Corporation Cooling system for therapeutic catheter
US6161049A (en) 1999-03-26 2000-12-12 Urologix, Inc. Thermal therapy catheter
US6272384B1 (en) * 1999-05-27 2001-08-07 Urologix, Inc. Microwave therapy apparatus
US6306132B1 (en) * 1999-06-17 2001-10-23 Vivant Medical Modular biopsy and microwave ablation needle delivery apparatus adapted to in situ assembly and method of use
US6312391B1 (en) * 2000-02-16 2001-11-06 Urologix, Inc. Thermodynamic modeling of tissue treatment procedure
US6477426B1 (en) * 2000-06-20 2002-11-05 Celsion Corporation System and method for heating the prostate gland to treat and prevent the growth and spread of prostate tumors
AU2016204932B2 (en) * 2000-07-21 2019-04-04 Zoll Circulation, Inc. Heat exchanger catheter for controlling body temperature
US6530945B1 (en) * 2000-11-28 2003-03-11 Alsius Corporation System and method for controlling patient temperature
US6641602B2 (en) 2001-04-13 2003-11-04 Alsius Corporation Method and device including a colo-rectal heat exchanger
US6878147B2 (en) * 2001-11-02 2005-04-12 Vivant Medical, Inc. High-strength microwave antenna assemblies
US7128739B2 (en) * 2001-11-02 2006-10-31 Vivant Medical, Inc. High-strength microwave antenna assemblies and methods of use
US6752767B2 (en) 2002-04-16 2004-06-22 Vivant Medical, Inc. Localization element with energized tip
US7258688B1 (en) * 2002-04-16 2007-08-21 Baylis Medical Company Inc. Computerized electrical signal generator
US7197363B2 (en) 2002-04-16 2007-03-27 Vivant Medical, Inc. Microwave antenna having a curved configuration
US7722601B2 (en) 2003-05-01 2010-05-25 Covidien Ag Method and system for programming and controlling an electrosurgical generator system
US7311703B2 (en) 2003-07-18 2007-12-25 Vivant Medical, Inc. Devices and methods for cooling microwave antennas
JP4504718B2 (en) * 2004-03-31 2010-07-14 テルモ株式会社 Heat treatment device
CN1298282C (en) * 2004-09-09 2007-02-07 上海交通大学 Device for controlling and measuring temperature on rectum wall
US20070016272A1 (en) * 2004-09-27 2007-01-18 Thompson Russell B Systems and methods for treating a hollow anatomical structure
US7771418B2 (en) * 2005-03-09 2010-08-10 Sunnybrook Health Sciences Centre Treatment of diseased tissue using controlled ultrasonic heating
US8801701B2 (en) * 2005-03-09 2014-08-12 Sunnybrook Health Sciences Centre Method and apparatus for obtaining quantitative temperature measurements in prostate and other tissue undergoing thermal therapy treatment
US7799019B2 (en) 2005-05-10 2010-09-21 Vivant Medical, Inc. Reinforced high strength microwave antenna
US20070016256A1 (en) * 2005-07-18 2007-01-18 Korb Donald R Method and apparatus for treating gland dysfunction
US20070060988A1 (en) * 2005-07-18 2007-03-15 Grenon Stephen M Melting meibomian gland obstructions
US20090043365A1 (en) 2005-07-18 2009-02-12 Kolis Scientific, Inc. Methods, apparatuses, and systems for reducing intraocular pressure as a means of preventing or treating open-angle glaucoma
US7981145B2 (en) 2005-07-18 2011-07-19 Tearscience Inc. Treatment of meibomian glands
US8950405B2 (en) * 2006-05-15 2015-02-10 Tearscience, Inc. Treatment of obstructive disorders of the eye or eyelid
WO2013003594A2 (en) 2011-06-28 2013-01-03 Tearscience, Inc. Methods and systems for treating meibomian gland dysfunction using radio-frequency energy
US7981095B2 (en) * 2005-07-18 2011-07-19 Tearscience, Inc. Methods for treating meibomian gland dysfunction employing fluid jet
