MR T_1 WI纹状体高信号表现分析

The Evaluation of MR T_1 WI Hyperintensity in Corpus Striatum

目的探讨纹状体MRT1WI高信号病变的影像表现,并结合文献讨论其发生机制及病理改变。资料与方法回顾性分析32例纹状体MRT1WI高信号病变的影像表现,包括亚临床性肝性脑病,钙化、脑梗死及CO中毒性脑病。结果亚临床性肝性脑病患者表现为多个部位的T1WI高信号,主要累及部位有苍白球,壳核,中脑红核周围,T2WI及CT上未见异常,T2WI梯度回波上呈明显或较低信号;钙化表现为纹状体对称的T1WI高信号,其信号强度不均匀,T2WI上表现为稍低、等或高信号,CT表现为高密度;脑梗死后病变表现为纹状体点片状T1WI高信号,T2WI上可见比T1WI上范围大的高信号;CO中毒性脑病表现为双侧纹状体对称性T1WI高信号,其信号强度不均匀,主要累及苍白球,T2WI上其周围深部白质可见大片状高信号。结论纹状体T1WI高信号主要与金属顺磁性物质(锰、钙、铁等)的沉积有关。结合临床表现及实验室检查可以做出正确地诊断与鉴别诊断。

Objective To discuss the MR features of the MR T1WI hyperintensity in corpus striatum and its pathogenesis and pathological changes. Materials and Methods The imaging data of 32 MR T1 WI hyperintensity lesions in corpus striatum were retrospectively evaluated, including subclinical hepatic encephalopathy（SHE）, calcification, cerebral infarction and CO poisoned encephalopathy. Results SHE was demonstrated as hyperintensity in the globus pallidus, putamen and mesencephalon surrounding red nucleus on T1WI, the T2WI and CT were normal. The T2 FE showed hypointensity. The calcification represented symmetric hyperintensity on T1W in corpus striatum, which was hypointensity and hyperdensity on T2WI and CT respectively. The cerebral infarction was patchy T1WI hyperintensity in corpus striatum and larger hyperintensity on T2WI. The CO poisoned encephalopathy showed bilateral symmetric hyperintensity in corpus striatum, mainly involved globus pallidus with diffused T2WI hyperintensity lesions in white matter. Conclusion The T1WI hyperintensity in corpus striatum is mainly related with the deposition of paramagnetic metal. Combined with clinic data, MRI can make correct diagnosis and differential diagnosis.