Fig. 3
From: Intracranial vessel wall MRI: a review of current indications and future applications
a 3D axial T1-weighted post-contrast image showing the “tram track” appearance (white arrow) of a peripheral MCA branch with concentric enhancement from presumed cerebral vasculitis due to inflammatory amyloid angiopathy with adjacent leptomeningeal enhancement from recen superficial siderosis. b Higher magnification of the same patient showing the tram track appearance of concentric enhancement. c 3D axial T1-weighted post-contrast image in a second patient with bacterial meningitis and associated vasculitis, showing the concentric vessel wall enhancement in both terminal internal carotid artery segments (white arrows), which extends along the left middle cerebral artery vessel. d Lateral digital subtraction angiography showing a basilar artery dissection and near occlusion (minimal distal flow was seen on delayed imaging-not shown) (white arrow). e Axial diffusion-weighted image showing a pontine ischemic stroke (white arrow) which resulted from the dissection. f 3D axial T1-weighted image, proximal to occlusion, showing eccentric wall thickening with T1 hyperintense signal (short white arrow) representing arterial dissection, with the remaining patent lumen (thick arrow)