CT assessment of cerebral perfusion: Experimental validation and initial clinical experience

PURPOSE: To validate a dynamic single-section computed tomographic (CT) met hod to measure cerebral blood volume (CBV) and cerebral blood flow (CBF) by using a noncarotid artery as the input and to demonstrate the feasibility of this method in a pilot series of patients. MATERIALS AND METHODS: Twelve dynamic contrast material-enhanced CT studies were performed in beagles. CBV, CBF, and mean transit time (MTT) values we re calculated by using an internal carotid artery (ICA) and a noncarotid ar tery as the input artery to the brain. Patient studies with use of the radi al artery as the input were performed (a) repetitively in two patients afte r subarachnoid hemorrhage, (b) in a patient with a symptomatic ICA occlusio n before and after the intravenous injection of 1 g of acetazolamide, and ( c) in a patient with a malignant brain tumor. RESULTS: Linear regression analyses revealed highly significant correlation s (P <.001) between CBV (r, 0.98; slope, 0.96), CBF (r, 0.89; slope, 0.87), and MTT (r, 0.80; slope, 0.76) values calculated with the ICA and the nonc arotid inputs. The CT-derived patient data correlated well with ancillary c linical and neuroradiologic findings. CONCLUSION: Dynamic single-section CT scanning to measure CBV and CBF on th e basis of a noncarotid input is a highly accessible and cost-effective blo od flow measurement technique.