Internal carotid artery thrombus. 36-year-old-man with COVID-19 transferred to ICU on extracorporeal membrane oxygenation, developed acute onset of quadriplegia. Axial image from a CT angiogram shows acute thrombus within the right internal carotid artery (arrow). Atherosclerotic changes were not present in the remainder of the intra- and extracranial arterial vasculature