History of elective carotid stenting on 11/2/15 for an incidental 2.3 cm right-sided carotid aneurysm. The stent was deployed in the appropriate location, but the superior portion of the stent retracted into the aneurysmal sac and was unable to be re-wired. The patient complained of a headache and nausea the following morning which prompted a CT head which demonstrated a new region of hypodensity in the lateral right precentral gyrus. There are multiple foci of restricted diffusion and corresponding T2 hyperintensity involving the grey-white matter junctions in the right cerebral hemisphere. The largest area is in the right frontal opercular region and measures up to approximately 20 mm. There is a partially-imaged stented pseudoaneurysm that measures up to 25 mm in width. In particular, the superior end of the stent lies within the pseudoaneurysm sac, rather than within the parent vessel, which appears to be compressed by the pseudoaneurysm. There is no evidence of intracranial hemorrhage or mass. There is no abnormal intracranial enhancement. The ventricles and basal cisterns are normal in size and configuration. There is no midline shift or herniation. The major cerebral flow voids are grossly intact. The orbits, skull, paranasal sinuses, and scalp soft tissues are grossly unremarkable. There is high T2 signal and enhancement surrounding the root of a left mesiodens.
1. Multiple acute to early subacute right cerebral hemisphere infarcts essentially scattered throughout the middle cerebral artery territory, which may represent an embolic stroke related to the recent endovascular stenting of the right cervical internal carotid artery pseudoaneurysm. 2. The cervical right internal carotid pseudoaneurysm has not decreased in size and the superior end of the stent lies within the pseudoaneurysm sac, rather than within the parent vessel. Dedicated vascular imaging may be useful for further evaluation.2. Possible inflammatory changes associated with a left mesiodens.