DSA在显示微小畸形血管团方面优于CTA或MRA，能提供bAVM的血管结构特征和血流动力学信息。但DSA属于有创检查，存在一定的风险，对于首次DSA阴性的SAH患者是否复查应视具体情况而定。

A perimesencephalic distribution of nonaneurysmal subarachnoid blood on CT imaging has been described as a distinct clinical entity with a benign course and an excellent prognosis; research ...