Surgery – Truss – Pad
Patent
1983-08-15
1986-07-29
Coven, Edward M.
Surgery
Truss
Pad
324306, 324309, A61B 505
Patent
active
046026410
ABSTRACT:
A unit volume of moving nuclei is spatially tracked by successive selectively applied NMR rf nutation pulses which solicit NMR spin-echo responses from the tracked moving nuclei. For relatively fast moving nuclei, the NMR responses will come only from the successfully tracked moving nuclei. For relatively slowly moving nuclei (where some stationary nuclei in the overlap of selective excitation regions may also be excited to give NMR responses) and/or even for faster moving nuclei, controlled de-phasing/re-phasing magnetic gradients can be applied before and after a 180.degree. rf nutation pulse so as to effectively phase-encode the spin echo response with respect to only those nuclei having velocity. The same NMR excitation/response sequence is repeated a number of times using different de-phasing/re-phasing magnetic gradients and the velocity of the nuclei may then be derived by regression analysis. A succession of such sequences is used to generate a succession of spin-echo signals having intensity and/or phase parameters which may be two-dimensionally transformed or otherwise processed to provide an NMR image of only the moving nuclei which may be quantitatively analyzed for fluid flow parameters. In the case of pulsatile fluid flows (i.e. such as with arterial blood flow in the human body) the NMR excitation/response sequences are synchronized so as to begin each repetition thereof at a predetermined portion of the pulsatile flow cycle.
REFERENCES:
patent: 3551794 (1970-12-01), Heyden et al.
patent: 4205687 (1980-06-01), White et al.
patent: 4471305 (1984-09-01), Crooks et al.
patent: 4484138 (1984-11-01), Bottomley et al.
patent: 4516582 (1985-05-01), Redington
patent: 4532473 (1985-07-01), Wehrli
Singer, "NMR Flow Imaging", Proceedings of an International Symposium on Nuclear Magnetic Resonance Imaging, Oct. 1-3, 1981, pp. 185-190.
Singer, "NMR Diffusion and Flow Measurements and an Introduction to Spin Phase Graphing", The Institute of Physics, 1978, pp. 281-291.
Lucas et al, "Measurement of Fluid Flow Profiles Using Pulsed NMR", Journal of Physics E: Scientific Instruments, vol. 10, No. 11, 1977, pp. 1150-1152.
Halbach et al, "The NMR Blood Flowmeter-Design", Med. Phys., vol. 8, No. 4, Jul./Aug. 1981, pp. 444-451.
Heinzerling, "Technological Advances in NMR Tomography", Roentgenstrahlen, vol. 49, 1983, pp. 34-41.
Coven Edward M.
Smith Ruth S.
The Regents of the University of California
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