Department of Nuclear Medicine, Isala Hospital, Dokter van Heesweg 2, 8025AB, Zwolle, Netherlands.
Department of Medical Physics, Isala Hospital, Zwolle, Netherlands.
Ann Nucl Med. 2022 Aug;36(8):756-764. doi: 10.1007/s12149-022-01758-0. Epub 2022 Jun 21.
Digital PET systems (dPET) improve lesion detectability as compared to PET systems with conventional photomultiplier tubes (cPET). We prospectively studied the performance of high-resolution digital PET scans in patients with cancer, as compared with high- and standard-resolution conventional PET scans, taking the acquisition order into account.
We included 212 patients with cancer, who were referred for disease staging or restaging. All patients underwent FDG-PET/CT on a dPET scanner and on a cPET scanner in a randomized order. The scans were acquired immediately after each other. Three image reconstructions were generated: 1) standard-resolution (4 × 4 × 4 mm voxels) cPET, 2) high-resolution (2 × 2 × 2 mm voxels) cPET, and 3) high-resolution dPET. Two experienced PET readers visually assessed the three reconstructions side-by-side and ranked them according to scan preference, in an independent and blinded fashion.
On high-resolution dPET, the PET readers detected more lesions or they had a higher diagnostic confidence than on high- and standard-resolution cPET (p < 0.001). High-resolution dPET was preferred in 90% of the cases, as compared to 44% for high-resolution cPET and 1% for standard-resolution cPET (p < 0.001). However, for the subgroup of patients where dPET was made first (n = 103, 61 ± 10 min after FDG administration) and cPET was made second (93 ± 15 min after FDG administration), no significant difference in preference was found between the high-resolution cPET and dPET reconstructions (p = 0.41).
DPET scanners in combination with high-resolution reconstructions clinically outperform cPET scanners with both high- and standard-resolution reconstructions as the PET readers identified more FDG-avid lesions, their diagnostic confidence was increased, and they visually preferred dPET. However, when dPET was made first, high-resolution dPET and high-resolution cPET showed similar performance, indicating the positive effect of a prolonged FDG uptake time. Therefore, high-resolution cPET in combination with a prolonged FDG uptake time can be considered as an alternative.
与配备传统光电倍增管（cPET）的 PET 系统相比，数字 PET 系统（dPET）可提高病灶的可探测性。我们前瞻性地研究了高分辨率数字 PET 扫描在癌症患者中的性能，同时考虑了采集顺序，并与高分辨率和标准分辨率的传统 PET 扫描进行了比较。
我们纳入了 212 名癌症患者，这些患者被转诊进行疾病分期或再分期。所有患者均在 dPET 扫描仪和 cPET 扫描仪上随机进行 FDG-PET/CT 检查。扫描是紧接着进行的。生成了 3 种图像重建：1）标准分辨率（4×4×4mm 体素）cPET，2）高分辨率（2×2×2mm 体素）cPET，和 3）高分辨率 dPET。两位有经验的 PET 读者并排查看了这 3 种重建，并以独立和盲法的方式根据扫描偏好进行了排序。
在高分辨率 dPET 上，与高分辨率和标准分辨率 cPET 相比，PET 读者检测到的病灶更多，或更有诊断信心（p＜0.001）。高分辨率 dPET 在 90%的情况下更受青睐，而高分辨率 cPET 为 44%，标准分辨率 cPET 为 1%（p＜0.001）。然而，对于首先进行 dPET（n=103，在 FDG 给药后 61±10 分钟）且其次进行 cPET（在 FDG 给药后 93±15 分钟）的患者亚组，高分辨率 cPET 和 dPET 重建之间的偏好没有显著差异（p=0.41）。
dPET 扫描仪与高分辨率重建相结合在临床上优于配备高分辨率和标准分辨率重建的 cPET 扫描仪，因为 PET 读者识别出更多的 FDG 摄取病灶，他们的诊断信心增强，并且更倾向于 dPET。然而，当首先进行 dPET 时，高分辨率 dPET 和高分辨率 cPET 表现出相似的性能，表明 FDG 摄取时间延长的积极影响。因此，高分辨率 cPET 结合延长的 FDG 摄取时间可以被视为一种替代方案。