US20080114423A1 (en) 2006-05-15 2008-05-15 Grenon Stephen M Apparatus for inner eyelid treatment of meibomian gland dysfunction
US7981146B2 (en) * 2006-05-15 2011-07-19 Tearscience Inc. Inner eyelid treatment for treating meibomian gland dysfunction
CN102225024B (en) * 2005-07-21 2013-05-01 泰科医疗集团有限合伙公司 Systems and methods for treating a hollow anatomical structure
US8123705B2 (en) * 2005-10-06 2012-02-28 Boston Scientific Scimed, Inc. Adjustable profile probe
US7976573B2 (en) * 2006-05-15 2011-07-12 Tearscience, Inc. Inner eyelid heat and pressure treatment for treating meibomian gland dysfunction
US9314369B2 (en) * 2006-05-15 2016-04-19 Tearscience, Inc. System for inner eyelid treatment of meibomian gland dysfunction
US8128673B2 (en) * 2006-05-15 2012-03-06 Tearscience, Inc. System for inner eyelid heat and pressure treatment for treating meibomian gland dysfunction
US8137390B2 (en) 2006-05-15 2012-03-20 Tearscience, Inc. System for providing heat treatment and heat loss reduction for treating meibomian gland dysfunction
US8007524B2 (en) * 2006-05-15 2011-08-30 Tearscience, Inc. Heat treatment and heat loss reduction for treating meibomian gland dysfunction
US7981147B2 (en) * 2006-05-15 2011-07-19 Tearscience, Inc. Outer eyelid heat and pressure treatment for treating meibomian gland dysfunction
US8128674B2 (en) 2006-05-15 2012-03-06 Tearscience, Inc. System for outer eyelid heat and pressure treatment for treating meibomian gland dysfunction
WO2008027069A1 (en) * 2006-08-21 2008-03-06 Tearscience, Inc. Method and apparatus for treating meibomian gland dysfunction employing fluid
FR2905277B1 (en) * 2006-08-29 2009-04-17 Centre Nat Rech Scient DEVICE FOR THE VOLUMIC TREATMENT OF BIOLOGICAL TISSUES
US8068921B2 (en) 2006-09-29 2011-11-29 Vivant Medical, Inc. Microwave antenna assembly and method of using the same
US7998139B2 (en) 2007-04-25 2011-08-16 Vivant Medical, Inc. Cooled helical antenna for microwave ablation
US8353901B2 (en) 2007-05-22 2013-01-15 Vivant Medical, Inc. Energy delivery conduits for use with electrosurgical devices
US9023024B2 (en) 2007-06-20 2015-05-05 Covidien Lp Reflective power monitoring for microwave applications
US9861424B2 (en) 2007-07-11 2018-01-09 Covidien Lp Measurement and control systems and methods for electrosurgical procedures
US8152800B2 (en) 2007-07-30 2012-04-10 Vivant Medical, Inc. Electrosurgical systems and printed circuit boards for use therewith
US7645142B2 (en) 2007-09-05 2010-01-12 Vivant Medical, Inc. Electrical receptacle assembly
US8747398B2 (en) 2007-09-13 2014-06-10 Covidien Lp Frequency tuning in a microwave electrosurgical system
US8651146B2 (en) 2007-09-28 2014-02-18 Covidien Lp Cable stand-off
WO2009045868A1 (en) * 2007-10-05 2009-04-09 Boston Scientific Scimed, Inc. Thermal monitoring
US8292880B2 (en) 2007-11-27 2012-10-23 Vivant Medical, Inc. Targeted cooling of deployable microwave antenna
US8414501B2 (en) 2007-12-28 2013-04-09 Medifocus, Inc. Thermal monitoring
USD613408S1 (en) 2008-02-06 2010-04-06 Tearscience, Inc. Eye treatment head gear
USD617443S1 (en) 2008-02-06 2010-06-08 Tearscience, Inc. Eye treatment goggles
AU2015203459B2 (en) * 2008-03-31 2016-11-03 Covidien Lp Re-hydration antenna for ablation
US9198723B2 (en) 2008-03-31 2015-12-01 Covidien Lp Re-hydration antenna for ablation
US20100016932A1 (en) * 2008-07-15 2010-01-21 Irving Weinberg Apparatus and method for internal hypothermic radioprotection
