Department of Diagnostic Radiology, Princess Alexandra Hospital, Brisbane, Queensland, Australia.
Biomedical Technology Services, Princess Alexandra Hospital, Brisbane, Queensland, Australia.
J Med Imaging Radiat Oncol. 2020 Apr;64(2):204-210. doi: 10.1111/1754-9485.13000. Epub 2020 Feb 9.
This study aims to evaluate discrepant findings between positron emission tomography/magnetic resonance imaging (PET/MRI) and positron emission tomography/computed tomography (PET/CT) in a cohort of oncological patients and to undertake a phantom study to assess the potential for extended PET acquisitions to lead to false-positive findings on PET/MRI.
Discrepant findings from a series of 106 patients undergoing same-day F-fluorodeoxyglucose (FDG)-PET/CT and PET/MRI were reviewed. Phantom studies explored the potential for PET acquisition time to contribute to discrepancy.
There were 14 discrepant cases, 5 (35.7%) of which related to PET/MRI acquisitions that had been extended to 10 min. Three of these five cases proved to be falsely positive. Phantom studies showed greater contrast recovery and signal to noise ratio for 10-min PET/MRI acquisitions compared to 2-min acquisitions using PET/CT. There were no discrepancies when PET/CT showed disseminated disease (P = 0.036).
Extended PET/MRI acquisitions used to accommodate multiple MRI sequences may be associated with false-positive findings compared to PET/CT. PET/MRI is more likely to have incremental value when the prior probability for disseminated disease is low.
本研究旨在评估在一组肿瘤患者中，正电子发射断层扫描/磁共振成像（PET/MRI）与正电子发射断层扫描/计算机断层扫描（PET/CT）之间的不一致发现，并进行一项体模研究，以评估延长 PET 采集时间是否会导致 PET/MRI 出现假阳性结果。
回顾了 106 例同一天进行 F-氟脱氧葡萄糖（FDG）-PET/CT 和 PET/MRI 的患者系列中出现的不一致发现。体模研究探讨了 PET 采集时间对差异的潜在影响。
有 14 例不一致的病例，其中 5 例（35.7%）与延长至 10 分钟的 PET/MRI 采集有关。这 5 例中有 3 例被证实为假阳性。体模研究显示，与使用 PET/CT 的 2 分钟采集相比，10 分钟 PET/MRI 采集具有更高的对比度恢复和信噪比。当 PET/CT 显示弥散性疾病时，没有差异（P=0.036）。
与 PET/CT 相比，用于适应多个 MRI 序列的延长 PET/MRI 采集可能与假阳性结果有关。当弥散性疾病的先验概率较低时，PET/MRI 更有可能具有增量价值。
