Transcranial Transvenous Embolization with Onyx through a Steerable Catheter for a Dural Arteriovenous Fistula of the Isolated Superior Sagittal Sinus: A Technical Case Report

We report a rare case of an isolated superior sagittal sinus dural arteriovenous fistula successfully treated by transcranial direct puncture transvenous Onyx embolization using a steerable microcatheter. With reduced arterial inflow and sinus balloon protection, Onyx injection through the steerable catheter achieved complete occlusion of the shunted pouch without complications. The patient showed marked improvement in cortical venous dilatation and cerebral edema. This case highlights the feasibility and safety of combining transarterial flow reduction, sinus balloon protection, and steerable microcatheter navigation for the curative embolization of isolated sinus dural arteriovenous fistulas.