Acute spontaneous subdural hematoma secondary to ruptured arteriovenous malformation: A rare entity

INTRODUCTION: Acute spontaneous subdural hematoma (ASSDH) due to ruptured arteriovenous malformation (AVM) is exceptional. There were only four reported cases. In this paper, we present a successful multimodality treatment of the ASSDH secondary to ruptured AVM. CASE PRESENTATION: A 21-year-old healthy man with no history of trauma presented to our hospital with complaints of severe headache for 12 hours before admission. On examination, he was alert and oriented. He had no intracranial hypertension, meningismus, and neurological deficits. Computed tomography illustrated a right acute subdural hematoma 8mm in thickness with a 5mm midline shift and a right frontal intraparenchymal hemorrhage 40 × 25mm in size. Digital subtraction angiography showed a 2 × 3 cm right frontal AVM, Spetzler-Martin grade I. The feeding arteries were cortical branches of the right anterior cerebral artery, and drain veins were cortical veins. He received emergency preoperative embolization followed by hematoma evacuation and total excision of the malformation. His headache was relieved and disappeared after a week. No postoperative neurological deficits were reported. CLINICAL DISCUSSION: Elective surgical resection of AVM after 4–6 weeks was preferred in patients with no risk factors of rebleeding. Emergent surgery was only indicated for significant mass effect or acute hydrocephalus. Preoperative embolization is helpful for the presence of intra-nidal or peri-nidal aneurysm, AVM with high grades, reducing intraoperative blood loss and occlusion of deep vessels. CONCLUSION: ASSDH due to ruptured AVM is rare and easy to omit in clinical settings. Preoperative embolization and surgical excision are effective treatments.