A case of subdural hemorrhage due to ruptured cerebral aneurysm presenting with atypical imaging features.

Acute subdural hemorrhage caused by ruptured cerebral aneurysms is rare. Herein, we report an atypical case of subdural hemorrhage caused by ruptured anterior communicating artery aneurysm in a 49-year-old woman. Computed tomography revealed subarachnoid, intracerebral, and subdural hemorrhages. After the treatment with endovascular coiling significantly decreased the patient's subdural hemorrhage. However, the subdural hemorrhage revealed and became iso-attenuation compared with the white matter on the 11th day, and hypo-attenuation on the 19th day. On the 33rd day, this subdural hemorrhage completely resolved after discontinuation of dual antiplatelet therapy. Due to rapid changes in the radiologic features of SDH, frequent computed tomography scans at least once a week may be needed especially in patients who receive antiplatelet therapy during the vasospasm phase.