Ultrasound system and method for variable transmission of ultrasonic signals

• US 5,935,069 A
• Filed: 10/10/1997
• Issued: 08/10/1999
• Est. Priority Date: 10/10/1997
• Status: Expired due to Term

• Current Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Original Assignee: Acuson Corporation (Siemens AG)
• Inventors: Block, David J., Chandler, Paul E.
• Primary Examiner(s): Jaworski, Francis J.
• Application Number:
  US08/948,815
• Time in Patent Office: 669 Days
• Field of Search: 600/453-458, 600/437, 600/443, 600/439
• US Class Current: 600/443
• CPC Class Codes: A61B 2017/00703 correcting for movement of heart, e.g. ECG-triggered
• CPC Class Codes: A61B 5/352 Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• CPC Class Codes: A61B 8/481 involving the use of contrast agent, e.g. microbubbles introduced into the bloodstream analysis of echo signal exploiting properties of a contrast enhancer in devices for short-range imaging with acoustic waves G01S7/52039
• CPC Class Codes: A61B 8/543 involving acquisition triggered by a physiological signal

Abstract

An ultrasound system and method for variable transmission of ultrasonic signals are presented. With this method and system, ultrasonic beams can be transmitted into a region in response to a selected event in a reference signal by predicting a future occurrence of a selected event in a reference signal, transmitting a first set of ultrasonic beams into the region at the predicted future occurrence, and transmitting a second set of ultrasonic beams into the region at a selected time interval preceding the predicted future occurrence. Additional applications of the method and system are presented.

Claims

1. A method for transmitting ultrasonic beams in a region using a selected event in a physio reference signal of a patient, said method comprising the steps of:

(a) predicting a future occurrence of a selected event in a physio reference signal of a patient;

(b) determining a future occurrence of a second event by subtracting a selected time interval from the predicted fixture occurrence of the selected event;

(c) transmitting a first set of ultrasonic beams into the region at the second event; and

(d) transmitting a second set of ultrasonic beams into the region at the predicted future occurrence of the selected event.

11. The method of claim 1, 2, 3, 4, 5, or 10, wherein the future occurrence of said selected event is predicted by performing the steps of:

calculating a time difference between the selected event and a first regularly occurring signal in said reference signal; and

adding said time difference to a second regularly occurring signal in said reference signal.

12. The method of claim 1, 2, 3, 4, or 5 further comprising the steps of:

(d) calculating a difference between a first and a second occurrence of a regularly occurring signal in said reference signal; and

(e) re-transmitting both sets of ultrasound beams in response to said difference exceeding a selected threshold.

13. The method of claim 12, wherein said regularly occurring signal is an R-wave and wherein said reference signal is an ECG signal.

14. The method of claim 12 further comprising the step of:

(f) calculating a time difference between an occurrence of a selected event and a predicted future occurrence of said selected event, each with respect to a regularly occurring signal in the reference signal; and

(g) re-transmitting both sets of ultrasound beams in response to said time difference in step (f) exceeding a selected threshold.

15. The method of claim 1, 2, 3, 4, 5, or 10, wherein said reference signal is a respiration signal.

16. The method of claim 1, 2, 3, 4, 5, or 10, wherein said reference signal is an ECG signal.

2. A method for performing an ultrasound examination on a region comprising blood and contrast agent, said method comprising the steps of:

(a) predicting a future occurrence of a selected event in a physio reference signal of a patient;

(b) determining a future occurrence of a second event by subtracting a selected time interval from the predicted future occurrence of the selected event;

(c) transmitting a set of higher power ultrasonic signals into the region, said set of higher power ultrasonic signals operative to selectively disrupt the contrast agent in the region to create a reduced concentration of operative contrast agent; and

(d) transmitting a set of lower power ultrasonic signals into the region to image the contrast agent in the region, said set of lower power ultrasonic signals disrupting the contrast agent to a lesser extent than the set of higher power ultrasonic signals;

one of steps c or d being synchronized with the predicted future occurrence of the selected event and the other of steps c or d being performed at the second event.

