Primary angiitis of the central nervous system.

Despite the multiple areas of progress that have been made in our understanding of primary angiitis of the central nervous system (PACNS ), many challenges exist when facing this diagnosis. This review will address the clinical presentation, diagnosis and differential diagnosis of PACNS, with emphasis on the recognized advancement in the field. Appreciation of different mimics especially the recognition of reversible cerebral vasoconstriction syndromes (RCVS) as a major mimic will be addressed. Finally, approach to treatment will be summarized.