Urethral inserted applicator for prostate hyperthermia

• US 4,967,765 A
• Filed: 07/28/1988
• Issued: 11/06/1990
• Est. Priority Date: 07/28/1988
• Status: Expired due to Term

• Current Assignee: Ams Research Corporation (Endo International PLC)
• Original Assignee: BSD Medical Corporation
• Inventors: Nguyen, Trung V., Turner, Paul F., Schaefermeyer, Theron N., Tumeh, Amer M.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US07/225,307
• Time in Patent Office: 831 Days
• Field of Search: 128/804, 128/784-786, 128/736, 128/401
• US Class Current: 607/154
• CPC Class Codes: A61B 17/2202 the ultrasound transducer being inside patient's body at the distal end of the catheter
• 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 2017/00057 Light
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/00132 Setting operation time of a device A61B2017/00123 takes precedence
• CPC Class Codes: A61B 2017/00274 Prostate operation, e.g. prostatectomy, turp, bhp treatment
• CPC Class Codes: A61B 2017/22021 electric leads passing through the catheter
• CPC Class Codes: A61B 2018/00035 with return means
• CPC Class Codes: A61B 2018/00166 Multiple lumina
• CPC Class Codes: A61B 2018/00547 Prostate
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61F 7/12 Devices for heating or cooling internal body cavities
• CPC Class Codes: A61M 2025/0177 having external means for receiving guide wires, wires or stiffening members, e.g. loops, clamps or lateral tubes
• CPC Class Codes: A61N 2005/007 for cooling the patient
• CPC Class Codes: A61N 2005/061 Bladder and/or urethra
• CPC Class Codes: A61N 5/0601 Apparatus for use inside the body
• CPC Class Codes: A61N 7/022 intracavitary

Abstract

A urethral inserted applicator for prostate hyperthermia includes a multi-tube, balloon type catheter. The catheter includes first and second closed end fluid dry tubes, respectively, for a helical coil antenna type applicator, and a microwave type temperature sensor for measuring the temperature of the prostate tissue, and an open fluid receiving tube. A microwave generator supplies electromagnetic energy to the applicator. A comparator is connected to the temperature sensor and a temperature reference potentiometer for comparing the actual tissue temperature level with a desired temperature level and outputting control signals to the microwave generator for controlling the output to the applicator. The coil type applicator is an elongated coil having a tip end connected to the center conductor of a coaxial cable and an opposite end connected to the outer conductor of the coaxial cable. A sheet or sheath of insulation material covers the coil antenna for insulating the coil from the tissue and the thickness of the sheet may be varied to provide uniform tissue heating along the length of the coil. The balloon of the catheter engages the body'"'"'s bladder to position the applicator properly during the treatment.

Claims

1. An electromagnetic radiation applicator apparatus for treatment of benign prostatic hyperplasia comprising:

a catheter means for insertion into the urethra;

an applicator means attached to the catheter means, said applicator means including an applicator and a connector means for connecting the applicator to a source of electromagnetic energy sufficient to elevate the temperature of tissue surrounding the applicator to a preselected temperature and for maintaining the preselected temperature during treatment;

positioning means for positioning and maintaining the positioning of the catheter means in the urethra so that the applicator means attached to the catheter means is and remains positioned adjacent the prostate tissue to be treated for as long as desired by the user; and

a temperature sensor supporting means attached to the catheter means for supporting a temperature sensing means in operative association with the applicator of the applicator means for measuring the temperature of the tissue surrounding the applicator.

2. An electromagnetic radiation applicator apparatus according to claim 1, wherein the catheter means has an end thereof adapted to extend from the urethra into the bladder when the catheter means is inserted into the urethra;

wherein the positioning means includes an inflatable balloon mounted exteriorly of the catheter means on a portion thereof which extends into the bladder when the catheter means is positioned in the urethra; and

a passage communicating with the balloon adapted to be connected to a source of pressurized fluid, whereby when the catheter means is positioned within the urethra, the balloon can be inflated within the bladder to engage the bladder opening to the urethra and position the catheter means.

4. An electromagnetic radiation applicator apparatus according to claim 2 wherein the applicator includes a helical coil type antenna.

5. An electromagnetic radiation applicator apparatus according to claim 2 wherein the applicator includes an elongated coil wrapped about the applicator support portion of the catheter means and the applicator means includes a sheath of dielectric material covering the elongated coil sufficiently for producing radiating energy levels along the elongated coil to maintain substantially uniform tissue temperature along the elongated coil.

6. An electromagnetic radiation applicator apparatus according to claim 2 wherein the catheter means includes means for maintaining the position of the applicator means during treatment of the prostate.

