Making Microguidewire Loop Facilitates Navigation Through Tortuous or Abruptly Angulated Head and Neck Veins to Access Cavernous Sinus Dural Arteriovenous Fistulas.

Background: The transvenous approach via the inferior petrosal sinus (IPS) is the most commonly used route to access cavernous sinus dural arteriovenous fistulas (CSDAVF). The facial (FV) or superficial temporal vein (STV) are alternatives in cases with IPS occlusion. However, navigation through the ophthalmic vein via FV or STV is difficult because of its specific anatomical features, such as abrupt angulations and tortuous course. Herein, we introduce a microwire looping method to overcome these obstacles, thus enabling access to cavernous sinus.

Methods: We initially tried to navigate a microcatheter through the vein using a conventionally shaped microguidewire tip. If the traditional method failed, we made a single- or double-looped microguidewire. After anchoring the microguidewire, we pushed the microcatheter to add microcatheter tension and steered the microguidewire. Then, looping was formed and the looped microguidewire tip was easily passed through the abruptly angulated or tortuous vein.

Results: This looping technique was applied in 7 CSDAVFs (4 were through FV and 3 were through STV) that were unable to pass through IPS. In all cases, a total of 10 microcatheters (4 with single microcatheter and 3 with double microcatheters) successfully approached CSDAVF, achieving effective transvenous coil embolization. The clinical and radiologic outcomes were excellent in all patients. There was 1 postprocedural cranial nerve palsy without any morbidity or mortality.

Conclusions: Making a microguidewire loop to pass through abruptly angulated or tortuous head and neck veins might be an effective and safe alternative for when catheterization is not feasible by the traditional method.