Abstract
The choroid plexus (ChP), a highly vascularized epithelial organ within the brain ventricles, sustains cerebrospinal fluid (CSF) production, regulates the blood-CSF barrier (BCSFB), and coordinates neuroimmune responses. Beyond these classical roles, the ChP is increasingly recognized as an active interface within brain clearance pathways, facilitating CSF-interstitial fluid (ISF) exchange and contributing to metabolic waste removal. Structural and functional disruption of the ChP/BCSFB accompanies aging and has been linked to the pathogenesis of neurodegenerative disorders. Magnetic resonance imaging (MRI) provides a powerful, non-invasive platform for in vivo characterization of the ChP. This review summarizes recent advances in MRI techniques tailored to ChP imaging, including quantitative assessments of microstructure, perfusion, permeability, and dynamic water exchange, and highlights their applications in aging and dementia. Converging evidence suggests that MRI-derived indices of ChP integrity are associated with cognitive status and may facilitate early detection and longitudinal monitoring of disease trajectories, particularly in Alzheimer's disease and related dementias (AD/ADRD). Continued development and application of advanced MRI approaches will be essential for further elucidating the role of the ChP in neurodegeneration and for evaluating its potential clinical utility.