Familial intracranial dural arteriovenous fistulas

BACKGROUND AND IMPORTANCE: Intracranial dural arteriovenous fistulas (DAVFs) are acquired abnormal communications between dural arteries and veins. Risk factors for development include sinus thrombosis and hypercoagulability, such as occurs in heritable thrombophilias. While there have been reports of other types of vascular anomalies (such as cavernous and arteriovenous malformations) occurring in families, to our knowledge there have been no reports of familial intracranial DAVFs. We describe the first 2 cases of intracranial DAVFs occurring in first-degree relatives. CLINICAL PRESENTATION: A 66-year-old woman presented with an 18-month history of bilateral pulsatile tinnitus. Neurological examination was significant for a prominent pulsatile bruit over the left mastoid region. Laboratory studies demonstrated heterozygosity for Prothrombin G20210A mutation. Imaging disclosed a large left Type I Borden DAVF involving the distal transverse-sigmoid sinus junction. She underwent uncomplicated stereotactic radiosurgery to the fistula that led to complete resolution of her tinnitus and the fistula. A 73-year-old woman, the sister of the previous patient, presented with a 24-month history of pulsatile tinnitus affecting the left ear. Laboratory studies demonstrated heterozygosity for the Prothrombin G20210A mutation. Imaging revealed a left Type I Borden DAVF involving the left transverse and sigmoid sinuses. The patient's symptoms resolved spontaneously without treatment. Repeat imaging revealed interval involution of the fistula. CONCLUSION: We describe 2 sisters who were heterozygous for Prothrombin G20210A mutation and found to have DAVFs. Clinicians should be aware of the potential for these fistulas to congregate in first-degree relatives via heritable thrombophilias such as the Prothrombin G20210A mutation.