Perfusion CT to quantify the cerebral vasospasm following subarachnoid hemorrhage

International audience; BACKGROUND AND PURPOSE: After subarachnoid hemorrhage (SAH), vasospasm is frequent and increases the risk of stroke and poor clinical outcome. The purpose of this study was to identify the best perfusion parameters in perfusion-CT (PCT) able to predict vasospasm diagnosed by angiography after SAH. METHODS: Seventy-six patients with SAH were investigated by PCT and cerebral angiography. Using regions of interest (ROI) on parametric maps of mean transit time (MTT), time to peak (TTP), cerebral blood volume (CBV) and cerebral blood flow (CBF), PCT data were compared to an arteriographic score in two categories (severe vasospasm: ≥ 50% and non-severe vasospasm