可逆性后部脑病综合征的影像学表现及诊断

Imaging Findings and Diagnosis of Posterior Reversible Encephalopathy Syndrome

目的探讨可逆性后部脑病综合征(PRES)的影像学特点及诊断价值。资料与方法回顾性分析15例PRES患者的临床和影像学资料,其中子痫或先兆子痫7例;原发性高血压1例;肾性高血压2例;肾移植及骨髓干细胞移植后3例,其中2例移植后使用环孢素A治疗;系统性红斑狼疮1例;行全脑血管造影使用非离子型对比剂诱发1例。结果PRES的CT表现主要以顶枕叶白质呈低密度改变为特征,增强后无强化。顶叶、枕叶及额叶同时见低密度7例;顶叶及枕叶同时见低密度5例,其中2例有出血;顶叶、枕叶、额叶及基底节区或小脑白质同时见低密度2例;单纯枕叶见低密度1例。MRI对于诊断病变有无、病灶范围及皮层受累比CT更敏感。顶叶、枕叶、额叶及基底节区或小脑白质广泛低密度者疗效不佳;顶叶、枕叶及额叶低密度者与单纯枕叶低密度者全部恢复良好,呈可逆性改变。经过积极治疗,先兆子痫与子痫、原发性高血压、药物毒性所致PRES恢复良好。结论结合PRES的影像学特点,了解其临床表现、病因及用药情况,综合分析,有利于早期做出诊断,提高治愈率。

Objective To investigate the imaging features and diagnosis of posterior reversible encephalopathy syndrome （PRES）. Materials and Methods The clinical and imaging data of 15 patients with PRES were retrospectively analyzed,including 7 patients with eclampsia or preeclampsia, the others with primary hypertension （ 1 patient） , renal hypertension （2 patients）, renal transplantation or bone marrow stem cells transplantation （3 patients）, systemic lupus erythematosus（1 patient）, cerebral angiography by use non-ionic contrast agent（1 patient）. Results The imaging characteristics of PRES on CT were hypodensity in white matter of parietal lobe and occipital lobe without enhancement. MRI was more sensitive than CT to detect lesions. The findings of CT showed that 7 cases had hypodensity in parietal, occipital and frontal lobe, 5 cases in parietal and occipital lobe including 2 cases with bleeding in the lesions. Patients with widespread hypodensity of the parietal, occipital, frontal lobes, basal ganglia or cerebellum had poor prognosis （ 2 patients）, and reversible changes usually occurred in parietal lobe, occipital lobe, frontal lobe and simple occipital lobe. Patients with preeclampsia and postpartum eclampsia, primary hypertension, renal insufficiency and drug toxicity showed favorable prognosis. Conclusion The early diagnosis of PRES depends on imaging characteristics, clinical features, etiology and medication condition.