1病例介绍例1，男性，29岁。因持续剧烈头痛49天人院。无高血压病史及慢性头痛病史。外院腰穿检查诊断为蛛网膜下胜出血，经止血、降颅内压治疗头痛消失，住院1个月出院。人院前10天再次出现头痛，呕吐。脑CT检查：脑实质内可见弥漫性采粒状低密度影，边缘模糊，侧脑室变小，外 A case introduction example 1, male, 29 years old. 49 days due to sustained severe headache hospital. No history of hypertension and history of chronic headache. Outside the hospital lumbar puncture diagnosis of subarachnoid hemorrhage, hemostasis, decreased intracranial pressure headache disappeared, hospitalized 1 month discharged. 10 days before the hospital again headache, vomiting. Brain CT examination: visible intraparenchymal granular granular low density, fuzzy edge, lateral ventricle smaller, outside