Claims
- 1. An NMR system for producing an image of a subject undergoing motion, the combination comprising:
- means for acquiring a plurality of sets of NMR image data;
- means for acquiring with each set of image data an associated set of motion data that indicates motion of the subject during each view of acquired image data;
- means for generating a smooth reference curve for each set of acquired motion data;
- means for determining the deviation of the acquired motion data from a reference curve; and
- means for combining each view in the sets of NMR image data by weighting the NMR image data as a function of the deviation of its associated motion data.
- 2. The NMR system as recited in claim 1 in which the means for acquiring the sets of motion data includes means for producing a motion NMR pulse sequence and the means for acquiring the sets of NMR image data includes means for producing an image NMR pulse sequence; and each of said data sets is acquired in a scan comprised of a plurality of image NMR pulse sequences interleaved with a plurality of the motion NMR pulse sequences.
- 3. The NMR system as recited in claim 2 in which the motion data in each set indicates the displacement of a feature in the subject from a reference position, and the smooth reference curve is generated by fitting a curve to the displacement values in the motion data set.
- 4. The NMR system as recited in claim 3 in which the means for combining each view weights the NMR image data in each set inversely proportional to the magnitude of the deviation of its associated motion data from the reference curve.
- 5. The system as recited in claim 1 in which two sets of NMR image data S.sub.1 (k.sub.y) and S.sub.2 (k.sub.y) are acquired along with two sets of associated motion NMR data, the means for determining deviation produces two sets of deviation data D.sub.1 (k.sub.y) and D.sub.2 (k.sub.y), and the means for combining each view in the sets of NMR image data performs the following calculations:
- S(k.sub.y)=S.sub.1 (k.sub.y) (W.sub.1 (k.sub.y))+S.sub.2 (k.sub.y) (W.sub.2 (k.sub.y));
- where:
- W.sub.1 (k.sub.y)=D.sub.2 (k.sub.y)/(D.sub.1 (k.sub.y)+D.sub.2 (k.sub.y)); and
- W.sub.2 (k.sub.y)=D.sub.1 (k.sub.y)/(D.sub.1 (k.sub.y)+D.sub.2 (k.sub.y)).
RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 401,374 filed on Aug. 31, 1989 now abandoned and a continuation-in-part of U.S. patent application Ser. No. 427,401 filed on Oct. 27, 1989.
US Referenced Citations (3)
Related Publications (1)
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Date |
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401374 |
Aug 1989 |
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Continuation in Parts (1)
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Number |
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427401 |
Oct 1989 |
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