摘要
During the process of magnetic resonance imaging (MRI), the patient motion causes phase errors in collected signals and induces motion artifacts in the reconstructed image. Severe artifacts interfere with the focus location. Because the genetic algorithm (GA) has characteristics of parallel, random and adaptive stochastic searching, a correction method of motion artifacts is presented based on the algorithm. The method can correct the phase error in K-space signals step by step. Experiments show that the motion artifacts in MRI can be effectively suppressed by using the method.
磁共振成像过程中,患者的轻微运动就会使扫描数据发生相位偏移,从而使重建图像含有运动伪影,降低成像的质量。严重的伪影会影响医生对病灶的精确定位。本文利用遗传算法高度并行、随机和自适应全局寻优的特点,提出了基于遗传算法的刚性平移运动伪影修正方法,逐次修正扫描信号在K空间中已偏移的相位。实验表明,基于遗传算法的修正方法,能有效校正扫描数据的相位偏移,达到抑制运动伪影的目的。
基金
国家基础研究"九七三"计划(2003CB716102)资助项目~~