目的:结节性硬化症(TSC)患者约有60%的病例出现耐药性癫痫,和评估癫痫手术可能是必要的。在MRI上对多个发育不良病变中的癫痫发生区(EZ)的正确描绘代表了术前评估的挑战性步骤。
方法:两位经验丰富的神经放射科医师评估了28例TSC癫痫手术患者的手术前和手术后的MRI,评估块茎的特征,囊肿,钙化,和局灶性皮质发育不良(FCD)相似的病变。利用多个指标,我们比较了在癫痫手术后2年实现无癫痫发作的TSC患者的EZ定义为切除区域的MRI特征与其他脑区的特征.使用组合分析,我们确定了在TSC患者的癫痫发生区最常见的发育不良特征组合.
结果:所有与TSC相关的发育不良特征在EZ中比在其他大脑区域更常见(皮质厚度增加,灰白色物质模糊,Transmantle标志,钙化,和块茎;肯德尔的tau分别为0.35、0.25、0.27、0.26和0.23;全部P值<.001)。没有一个单一的特征能够可靠且独立地指示所有患者的EZ。相反,EZ由以下三个特征的组合表示:块茎,Transmantle标志,皮质厚度增加,钙化,以及受FCD影响最大的地区。在这些中,最大的FCD影响区域成为EZ最可靠的指标,结合钙化或块茎。
结论:TSC患者的癫痫发生区具有多种发育不良特征,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TSC癫痫手术候选者的术前MRI评估。
OBJECTIVE: 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.
METHODS: 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.
RESULTS: 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.
CONCLUSIONS: 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.