Corpus callosum shape changes in early Alzheimer’s disease: an MRI study using the OASIS brain database

• Published in: Brain Structure and Function Vol. 219; no. 1; pp. 343 - 352
• Main Authors: Ardekani, Babak A., Bachman, Alvin H., Figarsky, Khadija, Sidtis, John J.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.01.2014; Springer Nature B.V
• Subjects: Age; Age Factors; Aged; Aged, 80 and over; Alzheimer Disease - pathology; Alzheimer's disease; Analysis of Variance; Biomedical and Life Sciences; Biomedicine; Brain; Cell Biology; Corpus Callosum - pathology; Cross-Sectional Studies; Databases, Factual - statistics & numerical data; Disease Progression; Female; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Middle Aged; Neurology; Neurosciences; NMR; Nuclear magnetic resonance; Original Article; Psychiatric Status Rating Scales; Sex Factors; Statistics as Topic; Brain; Shape analysis; Alzheimer’s disease; Magnetic resonance imaging; Corpus callosum
• ISSN: 1863-2653; 1863-2661; 0340-2061
• DOI: 10.1007/s00429-013-0503-0

The corpus callosum (CC) is the largest fiber bundle connecting the left and right cerebral hemispheres. It has been a region examined extensively for indications of various pathologies, including Alzheimer’s disease (AD). Almost all previous studies of the CC in AD have been concerned with its size , particularly its mid-sagittal cross-sectional area (CCA). In this study, we show that the CC shape , characterized by its circularity (CIR), may be affected more profoundly than its size in early AD. MRI scans ( n  = 196) were obtained from the publicly available Open Access Series of Imaging Studies database. The CC cross-sectional region on the mid-sagittal section of the brain was automatically segmented using a novel algorithm. The CCA and CIR were compared in 98 normal controls (NC) subjects, 70 patients with very mild AD (AD-VM), and 28 patients with mild AD (AD-M). Statistical analysis of covariance controlling for age and intracranial capacity showed that both the CIR and the CCA were significantly reduced in the AD-VM group relative to the NC group (CIR: p  = 0.004; CCA: p  = 0.005). However, only the CIR was significantly different between the AD-M and AD-VM groups ( p  = 0.006) being smaller in the former. The CCA was not significantly different between the AD-M and AD-VM groups. The results suggest that CC shape may be a more sensitive marker than its size for monitoring the progression of AD. In order to facilitate independent analyses, the CC segmentations and the CCA and CIR data used in this study have been made publicly available ( http://www.nitrc.org/projects/art ).