| 摘要 |
PROBLEM TO BE SOLVED: To measure the phase shift of succeeding echoes by the influence of an eddy current and residual magnetization due to a preceding encoding gradient or the like by a method of linearly Fourier transforming data gathered from the echo and obtaining a phase shift amount by the influence of an encoding gradient based on obtained phase data. SOLUTION: The initial value of the amplitude agyp1i of pulses gyp1i for compensation in the pulse sequence of prescanning is set to an appropriate value (S1). Then, in the case that the polarity of the encoding gradient gy is positive or in the case that it is negative, by the respective pulse sequences of prescanning, the data are respectively gathered from echoes echo'1 and echo'2 of a second half (S2). Then, the respective data obtained from the echoes echo'1 and echo'2 are linearly Fourier transformed, the phase data of the result are fitted by using the method of least squares or the like and the respective first order di1 and di2 and zero-order terms BOi1 and BOi2 of the result are obtained (S3). Further, a first-order phase shift amountϕi<+> is obtained (S4).
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