Multimodal neuroimaging plays an indispensable role in the diagnosis, monitoring, and therapeutic evaluation of monoclonal antibody (mAb) therapies for Alzheimer's disease (AD). Structural MRI (sMRI) enables early detection of cerebral atrophy and amyloid-related imaging abnormalities (ARIA), a critical adverse effect associated with anti-Aβ immunotherapies. Positron emission tomography (PET) provides direct visualization and quantification of Aβ plaque clearance, serving as an objective biomark