Evaluation of the Size and Area of the Corpus Callosum with the Osiris Method in Alzheimer’s Disease

Abstract

Background/Objective: Significant corpus callosum (CC) atrophy has been demonstrated in patients with Alzheimer’s disease (AD). The aim of this study is to evaluate the size and the area of the CC with the Osiris method. The correlation between the CC measurements and Mini-Mental Status Examination (MMSE) scores in AD patients was also investigated. Methods: The results of the topographic measurements included the cross-sectional area of entire CC, body, rostral portion of the genu and splenium from a midsagittal magnetic resonance imaging section. The results of the topographic measurements of CC on MRI with the Osiris method were compared between AD (n = 29) and control subjects (n = 27). Results: In AD patients the mean value of the splenium was 9.2 ± 1.5 mm, the width of the CC body was 3.9 ± 0.2 mm, the rostral portion of the genu was 7.9 ± 0.2 mm, and the total CC area was 47.2 ± 0.9 mm². In the control group the mean values were 12.2 ± 2.1 mm, 5.9 ± 0.2 mm, 11.2 ± 0.2 mm and 56.1 ± 0.6 mm², respectively. Significant reduction was detected in the splenium, the CC body and the rostral part of the genu and CC area in AD patients. The MMSE score was 18.9 ± 4.5 in the AD patients and 29.1 ± 0.9 in the control subjects. A significant positive correlation between the MMSE scores and each CC measurement was seen in the AD patients. Conclusion: The results of this study suggest that callosal atrophy in AD may suggest the severity of the disease. The Osiris method for CC measurements may be used as an easy and reliable technique to assess the severity of the disease.