Serial vessel wall enhancement pattern on high-resolution vessel wall magnetic resonance imaging and clinical implications in patients with central nervous system vasculitis

High-resolution vessel wall imaging (HR-VWI) often demonstrates strong and concentric vessel wall enhancement (VWE) in patients with central nervous system vasculitis (CNS-V). However, little is known about follow-up VWE characteristics and monitoring the response to treatments. The aim of this study was to investigate serial VWE patterns and its clinical practice through the management of CNS-V.We extracted 9 patients with diagnosed of CNS-V who underwent serial HR-VWI (baseline, 1st follow-up, and 2nd follow-up) from Cleveland Clinic CNS vasculopathy registry. VWE were analysed in 17 intracranial artery segments. VWE was graded on a 3-point scale (0; none, 1; mild/eccentric, and 2; strong/concentric). VWE grade for each arterial segment was summed to create a total VWE score. We investigated the relationship between serial VWE patterns and clinical course.In unique 153 intracranial arterial segments, 39 arteries (25.5%) had strong/concentric VWE on baseline HR-VWI. The positive rates of concentric VWE have decreased to 12.4% (19/153) at 1st follow-up and (10/153) 6.5% at 2nd follow-up, respectively (p<0.001). Mean total VWE scores have significantly decreased over time courses (p=0.034). Two patients had relapse at 1st follow-up image. In relapse cases, mean total VWE scores have worsened at 1st follow-up (baseline:2.0 to 1st follow-up: 6.0). After intensive immunosuppressive treatment, mean VWE scores have improved at 2nd follow-up (1st follow-up: 6.0 to 2nd follow-up: 2.0).Decreasing contrast VWE at follow-up images may indicate good response to treatment in CNS-V. By contrast, relapse patients might have temporal VWE worsening during the clinical course.