Intracranial Vessel Wall Plaque and Lumen Evaluation

The intracranial vessel wall images were evaluated by two independent neuroradiologists (LN, FZ, with 7 and 4 years of experience in neurovascular imaging, respectively), who were blinded to the WMH information, using a Philips MR workstation (Extended Workstation, EWS) (Qiao et al., 2014). The range of intracranial atherosclerosis we evaluated included the intracranial portion of the internal carotid artery (ICA) to the second segment of the anterior, middle, and posterior cerebral arteries. The degree of plaque enhancement was graded as follows: 0 = no enhancement; 1 = mild enhancement; and 2 = obvious enhancement (Qiao et al., 2014). The presence or absence of contrast-enhanced lesions in the aforementioned arteries was determined. If multiple arterial segments showed plaque enhancement, the segment with the most severe stenosis was considered the location of the lesion. The ICAS stenosis was graded as follows: 1 = mild (<50%); 2 = moderate (50–69%); 3/4 = severe stenosis/occlusion (70–100%), based on the North American Symptomatic Carotid Endarterectomy Trial Collaborators (NASCET) criteria.