FORMATION OF ULTRASOUND BASED HEATING REGIONS ADJACENT BLOOD VESSELS

• US 20110066085A1
• Filed: 11/22/2010
• Published: 03/17/2011
• Est. Priority Date: 11/26/1999
• Status: Abandoned Application

• Current Assignee: Otsuka Medical Devices Co., Ltd. (Otsuka Holdings Company Limited)
• Original Assignee: Kona Medical, Inc.
• Inventors: Zhang, Jimin, Perozek, David M., Weng, Lee
• Application Number:
  US12/951,850
• Publication Number:
  US 20110066085A1
• Time in Patent Office: Days
• US Class Current: 601/3
• CPC Class Codes: A61B 2017/4216 Operations on uterus, e.g. endometrium
• CPC Class Codes: A61B 2090/378 using ultrasound
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/4281 characterised by sound-transmitting media or devices for coupling the transducer to the tissue
• CPC Class Codes: A61B 8/445 Details of catheter construction
• CPC Class Codes: A61B 8/546 involving monitoring or regulation of device temperature
• CPC Class Codes: A61N 2007/0052 using the same transducer for therapy and imaging
• CPC Class Codes: A61N 7/00 Ultrasound therapy lithotripsy A61B17/22, A61B17/225; massage using supersonic vibration A61H23/00 ; using ultrasound for introducing media into the body A61M37/0092
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00
• CPC Class Codes: A61N 7/022 intracavitary

Abstract

An ultrasound system used for both imaging and delivery high intensity ultrasound energy therapy to treatment sites and a method for treating tumors and other undesired tissue within a patient'"'"'s body with an ultrasound device. The ultrasound device has an ultrasound transducer array disposed on a distal end of an elongate, relatively thin shaft. In one form of the invention, the transducer array is disposed within a liquid-filled elastomeric material that more effectively couples ultrasound energy into the tumor, that is directly contacted with the device. Using the device in a continuous wave mode, a necrotic zone of tissue having a desired size and shape (e.g., a necrotic volume selected to interrupt a blood supply to a tumor) can be created by controlling at least one of the f-number, duration, intensity, and direction of the ultrasound energy administered. This method speeds the therapy and avoids continuously pausing to enable intervening normal tissue to cool.

Claims

1. A method comprising:

providing an ultrasonic transducer array configured to emit focused high intensity ultrasound energy;

determining a treatment zone; and

energizing the ultrasonic transducer array to cause pre-focal heating of a substantial portion of tissue between the transducer array and a focal point of the transducer array, wherein the focal point is directed to the treatment zone.

2. The method of claim 1, wherein the pre-focal heating raises a temperature of the tissue to about 50°

C.

3. The method of claim 2, wherein energizing the ultrasonic transducer array raises a temperature of the focal point to between about 70°

C. and about 90°

C.

4. The method of claim 3, wherein energizing the ultrasonic transducer array forms a lesion at the focal point.

5. The method of claim 1, wherein the treatment zone is determined such that a necrosis at the treatment zone causes a decrease in a blood supply to a tumor.

6. The method of claim 1, comprising imaging the treatment zone.

7. The method of claim 6, wherein the ultrasonic transducer array is configured to emit ultrasound imaging pulses.

8. The method of claim 6, wherein energizing the ultrasonic transducer array to cause pre-focal heating and imaging the treatment zone are performed simultaneously.

9. The method of claim 6, wherein imaging the treatment zone comprises Doppler flow imaging of blood flow.

10. The method of claim 1, further comprising disposing a balloon between the ultrasonic transducer array and the treatment zone to acoustically couple the ultrasonic transducer array with the treatment zone.

11. The method of claim 10, wherein the balloon comprises a semi-permeable membrane.

12. The method of claim 1, wherein the treatment zone includes a volume disposed adjacent to a blood vessel.

13. The method of claim 1, further comprising introducing the ultrasonic transducer array into a body cavity.

14. The method of claim 1, wherein the ultrasonic transducer array is further configured to generate ultrasonic pulses and to receive ultrasonic echoes.

15. A method comprising:

providing an ultrasonic transducer array configured to emit focused high intensity ultrasound energy;

determining a treatment zone disposed adjacent to a blood vessel; and

energizing the ultrasonic transducer array to cause pre-focal heating of a substantial portion of tissue between the transducer array and a focal point of the transducer array, wherein the focal point is directed to the treatment zone.

16. The method of claim 15, further comprising providing an ultrasonic signal to the ultrasonic transducer array.