【摘要】 利用自制的微成象系统，在7T的主磁场下，测量了模型样品的核磁共振图象中磁化率引起的失真。观察到图象的失真随频率编码梯度场强度的增大而减弱，对不同的成象脉冲序列，场梯度回波序列所产生的失真最大，自旋回波序列其次，双相位编码的脉冲序列则能完全消除磁化率效应引起的失真。更多还原

【Abstract】 Using a home made microimage system, we studied the susceptibility effect in magnetic resonance image of a model sample under 7 T main field. The distortion due to the susceptibility effect of the sample was decreased as the increasing of the strength of the frequency encoding gradient. For different imaging pulse sequences, the gradient echo sequence has a bigest distortion, and then the spin echo sequence. The double phase encoding sequence can totally eliminate the distortion due to the susceptibility effect.更多还原