[Aging changes of cerebral high intensity areas on T2-weighted MRI--a study in medical checkup patients]

To determine normal aging process of the brain, cerebral T2-weighted MRI was evaluated in 400 healthy individuals who visited our hospital for routine medical checkups. The results are summarized as follows. 1) High intensity areas (measuring 2 mm x 2 mm or more) were observed most frequently in the cerebral white matter including the corona radiata (CR). The incidence of these areas increased linearly with age, and approached about 50% in the patients of the seventh decade. 2) High intensity areas in the basal ganglia (BG) were the second commonest. High intensity areas were rarely seen in the thalamus (TH) and pontine base (PO). 3) High intensity areas were confined to the CR (66.9%) in the majority of the cases, while there were few cases having these areas restricted to the BG, TH and PO; that is, most of them were accompanied by additional high intensity areas in the CR. 4) Periventricular hyperintensity areas increased in size with age, and were prominent in those who had multiple or large high intensity areas in the CR, or those who had signal hyperintensity in the BG, TH or PO.