PTPRC and vasculitis: MRI brain: Left parietal-occipital DWI hyperintense and ADC hypointense lesion; MRI brain after 8 weeks: multiple bilateral ischemic infarcts with mild hemorrhagic conversion; MRA: mild stenosis of bilateral ICA, MCA, ACA, and left VA; MRI brain after 13 weeks: new multistage bilateral infarcts with unchanged MRA; conventional angiogram: multiple focal segmental narrowing suggesting vasculitis; brain biopsy: discohesive cells with high nucleus to cytoplasm ration in the vascular spaces which were immunoreactive to CD45 and CD20 antibodies suggesting IVL