DETERMINATION OF ARBITRARY CARDIAC PHASES USING NON-ELECTRICAL SIGNALS

• US 20040111038A1
• Filed: 12/04/2002
• Published: 06/10/2004
• Est. Priority Date: 12/04/2002
• Status: Active Grant

• Current Assignee: GE Medical Systems Global Technology Company LLC (GE Healthcare Technologies, Inc.)
• Original Assignee: GE Medical Systems Global Technology Company LLC (GE Healthcare Technologies, Inc.)
• Inventors: Avinash, Gopal B., Salla, Prathyusha K.
• Granted Patent: US 6,771,999 B2
• Time in Patent Office: Days
• US Class Current: 600/513
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/1107 Measuring contraction of parts of the body, e.g. organ, muscle apparatus for measuring work or force in general G01L
• CPC Class Codes: A61B 5/721 using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured
• CPC Class Codes: A61B 5/7267 involving training the classification device
• CPC Class Codes: A61B 5/7285 for synchronising or triggering a physiological measurement or image acquisition with a physiological event or waveform, e.g. an ECG signal A61B6/5205, A61B6/541, A61B8/5207, A61B8/543 take precedence
• CPC Class Codes: A61B 6/5217 extracting a diagnostic or physiological parameter from medical diagnostic data
• CPC Class Codes: A61B 6/541 involving acquisition triggered by a physiological signal
• CPC Class Codes: A61B 8/543 involving acquisition triggered by a physiological signal
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

A method, storage medium, and system for selecting an optimal trigger point in a cardiac cycle includes providing an input signal including non-electrical cardiac related data, analyzing the input signal to detect candidate features, sorting through the candidate features to select optimal features, and selecting an optimal trigger point. A method, storage medium, and system of selecting an arbitrary cardiac phase for cardiac gating includes identifying a trigger point identifying onset of a systole or diastole phase on a signal, the trigger point existing at time t1, specifying a time δt before the trigger point and extending from a time t0 to a time t1, wherein time t0 is earlier than time t1, and selecting a time interval T over which an image will be reconstructed, wherein the time interval T extends from time t0 to a time t2, wherein time t2 is later than time t0.

Claims

1. A method of selecting an optimal trigger point in a cardiac cycle, the method comprising:

providing an input signal including non-electrical cardiac related data;

analyzing the input signal to detect candidate features;

sorting through the candidate features to select optimal features; and

,

selecting an optimal trigger point.

2. The method of claim 1 further comprising pre-processing the input signal.

3. The method of claim 1 wherein providing the input signal includes both providing raw data and providing pre-processed data.

4. The method of claim 1 further comprising subdividing the input signal into parts.

5. The method of claim 1 further comprising a training process, wherein the training process provides information to at least one step within the method.

6. The method of claim 5 further comprising providing the training process with a training set of data.

7. The method of claim 6 further comprising providing the training set of data with characteristics of normal and abnormal data.

8. The method of claim 1 further comprising categorizing the optimal features prior to selecting an optimal trigger point.

9. The method of claim 1 further comprising applying acquisition parameters to at least one step within the method.

10. The method of claim 1 further comprising using the input signal to compute heart rate.

11. The method of claim 10 further comprising using the heart rate in selecting an optimal trigger point.

12. The method of claim 1 wherein analyzing the input signal to detect candidate features comprises selecting an optimal template from a first few seconds of a dataset for processing.

13. The method of claim 12 further comprising comparing the optimal template to the input signal for finding a correlation vector.

14. The method of claim 13 further comprising thresholding the correlated vector for choosing correlated points in a cardiac cycle, wherein the correlated points identify a set of candidate trigger points.

15. The method of claim 14 further comprising selecting a trigger point with maximum correlation as the optimal trigger point.

16. The method of claim 14 further comprising selecting a trigger point which exceeds a threshold prior to other trigger points as the optimal trigger point.

