Title:
MAGNETIC RESONANCE IMAGING METHOD AND SYSTEM
Document Type and Number:
Japanese Patent JPH0213434
Kind Code:
A
Abstract:
PURPOSE: To compensate sprious NMR frequency/phase shift by picking up data in a calibrating measurement cycle and considering the degree of a detected frequency spectrum away from expectation and the degree or relative measured phase of a sampled RF signal away from zero. CONSTITUTION: Complete mutlislice MRI data sampling scan is executed according to the conventional method. However, one excess measuring cycle at least omitting one gradient magnetic pulse at least is included for generating excess comparative data. The calibrating data are used for matching the central frequency of RF transmitter of an MRI system so as to be used during the following measuring cycle. Besides, the calibrating data are sued for adjusting drift and/or residual eddy current generated during the scan of recorded scan data within every measuring cycle of applied scan. This adjustment is performed not only for a timewise area but also for a spatial area. It is executed before the adjustment of the central frequency as needed.
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Inventors:
CHIN YAO
JIEEMUSU DEII HEIRU
ROORENSU II KURUTSUKUSU
JIEEMUSU DEII HEIRU
ROORENSU II KURUTSUKUSU
Application Number:
JP9506489A
Publication Date:
January 17, 1990
Filing Date:
April 14, 1989
Export Citation:
Assignee:
UNIV CALIFORNIA
International Classes:
G01R33/48; G01R33/565; G01R33/58; A61B5/055; (IPC1-7): A61B5/05; A61B5/055; G01N24/08; G01R33/48
Domestic Patent References:
| JPS60236637A | 1985-11-25 | |||
| JPS60193448A | 1985-10-01 | |||
| JPS5934137A | 1984-02-24 |
Attorney, Agent or Firm:
Shoichi Hase (1 person outside)
Next Patent: JPH0213435