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arXiv · 2601.21076

Multi-modal Imputation for Alzheimer's Disease Classification

Abhijith Shaji·Tamoghna Chattopadhyay·Sophia I. Thomopoulos·Greg Ver Steeg·Paul M. Thompson·Jose-Luis Ambite
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Abstract

Deep learning has been successful in predicting neurodegenerative disorders, such as Alzheimer's disease, from magnetic resonance imaging (MRI). Combining multiple imaging modalities, such as T1-weighted (T1) and diffusion-weighted imaging (DWI) scans, can increase diagnostic performance. However, complete multimodal datasets are not always available. We use a conditional denoising diffusion probabilistic model to impute missing DWI scans from T1 scans. We perform extensive experiments to evaluate whether such imputation improves the accuracy of uni-modal and bi-modal deep learning models for 3-way Alzheimer's disease classification-cognitively normal, mild cognitive impairment, and Alzheimer's disease. We observe improvements in several metrics, particularly those sensitive to minority classes, for several imputation configurations.

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Abhijith Shaji, Tamoghna Chattopadhyay, Sophia I. Thomopoulos, Greg Ver Steeg, Paul M. Thompson, Jose-Luis Ambite. 2026-01-28. Multi-modal Imputation for Alzheimer's Disease Classification. https://arxiv.org/abs/2601.21076

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