17. The method of claim 1 further comprising obtaining the input signals from a mechanical sensor.

18. A method of selecting an arbitrary cardiac phase using non-electrical signals for cardiac gating, the method comprising:

identifying a trigger point identifying onset of a systole or diastole phase on a signal, the trigger point existing at time t1;

specifying a time δ

t before the trigger point and extending from a time t0 to a time t1, wherein time t0 is earlier than time t1; and

,

selecting a time interval T over which an image will be reconstructed, wherein

the time interval T extends from time t0 to a time t2, wherein time t2 is later than time t0.

19. The method of claim 18 wherein time t2 is later than time t1.

20. The method of claim 18 wherein the signal is an acceleration signal.

21. The method of claim 18 wherein identifying a trigger point comprises:

providing an input signal including non-electrical cardiac related data;

analyzing the input signal to detect candidate features;

sorting through the candidate features to select optimal features; and

,

selecting an optimal trigger point.

22. The method of claim 21 wherein analyzing the input signal to detect candidate features comprises selecting an optimal template from a first few seconds of a dataset for processing.

23. The method of claim 22 further comprising comparing the optimal template to the input signal for finding a correlation vector.

24. The method of claim 23 further comprising thresholding the correlated vector for choosing correlated points in a cardiac cycle, wherein the correlated points identify a set of candidate trigger points.

25. The method of claim 24 further comprising selecting a trigger point with maximum correlation as the optimal trigger point.

26. The method of claim 24 further comprising selecting a trigger point which exceeds a preselected threshold prior to other trigger points as the optimal trigger point.

27. The method of claim 18 wherein specifying a time δ

t comprises a user selecting a time δ

t.

28. A method of image reconstruction using cardiac gating, the method comprising:

providing a non-electrical signal indicative of a plurality of consecutive cardiac cycles, for each cardiac cycle, the method further comprising;

identifying a trigger point identifying onset of a systole or diastole phase, the trigger point existing at time t1;

specifying a time δ

t before the trigger point and extending from a time t0 to a time t1, wherein time t0 is earlier than time t1;

selecting a time interval T over which an image will be reconstructed, wherein the time interval T extends from time t0 to a time t2, wherein time t2 is later than time t0; and

,

reconstructing an image over at least one time interval T.

29. The method of claim 28 wherein reconstructing an image over at least one time interval T comprises reconstructing an image over two adjacent time intervals T.

30. A storage medium encoded with a machine readable computer program code, said code including instructions for causing a computer to implement a method for selecting an optimal trigger point in a cardiac cycle, the method comprising:

providing an input signal including non-electrical cardiac related data;

analyzing the input signal to detect candidate features;

sorting through the candidate features to select optimal features; and

,

selecting an optimal trigger point.

31. A storage medium encoded with a machine readable computer program code, said code including instructions for causing a computer to implement a method for selecting an arbitrary cardiac phase for cardiac gating, the method comprising:

identifying a trigger point identifying onset of a systole or diastole phase on a signal, the trigger point existing at time t1;

specifying a time δ

t before the trigger point and extending from a time t0 to a time t1, wherein time t0 is earlier than time t1; and

selecting a time interval T over which an image will be reconstructed, wherein

the time interval T extends from time t0 to a time t2, wherein time t2 is later than time t0.

32. A system for selecting an optimal trigger point in a cardiac cycle, the system comprising:

a non-electrical sensor sensing mechanical vibrations of the heart;

a processing circuit coupled to the mechanical sensor, the processing circuit processing a signal sent by the mechanical sensor, analyzing the signal to detect candidate features, sorting through the candidate features to select optimal features, and selecting an optimal trigger point.

33. A system for image reconstruction using cardiac gating, the system comprising:

a non-electrical sensor sensing mechanical vibrations of the heart;

a processing circuit coupled to the mechanical sensor, the processing circuit processing a signal sent by the mechanical sensor, identifying a trigger point identifying onset of a systole or diastole phase on the signal, the trigger point existing at time t1, specifying a time δ

t before the trigger point and extending from a time t0 to a time t1, wherein time to is earlier than time t1, and selecting a time interval T over which an image will be reconstructed, wherein the time interval T extends from time t0 to a time t2, wherein time t2 is later than time t0.