1Waqar Haider Gaba, 1Manzoor Ahmed, 2Syed Irteza Hussain
1Sheikh Khalifa Medical City, Abu Dhabi, United Arab Emirates; 2Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates
Carotid cavernous fistula (CCF) is an abnormal communication between the carotid artery and the cavernous sinus by virtue of unique traversal of an artery through a venous lake. About 70% of them are of direct type (Type A), mostly post-traumatic. The rest are of in-direct type, further sub-divided into Type B, C & D based on the arteriovenous connection of ICA & ECA branches. Acute post-traumatic presentation on initial imaging is unusual as demonstrated in our case. More unusual and interesting is active leakage via skull base fracture into oro-digestive tracts.
A 35-years-old gentleman presented with severe head injury after a fall from 12 meter height. He was intubated to maintain his airway. CT face showed multiple facial and skull base fractures with contrast extravasation at the right sphenoid region, contrast pooling pouring down the pharynx & oesophagus with dilated blood-filled oesophagus causing “Pseudo-vessel appearance”. CT chest showed signs of contrast aspiration. CT angiography confirmed carotid-cavernous fistula. Patient was transferred to nearby facility for embolization. The fistula was successfully occluded through coil occlusion of ipsilateral ICA after balloon test occlusion. Follow up CT two days later did not show any infarcts. Patient developed progressive ARDS, shock and died 4 days later.
CCF is an uncommon vascular entity. Trauma to the central skull base is the most common cause resulting in direct arterial communication with surrounding venous blood compartment of the cavernous sinus (Barrow’s Type A). The pathogenesis of presentation is typically rooted in venous hypertension, usually limited to ipsilateral orbit. Single phase CTA can easily yield a diagnosis in direct fistulas due to high flow fistulous connection. IV contrast administered for CTA in our case and appearing in the pharynx, oesophagus & airways indicated breach of the cavernous sinuses dural wall and further complicated by associated CCF. Trans-arterial embolization and occlusion of the injured vessel after a balloon test occlusion is commonly employed compared to trans-venous occlusion of the cavernous sinus in such post traumatic fistulas.