Department of Pediatric Neurology, Brain Center University Medical Center Utrecht, Utrecht, The Netherlands.
Department of Pediatric Neurology, Second Faculty of Medicine, Charles University and Motol University Hospital, Prague, Czech Republic.
Epilepsia Open. 2021 Dec;6(4):663-671. doi: 10.1002/epi4.12529. Epub 2021 Aug 6.
Patients with tuberous sclerosis complex (TSC) present with drug-resistant epilepsy in about 60% of cases, and evaluation for epilepsy surgery may be warranted. Correct delineation of the epileptogenic zone (EZ) among multiple dysplastic lesions on MRI represents a challenging step in pre-surgical evaluation.
Two experienced neuroradiologists evaluated pre- and post-surgical MRIs of 28 epilepsy surgery patients with TSC, assessing characteristics of tubers, cysts, calcifications, and focal cortical dysplasia (FCD)-resembling lesions. Utilizing multiple metrics, we compared MRI features of the EZ-defined as the resected area in TSC patients who achieved seizure-freedom 2 years after epilepsy surgery-with features of other brain areas. Using combinatorial analysis, we identified combinations of dysplastic features that are most frequently observed in the epileptogenic zone in TSC patients.
All TSC-associated dysplastic features were more frequently observed in the EZ than in other brain areas (increased cortical thickness, gray-white matter blurring, transmantle sign, calcifications, and tubers; Kendal's tau 0.35, 0.25, 0.27, 0.26, and 0.23, respectively; P value <.001 in all). No single feature could reliably and independently indicate the EZ in all patients. Conversely, the EZ was indicated by the presence of the combination of three of the following features: tubers, transmantle sign, increased cortical thickness, calcifications, and the largest FCD-affected area. Out of these, the largest FCD-affected area emerged as the most reliable indicator of the EZ, combined either with calcifications or tubers.
The epileptogenic zone in TSC patients harbors multiple dysplastic features, consistent with focal cortical dysplasia. A specific combination of these features can indicate the EZ and aid in pre-surgical MRI evaluation in epilepsy surgery candidates with TSC.
约 60%的结节性硬化症（TSC）患者存在耐药性癫痫，可能需要进行癫痫手术评估。在 MRI 上的多个发育不良病变中正确划定致痫区（EZ）是术前评估中的一个具有挑战性的步骤。
两位经验丰富的神经放射科医生评估了 28 例接受 TSC 癫痫手术的患者的术前和术后 MRI，评估了结节、囊肿、钙化和局灶性皮质发育不良（FCD）样病变的特征。利用多种指标，我们比较了 EZ 的 MRI 特征（定义为癫痫手术后 2 年内无癫痫发作的 TSC 患者的切除区域）与其他脑区的特征。利用组合分析，我们确定了在 TSC 患者致痫区中最常观察到的发育不良特征的组合。
与其他脑区相比，所有与 TSC 相关的发育不良特征在 EZ 中更为常见（皮质增厚、灰白质模糊、脑膜穿透征、钙化和结节；Kendall 的 tau 值分别为 0.35、0.25、0.27、0.26 和 0.23；所有 P 值均<0.001）。没有单一特征可以在所有患者中可靠且独立地指示 EZ。相反，EZ 由以下三种特征的组合来指示：结节、脑膜穿透征、皮质增厚、钙化和受影响的最大 FCD 区域。在这些特征中，最大的 FCD 受影响区域是 EZ 的最可靠指示，与钙化或结节结合使用。
TSC 患者的致痫区存在多种发育不良特征，与局灶性皮质发育不良一致。这些特征的特定组合可以指示 EZ，并有助于术前 MRI 评估 TSC 癫痫手术候选者。
