Vessel Wall Imaging for Diagnosis and Monitoring of Central Nervous System (CNS) Vasculitis

This study will evaluate patients with suspected primary angiitis of the central nervous system (PACNS), recruited during initial work-up by our multi-disciplinary team. Given the low incidence of CNS vasculitis and the fact that some patients are routed to a quaternary care center after initial work-up and diagnosis, evaluation of both groups will be useful to maximize the number of participants evaluated and to provide a representative sample of patients typically treated. During the study, participants will ultimately be deemed to have; 1. A specific clinical and pathologic subtype of PACNS, 2. PACNS not otherwise specified (NOS) without pathologic or clinical proof of a specific subtype, or 3. An alternative diagnosis other than PACNS. Patients will undergo a standardized imaging and clinical examination at presentation and at pre-defined follow-up periods. Imaging examinations will include an MRI of the head, standard magnetic resonance angiogram (MRA) of the head, and intracranial vessel wall imaging without and with IV gadolinium. Patients will receive up to 4 imaging examinations at predefined intervals as part of this study. MRI/MRA/Vessel wall features will be evaluated by 2 neuroradiologists. Imaging findings will be correlated to clinical and any available laboratory or pathologic data. The target accrual is 10 patients for this pilot study.