7. An electromagnetic radiation applicator apparatus according to claim 6 wherein the means for maintaining the position of the applicator means during treatment includes a fluid drainage tube, an inflatable balloon mounted exteriorly thereof and adjacent to a first end of the fluid drainage tube, and a pressurized fluid source connected to the balloon whereby, when the first end of the fluid drainage tube is positioned within a bladder opening and the balloon inflated, the balloon engages the bladder opening for fixing the location of the applicator means.

8. An electromagnetic radiation applicator apparatus according to claim 2 wherein the temperature sensor supporting tube includes an elongated tube having a closed end portion mounted exteriorly of the fluid free tube, and wherein the temperature sensor means includes a temperature sensor inserted in the elongated tube adjacent the applicator means for measuring the temperature of the tissue adjacent thereto.

9. An electromagnetic radiation applicator apparatus according to claim 2, wherein the catheter means includes a fluid drainage tube.

12. A urethral inserted applicator according to claim 8 wherein the coil has an open connection to the end of the coil toward the insertion tip end of the catheter and center coaxial conductor, an open connection to the end of the coil opposite the insertion tip end of the catheter and the outer coaxial conductor, and conductor gaps within the coil.

3. An electromagnetic radiation applicator apparatus for treatment of benign prostatic hyperplasia comprising:

a catheter means for insertion into the urethra including a fluid free tube, a temperature sensor supporting tube, and an applicator support portion adjacent to a first end of the fluid free tube;

an applicator means including a coaxial cable mounted in the fluid free tube and an applicator mounted on the applicator support portion and connected to the coaxial cable for radiating electromagnetic energy into tissue adjacent to the applicator;

a temperature sensor means including a temperature sensor inserted in the temperature supporting tube for monitoring the temperature of the tissue adjacent to the applicator;

an electromagnetic energy generating means connected to the applicator means for supplying electromagnetic energy thereto;

a control means including a temperature reference means for setting a selected reference temperature to which the tissue is to be heated and a comparator connected to the temperature sensor means and temperature reference means for producing control signals; and

said electromagnetic energy generating means being connected to the control means and responsive to the control signals for supplying electromagnetic energy to the applicator means sufficient to elevating the tissue temperature to the selected reference temperature and maintaining the tissue at the selected temperature during treatment.

10. A urethral inserted applicator for benign prostatic hyperplasia treatment by heating the prostate tissue surrounding the urethra using electromagnetic energy comprising:

a multi-tube urinary catheter, said catheter having an insertion tip end for insertion into the urethra, a fluid dry tube closed at the insertion tip end, and an isolated open ended tube for urine drainage;

a coil type outwardly radiating antenna means including a coil mounted on the catheter and having an end toward the insertion tip end of the catheter, and a coaxial cable positioned in the fluid dry tube and having a center conductor and an outer conductor, the coil being connected to the center conductor of the coaxial cable at its end toward the insertion tip end of the catheter, and to the outer conductor of the coaxial cable at its end opposite the insertion tip end of the catheter; and

dielectric insulation means covering the coil for preventing direct contact of the coil with the tissue.

11. A urethral inserted applicator according to claim 10, wherein the multi-tube urinary catheter further includes at least one additional fluid dry closed end tube, and at least one electromagnetic radiation compatible temperature sensor inserted in said at least one additional fluid dry closed tube for sensing the temperature of prostate tissue.

13. A urethral inserted applicator according to claim 10 wherein the coil has progressively increasing conductor width towards the insertion tip end of the catheter.

14. A urethral inserted applicator according to claim 10 wherein the coil has different turns ratio per unit length.

15. A urethral inserted applicator according to claim 10 wherein the center coaxial cable conductor extends through the center of the coil and wherein the diameter of the center coaxial cable conductor varies as it passes through the coil.

16. A urethral inserted applicator according to claim 10 wherein the thickness of the dielectric insulation means covering the coil varies along the length of the coil.

17. A system for controlling hyperthermia for benign prostatic hyperplasia comprising:

a flexible catheter for insertion into the urethra, said catheter having an applicator means thereon for applying microwave energy to tissues of a prostate gland surrounding the urethra to thereby cause heating of said tissues and a microwave compatible temperature sensor for measuring the temperature of the heated tissues;

a microwave generating means for producing microwaves having a preselected frequency, said microwave generating means being connected to the applicator means to supply microwave to the applicator means; and

a comparator means interconnecting the microwave generating means and microwave compatible temperature sensor for comparing the measured temperature level to a preselected reference temperature level and outputting control signals to the microwave generating means for controlling the supply of microwave power to the applicator means to control the tissue temperature.