Single photon emission tomography in Alzheimer's disease. A longitudinal study of changes in relative regional cerebral blood flow

Relative regional cerebral blood (rCBF) was measured in 10 patients fulfilling NINCDS-ADRDA criteria for Alzheimer's disease using Tc-99m-HMPAO single photon emission tomography (SPET). In comparison with 11 age-matched control subjects, relative rCBF was reduced in lateral and medial temporal areas. SPET was repeated after 12-18 months. Relative rCBF fell significantly in the frontal and anterior and posterior parietal areas. Significant changes in left/right asymmetry were found in the frontal and posterior parietal areas suggestinga greater reduction in left hemisphere rCBF. There were few associations between relative rCBF and neuropsychological test performance.