Imaging of vasospasm

: Neuroimaging is of paramount importance in the evaluation and management of cerebral vasospasm. Arteriographic demonstration of concentric arterial constriction between 4 and 12 days after subarachnoid hemorrhage is the definition of vasospasm. Assessment of angiographic vasospasm is subjective. Vasospasm must be differentiated from hypoplasia, atherosclerosis and other non specific arteriographic conditions. The development of vasospasm is directly correlated with the presence of thick blood clots in the basal subarachnoid cisterns which can be detected by an early computed tomography scan. MR imaging and evaluation of cerebral blood flow are useful in the early identification of cerebral ischemia.