局灶性脑皮质发育不良的MRI表现及分型

MRI Findings and Classification of Focal Cortical Dysplasia

目的研究局灶性脑皮质发育不良(FCD)的MRI分型及其表现特点。资料与方法收集经手术病理证实的54例FCD患者,回顾性分析其MRI表现。观察病变部位、皮质厚度、灰白质界限、白质信号及脑回和脑沟形态。分析病变区信号变化和皮质厚度,对FCD的MRI表现进行分型。结果 FCD的MR影像表现可分为3型:放射带型、高信号型及轻微型。放射带型10例,表现为皮质/皮质下T2WI/液体衰减反转恢复序列(FLAIR)高信号,白质内异常信号从皮质向侧脑室延伸;高信号型25例,表现为皮质/皮质下片状T2WI/FLAIR高信号,皮质增厚,但无放射带;轻微型19例,表现为无皮质下高信号,皮质T2WI/FLAIR轻微高信号,皮质增厚。结论 FCD的病变表现多样,可分为放射带型、高信号型及轻微型3种类型,FCD的影像分型有助于其影像诊断和认识。

Purpose To analyze the MRI findings and imaging classification of focal cortical dysplasia （FCD）. Materials and Methods MR images of 54 patients with pathologic confirmed FCD were included in this study. Lesion location, cortex thickness, the gray/white matter junction, subcortical white matter signal intensity, and morphology of gyri and sulci of the patients were evaluated retrospectively. Results MRI appearances of FCD were divided into three subtypes： radial band-, hyperintensity- and mild- type FCD. MR images showed radial band type in 10, hyperintensity type in 25, and mild type in 19 patients, respectively. Radial band FCD showed a tail of increased T2/FLAIR signal tapering down to the lateral ventricle. Hyperintensity type FCD displayed increased T2/FLAIR signal in the region of FCD, 21 patients with focal cortical thickening. Mild FCD showed subtle hyperintense signal in the cortex with focal cortical thickening on T2/FLAIR, but no hyperintense signal in subcortical white matter area. Conclusion The MR appearances of FCD are variable. Understanding the MR imaging type of FCD might improve the MR diagnosis of FCD.