脑后部可逆性脑病综合征的影像学及临床表现

Imaging and clinical manifestations of posterior reversible encephalopathy syndrome

目的探讨脑后部可逆性脑病综合征的影像学及临床表现。方法回顾分析6例脑后部可逆性脑病综合征患者的影像学表现及临床资料。结果6例患者CT示病灶呈低密度，边界不清。1例患者MRI显示双侧顶枕叶多发异常信号，在T1WI病灶呈等或略低信号，T2WI及FLAIR呈高信号。随访CT显示所有患者病灶范围、数目逐渐变小、减少，甚至消失。结论脑后部可逆性脑病综合征好发于顶枕叶脑白质，也可见于基底节、额颢叶。顶枕叶呈双侧对称性，影像学表现具有特征性，临床上均有血压突然升高。一般患者经适当治疗后，影像学表现恢复正常，临床症状消失。

Objective To evaluate the value of CT and MRI in the diagnosis of posterior reversible eneephalopathy syndrome（PRES）. Methods Eight women with PRES（6 pregnant women, 1 case after chemotherapy, and 1 patient with hypertension） were enrolled in our study. All of them had MR imaging（ T1 WI, T2WI, FLAIR, DWI）, and five cases underwent post -contrast T1 WI and three dimensional contrastenhanced MR angiography（ 3D CEMRA）, Two cases also had CT scan. Results MRV in all 8 patients showed no evidence of stenosis, dilation, or thrombosis in cranial veins and sinuses. MRI demonstrated multiple lesions located in bilateral parieto -occipital lobes（ 8 cases）, bilateral basal ganglia（ 2 cases） , and andbilateral frontal lobes（4 cases）. The lesions were prominent within white matter, some of them involvedgray matter（3 cases）. Lesions appeared as hyperintense signals on FLAIR and T2 - weighted images, isointense or mildly bypointense sign also on T1 - weighted images, normal or decreased intensity on DWI, andisointensity or hyperintensity on apparent diffusion coef- ficient（ADC） maps. Post -contrast T1WI showed mildreversible enhan cement and 3D CEMr. Displayed numerous reversible ＂grape - like＂ enhan cements interminal arterial branches along the middle cerebral artery （ MCA ）, anterior cerebral artery （ACA） andposterior cerebral artery （PCA）. Follow up scan showed decreased abnormal signals. Conclusion Lesionsof PRES are usually located in parietooc cipital lobes, especially in white matter, but they can also be seen in frontal lobes and basal ganglia bilaterally. Post -contrast T, WI and 3D enhanced MRA can provide useful information in the manifestation of reversible enhancement. MRI has advantages to display lesion in PRES.