蛛网膜下腔出血的CT诊断及其漏误诊原因分析

目的探讨蛛网膜下腔出血的CT诊断并分析其误诊、漏诊的常见原因。方法对100例经CT复查证实的蛛网膜下腔出血CT资料进行回顾性分析。结果100例中因出血部位及出血量不同，CT表现为分布于脑沟、裂、池内的线状、带状、片状或铸型高密度影。纵裂池及小脑幕出血灶边缘一般较模糊。出血部位以侧裂池和脚间窝最多，分别为46例及56例，2例纵裂池出血首次误诊为硬膜下血肿；1例四叠体池出血因出血量少首次CT检查为阴性，通过适时CT复查得以确诊。结论CT对蛛网膜下腔出血的诊断价值较高，可避免漏诊及误诊，并对其临床治疗具有重要把寻意义。

CT diagnosis of subarachnoid hemorrhage and its misdiagnostic cause analysis

Objective To study the CT findings of subarachnoid hemorrtmge（SAH） and to analyze its misdiagnostie causes.Methods A hundred patients with SAH confirmed by CT reexaminations underwent conventional CT scans of the brain and then whose CT data were analyzed retrnspectively.Results Due to different hemorrhagic locations and amounts, the SAH lesions appeared as linear,strip,patchy or mould-form hyperdense shadows in cerebral groove,fissure and cistern on CT images.The hemorrhagic lessions in longitudinal fissure cistern and eerebcral tentoria frequently appeared as hazy margin.The locations of SAH were mainly in sylvian fissure cistern （n=46） and interpeduncular cistern （n =56）.Two patients with longitudinal fissure cistern hemorrhage were initially misdiagnosed as subdural hematomas on CT images.One patient with quadrigeminal cistern hemorrhage was initially negative on CT image due to hemorrhagic amount too little,subsequently it was demonstrated by CT reexamination.Conclusion CT plays important role in the diagnosis and differential diagnosis of SAH and it has guiding significance for clinical treatment.