Fig. 1

Baseline and follow-up brain MRI and CT angiography of the aortic arch. Figure Legend. Axial brain DWI showing minor foci of restricted diffusion in the parietal cortical territory of the left MCA (a-b). There is total matching of the lesion size between DWI and FLAIR images (c). Repeat axial brain DWI showing a recurrent infarction in the posterior left MCA territory (d). Oblique sagittal reformatted CT angiography showing a broad-based thrombus (asterisk) situated at the inferior wall of the aortic arch, facing the origin of the great vessels. Notice the origin of the left common carotid artery (curved arrow) from the brachiocephalic trunk (arrow), so-called “bovine arch”, and the origin of the left subclavian artery (arrowhead) (e). Axial CT angiography showing the floating intraluminal thrombus as a flame-like filling defect attached to the wall of the aortic arch (f). Follow-up reformatted axial (g) and sagittal (h) CT angiography confirming complete dissolution of the thrombus after anticoagulation. Notice the mild subjacent atheroma (arrowhead) that nested the thrombus. Follow-up oblique axial CT angiography demonstrating an outpouching of the contrast medium (arrowhead), representing a shallow ulceration in the subjacent atheroma (i)