Dural arteriovenous fistula of the hypoglossal canal treated with endovascular embolization using 3D Slicer-based preoperative planning: Case report

Hypoglossal canal dural arteriovenous fistulas (HC-dAVFs) are rare skull base vascular lesions with complex venous drainage. We report a case of a 52-year-old man who presented with 6 months of left-sided pulsatile tinnitus, sleep disturbance, and anxiety. Magnetic resonance angiography demonstrated venous engorgement near the left hypoglossal canal, and transfemoral cerebral angiography revealed early venous shunting involving the anterior condylar confluence, internal jugular vein, vertebral venous plexus, and cavernous sinus. Conventional workstation-based three-dimensional (3D) reconstruction was limited by poor differentiation of arterial and venous structures, particularly on lateral views. To better delineate the fistulous anatomy, 3D Slicer was used to independently segment arterial and venous phases from DICOM source images and generate a color-coded fused model. This reconstruction clarified the spatial relationship among the feeding arteries, draining veins, and fistulous convergence point, facilitating microcatheter trajectory planning and accurate transvenous access. Transvenous coil embolization via the right femoral vein achieved complete obliteration of the fistula. The patient's pulsatile tinnitus resolved immediately, and no postoperative neurological deficits were observed, including preserved cranial nerve IX through XII function. Follow-up at 1 month and 1 year confirmed sustained complete remission without recurrence. This case highlights the value of 3D Slicer-based preoperative reconstruction for precise angioarchitectural analysis and procedural planning in HCdAVFs when conventional 3D workstation imaging is limited by vessel overlap.