US20100087808A1 (en) * 2008-10-03 2010-04-08 Vivant Medical, Inc. Combined Frequency Microwave Ablation System, Devices and Methods of Use
US8372065B2 (en) 2008-11-06 2013-02-12 Nxthera, Inc. Systems and methods for treatment of BPH
DK2352453T3 (en) 2008-11-06 2018-06-14 Nxthera Inc SYSTEMS AND PROCEDURES FOR TREATING PROSTATIC TISSUE
US20110245587A1 (en) * 2010-04-05 2011-10-06 Julie Ann Reil Method for correction of female urinary incontinence and skin reduction
US8961577B2 (en) 2009-04-02 2015-02-24 Julie Ann Reil Correction of female urinary incontinence and skin reduction
US9833277B2 (en) 2009-04-27 2017-12-05 Nxthera, Inc. Systems and methods for prostate treatment
US8954161B2 (en) 2012-06-01 2015-02-10 Advanced Cardiac Therapeutics, Inc. Systems and methods for radiometrically measuring temperature and detecting tissue contact prior to and during tissue ablation
US9226791B2 (en) 2012-03-12 2016-01-05 Advanced Cardiac Therapeutics, Inc. Systems for temperature-controlled ablation using radiometric feedback
US8926605B2 (en) 2012-02-07 2015-01-06 Advanced Cardiac Therapeutics, Inc. Systems and methods for radiometrically measuring temperature during tissue ablation
US9277961B2 (en) 2009-06-12 2016-03-08 Advanced Cardiac Therapeutics, Inc. Systems and methods of radiometrically determining a hot-spot temperature of tissue being treated
US9113925B2 (en) * 2009-09-09 2015-08-25 Covidien Lp System and method for performing an ablation procedure
USD638128S1 (en) 2009-10-06 2011-05-17 Tearscience, Inc. Ocular device design
US11027154B2 (en) 2010-03-09 2021-06-08 Profound Medical Inc. Ultrasonic therapy applicator and method of determining position of ultrasonic transducers
US9707413B2 (en) 2010-03-09 2017-07-18 Profound Medical Inc. Controllable rotating ultrasound therapy applicator
EP2544767B8 (en) 2010-03-09 2019-06-05 Profound Medical Inc. Ultrasonic therapy applicator
WO2011112251A1 (en) 2010-03-09 2011-09-15 Profound Medical Inc. Fluid circuits for temperature control in a thermal therapy system
WO2011115664A2 (en) * 2010-03-14 2011-09-22 Profound Medical Inc. Mri-compatible motor and positioning system
US8632530B2 (en) 2010-03-25 2014-01-21 Nxthera, Inc. Systems and methods for prostate treatment
CN106377312B (en) 2010-10-25 2019-12-10 美敦力Af卢森堡有限责任公司 Microwave catheter apparatus, systems, and methods for renal neuromodulation
US9204922B2 (en) 2010-12-01 2015-12-08 Enable Urology, Llc Method and apparatus for remodeling/profiling a tissue lumen, particularly in the urethral lumen in the prostate gland
PT2755614T (en) 2011-09-13 2018-01-18 Nxthera Inc Systems for prostate treatment
EP2833815B1 (en) 2012-04-03 2020-11-11 Boston Scientific Scimed, Inc. Induction coil vapor generator
US10842670B2 (en) 2012-08-22 2020-11-24 Johnson & Johnson Vision Care, Inc. Apparatuses and methods for diagnosing and/or treating lipid transport deficiency in ocular tear films, and related components and devices
WO2014047355A1 (en) 2012-09-19 2014-03-27 Denervx LLC Cooled microwave denervation
CA2905508A1 (en) 2013-03-14 2014-09-25 Nxthera, Inc. Systems and methods for treating prostate cancer
WO2014179356A1 (en) 2013-04-30 2014-11-06 Tear Film Innovations Llc Systems and methods for the treatment of eye conditions
US9763827B2 (en) 2013-04-30 2017-09-19 Tear Film Innovations, Inc. Systems and methods for the treatment of eye conditions
US10390881B2 (en) 2013-10-25 2019-08-27 Denervx LLC Cooled microwave denervation catheter with insertion feature
