Semi-quantitative assessment of flow dynamics during indocyanine green video-angiography in the treatment of intracranial dural arteriovenous fistulas: how I do it.

BACKGROUND: Indocyanine green video-angiography (IG-VA) is applied for intraoperative localisation and verification of surgical disconnection of intracranial dural arteriovenous fistulas (iDAVFs). METHOD: We describe the technique of semiquantitative flow analysis using Flow800 software that implements conventional IG-VA. Our method relies on simple comparison of the fluorescence curves of the exposed vessels, allowing precise localisation of the DAVF draining vein and verification of its surgical disconnection. CONCLUSIONS: Semi-quantitative flow analysis with Flow800 software during IG-VA is a reproducible technique that may overcome the limitations of conventional IG-VA in the surgical treatment of DAVFs