Diagnosis of cerebral vasospasm and risk of delayed cerebral ischemia related to aneurysmal subarachnoid haemorrhage: an overview of available tools.

In the first weeks following aneurysmal subarachnoid haemorrhage, cerebrovascular alterations may impact the outcome significantly. Diagnosis of cerebral vasospasm and detection of alterations at risk of delayed cerebral ischemia are key targets to be monitored in the post-acute phase. Available tools include clinical monitoring, as well as studies that can detect possible arterial narrowing, alterations of perfusion, metabolism and neurophysiology. Each technique is able to investigate possible vascular impairment and has different advantages and limits. All available techniques have been described. Among these, the most practical have been selected and compared for their peculiar characteristics. Based on this analysis, a flowchart to monitor these patients is finally proposed.