DEVICES AND METHODS FOR USING CONTROLLED BUBBLE CLOUD CAVITATION IN FRACTIONATING URINARY STONES

• US 20110054363A1
• Filed: 08/26/2010
• Published: 03/03/2011
• Est. Priority Date: 08/26/2009
• Status: Active Grant

• Current Assignee: HistoSonics, Inc, Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: HistoSonics, Inc
• Inventors: Hall, Timothy L., Roberts, William W., Fowlkes, J. Brian, Cain, Charles A., Xu, Zhen, Davison, Thomas W.
• Granted Patent: US 9,901,753 B2
• Time in Patent Office: Days
• US Class Current: 601/4
• CPC Class Codes: A61B 17/225 for extracorporeal shock wave lithotripsy [ESWL], e.g. by using ultrasonic waves
• CPC Class Codes: A61B 17/2256 with means for locating or checking the concrement, e.g. X-ray apparatus, imaging means A61B17/2255 takes precedence
• CPC Class Codes: A61B 2017/00172 Pulse trains, bursts, intermittent continuous operation
• CPC Class Codes: A61B 2017/22008 used or promoted
• CPC Class Codes: A61B 2090/378 using ultrasound
• CPC Class Codes: A61B 8/00 Diagnosis using ultrasonic, sonic or infrasonic waves imaging of objects using sonar G01S15/00
• 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

Abstract

A medical imaging and therapy device is provided that may include any of a number of features. One feature of the device is that it can deliver Lithotripsy therapy to a patient, so as to fractionate urinary stones. Another feature of the device is that it can deliver Histotripsy therapy to a patient, so as to erode urinary stones. In some embodiments, the medical imaging and therapy device is configured to target and track urinary stones in the patient during therapy. Methods associated with use of the medical imaging and therapy device are also covered.

Claims

1. A Lithotripsy-Histotripsy system, comprising:

a first therapy transducer configured to deliver Lithotripsy therapy to a target;

a second therapy transducer configured to deliver Histotripsy therapy to the target; and

a control system configured to switch between delivering Lithotripsy therapy from the first therapy transducer to delivering Histotripsy therapy from the second therapy transducer.

2. The Lithotripsy-Histotripsy system of claim 1 wherein the first therapy transducer is configured to apply acoustic pulses that operate at a frequency between approximately 50 KHz and 5 MHz, having a pulse intensity with a peak negative pressure of approximately 10-25 MPa, a peak positive pressure of more than 10 MPa, a pulse length of 1 cycle, a duty cycle less than 0.1%, and a pulse repetition frequency of less than 2 Hz.

3. The Lithotripsy-Histotripsy system of claim 1 wherein the second therapy transducer is configured to apply acoustic pulses that operate at a frequency between approximately 50 KHz and 5 MHz, having a pulse intensity with a peak negative pressure of approximately 8-40 MPa, a peak positive pressure of more than 10 MPa, a pulse length shorter than 50 cycles, a duty cycle of less than 5%, and a pulse repetition frequency of less than 5 KHz.

4. The Lithotripsy-Histotripsy system of claim 1 further comprising an imaging system.

5. The Lithotripsy-Histotripsy system of claim 4 wherein the imaging system comprises a fluoroscopic imaging system.

6. The Lithotripsy-Histotripsy system of claim 4 wherein the imaging system comprises an ultrasound imaging system.

7. The Lithotripsy-Histotripsy system of claim 4 wherein the imaging system comprises a combination fluoroscopic and ultrasound imaging system.

8. The Lithotripsy-Histotripsy system of claim 4 wherein the imaging system is configured to target and track a urinary stone in a patient.

9. A Lithotripsy-Histotripsy system, comprising:

a multi-mode therapy transducer configured to deliver Lithotripsy therapy and Histotripsy therapy to a target; and

a control system configured to switch between delivering Lithotripsy therapy from the multi-mode therapy transducer to delivering Histotripsy therapy from the multi-mode therapy transducer.

