[MRI study of the brain in aged volunteers: T2 high signal intensity lesions and high cortical function].

In order to characterize age-related and chronological changes of the brain, longitudinal studies of aged volunteers were conducted using computed tomography since 1982. The present paper discusses correlations between brain function and findings of MR images which were obtained a using 1.5 T superconductive MR instrument since 1989. A total of 118 volunteers aged 60 to 88 years old with a mean age of 75.0 +/- 6.7 participated in the study, which consisted of MRI, EEG recording, the Benton Visual Retention Test and a medical interview. Subjects with a past history or clinical evidence of CVD, head trauma or dementia were excluded from the study. Incidence of T2 high signal intensity lesions increased with age. Some showing T1 low signal intensity in the same lesion were considered to be lacunar infarction, over all incidence of which was 24.6%. Numbers of correct responses on the BVRT showed a negative correlation with numbers of T2 high signal intensity lesions. Although the aged volunteers in the present study could achieve all activity of daily living without any trouble, high cortical function evaluated by visuoperceptual performance of BVRT was somewhat disturbed in participants with multiple T2 high signal intensity lesions. Brain atrophy seems to be more advanced in groups with T2 hyper intensity lesions than in the group without them. These findings may support the notion that T2 high signal intensity lesions are not merely an index of ageing but pathologic lesions accompanied with senescence, although further studies including clinicopathological correlation are necessary to establish this concept.