Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, 5-4-1 Shimorenjaku, Mitaka-shi, Tokyo, 181-8612, Japan.
Department of Medical Quantum Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka-shi, Japan.
Radiol Phys Technol. 2023 Sep;16(3):397-405. doi: 10.1007/s12194-023-00730-5. Epub 2023 Jun 29.
Compressed sensing (CS) has been used to improve image quality in single-photon emission tomography (SPECT) imaging. However, the effects of CS on image quality parameters in myocardial perfusion imaging (MPI) have not been investigated in detail. This preliminary study aimed to compare the performance of CS-iterative reconstruction (CS-IR) with filtered back-projection (FBP) and maximum likelihood expectation maximization (ML-EM) on their ability to reduce the acquisition time of MPI. A digital phantom that mimicked the left ventricular myocardium was created. Projection images with 120 and 30 directions (360°), and with 60 and 15 directions (180°) were generated. The SPECT images were reconstructed using FBP, ML-EM, and CS-IR. The coefficient of variation (CV) for the uniformity of myocardial accumulation, septal wall thickness, and contrast ratio (Contrast) of the defect/normal lateral wall were calculated for evaluation. The simulation was performed ten times. The CV of CS-IR was lower than that of FBP and ML-EM in both 360° and 180° acquisitions. The septal wall thickness of CS-IR at the 360° acquisition was inferior to that of ML-EM, with a difference of 2.5 mm. Contrast did not differ between ML-EM and CS-IR for the 360° and 180° acquisitions. The CV for the quarter-acquisition time in CS-IR was lower than that for the full-acquisition time in the other reconstruction methods. CS-IR has the potential to reduce the acquisition time of MPI.
压缩感知 (CS) 已被用于提高单光子发射断层扫描 (SPECT) 成像的图像质量。然而，CS 对心肌灌注成像 (MPI) 中图像质量参数的影响尚未得到详细研究。本初步研究旨在比较 CS-迭代重建 (CS-IR) 与滤波反投影 (FBP) 和最大似然期望最大化 (ML-EM) 在减少 MPI 采集时间方面的性能。创建了一个模拟左心室心肌的数字体模。生成了具有 120 和 30 个方向（360°）以及 60 和 15 个方向（180°）的投影图像。使用 FBP、ML-EM 和 CS-IR 重建 SPECT 图像。计算心肌累积均匀性、室间隔厚度和缺陷/正常侧壁对比度（Contrast）的变异系数 (CV) 进行评估。模拟进行了十次。在 360°和 180°采集时，CS-IR 的 CV 均低于 FBP 和 ML-EM。360°采集时 CS-IR 的室间隔厚度不如 ML-EM，相差 2.5 毫米。360°和 180°采集时，ML-EM 和 CS-IR 之间的对比度没有差异。CS-IR 在四分之一采集时间的 CV 低于其他重建方法在全采集时间的 CV。CS-IR 有可能减少 MPI 的采集时间。
