Development of a dural arteriovenous fistula subsequent to cerebral venous thrombosis by venous hypertension.

Dural arteriovenous fistulas (dAVF) refer to an aberrant connection between an artery and a vein within the dura. Although the pathogenesis of dAVF is unclear, a link to cerebral venous thrombosis (CVT) has been posited though not fully identified. The current case is the first report demonstrating dAVF formation following CVT according to dynamic changes in the intracranial pressure and venous drainage pattern. This observation provides insight into the pathophysiological association between dAVF and CVT. A 60-year-old woman presented with acute onset of a severe headache and first-onset seizure. Initial magnetic resonance imaging showed an extensive thrombosis in the cerebral venous sinuses. However, there was no evidence of any vascular malformation. Eight months later, she reported dizziness, visual obscurations and pulsatile tinnitus. Follow-up digital subtraction angiography showed multiple dAVFs. Endovascular treatments for the dAVF embolization was performed twice, resulting in the obliteration of the dAVF along with the resolution of her optic disc edema, visual obscurations and tinnitus. The degree and pattern of the venous pressure, not hypoxia-induced growth factors, are the key pathogenic mechanisms of dAVF following CVT. Oral anticoagulants and good adherence do not ensure the prevention of dAVF. Thus, careful clinical observation and follow-up examinations are recommended.