可复性后部脑病综合征的影像学诊断

目的探讨可复性后部脑病综合征（PRES）的影像学表现.方法回顾性分析了12例PRES病人的临床和影像学资料,其中9例为子痫/先兆子痫,2例为高血压脑病,1例为环孢菌素A（CSA）的神经毒性.12例均行MRI检查,其中7例同时行钆喷替酸葡甲胺（Gd-DTPA）增强扫描,4例行磁共振血管造影（3D-TOF MRA）检查,1例行弥散加权成像（DWI）.7例行CT平扫检查,2例行脑血管造影（DSA）检查.结果MRI显示病灶基本上呈双侧对称性分布,多数病灶位于顶、枕叶脑实质内,T1WI呈等或略低信号,T2WI呈高信号,FLAIR像显示皮层和皮层下白质明显高信号影,较T1WI、T2WI更加清楚.注射Gd-DTPA后多无明显异常对比增强.1例DWI显示双侧顶、枕叶及额叶皮层内弥散受限呈高信号,ADC图显示邻近的皮层下白质呈高信号.4例CT显示双侧顶、枕叶及额叶对称性斑片状低密度影,3例CT未见异常.经对症处理后复查示所有病灶几乎完全吸收消失.结论PRES的影像学表现具有特征性.MRI应作为诊断本病的首选手段.

Imaging diagnosis of posterior reversible encephalopathy syndrome

Objective To investigate the imaging findings of posterior reversible encephalopathy syndrome (PRES). Methods The clinical and imaging data of 12 patients were analyzed retrospectively: 9 cases diagnosed as pre-eclampsia/eclampsia, 2 as hypertensive encephalopathy (HE), 1 as neurotoxicity induced by cyclosporine A (CSA). 12 cases were examined by MRI: 7 of them with Gd-DTPA contrast enhancement study, 4 with three dimensional time of flight magnetic resonance angiography (3D-TOF MRA) and 1 with diffusion-weighted imaging (DWI). Plain CT scan was performed in 7 patients and digital subtraction angiography (DSA) in 2 patients. Results MRI showed bilaterally symmetrical distributions of lesions, mainly located in the parieto-occipital lobes with iso-intensity or slightly low-intensity on T1WI and increased signal intensity on T2WI. FLAIR showed hyper-intensity in cortex and subcortical white matter, more clearly than T1WI and T2WI did. No apparently abnormal contrast enhancement was found after intravenous injection of Gd-DTPA. The cortex of bilateral parietal, occipital and frontal lobes in 1 case showed increased signal intensity on DWI, so was the proximal subcortical white matter on ADC map. CT studies of 4 cases demonstrated symmetric plaque-like low-attenuated lesions in bilateral parietal, occipital and frontal lobes. CT findings of other 3 cases were normal. CT or MRI for follow-up showed complete or nearly complete absorption of lesions after adequate clinical treatments. Conclusion The imaging findings of PRES are typical, so MRI should be the first choice in its diagnosis.