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bioRxiv · 10.1101/2020.08.18.256321

A Large-scale Comparison of Cortical and Subcortical Structural Segmentation Methods in Alzheimer's Disease: a Statistical Approach

Zamani, J.·Sadr, A.·Javadi, A.-H.
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Abstract

BackgroundAlzheimers disease (AD) is a neurodegenerative disease that leads to anatomical atrophy, as evidenced by magnetic resonance imaging (MRI). Automated segmentation methods are developed to help with the segmentation of different brain areas. However, their reliability has yet to be fully investigated. To have a more comprehensive understanding of the distribution of changes in AD, as well as investigating the reliability of different segmentation methods, in this study we compared volumes of cortical and subcortical brain segments, using automated segmentation methods in more than 60 areas between AD and healthy controls (HC). MethodsA total of 44 MRI images (22 AD and 22 HC, 50% females) were taken from the minimal interval resonance imaging in Alzheimers disease (MIRIAD) dataset. HIPS, volBrain, CAT and BrainSuite segmentation methods were used for the subfields of hippocampus, and the rest of the brain. ResultsWhile HIPS, volBrain and CAT showed strong conformity with the past literature, BrainSuite misclassified several brain areas. Additionally, the volume of the brain areas that successfully discriminated between AD and HC showed a correlation with mini mental state examination (MMSE) scores. The two methods of volBrain and CAT showed a very strong correlation. These two methods, however, did not correlate with BrainSuite. ConclusionOur results showed that automated segmentation methods HIPS, volBrain and CAT can be used in the classification of AD and HC. This is an indication that such methods can be used to inform researchers and clinicians of underlying mechanisms and progression of AD.

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Zamani, J., Sadr, A., Javadi, A.-H.. 2020-08-19. A Large-scale Comparison of Cortical and Subcortical Structural Segmentation Methods in Alzheimer's Disease: a Statistical Approach. https://doi.org/10.1101/2020.08.18.256321

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