ANALYSIS OF REAL TIME BACKSCATTER DATA FOR FAULT SIGNAL GENERATION IN A MEDICAL HIFU DEVICE

• US 20100241034A1
• Filed: 03/23/2010
• Published: 09/23/2010
• Est. Priority Date: 03/23/2009
• Status: Active Grant

• Current Assignee: Solta Medical, Inc. (Bausch Health Cos., Inc.)
• Original Assignee: Medicis Technologies Corporation
• Inventors: Little, Blake
• Granted Patent: US 9,816,968 B2
• Time in Patent Office: Days
• US Class Current: 601/2
• CPC Class Codes: A61B 2017/00119 alarm; indicating an abnormal situation
• CPC Class Codes: A61B 2017/00123 and automatic shutdown
• CPC Class Codes: A61B 2017/00725 Calibration or performance testing
• CPC Class Codes: A61N 2007/0078 with multiple treatment transducers
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00
• CPC Class Codes: G01N 2291/044 Internal reflections (echoes), e.g. on walls or defects
• CPC Class Codes: G01N 29/30 Arrangements for calibrating or comparing, e.g. with standard objects
• CPC Class Codes: G01N 29/343 pulse waves, e.g. particular sequence of pulses, bursts
• CPC Class Codes: G01N 29/4427 with stored values, e.g. threshold values
• CPC Class Codes: G01N 29/4454 Signal recognition, e.g. specific values or portions, signal events, signatures

Abstract

A method and system for checking functionality of an ultrasound therapy head. The waveform profile for typical ultrasound reflections for a functional therapy head are stored, and before use of a therapy head, an ultrasound energy burst (700) is sent, and the actual waveform profile of the returned reflections (702) are compared to the stored waveform profiles (706). If the actual profiles are not sufficiently close to the stored profiles, then a first signal (712) may be generated, which may cause the ultrasound therapy device to shut down or may generate a warning. If the actual profiles are sufficiently close to the stored profiles, then operation may continue (714), or a second signal may be produced, permitting operation of the ultrasound therapy device.

Claims

1. A medical ultrasound therapy system, comprising:

a therapy head;

a high intensity ultrasound transducer mounted in the therapy head;

a data store storing information about expected waveform profiles of reflections of the transducer; and

a controller linked to the data store and the transducer and operative to compare actual waveform profiles to the stored expected waveform profiles and to generate a first signal if the profiles do not substantially match.

2. The system of claim 1, wherein the controller is further operative to generate a second signal if the profiles do substantially match

3. The system of claim 1, wherein the second signal enables a treatment operation by the transducer.

4. The system of claim 1, wherein the first signal disables a treatment operation by the transducer.

5. In a high intensity focused ultrasound therapy system, a method for detecting a system fault, the method comprising:

transmitting a burst of ultrasonic energy from a high intensity focused ultrasound transducer mounted in a therapy head;

capturing a ring down waveform after the burst;

comparing the ring down waveform to an expected ring down waveform profile; and

generating a fault signal if the ring down waveform does not substantially match the expected ring down waveform profile.

6. The method of claim 5, wherein one or more expected ring down waveform profile(s) are stored on a persistent memory device.

7. The method of claim 5, further comprising:

preventing a high intensity focused ultrasound therapy system from operating after the fault signal is generated.

8. In a high intensity focused ultrasound therapy system, a method for detecting a transducer fault, the method comprising:

transmitting a burst of ultrasonic energy from a high intensity focused ultrasound transducer mounted in a therapy head;

applying a clamp impedance across the transducer;

comparing the residual electrical voltage (clamp waveform) against a stored clamp waveform profile; and

generating a fault signal if the clamp waveform does not substantially match the stored clamp waveform profile.

9. The method of claim 8, wherein one or more expected clamp waveform profile(s) are stored on a persistent memory device.

10. The method of claim 8, further comprising:

preventing a high intensity focused ultrasound therapy system from operating after the fault signal is generated.

11. A method of determining functionality of an ultrasound therapy head, the method comprising:

transmitting a burst of ultrasonic energy via a transducer that is mounted in a liquid filled therapy head;

receiving one or more reflections from objects within the therapy head, the reflections comprising at least one waveform profile;

comparing said at least one waveform profile to an expected waveform profile for the therapy head; and

generating a fault signal if the waveform profile of the reflection does not meet the expected waveform profile.

12. The method of claim 11, wherein the expected waveform profile comprises an expected amplitude range at a particular range of delays from the burst.

13. The method of claim 11, wherein the expected waveform profile comprises an expected maximum amplitude during an expected range of time after the burst.

14. The method of claim 11, wherein the expected waveform profile comprises an expected minimum amplitude during an expected range of time after the burst.

15. The method of claim 11, wherein the expected waveform profile comprises a permitted deviation from a plurality of defined amplitudes, each defined amplitude being a different delay from the burst.

16. The method of claim 11, further comprising generating a second signal if the actual waveform profile of the reflection does meet the expected waveform profile.

17. The method of claim 11, wherein a plurality of reflections are arranged in sequence and compared to a corresponding sequence of expected waveform profiles, the arrangement of reflections and expected waveforms being a linear time sequence.

18. The method of claim 17, wherein the expected waveform profile comprises a permitted deviation from a plurality of defined amplitudes, each defined amplitude being a different delay from the burst.

19. The method of claim 17, wherein the expected waveform profile comprises a plurality of expected amplitude ranges, each expected amplitude range at a different delay from the burst.

20. The method of claim 17, wherein the expected waveform profile comprises a plurality of expected maximum amplitudes, each expected maximum amplitude at a different expected range of time after the burst.