Unmasking a Rare Venous-Predominant Arteriovenous Malformation: A Case of Recurrent Subarachnoid Hemorrhage Successfully Treated With Stereotactic Radiosurgery.

Arteriovenous malformations (AVMs) are a leading cause of intracranial hemorrhage in young adults, yet venous-predominant AVMs remain exceedingly rare and diagnostically challenging, often mimicking benign developmental venous anomalies (DVAs). We present the case of an 18-year-old male who suffered from recurrent subarachnoid hemorrhages due to a venous-predominant AVM initially misidentified as a DVA. Given the lesion's deep location and high surgical risk, stereotactic radiosurgery (SRS) was selected as the primary treatment modality. Over a 64-month follow-up, the patient demonstrated progressive obliteration of the AVM, culminating in complete resolution on conventional angiography at 55 months post-SRS. This case underscores the critical role of advanced imaging in distinguishing rare AVM subtypes, the importance of multidisciplinary decision-making, and the long-term efficacy of SRS in managing high-risk vascular lesions.