致痫性局灶性脑皮层发育不良患者的PET—CT与MRI研究

PET- CT and MRI research on epileptogenic focal cortical dysplasia

目的研究致痫性局灶性脑皮层发育不良（FCD）的PET-CT与MRI检查特点，评价其在癫痫外科术前致痫灶定位诊断中的应用价值。方法回顾性分析2009年1月至2011年10月珠江医院神经外科癫痫病灶切除术后病理证实为FCD患者临床资料，总结其中39例资料完整患者的病灶分布、病理亚型、MRI及PET-CT影像特点、预后等指标，分析各指标间的相互关系。结果本组MRI阳性31例，主要表现为灰白质交界不清、局部皮层增厚和形态异常、T2WI与Flair像上白质信号增高等特点。其中T2、Flair高信号在FCDIIb型非常常见，而FCDI型则鲜有表现。PET-CT病灶阳性表现36例，略高于MRI阳性率。按照Engel预后分级法，本组Ⅰ级74％（29／39），Ⅱ级18％（7／39），Ⅲ级5％（2／39），Ⅳ级3％（1／39）。结论在致痫性FCD病例中，MRI主要表现为灰白质交界不清、局部皮层增厚和形态异常、T2WI与Flair像上白质信号增高等特点。PET-cT检查可提高单纯MRI检查的准确性。

Objective To investigate the PET - CT and MR imaging characteristics of patients with epileptogenic focal cortical dysplasia, and to evaluate their values in the foci localization of preoperative epilepsy surgery. Methods A retrospective analysis of the clinical data of patients with epileptogenic focal cortical dysplasia, resection of the epileptic focus, and confirmed pathologically in Zhujiang hospital, was carried out from January 2009 to October 2011. The data as distribution of the lesions, histologic subtypes, and MR and PET imaging characteristics and prognosis of 39 patients having complete data were concluded. The relations between each two indexes were analyzed. Results MR imaging showed positive lesions in 31 patients, mainly manifested as unclear junctions between the gray and white matter, local cortical thickening and abnormal morphology, and increased white matter signal on T2WI and Flair imaging. In high signals of T2WI, Flair imaging was very common in patients with the FCD Ⅱ b subtype, while rare in patients with the FCD Ⅰ b subtype. PET - CT showed positive lesions in 36 patients; the detection rate was slightly higher than that of MR imaging. According to the Engel prognosis grading, 74% （29/39）of patients was in grade Ⅰ, 18% （7/39） in grade Ⅱ, 5% （2/39） in grade Ⅲ, and 3% （1/39） in grade Ⅳ. Conclusion In patients with epileptogenie focal cortical dysplasia, unclear junctions between the gray and white matter, local cortical thickening and abnormal morphology, and increased white matter signal on T2WI, and Flair imaging are the main manifestations in MR imaging; PET - CT combined with MR imaging can improve the accuracy of detection.