US9968395B2 (en) 2013-12-10 2018-05-15 Nxthera, Inc. Systems and methods for treating the prostate
CN108635041B (en) 2013-12-10 2021-04-13 恩克斯特拉公司 Steam ablation system
US20150209107A1 (en) 2014-01-24 2015-07-30 Denervx LLC Cooled microwave denervation catheter configuration
CA2967824A1 (en) 2014-11-19 2016-05-26 Advanced Cardiac Therapeutics, Inc. Ablation devices, systems and methods of using a high-resolution electrode assembly
EP3808298B1 (en) 2014-11-19 2023-07-05 EPiX Therapeutics, Inc. Systems for high-resolution mapping of tissue
EP3220841B1 (en) 2014-11-19 2023-01-25 EPiX Therapeutics, Inc. High-resolution mapping of tissue with pacing
WO2016123498A1 (en) 2015-01-29 2016-08-04 Nxthera, Inc. Vapor ablation systems and methods
US9636164B2 (en) 2015-03-25 2017-05-02 Advanced Cardiac Therapeutics, Inc. Contact sensing systems and methods
EP4275633A3 (en) 2015-05-13 2023-11-22 Nxthera, Inc. Systems and methods for treating the bladder with condensable vapor
US10575901B2 (en) 2015-12-24 2020-03-03 Biosense Webster (Israel) Ltd. Estimating a temperature during ablation
US10213253B2 (en) 2015-12-24 2019-02-26 Biosense Webster (Israel) Ltd. Estimating a temperature during ablation
EP3429462B1 (en) 2016-03-15 2022-08-03 EPiX Therapeutics, Inc. Improved devices and systems for irrigated ablation
US10974063B2 (en) 2016-06-30 2021-04-13 Alcon Inc. Light therapy for eyelash growth
JP7129980B2 (en) 2016-12-21 2022-09-02 ボストン サイエンティフィック サイムド,インコーポレイテッド Steam cautery system and method
EP3565493A4 (en) 2017-01-06 2020-11-11 Nxthera, Inc. Transperineal vapor ablation systems and methods
WO2018200865A1 (en) 2017-04-27 2018-11-01 Epix Therapeutics, Inc. Determining nature of contact between catheter tip and tissue
KR101949940B1 (en) * 2017-12-19 2019-02-19 주식회사 세비카 Low temperature treatment apparatus capable of preventing damage to nerve tissue

Family Cites Families (43)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4190053A (en) * 1977-06-20 1980-02-26 Rca Corporation Apparatus and method for hyperthermia treatment
US4375220A (en) * 1980-05-09 1983-03-01 Matvias Fredrick M Microwave applicator with cooling mechanism for intracavitary treatment of cancer
JPS5957650A (en) * 1982-09-27 1984-04-03 呉羽化学工業株式会社 Probe for heating body cavity
CA1244889A (en) * 1983-01-24 1988-11-15 Kureha Chemical Ind Co Ltd Device for hyperthermia
US4601296A (en) * 1983-10-07 1986-07-22 Yeda Research And Development Co., Ltd. Hyperthermia apparatus
JPS6137259A (en) * 1984-07-31 1986-02-22 菊地 真 Heating apparatus for hyperthermia
IL78756A0 (en) * 1986-05-12 1986-08-31 Biodan Medical Systems Ltd Catheter and probe
US4967765A (en) * 1988-07-28 1990-11-06 Bsd Medical Corporation Urethral inserted applicator for prostate hyperthermia
US5344435A (en) * 1988-07-28 1994-09-06 Bsd Medical Corporation Urethral inserted applicator prostate hyperthermia
FR2639238B1 (en) * 1988-11-21 1991-02-22 Technomed Int Sa APPARATUS FOR SURGICAL TREATMENT OF TISSUES BY HYPERTHERMIA, PREFERABLY THE PROSTATE, COMPRISING MEANS OF THERMAL PROTECTION COMPRISING PREFERABLY RADIOREFLECTIVE SCREEN MEANS
FR2693116B1 (en) * 1992-07-06 1995-04-28 Technomed Int Sa Urethral probe and apparatus for the therapeutic treatment of prostate tissue by thermotherapy.
US5007437A (en) * 1989-06-16 1991-04-16 Mmtc, Inc. Catheters for treating prostate disease
US5097829A (en) * 1990-03-19 1992-03-24 Tony Quisenberry Temperature controlled cooling system
FR2660561B1 (en) * 1990-04-06 1994-05-13 Technomed International RECTAL PROBE.
