Whole Mouse Beta-amyloid Plaque Loading Map via Low Rank Based Orthogonal Projection and Spatial-spectrum Detector Using High-resolution Quantitative Susceptibility Mapping

Motivation: Low-rank and sparsity matrix decomposition (LRaSMD) combined with orthogonal projection effectively removes complex background, making beta-amyloid plaque (Aβ) detection straightforward. Goal(s): A whole-mouse beta-amyloid plaque loading map provides a more accurate and comprehensive assessment of Alzheimer's disease progression. Approach: Multi-echo gradient echo images of 5xFAD female mice (ages 2, 4, 7.5, and 12 months; 5, 6, 7, and 7 mice per group) were acquired at 9.4T. QSM images were then calculated, followed by LRaSMD and Aβ detection. Results: The Aβ plaques loading are dramatically different among different stages, aligning with the progression observed at each stage. Impact: A 3D whole-brain image of Aβ plaques has the potential to serve as an imaging model for accurate and comprehensive assessment of Alzheimer's disease progression at different stages.