Nuclear Medicine Division, Department of Radiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
Epilepsy Behav. 2013 Nov;29(2):386-9. doi: 10.1016/j.yebeh.2013.08.017. Epub 2013 Sep 26.
Bilateral temporal lobe hypometabolism (BTH) on (18)F-FDG PET brain scan is frequently seen in unilateral medial temporal lobe epilepsy (mTLE). This study aimed to identify the factors that influence BTH in patients with mTLE in order to minimize the significant factor(s) prior to performing a FDG-PET brain scan. Forty patients with unilateral mTLE who underwent (18)F-FDG PET scan for presurgical epilepsy workup were included. Bilateral temporal lobe hypometabolism of the anterior and medial parts of the temporal lobe was identified by a semiquantitative visual scale. Lateralization of TLE was identified by either intracranial EEG (22/40 cases) and/or improvement of seizure 2 years after temporal lobectomy (37/40 cases). The factors analyzed included basic demographic characteristics (age, sex, occupation, years of education, and handedness), history related to seizure (age at epilepsy onset and epilepsy duration, history of febrile seizure and head injury, frequency of seizure with impaired cognition in the last 3 months, presence of secondarily generalized tonic-clonic seizure, automatism side, presence of postictal confusion, and side of MRI temporal abnormality), information during video-EEG monitoring (clinical lateralization, interictal scalp EEG lateralization (interictal epileptiform discharge), and ictal scalp EEG lateralization), and information during the FDG-PET study (duration from the last seizure (≤2 days or >2 days), last seizure type, and the presence of slow waves or sharp waves during the FDG uptake period). Significant factors related to BTH were analyzed using multivariate analysis. Only the ≤2-day duration from the last seizure to the PET scan shows a significant effect (p=0.021) on BTH finding with 15 times greater incidence compared to a duration >2 days. Bilateral temporal lobe hypometabolism, which causes conflict in lateralizing the epileptogenic zone in temporal lobe epilepsy, can be avoided by performing PET scan more than 2 days after the last seizure.
双侧颞叶代谢低下（BTH）在单侧内侧颞叶癫痫（mTLE）的（18）F-FDG PET 脑扫描中经常出现。本研究旨在确定影响 mTLE 患者 BTH 的因素，以便在进行 FDG-PET 脑扫描之前，尽量减少显著因素。40 例单侧 mTLE 患者接受了（18）F-FDG PET 扫描，用于术前癫痫评估。通过半定量视觉量表确定颞叶前部和内侧部分的双侧颞叶代谢低下。通过颅内 EEG（22/40 例）和/或颞叶切除术 2 年后癫痫发作改善（37/40 例）确定 TLE 的偏侧化。分析的因素包括基本人口统计学特征（年龄、性别、职业、受教育年限和利手）、与癫痫发作相关的病史（癫痫发作年龄和癫痫持续时间、热性惊厥和头部外伤史、最近 3 个月认知障碍发作的频率、继发性全面强直阵挛发作、自动症侧、发作后意识模糊和 MRI 颞叶异常侧）、视频-EEG 监测期间的信息（临床偏侧化、发作间期头皮 EEG 偏侧化（发作间期癫痫样放电）和发作期头皮 EEG 偏侧化）以及 FDG-PET 研究期间的信息（从最后一次发作到 PET 扫描的时间（≤2 天或>2 天）、最后一次发作类型以及 FDG 摄取期间是否存在慢波或尖波）。使用多变量分析分析与 BTH 相关的显著因素。只有最后一次发作到 PET 扫描的≤2 天时间间隔对 BTH 发现有显著影响（p=0.021），与持续时间>2 天相比，发生率增加了 15 倍。双侧颞叶代谢低下会导致颞叶癫痫致痫区定位冲突，可以通过在最后一次发作后 2 天以上进行 PET 扫描来避免。
