Introduction: Spontaneous acute subdural hematoma (ASDH) is rare and comprises 2.6% of all ASDH. In one recent study, only 178 spontaneous ASDH were documented. However, only 1 case was attributed to dural arteriovenous fistula (dAVF). Vascular malformations cause less than 10% of subarachnoid hemorrhage (SAH). Spontaneous ASDH and SAH occurring together are extremely rare. Literature is scarce on cases with dAVF of the occipital lobe as a cause of simultaneous spontaneous ASDH and SAH. Objective: This paper aims to present a case of a spontaneous acute subdural hematoma and subarachnoid hemorrhage caused by a dural arteriovenous fistula of the occipital lobe, along with its clinical presentation, diagnosis, and treatment. Case Summary: A 44-year-old Filipino male with no history of trauma presented with severe headache, vomiting, and decreasing sensorium – CT scan revealed acute parenchymal bleed in the left occipital lobe with subarachnoid extension and subdural hematoma in the left fronto-parieto-temporal convexity along the tentorium cerebelli and posterior interhemispheric falx. Due to the location of the lesion seen on the CT scan and the gender distribution, Arteriovenous malformation (AVM) was initially considered, thus proceeded to computed tomography angiogram (CTA) to establish the diagnosis of vascular anomaly, however, revealed dAVF instead. Four-vessel angiogram was done to assess the tributaries of the dAVF and confirmed the diagnosis. Complete obliteration of dAVF of the occipital lobe was done with Onyx Embolization in one session. Conclusion This is the first case of Borden type II, Cognard type IIa+IIb dAVF, as reported in this institution. Although extremely rare as a cause of SAH and ASDH, dAVF should be considered a differential diagnosis in patients with no identifiable common cause of the new onset of severe headache and poor neurologic status.
Subarachnoid Hemorrhage