10. The Lithotripsy-Histotripsy system of claim 9 wherein the multi-mode therapy transducer is configured to apply acoustic pulses that operate at a frequency between approximately 50 KHz and 5 MHz, having a pulse intensity with a peak negative pressure of approximately 10-25 MPa, a peak positive pressure of more than 10 MPa, a pulse length of 1 cycle, a duty cycle less than 0.1%, and a pulse repetition frequency of less than 2 Hz, so as to deliver Lithotripsy therapy to the target.

11. The Lithotripsy-Histotripsy system of claim 9 wherein the multi-mode therapy transducer is configured to apply acoustic pulses that operate at a frequency between approximately 50 KHz and 5 MHz, having a pulse intensity with a peak negative pressure of approximately 8-40 MPa, a peak positive pressure of more than 10 MPa, a pulse length shorter than 50 cycles, a duty cycle of less than 5%, and a pulse repetition frequency of less than 5 KHz, so as to deliver Histotripsy therapy to the target.

12. The Lithotripsy-Histotripsy system of claim 9 further comprising an imaging system.

13. The Lithotripsy-Histotripsy system of claim 12 wherein the imaging system comprises a fluoroscopic imaging system.

14. The Lithotripsy-Histotripsy system of claim 12 wherein the imaging system comprises an ultrasound imaging system.

15. The Lithotripsy-Histotripsy system of claim 12 wherein the imaging system comprises a combination fluoroscopic and ultrasound imaging system.

16. The Lithotripsy-Histotripsy system of claim 12 wherein the imaging system is configured to target and track a urinary stone in a patient.

17. A method of treating urinary stones, comprising:

applying Histotripsy therapy to generate a bubble cloud;

positioning the bubble cloud on a urinary stone;

applying Lithotripsy therapy to generate a shock wave to fractionate the urinary stone into macroscopic urinary stone particles; and

applying Histotripsy therapy to the macroscopic urinary stone particles to erode the macroscopic urinary stone particles.

18. The method of claim 17 wherein the positioning step further comprises positioning the bubble cloud on the urinary stone under imaging guidance.

19. The method of claim 17 wherein the positioning step further comprises positioning the bubble cloud on the urinary stone under ultrasound imaging guidance.

20. The method of claim 17 wherein the positioning step further comprises positioning the bubble cloud on the urinary stone under fluoroscopic and ultrasound imaging guidance.

21. The method of claim 17 wherein the applying Histotripsy therapy steps comprise applying Histotripsy therapy with a multi-mode transducer.

22. The method of claim 21 wherein the applying Lithotripsy therapy step comprises applying Lithotripsy therapy with the multi-mode transducer.

23. The method of claim 17 wherein the applying Histotripsy therapy steps comprise applying Histotripsy therapy at a first pulse repetition frequency, wherein the applying Lithotripsy therapy step comprises applying Lithotripsy therapy at a second pulse repetition frequency, the method further comprising interleaving Histotripsy therapy and Lithotripsy therapy with virtually no change in the first and second pulse repetition rates.

24. A method of treating a target tissue, comprising:

delivering a first Lithotripsy pulse to the target tissue;

delivering a sequence of Histotripsy pulses to the target tissue after the first Lithotripsy pulse; and

delivering a second Lithotripsy pulse to the target tissue after the sequence of Histotripsy pulses, wherein the first and second Lithotripsy pulses are separated in time by a pulse repetition frequency.

25. The method of claim 24 wherein the target tissue is a urinary stone.

26. The method of claim 24 further comprising delivering a sequence of Histotripsy pulses immediately prior to delivering the first Lithotripsy pulse to the target tissue to suppress cavitation.

27. The method of claim 26 further comprising delivering a sequence of Histotripsy pulses immediately prior to delivering the second Lithotripsy pulse to the target tissue to suppress cavitation.

28. The method of claim 24 further comprising delivering a spatially-varying cavitation suppressing Histotripsy field to allow cavitation to occur within the target tissue while suppressing cavitation outside the target tissue.