C35 Traumatic dissecting pathology of posterior cerebral artery – report of two cases – aneurysm and pial arteriovenous fistula

<h3>Introduction</h3> Trauma is one of the recognized caused for dissection and intracranial dissections can present depending upon the pathology either as stenotic lesions, aneurysms or fistulas. Traumatic dissecting PCA aneurysm has been reported in only 2 case reports previously and post traumatic pial AVF in PCA has not been reported. <h3>Case Description</h3> We present two cases of 17-year and 10-year old male presenting with subarachnoid hemorrhage and history of road traffic accident. One patient had dissecting aneurysm of posterior cerebral artery (PCA) on CT angiography and DSA. The other patient had partially thrombosed aneurysm on CTA; on DSA, there was fistulous communication between PCA – P1/P2 segment and pontomesencephalic vein – pial arteriovenous fistula (PAVF). Both the patients underwent endovascular treatment – stent assisted coiling for aneurysm and coiling with parent vessel occlusion for PAVF. There were no procedural complications. Follow up angiography showed no residual aneurysm or fistula. <h3>Conclusions</h3> Parent vessel occlusion is preferred treatment for dissecting aneurysms due to higher chances of recurrence with selective coiling of aneurysm. Stent assisted coiling can be done in cases of poor distal collaterals. Endovascular interruption of the fistula with obliteration of feeder vessels is usually sufficient for treatment of pial AVF, and complete excision is not needed due to absence of nidus. Coil embolisation is better for high flow fistulas as opposed to liquid embolic agents. <h3>Conflict of Interest</h3> No