Structural changes of the corpus callosum in mild cognitive impairment and Alzheimer's disease.
BACKGROUND
Although previous studies demonstrate significant atrophy of the corpus callosum (CC) in patients with Alzheimer's disease (AD), CC alterations in mild cognitive impairment have not been investigated yet.


METHODS
21 subjects with mild cognitive impairment, 10 with AD and 21 healthy controls were investigated using magnetic resonance imaging. In the mid-sagittal slice the CC was traced manually. Additionally, voxel-based morphometry (VBM) was performed.


RESULTS
The CC was significantly smaller in patients with AD compared to healthy controls in both manual tracing and VBM. The atrophy was prominent in rostral parts of the CC. In subjects with mild cognitive impairment, the two rostral CC segments were smaller compared to controls when manually traced. In contrast, VBM revealed no significant difference between subjects with mild cognitive impairment and controls.


CONCLUSIONS
Manual tracing was more sensitive in detecting discrete structural CC changes than VBM. Alterations of the CC in mild cognitive impairment rank in between normal aging and AD, supporting the hypothesis that mild cognitive impairment most often represents a preclinical stage of AD.
Thomann
Philipp A
PA
Section of Geriatric Psychiatry, University of Heidelberg, Germany.
Wustenberg
Torsten
T
Pantel
Johannes
J
Essig
Marco
M
Schroder
Johannes
J
D000368:Aged; D000544:Alzheimer Disease / Q000150:complications* / Q000473:pathology*; D001284:Atrophy / Q000473:pathology; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology*; D003337:Corpus Callosum / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male