心肌SPECT灌注显像的心脏轴向移动校正

目的 对SPECT心肌灌注显像中心脏的轴向移动进行校正,以最大限度地降低运动伪影对诊断的影响.方法 通过电影、正弦图和回旋图显示,实现对心脏移动可视的定性评估；通过帧与帧之间的互相关函数方法,找出位移角度,对投影的校正给出建议值；经可视评估后,确定投影移动校正的初值；根据移动校正的初值重建图像,通过对重建图像的投影与采集投影的互信息分析,最后计算出投影移动校正.结果 心肌模型实验表明,本方法能够精确地复现模型的轴向运动,位置误差小于3 mm,经校正后重建图像改善明显.结论 本方法具有客观、精确、可视的优点,可精确确定和校正SPECT心肌灌注显像中心脏的轴向移动.

Correction of cardiac axial movement during myocardial perfusion SPECT imaging

Objective To correct the cardiac axial movement during myocardial perfusion SPECT imaging, in order to reduce the motion-artifact's influence on diagnosis. Methods Visual inspection of motion of the heart was done by means of cine of the raw data, sonogram and cyclogram. By cross-correlation, the camera angles were localized at which the motion occurred and determine the suggested correction for the motion. By means of visual inspection, the correction was modified and verified. Based in the correction at this stage, the images were reconstructed. The final motion correction was then determined by means of maximize the cross-correlation between the projection from the reconstructed image and the measured projection. Results Myocardial phantom showed that the motion of the phantom can be revealed at an accuracy of 3 mm for various kinds of axial motions. Motion artifacts on myocardial perfusion SPECT images were effectively improved. Conclusion This approach can be used to provide non-subjective, accurate, quantitative, and visual means of axial motion correction in myocardial perfusion SPECT imaging.