3. A method for performing an ultrasound examination on a region comprising blood and contrast agent in a body, said method comprising the steps of:

(a) predicting a future occurrence of a selected event in a physio reference signal of a patient;

(b) determining a future occurrence of a second event by subtracting a selected time interval from the predicted future occurrence of the selected event;

(c) transmitting a set of higher power ultrasonic signals into the region, said set of higher power ultrasonic signals operative to selectively activate the contrast agent in the region to create an enhanced concentration of operative contrast agent; and

(d) transmitting a set of lower power ultrasonic signals into the region to image the contrast agent in the region, said set of lower power ultrasonic signals activating the contrast agent to a lesser extent than the set of higher power ultrasonic signals;

one of steps c or d being synchronized with the predicted future occurrence of the selected event and the other of steps c or d being performed at the second event.

4. A method for performing an ultrasound examination on a region comprising blood and contrast agent, said method comprising the steps of:

(a) predicting a future occurrence of a selected event in a physio reference signal of a patient;

(b) determining a future occurrence of a second event by subtracting a first time interval from the predicted future occurrence of the selected event;

(c) transmitting a set of higher power ultrasonic signals into the region, said set of higher power ultrasonic signals operative to selectively disrupt the contrast agent in the region to create a reduced concentration of operative contrast agent; and

(d) transmitting a set of lower power ultrasonic signals into the region to measure a concentration level of contrast agent in the region, said set of lower power ultrasonic signals disrupting the contrast agent to a lesser extent than the set of higher power ultrasonic signals, one of steps c or d being synchronized with the predicted future occurrence of the selected event and the other of steps c or d being performed at the second event; and

(e) repeating steps (a) through (d) at a second time interval.

6. The method of claim 4 or 5, wherein the measured concentration level is used to calculate perfusion of said region.

7. The method of claim 4 or 5, wherein the second time interval is greater than the first time interval.

8. The method of claim 4 or 5, wherein the second time interval is less than the first time interval.

9. The method of claim 4 or 5, wherein the second time interval is greater than a period of a regularly occurring signal in the reference signal.

5. A method for performing an ultrasound examination on a region comprising blood and contrast agent in a body, said method comprising the steps of:

(a) predicting a future occurrence of a selected event in a physio reference signal of a patient;

(b) determining a future occurrence of a second event by subtracting a first time interval from the predicted future occurrence of the selected event;

(c) transmitting a set of higher power ultrasonic signals into the region, said set of higher power ultrasonic signals operative to selectively activate the contrast agent in the region to create an enhanced concentration of operative contrast agent; and

(d) transmitting a set of lower power ultrasonic signals into the region to measure a concentration level of contrast agent in the region, said set of lower power ultrasonic signals activating the contrast agent to a lesser extent than the set of higher power ultrasonic signals, one of steps c or d being synchronized with the predicted future occurrence of the selected event and the other of steps c or d being performed at the second event; and

(e) repeating steps (a) through (d) at a second time interval.

10. A method for physio-signal activation of a surgical tool before an anticipated transmission of a set of ultrasonic beams, said method comprising the steps of:

(a) predicting a future occurrence of a selected event in a physio reference signal of a patient;

(b) determining a future occurrence of a second event by subtracting a selected time interval from the predicted future occurrence of the selected event;

(c) transmitting a first set of ultrasonic beams into the region at the second event; and

(d) activating a surgical tool to perform an action in the region at the predicted future occurrence of the selected event.

17. In an ultrasound imaging system comprising a transmit beamformer, a receive beamformer, a transducer responsive to the transmit beamformer and coupled to the receive beamformer, and means for providing a physio reference signal, the improvement comprising:

means, responsive to the reference signal, for predicting a future occurrence of a selected event in the reference signal;

means, responsive to the reference signal, for determining a future occurrence of a second event by subtracting a first time interval from the predicted future occurrence of the selected event;

means, coupled to the transmit beamformer for transmitting a first set of ultrasonic beams into the region at the second event, and means, coupled to the transmit beamformer, for transmitting a second set of ultrasonic beams into the region at the predicted future occurrence.

18. The invention of claim 17 further comprising means, coupled to the transmit beamformer, for synchronizing one ultrasonic beam transmission with a predicted future occurrence of a selected event in a reference signal and performing another ultrasonic beam transmission at a selected time interval preceding the predicted future occurrence.