Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Epilepsy Res. 2010 Feb;88(2-3):247-54. doi: 10.1016/j.eplepsyres.2009.12.002. Epub 2010 Jan 25.
Ictal Single Proton Emission Computed Tomography (SPECT) has demonstrated high levels of sensitivity in localizing seizures among patients with epilepsy of the mesial temporal lobe (mTLE). However, incorrect information on the lateralization of mTLE has also been reported. In order to investigate the causes of these incorrect localizations, the authors assessed clinical symptoms, as well as the electroencephalography (EEG) and brain SPECT scan data of five patients with mTLE experiencing ictal hyperperfusion of the contralateral temporal lobe. All patients underwent presurgical evaluations, including an interictal and ictal brain SPECT scan. A subtraction ictal SPECT co-registered with Magnetic Resonance Imaging (MRI) procedure or SISCOM was performed. Hyperperfusion (ictal perfusion greater than interictal perfusion) and hypoperfusion (ictal perfusion lower than interictal perfusion), results of SISCOM were analyzed and compared with seizure and ictal EEG pattern patterns. All the five patients had unilateral hippocampal sclerosis, and the radiotracer for the ictal SPECT was injected after the ictal EEG pattern had propagated to the contralateral side. The average delay between the ictal EEG onset and the radiotracer injection was 29.7+/-9.6s. All hyperperfusion SISCOM results revealed hyperperfusion in the contralateral temporal region with a more intense ictal EEG build-up. However, hypoperfusion SISCOM results demonstrated significant hypoperfusion in the epileptogenic temporal lobe of three of the five patients, but no hypoperfusion finding in the other two patients. This study demonstrates that early ictal EEG pattern propagation to the contralateral side in mTLE may be associated with contralateral ictal hyperperfusion with or without ipsilateral temporal hypoperfusion. The authors recommend simultaneous interpretations of ictal SPECT and ictal EEG propagation patterns at the time of the injection of radiotracers.
发作期单光子发射计算机断层扫描（SPECT）已证明在定位内侧颞叶（mTLE）癫痫患者的癫痫发作方面具有很高的敏感性。然而，也有报道称 mTLE 的侧化信息不正确。为了研究这些不正确定位的原因，作者评估了 5 例 mTLE 患者的临床症状以及脑电图（EEG）和脑 SPECT 扫描数据，这些患者在对侧颞叶出现发作期过度灌注。所有患者均接受了术前评估，包括发作间期和发作期脑 SPECT 扫描。进行了发作期 SPECT 减影与磁共振成像（MRI）或 SISCOM 配准。分析并比较了 SISCOM 的过度灌注（发作期灌注大于发作间期灌注）和灌注不足（发作期灌注低于发作间期灌注）结果与发作和发作期 EEG 模式。所有 5 例患者均存在单侧海马硬化，放射性示踪剂在发作期 EEG 模式传播到对侧后进行注射。发作期 EEG 起始与放射性示踪剂注射之间的平均延迟时间为 29.7+/-9.6s。所有过度灌注 SISCOM 结果均显示对侧颞叶区域出现过度灌注，伴有更强烈的发作期 EEG 增强。然而，在 5 例患者中的 3 例，SISCOM 结果显示发作性癫痫病灶颞叶存在显著灌注不足，但在另外 2 例患者中未发现灌注不足。这项研究表明，mTLE 中早期发作期 EEG 模式向对侧传播可能与对侧发作期过度灌注伴或不伴同侧颞叶灌注不足有关。作者建议在放射性示踪剂注射时同时解释发作期 SPECT 和发作期 EEG 传播模式。
