System and method for sensing and locating disturbances in an energy path of a focused ultrasound system

• US 7,175,596 B2
• Filed: 10/29/2001
• Issued: 02/13/2007
• Est. Priority Date: 10/29/2001
• Status: Expired due to Term

• Current Assignee: InSightec Ltd.
• Original Assignee: Insightec-Txsonics Limited
• Inventors: Vitek, Shuki, Ezion, Avner
• Primary Examiner(s): Casler; Brian L.
• Assistant Examiner(s): JUNG, WILLIAM C
• Application Number:
  US10/020,737
• Publication Number:
  US 20030083597A1
• Time in Patent Office: 1,933 Days
• Field of Search: 600/407, 600/411, 600/425, 600/427, 600437-439, 601 1- 5
• US Class Current: 600/439
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00
• CPC Class Codes: G01S 15/8909 using a static transducer configuration
• CPC Class Codes: G01S 7/52025 for pulse systems G01S7/52034 takes precedence
• CPC Class Codes: G01S 7/52058 displaying one measured variable; A-scan display

Abstract

A method for sensing a disturbance in a transmission path of a converging ultrasound energy beam transmitted by a transducer in a focussed ultrasound system comprises transmitting a burst of ultrasound energy from the transducer, detecting whether a reflected portion of the ultrasound energy burst is received at the transducer within a certain time period following transmission of the burst, and, if so, analyzing the received reflected portion to determine a characteristic of the disturbance.

Claims

1. A method for sensing a disturbance in a transmission path of a converging ultrasound energy beam transmitted by a transducer in a focused ultrasound system, the method comprising:

transmitting a burst of ultrasound energy from the transducer, along the transmission path, to a focal zone;

detecting whether a reflected portion of the ultrasound energy burst is received at the transducer within a certain time period following transmission of the burst, wherein receipt within the time period indicates the reflected portion was reflected by a disturbance located in the transmission path proximal of the focal zone; and

determining the location of the disturbance based, at least in part, on a delay time from the transmission of the ultrasound energy burst to the reception of the reflected portions of the ultrasound energy bursts from the proximally located disturbance.

2. The method of claim 1, further comprising analyzing the received reflected portion from the disturbance and determining an intensity of the reflected portion.

3. The method of claim 2, further comprising determining at least one or more characteristics of the disturbance based, at least in part, on the determined intensity of the reflected portion.

4. The method of claim 3, further comprising detecting whether a reflected portion of the ultrasound energy burst is received at the transducer comprises sampling each transducer element after simultaneously transmitting a burst of ultrasound energy from each of the transducer elements to determine which, if any, transducer element receives a reflected portion of the burst.

5. The method of claim 4, further comprising repeating each step one or more times.

6. The method of claim 4, further comprising analyzing the received reflected portion from the disturbance and determining a delay time from when the burst was transmitted to when the reflected portion was received at the transducer for each transducer element that receives a reflected portion of the ultrasound energy burst.

7. The method of claim 1, wherein the transducer comprises an array of transducer elements, and wherein transmitting a burst of ultrasound energy from the transducer comprises simultaneously transmitting a burst of ultrasound energy from each of the transducer elements.

8. The method of claim 1, further comprising storing data related to a received reflected portion of the ultrasound energy burst.

9. The method of claim 8, wherein the stored data related to a received reflected portion of the ultrasound energy burst comprises at least one of a group consisting of a determined delay time from when the burst was transmitted to when the received reflected portion was received at the transducer, a determined distance from the transducer to a disturbance reflecting the respective portion back to the transducer, and a determined intensity of the reflected portion.

10. The method of claim 1, further comprising displaying information related to a received reflected portion of the ultrasound energy burst.

11. The method of claim 10, wherein displaying information comprises overlaying data related to a received reflected portion on an image of the transducer in order to indicate a portion of the transducer which received the reflection.

12. The method of claim 11, further comprising displaying the information as a single trace of data.

13. The method of claim 1, further comprising switching a transducer used to transmit the burst of ultrasound energy from continuous wave operation to burst operation before transmitting the burst of ultrasound energy, and thereafter switching the transducer from burst operation to continuous wave operation after a time period required for the burst of ultrasound energy to travel from the transducer to the focal zone and back to the transducer.

14. A focused ultrasound system comprising:

a transducer configured to transmit a burst of ultrasound energy in a converging transmission path to a focal zone, and to received reflected portions of the ultrasound energy burst,

the system configured to analyze reflected portions of an ultrasound energy burst received by the transducer within a certain time period following transmission of the respective burst and to determine the location of a disturbance located in the transmission path proximal of the focal zone based, at least in part on a delay time from the transmission of the ultrasound energy burst to the reception of the reflected portions of the ultrasound enemy burst from the disturbance.

15. The focused ultrasound system of claim 14, wherein analysis of the received reflected portion comprises determining a distance from the transducer to the disturbance based, at least in part, on the determined delay time.

16. The focused system of claim 14, wherein analysis of the received reflected portion comprises determining an intensity of the reflected portion from the disturbance.

17. The focused ultrasound system of claim 16, wherein analysis of the received reflected portion comprises determining a characteristic of the disturbance based, at least in part, on the determined intensity of the reflected portion.

18. The focused ultrasound system of claim 14, wherein the transducer comprises an array of transducer elements, and wherein the system is further configured to simultaneously transmit a burst of ultrasound energy from each transducer array element.

19. The focused ultrasound system of claim 18, further configured to sample each of the transducer array elements to determine which if any received a reflection of the ultrasound energy from the disturbance in the path of the ultrasound energy.

20. The focused ultrasound system of claim 19, further configured to transmit a series of ultrasound energy bursts from each transducer array element.

21. The focused ultrasound system of claim 20, further configured to serially sample each of the transducer army elements after each transmission in the series of transmitted ultrasound energy bursts.

22. The focused ultrasound system of claim 19, further configured to determine a delay from transmission of a burst of ultrasound energy to reception of a reflection for each transducer element that receives a reflection.

23. The focused ultrasound system of claim 14, further comprising a memory, wherein the system is configured to store information related to the received reflection in the memory.

24. The focused ultrasound system of claim 14, further comprising a display, and wherein the system is configured to display information related to the received reflection on the display.

25. The focused ultrasound system of claim 24, further configured to display the information related to the received reflection overlaid on an image of the transducer.

26. The focused ultrasound system of claim 24, further configured to display the information related to the received reflection as a single trace.

27. The focused ultrasound system of claim 24, further configured to generate a 3D reconstruction of the disturbance, and to display the 3D reconstruction on the display.

28. The focused ultrasound system of claim 14, further comprising a controller communicatively coupled with the transducer, the controller configured to control the operation of the transducer.

29. The focused ultrasound system or claim 28, wherein the controller is configured to switch the transducer from continuous wave operation to burst operation before the transmitter transmits the burst of ultrasound energy and to switch the transducer back to continuous wave operation after a time period required for the ultrasound energy to travel from the transducer to a focal spot of the transducer and back to the transducer again.

30. The focused ultrasound system of claim 14, further comprising a processor, wherein the processor determines the range from the transducer to the disturbance that generated the reflection.

31. The focused ultrasound system of claim 30, wherein the processor determines the phase and amplitude of the received reflection.

32. The focused ultrasound system of claim 31, wherein the transducer comprises an array of transducer elements, and wherein the processor determines the phase and amplitude of the received reflection relative to each transducer array element.

33. The focused ultrasound system of claim 30, further configured to analyze the integrity of the burst of ultrasound energy transmission path.