Quantitative MR study of corpus callosum in Alzheimer's disease and vascular dementia

Objective: To investigate the total area and different portions of corpus callosum in Alzheimer's disease (AD), vascular dementia (VD), and normal contrast (NC). Methods: 70 cases which contained 26 AD patients, 14 VD patients, and 30 age-matched control subjects received MRI. Total area and five regional (anterior, anterior-middle, middle, posterior-middle, and posterior portions) thickness of corpus callosum were measured on T1-weighted mid-sagittal slices. Results: The standardized total area of corpus callosum in AD, VD and NC groups were (3.55±0.52) cm2, (3.48±0.90) cm2, and (4.23±0.43) cm2, respectively. And the five regional thickness of corpus callosum in AD, VD and NC groups were: AD (5.34 ± 1.14) mm, VD (5.53±1.86) mm, NC(7.06±1.11) mm; AD (2.53±0.62) mm, VD (2.53±0.86) mm, NC(3.46 ± 0.66) mm; AD (2.85±0.54) mm, VD(2.84±1.04)mm, NC (3.54±0.61) mm; AD (2.01±0.50) mm, VD (1.90±0.72) mm, NC (2.49±0.65) mm; AD(5.46 ± 0.96) mm, VD (5.22±1.40) mm, NC(6.82±1.02)mm, respectively. The five regional atrophy rate of corpus callosum in AD and VD were: AD (24.36±16.13)%, VD(21.70±26.35)%; AD(26.75±17.97)%, VD(26.78±24.90)%; AD(19.60±15.30)%, VD(19.72±29.24)%; AD(19.17±20.35)%, VD(23.79±28.99)%; AD(20.00±13.96)%, VD (23.44±20.60)% respectively. Both the standardized total area and five regional thickness of corpus callosum in AD and VD groups were significantly decreased comparing with those of NC group (P<0.01). No differences were found between AD and VD groups (P>0.05). There were no statistical differences among the five regional atrophy rate of corpus callosum both in AD and VD groups (P>0.05). Conclusion: Significant corpus callosum atrophy can be detected in both AD and VD patients, indicating that interhemispheric cortico-cortical disconnections may contribute to AD and VD