Corpus callosum atrophy in patients with leukoaraiosis may indicate global cognitive impairment

Background and Purpose-The extent of white matter high-intensity lesions (WMLs) on T2-weighted MR images may be an indicator of cognitive impairment, especially impairment related to frontal lobe dysfunction. However, it is unclear whether the extent of WMLs is an independent predictor of cognitive impairment. In patients with extensive WMLs, atrophy of the corpus callosum may be an important predictor of global cognitive impairment. The purpose of this study was to investigate the relation of the extent of WMLs and callosal size with cognitive functions in a patient population with a wide range of extent of WMLs. Methods-We studied 62 patients, aged 49 to 86 years, who underwent MRT because of neurological symptoms and were diagnosed as having lacunar stroke or no specific neurological disease: 28 with lacunar infarcts and 34. without. Multivariate analysis was used to test the independent predictive value of patient age, sex, educational level, other medical illness, lacunar infarct, corpus callosum area, and extent of WMLs with respect to scores of Mini-Mental State Examination or verbal fluency task. Results-Only callosal size and age were significant independent predictors of the scores of the Mini-Mental State Examination, while only the extent of WMLs was an independent predictor of the score of the verbal fluency task. Conclusions-Callosal atrophy may be an important predictor of global cognitive impairment in patients with WMLs, whereas the extent of WMLs per se may be related to impairment of frontal lobe function independent of callosal atrophy.