Utility of the turn-back supporting technique using a steerable intermediate catheter: illustrative case.

Background: Selective shunt occlusion (SSO) for intracranial dural arteriovenous fistulas (DAVFs) is a safe and effective method that directly intercepts the shunted pouch from the affected sinus with minimal materials. However, it can be challenging to obliterate the shunted pouch if the microcatheter is not supported adequately.

Observations: A 68-year-old woman presented with tinnitus and was diagnosed with multiple shunted DAVFs in the right transverse-sigmoid sinus (TSS) and the superior sagittal sinus (SSS). Although the entire sinus packing of the right TSS was performed, a follow-up angiography 7 months later revealed significant cerebral venous reflux due to occlusion of the left TSS and an increasing residual shunt flow in the venous pouch at the confluence of the SSS. A guiding catheter was introduced into the isolated sinus transvenously. Then, a steerable intermediate catheter (SIC) was manually steered into a hairpin shape and hooked on near the pouch prior to navigating a microcatheter into the fistula point. Finally, the fistula pouch was completely obliterated using only two coils under the adequate support of the turned-back intermediate catheter.

Lessons: The turn-back supporting technique using an SIC was useful in achieving SSO for DAVFs, providing both adequate support and guidance for the coaxial microcatheter. https://thejns.org/doi/10.3171/CASE24467.