An End-to-End Deep Learning Framework for Alzheimer's Disease Diagnosis by Using Multi-site and Multi-modal MRI Data
摘要
Alzheimer’s disease (AD) is an irreversible neurodegenerative disorder, and the early diagnosis is crucial for prognosis and delaying progression. Multi-modal neuroimaging, particularly T1-weighted (T1w) magnetic resonance imaging (MRI) and diffusion MRI (dMRI), has been widely adopted for the early diagnosis of AD. T1w MRI captures cortical atrophy patterns, while dMRI reveals microstructural degeneration (e.g., myelin damage and axonal loss), with both modalities demonstrating strong diagnostic potential and high inter-modal correlation. Existing multi-modal deep learning models benefit from large-scale, multi-site datasets, they often neglect the site-specific biases that may compromise model performance. Meanwhile, image-level harmonization approaches are generally challenging to integrate directly into diagnostic pipelines and are limited in their ability to handle multi-modal data effectively. To address this issue, we propose an end-to-end deep learning framework for Alzheimer's Disease diagnosis by using multi-site and multi-modal MRI data, which includes an multi-site adversarial harmonization module (MAHM) and a mild cognitive impairment (MCI) enhancement module (MCIEM). Specifically, MAHM mitigates site-specific data shifts by aligning data from different sites to a pseudo target domain, while adversarially preserving the model’s ability to recognize site-specific features, thus enhancing its domain adaptation capabilities. Additionally, the MCIEM includes feature-level adaptive boundary loss and a classifier-level penalty term, which are used to increase the margin between MCI and Natural Control (NC). In summary, our framework mitigates site-related biases in multi-site MRI data, improving diagnostic accuracy. Evaluated on a multi-site dataset MCADI (N = 860, 7 sites) with T1w MRI and dMRI, it achieved advanced performance in NC/MCI/AD classification, outperforming existing methods. Code is publicly available at https://github.com/AI4DMR/3MAD .