Abstract

There are currently no noninvasive imaging methods available for astrogliosis mapping in the brain despite its essential role in the response to many disease states. In an ex vivo human brain study we used diffusion-relaxation MRI to derive a signature of astrogliosis and disentangle it from normative brain at the individual level using machine learning. We developed a within-subject anomaly detection procedure that generates MRI-based astrogliosis maps ex vivo, which were significantly and strongly correlated with co-registered histology. Our findings demonstrated spatial sensitivity and specificity in detecting reactive astrocytes, and could significantly impact the studying of injury, disease, and aging.