Department of Neurology, Royal Melbourne Hospital, Parkville, VIC, Australia.
Department of Medicine and Radiology, University of Melbourne, Parkville, VIC, Australia.
Brain Imaging Behav. 2021 Dec;15(6):2795-2803. doi: 10.1007/s11682-021-00576-8. Epub 2021 Oct 20.
A high proportion of patients with drug-resistant temporal lobe epilepsy (TLE) show focal relative hypometabolism in the region of the epileptogenic zone on [F]-Fluorodeoxyglucose positron emission tomography (FDG PET). However, whether focal (hypo)metabolism changes over time has not been well studied. We analysed repeated [F]-FDG PET scans of patients with TLE to determine longitudinal changes in glucose metabolism. Adults (n = 16; 9 female, 7 male) diagnosed with drug resistant chronic TLE were assessed. Each patient had two [F]-FDG PET scans that were 2-95 months apart. Region-of-interest analysis was performed on MR images onto which PET scans were coregistered to determine the relative [F]-FDG uptake (normalised to pons) in the bilateral hippocampi and temporal lobes. Statistical Parametric Mapping analysis investigated global voxel-wise changes in relative metabolism between timepoints. Normalised [F]-FDG uptake did not change with time in the ipsilateral (baseline 1.14 ± 0.03, follow-up 1.19 ± -0.04) or contralateral hippocampus (baseline 1.18 ± 0.03, follow-up 1.19 ± 0.03). Uptake in the temporal neocortex also remained stable (ipsilateral baseline 1.35 ± 0.03, follow-up 1.30 ± 0.04; contralateral baseline 1.38 ± 0.04, follow-up 1.33 ± 0.03). The was no relationship between change in uptake on the repeated scans and the time between the scans. SPM analysis showed increases in metabolism in the ipsilateral temporal lobe in 2/16 patients. No areas of decreased metabolism concordant to the epileptogenic zone were identified. [F]-FDG uptake showed no significant changes over time in patients with drug-resistant TLE. This suggests that repeating FDG-PET scans in patients with subtle or no hypometabolism is of low clinical yield.
在 [F]-氟脱氧葡萄糖正电子发射断层扫描（FDG PET）中，耐药性颞叶癫痫（TLE）患者中有很大一部分表现为致痫区的局灶性相对低代谢。然而，代谢是否随时间而变化尚未得到很好的研究。我们分析了 TLE 患者的重复 [F]-FDG PET 扫描，以确定葡萄糖代谢的纵向变化。评估了 16 名成年（9 名女性，7 名男性）确诊为耐药性慢性 TLE 的患者。每位患者均进行了两次 [F]-FDG PET 扫描，两次扫描相隔 2-95 个月。将 PET 扫描与磁共振图像配准，在磁共振图像上进行感兴趣区分析，以确定双侧海马和颞叶的相对 [F]-FDG 摄取（以桥脑为标准化）。统计参数映射分析研究了两个时间点之间相对代谢的全局体素变化。在同侧（基线 1.14±0.03，随访 1.19±0.04）或对侧海马（基线 1.18±0.03，随访 1.19±0.03）中，[F]-FDG 摄取均未随时间而变化。颞叶新皮质的摄取也保持稳定（同侧基线 1.35±0.03，随访 1.30±0.04；对侧基线 1.38±0.04，随访 1.33±0.03）。重复扫描中摄取的变化与两次扫描之间的时间没有关系。SPM 分析显示 2/16 名患者的同侧颞叶代谢增加。没有发现与致痫区一致的代谢减少区域。耐药性 TLE 患者的 [F]-FDG 摄取随时间没有显著变化。这表明，在轻微或无低代谢的患者中重复 FDG-PET 扫描临床获益较低。
