Correction of heart motion due to respiration in clinical myocardial perfusion SPECT scans using respiratory gating
Correction of heart motion due to respiration in clinical myocardial perfusion SPECT scans using respiratory gating
复制标题
DOI：
10.2967/jnumed.106.037390
复制
发表时间：
2007-04-01
影响因子：
9.3
通讯作者：
Azhari, Haim
中科院分区：
文献类型：
--
作者：
Kovalski, Gil;Israel, Ora;Azhari, Haim
一些研究描述了呼吸导致的心肌灌注成像（MPI）不均匀模糊。本文介绍了一种校正呼吸效应的技术，并评估了其在临床研究中的有效性。方法：本研究使用模拟体模、物理体模和患者扫描。使用来回振荡的心脏模型来模拟呼吸。运动是在伽马相机上测量的，该相机支持与外部呼吸带或电阻传感器同步的列表模式功能。使用 1-d(99m)Tc-sestamibi 协议进行八次临床扫描，同时记录呼吸信号。列表模式功能与带子或传感器信号一起用于生成呼吸箱投影集。使用分割过程来检测呼吸箱之间的移动。该偏移被进一步投影到采集的投影图像上以校正呼吸运动。该过程应用于体模和患者研究，并使用传统的牛眼图评估校正的成功率。结果：该算法为模型研究提供了良好的校正。通过拟合椭球测量的校正后的轴向位移 < 1 mm。临床研究中呼吸引起的平均轴向运动为 9.1 毫米。校正后，呼吸相位之间的平均偏移减少至 0.5 毫米。校正后临床扫描牛眼图的最大变化为 6%，平均值为 3.75%。与呼吸校正前的图像相比，校正后的临床总结灌注图像更加均匀、一致，并且对于某些患者来说具有临床意义。结论：MPI SPECT 期间呼吸产生的心肌运动影响灌注图像质量和准确性。可以使用所提出的方法来校正呼吸引起的运动。校正程度取决于患者的呼吸模式，并且在某些情况下可能具有临床意义。
Several studies have described nonuniform blurring of myocardial perfusion imaging (MPI) due to respiration. This article describes a technique for correcting the respiration effect and assesses its effectiveness in clinical studies. Methods: Simulated phantoms, physical phantoms, and patient scans were used in this study. A heart phantom, which oscillated back and forth, was used to simulate respiration. The motion was measured on a gamma-camera supporting list-mode functionality synchronized with an external respiratory strap or resistor sensor. Eight clinical scans were performed using a 1-d(99m)Tc-sestamibi protocol while recording the respiratory signal. The list-mode capability along with the strap or sensor signals was used to generate respiratory bin projection sets. A segmentation process was used to detect the shift between the respiratory bins. This shift was further projected to the acquired projection images for correction of the respiratory motion. The process was applied to the phantom and patient studies, and the rate of success of the correction was assessed using the conventional bull's eye maps. Results: The algorithm provided a good correction for the phantom studies. The shift after the correction, measured by a fitted ellipsoid, was < 1 mm in the axial direction. The average motion due to respiration in the clinical studies was 9.1 mm in the axial direction. The average shift between the respiratory phases was reduced to 0.5 mm after correction. The maximal change in the bull's eye map for the clinical scans after the correction was 6%, with a mean of 3.75%. The postcorrection clinical summed perfusion images were more uniform, consistent, and, for some patients, clinically significant when compared with the images before correction for respiration. Conclusion: Myocardial motion generated by respiration during MPI SPECT affects perfusion image quality and accuracy. Motion introduced by respiration can be corrected using the proposed method. The degree of correction depends on the patient respiratory pattern and can be of clinical significance in certain cases.