Bilateral carotid-cavernous fistulas following trauma: A rare case of diagnostic and management challenges

A 23-year-old male presented with a 6-month history of left eyelid swelling and a 2-week history of headaches following a road traffic accident. Examination revealed left eye proptosis (23 mm vs. 19 mm on the right, normal 16 mm), limited abduction of the right eye, incomplete closure of the right upper eyelid, and right facial nerve weakness. No relative afferent pupillary defect (RAPD) was noted. Musculoskeletal ultrasound of the left eyelid identified an elongated subcutaneous cystic lesion with intense vascularity, indicative of a vascular lesion. CT of the facial bones with 3D reconstruction revealed bilateral proptosis, dilated superior ophthalmic veins, and enlarged cavernous sinuses, consistent with bilateral carotid-cavernous fistulas (CCFs). Otomastoiditis with facial nerve canal dehiscence was also noted, suggesting facial nerve involvement. MRI brain and orbit with gadolinium contrast demonstrated multiple dilated tortuous vascular structures communicating with the cavernous sinuses, dilated bilateral superior ophthalmic veins (left > right), and left eye proptosis, consistent with high-flow fistulas. High-flow characteristics were supported by early arterial filling of the cavernous sinuses, retrograde venous drainage, and superior ophthalmic vein dilation on MR angiogram. Bilateral CCFs are rare, typically resulting from trauma, and often present with proptosis, cranial nerve deficits, and orbital symptoms. Fundus examination revealed engorged retinal veins and mild optic disc swelling in the left eye, consistent with venous stasis. Endovascular surgery is the gold standard for treatment; however, this patient was managed symptomatically with analgesics due to financial constraints. This case demonstrates the importance of imaging in diagnosis and highlights the challenges of managing CCFs in resource-limited settings.