PET/CT成像呼吸运动B样条校正

摘要

The degradation of image quality of PET/CT caused by respiratory motion will affect the physician’s diagnosis. The common developed technology of respiratory motion correction is gating, but it still has some limitations. This paper proposes a new method that using CT images extract the features of respiratory motion based on B-Spline to correct respi-ration. Firstly, it obtains the sequence of CT images corresponding with PET images within same respiratory motion cycle, and extracts the features of the motion of CT sequences within respiratory cycle by B-Spline. Next it transforms the feature parameters of CT sequences into the corresponding PET image sequences for the motion correction. The geometric defor-mation phantom and voxelised phantom tests show that the proposed method can obviously improve the quality of image of PET/CT for respiratory motion, and has a value of study further.%PET/CT成像中的人体呼吸运动会造成图像运动模糊，会严重影响图像质量，对医生的诊断造成影响。目前常用的呼吸门控技术能够在一定程度上改善图像质量，但是均存在其局限性。提出了一种基于CT图像提取呼吸运动特征的B样条方法，对呼吸运动图像进行校正。在PET/CT上获取与PET图像周期匹配的CT图像序列，通过B样条配准方式对在呼吸周期内的CT图序列像提取运动信息；对CT图像所匹配的PET图像做基于运动特征信息的校正变换进行运动校正。几何位移形变和像素人体模实验结果表明，提出的方法对PET/CT呼吸运动图像质量改进明显，具有研究价值。