A new technique for quantitative imaging of cerebrovascular reserve capacity using a double injection method with...

Estimation of local cerebrovascular reserve capacity is an important aspect of the management of patients with cerebrovascular occlusive disease. Regional normal values of cerebrovascular reserve capacity have not yet been established. Recently, Mori et al. (1994) introduced a method to quantitatively measure cerebral blood flow twice in 30 min after a double injection of N-isopropyl-p-[123I]iodoamphetamine using a background subtraction method. We utilized this double injection method in tandem with acetazolamide (20 mg/kg, intravenous injection) in 10 normal volunteers to produce a map of quantitative cerebrovascular reserve capacity using single photon emission computed tomography. The normal regional cerebrovascular reserve capacity was: frontal lobe, 51.0 +/- 19.8%; temporal lobe, 53.6 +/- 12.4%; parietal lobe, 69.3 +/- 31.8%; basal ganglia, 85.1 +/- 42.7%; cerebellum, 49.6 +/- 17.9% (mean +/- SD). One-way analysis of variance showed that the cerebrovascular reserve capacity did not differ significantly among structures. This new imaging technique and normal values of regional cerebrovascular reserve capacity may provide information about the pathophysiology and surgical indication in patient with occlusive cerebrovascular disease.