Department of Medical Radiation Physics, Lund University Sweden. katarina.sjogreen
Phys Med Biol. 2009 Oct 21;54(20):6181-200. doi: 10.1088/0031-9155/54/20/010. Epub 2009 Oct 1.
For radionuclide therapy, individual patient pharmacokinetics can be measured in three dimensions by sequential SPECT imaging. Accurate registration of the time series of images is central for voxel-based calculations of the residence time and absorbed dose. In this work, rigid and non-rigid methods are evaluated for registration of 6-7 SPECT/CT images acquired over a week, in anatomical regions from the head-and-neck region down to the pelvis. A method for calculation of the absorbed dose, including a voxel mass determination from the CT images, is also described. Registration of the SPECT/CT images is based on a CT-derived spatial transformation. Evaluation is focused on the CT registration accuracy, and on its impact on values of residence time and absorbed dose. According to the CT evaluation, the non-rigid method produces a more accurate registration than the rigid one. For images of the residence time and absorbed dose, registration produces a sharpening of the images. For volumes-of-interest, the differences between rigid and non-rigid results are generally small. However, the non-rigid method is more consistent for regions where non-rigid patient movements are likely, such as in the head-neck-shoulder region.
对于放射性核素治疗，可以通过连续的 SPECT 成像在三个维度上测量个体患者的药代动力学。准确注册图像的时间序列对于基于体素的停留时间和吸收剂量计算至关重要。在这项工作中，评估了刚性和非刚性方法，用于注册在一周内从头部和颈部区域到骨盆区域采集的 6-7 个 SPECT/CT 图像。还描述了一种计算吸收剂量的方法，包括从 CT 图像确定体素质量。SPECT/CT 图像的配准基于 CT 衍生的空间变换。评估集中在 CT 配准精度及其对停留时间和吸收剂量值的影响。根据 CT 评估，非刚性方法比刚性方法产生更准确的配准。对于停留时间和吸收剂量图像，配准会使图像锐化。对于感兴趣的体积，刚性和非刚性结果之间的差异通常较小。然而，对于可能发生非刚性患者运动的区域，例如头部、颈部和肩部区域，非刚性方法更一致。