AU664157B2 (en) * 1990-09-14 1995-11-09 American Medical Systems, Inc. Combined hyperthermia and dilation catheter
JP3091253B2 (en) * 1991-04-25 2000-09-25 オリンパス光学工業株式会社 Thermal treatment equipment
US5304214A (en) * 1992-01-21 1994-04-19 Med Institute, Inc. Transurethral ablation catheter
US5413588A (en) * 1992-03-06 1995-05-09 Urologix, Inc. Device and method for asymmetrical thermal therapy with helical dipole microwave antenna
US5330518A (en) * 1992-03-06 1994-07-19 Urologix, Inc. Method for treating interstitial tissue associated with microwave thermal therapy
DE4207463C2 (en) * 1992-03-10 1996-03-28 Siemens Ag Arrangement for the therapy of tissue with ultrasound
GB9215042D0 (en) * 1992-07-15 1992-08-26 Microwave Engineering Designs Microwave treatment apparatus
US5391197A (en) * 1992-11-13 1995-02-21 Dornier Medical Systems, Inc. Ultrasound thermotherapy probe
EP0597463A3 (en) * 1992-11-13 1996-11-06 Dornier Med Systems Inc Thermotherapiesonde.
US5348554A (en) * 1992-12-01 1994-09-20 Cardiac Pathways Corporation Catheter for RF ablation with cooled electrode
US5405346A (en) * 1993-05-14 1995-04-11 Fidus Medical Technology Corporation Tunable microwave ablation catheter
CA2164860C (en) * 1993-06-10 2005-09-06 Mir A. Imran Transurethral radio frequency ablation apparatus
US5464437A (en) * 1993-07-08 1995-11-07 Urologix, Inc. Benign prostatic hyperplasia treatment catheter with urethral cooling
US5807395A (en) * 1993-08-27 1998-09-15 Medtronic, Inc. Method and apparatus for RF ablation and hyperthermia
EP2314244A1 (en) * 1994-12-13 2011-04-27 Torben Lorentzen An electrosurgical instrument for tissue ablation, an apparatus, and a method for providing a lesion in damaged and diseased tissue from a mammal
US5628770A (en) * 1995-06-06 1997-05-13 Urologix, Inc. Devices for transurethral thermal therapy
US5843144A (en) * 1995-06-26 1998-12-01 Urologix, Inc. Method for treating benign prostatic hyperplasia with thermal therapy
US6302878B1 (en) * 1995-06-27 2001-10-16 S.L.T. Japan Co., Ltd. System for laser light irradiation to living body
US5938692A (en) * 1996-03-26 1999-08-17 Urologix, Inc. Voltage controlled variable tuning antenna
US5676692A (en) * 1996-03-28 1997-10-14 Indianapolis Center For Advanced Research, Inc. Focussed ultrasound tissue treatment method
US5793070A (en) * 1996-04-24 1998-08-11 Massachusetts Institute Of Technology Reduction of trapping effects in charge transfer devices
US5733319A (en) * 1996-04-25 1998-03-31 Urologix, Inc. Liquid coolant supply system
US5987360A (en) * 1996-05-03 1999-11-16 Urologix, Inc. Axial preferential thermal therapy
US5800486A (en) * 1996-06-17 1998-09-01 Urologix, Inc. Device for transurethral thermal therapy with cooling balloon
US5861021A (en) * 1996-06-17 1999-01-19 Urologix Inc Microwave thermal therapy of cardiac tissue
US5792070A (en) * 1996-08-30 1998-08-11 Urologix, Inc. Rectal thermosensing unit
US6051018A (en) * 1997-07-31 2000-04-18 Sandia Corporation Hyperthermia apparatus
US5992419A (en) * 1998-08-20 1999-11-30 Mmtc, Inc. Method employing a tissue-heating balloon catheter to produce a "biological stent" in an orifice or vessel of a patient's body
US6122551A (en) * 1998-12-11 2000-09-19 Urologix, Inc. Method of controlling thermal therapy

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JP2002531218A (en) 2002-09-24
US6490488B1 (en) 2002-12-03
EP1148837A4 (en) 2009-03-11
US6122551A (en) 2000-09-19
EP1148837A1 (en) 2001-10-31
WO2000033767A1 (en) 2000-06-15
AU762862B2 (en) 2003-07-10
EP1148837B1 (en) 2012-09-26
AU3118800A (en) 2000-06-26

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