Background: Dural arteriovenous fistula (DAVF) has been reported as a rare cause of chronic subdural hematoma (CSDH); however, CSDH associated with a Cognard type IIa+b DAVF has not been reported. Case Description: A 56-year-old woman without traumatic history presented with headache and was diagnosed with right-sided CSDH and a transverse-sigmoid sinus DAVF. She underwent transvenous and transarterial embolization along with burr-hole drainage. Although residual shunting persisted after the first session, complete resolution was achieved after the third. Over 4 years of follow-up, there was no recurrence of CSDH or DAVF. Conclusion: This case highlights that DAVFs can cause CSDH regardless of the Cognard type, and that combined curative DAVF treatment and drainage may be effective.
Teranishi et al. (2025) studied this question.