Early experience in high-resolution MRI for large vessel occlusions

Background Large vessel occlusions are an important cause of ischemic stroke. Imaging goals center on identifying the site of occlusion, the size of the ischemic core and the size of the ischemic penumbra. The etiology of the occlusion is typically inferred by history and demographics, or subacutely during investigation for shunt, hypercoagulable state or other causes. Current generation vascular imaging is based primarily on lumenography. Contours of the vessel lumen on lumenography may suggest the presence. of atherosclerosis, dissection or thrombus. High-resolution MRI (HRMRI) techniques can characterize wall morphology in the presence of an occlusion, which may affect clinical care by better definition of intra-occlusion wall characteristics as well as downstream vasculature normally confounded by the lack of antegrade flow. Methods The HRMRI databases of Cleveland Clinic and Beijing Tiantan Hospital were reviewed to identify patients with large vessel occlusions on lumenography, performed with a diagnostic quality HRMRI. Clinical data were reviewed for each patient and images were analyzed by experienced neuroradiologists at both institutions. Where possible, conventional angiography/lumenography was reviewed for comparison. Results Nine patients with large vessel cerebral artery occlusions were identified in whom HRMRI characteristics were reviewed and categorized. Images were correlated with demographics, risk factors and the working diagnosis of each case. Conclusions HRMRI of vascular occlusions can identify wall characteristics and characterize the course and caliber of the vasculature distal to the occluded segment. This information may be useful in determining preferred approaches for endovascular revascularization.