Abstract Number ‐ 70: Combined Trans‐arterial Flow Diversion and Trans‐venous Embolization Management of High‐Flow Traumatic Cavernous‐Carotid Fistula (CCF)
Authors: Eldokmak Mohamed , Eldokmak Mohamed , Mulatu Yohannes , Ramaswamy Srinath , Buciuc Razvan , Houten John K. , Wang Qingliang T. 
Published: April 2023

Introduction
Carotid‐Cavernous fistulas (CCF) are abnormal vascular shunts between the internal carotid artery (ICA) and the cavernous sinus. Most commonly due to trauma (75%), CCF occurs in 4%(1) of skull‐base fracture patients. Visual impairment, diplopia, and headache are typical presenting symptoms (88%). Proptosis, chemosis, ophthalmoparesis, and orbital bruits are notable exam findings. Cerebral angiography is the gold standard for diagnosis, showing cavernous sinus enlargement and ophthalmic vein or leptomeningeal vessel dilatation. CCF is typically treated endovascularly andballoon embolization has achieved cure rates of 88–99%(2). Successful obliteration using stents, however, has been reported(3, 4). While both trans‐arterial and the trans‐venous approach embolization are feasible depending on local vascular anatomy and accessibility of fistula points, the combination of trans‐arterial and trans‐venous approach is rarely employed.We present a case of traumatic, high‐flow CCF treated with combined trans‐arterial and trans‐venous coiling embolization and telescoped flow‐diverting stents.

Methods
A case report of successful treatment of traumatic high‐flow CCF with a combined trans‐arterial and trans‐venous coiling embolization with telescoped flow‐diverting stents.

Results
A 26‐year‐old woman presented with right eye proptosis, periorbital ecchymosis, and chemosistwo weeks after severe closed head injury treated with decompressive hemicraniectomy and subdural hematoma evacuation. Examination was notable for right eye blindness without light perception and right‐sided third, fourth, and sixth cranial nerve palsies and elevated intraocular pressure. CT head showed a skull base fracture involving the right carotid canal and angiography of ICA confirmed a high‐flow multi‐channel right CCF with diminished intracranial arterial flow and engorged bilateral ophthalmic veins. After unsuccessful attempts to catheterize the fistula via arterial approach, superior‐segment coil embolization was performed using an inferior petrosal venous approach; but further embolization of the cavernous sinus was unsuccessful. Using the cavernous‐petrous segment of the right ICA, a flow‐diversion stent was placed that significantly decreased cross‐fistula blood flow, improved intracranial arterial flow, and reduced bilateral ophthalmic vein congestion. After two months, intraocular pressure normalized and right eye vision returned, though moderate exophthalmos persisted. Angiography showed decreased but persistent residual CCF flow. Another flow‐diversion stent was successfully placed via trans‐arterial approach, covering the previous pipeline stent through petrous‐to‐ophthalmic right ICA. Three‐month follow‐up angiogram showed closure of the CCF with complete restoration of right eye vision. She ultimately underwent right cranioplasty and was able to return to work.

Conclusions
A combined trans‐venous coiling embolization and trans‐arterial flow‐diversion stenting may be effectively employed in the treatment of CCF with reversal of clinical symptoms and restoration of visual loss. Larger studies are needed to explore the role of this combined approach in the management of CCF.