CALLOSAL ATROPHY PARALLELS DECREASED CORTICAL OXYGEN-METABOLISM AND NEUROPSYCHOLOGICAL IMPAIRMENT IN ALZHEIMERS-DISEASE

Objective.-To evaluate the relationship of corpus callosum atrophy to cerebral cortical oxygen metabolism and cognitive function in patients with Alzheimer's disease. Design.-Prospective clinicoradiologic correlation with magnetic resonance imaging and positron emission tomography. Setting.-A university hospital. Patients, Participants.-Ten right-handed male patients with Alzheimer's disease, aged 46 to 70 years (mean +/- SD 57 +/- 6 years), and 14 age- and sex-matched right-handed control subjects. Main Outcome Measures.-The midsagittal corpus callosum areas (on T1-weighted magnetic resonance images), cerebral metabolic rate of oxygen (measured with positron emission tomography using the oxygen-15 steady-state technique), and the IQs of the Wechsler Adult Intelligence Scale. Results.-Compared with control subjects, the patients had significantly decreased callosal areas with a posterior predominance of the degree of atrophy. The area of anterior and posterior halves of the corpus callosum had a significant correlation with the value of oxygen metabolism in the frontal and parietotemporo-occipital association cortices, respectively. The total area of the corpus callosum was significantly related to the total and verbal IQs of the Wechsler Adult intelligence Scale. Conclusion.-Atrophy of corpus callosum reflects the severity and pattern of cortical damage associated with hypometabolism and cognitive impairment in Alzheimer's disease.