Isolated subdural hematoma secondary to Dural arteriovenous fistula: a case report and literature review

Background: Dural arteriovenous fistula (DAVF) is an uncommon subtype among the intracranial arteriovenous malformations, which is characterized by pathological anastomoses between meningeal arteries and dural venous sinuses, meningeal veins, or cortical veins. While intracerebral hemorrhage accounts for most of the hemorrhagic cases in patients with DAVF, isolated subdural hematoma (SDH) is rarely reported. Case presentation: A 45-year-old man was admitted for a progressively worsening headache over 2 weeks. Head computed tomography on admission revealed an isodense chronic SDH (CSDH) on the left hemisphere with mild midline shift. Further angiography of the external carotid artery revealed a DAVF at the transverse sinus. The DAVF was embolized via the middle meningeal artery. His CSDH gradually resolved without surgical intervention. In order to further elucidate this rare entity, a review of relevant literature was also conducted. Conclusions: Isolated SDH is a rare complication of DAVF. In this report, we presented a rare case of CSDH secondary to an intracranial DAVF. According to this case report and our literature review, the so-called benign type of DAVF without cortical venous drainage does not always warrant a benign process and might be complicated with SDH. Careful preoperative investigation is needed for relative young patients presenting with idiopathic or atypical SDH.