Abstract: Objective To investigate the clinical and radiological features and prognosis of perimesencephalic nonaneurysmal subarachnoid hemorrhage (PNSH).Methods Total 34 cases whose subarachnoid hemorrhage lesions were found only within perimesencephalic cisterns were retrospectively investigated, including the clinical data, radiological features, treatments and prognosis.Results All the patients were conscious, whose Hunt-Hess scale were Grade I to II and they were all cured, without serious cerebral vasospasms, hydrocephalus, or rebleeding.Conclusion It is important for correct analysis of PNSH to improve correct diagnosis and treatments.

Key words: Subarachnoid hemorrhage; Mesencephalon; Clinical features

摘要： 目的 分析中脑周围非动脉瘤性蛛网膜下腔出血（PNSH）的临床及影像学特点及预后。方法 回顾性分析34例出血部位仅限于中脑周围脑池的PNSH的临床及影像学资料、治疗与预后。结果 34例PNSH患者无意识障碍， Hunt-Hess分级均为Ⅰ～Ⅱ级,无明显的脑血管痉挛、脑积水与再出血，预后较好。结论 正确认识中脑周围非动脉瘤性蛛网膜下腔出血可提高蛛网膜下腔出血的临床诊治水平。

关键词: 蛛网膜下腔出血; 中脑; 临床特点