MELAS综合征的影像学特点

The imaging characteristics of MELAS syndrome

目的:探讨MELAS综合征影像学特点及诊断价值。方法:回顾性分析6例MELAS综合征的临床、影像学及肌肉病理资料。结果:3例颅脑CT未发现钙化。10次卒中样发作颅脑MRI发作期常规T1、T2加权相表现为颞顶枕叶皮质及皮质下白质长T1、T2异常信号,2例弥散加权成像表现为相应部位脑回样高信号。恢复期受累部位表现为局限性萎缩,可显示典型层状坏死。5例患者肌肉Gomori染色可见典型的破碎红边纤维。结论:MRI反复颞顶枕叶皮质及皮质下白质病灶可为临床诊断提供帮助,与在脑梗死诊断中的作用类似,弥散加权成像可能会更早地显示病灶。

Objective： To investigate the imaging characteristics of MELAS syndrome and assess the diagnostic value of MRI. Methods： The clinical and imaging findings of 6 patients with MELAS syndrome were analyzed retrospectively. Result： Abnormal calcification on CT was not found in 3 patients. 10 stroke-like episodes presented long T1 long T2 signals in the cortex and subcortical white matter of temporal, parietal, and occipital lobes, and 2 presented high signals in diffusion weighted images in periods of attacks, In convalescent periods, local atrophy and laminar necrosis were showed. Muscle biopsy showed ragged red fibers in 5 patients. Conclusion： Recurrent lesions in the cortex and subcortical white matter of temporal, parietal, and occipital lobe on MRI might provide clues for diagnosis of MELAS syndrome. DWI might show lesions earlier than T2WI in MELAS syndrome similar to cerebral infarction.