Brain MRI volumetrics

Brain MRI volumetrics uses structural magnetic resonance imaging to quantify the volume of specific brain regions — most notably the hippocampus, lateral ventricles and total grey- and white-matter — as well as cortical thickness across parcellated regions. Automated analysis pipelines such as FreeSurfer and the GPU-accelerated FastSurfer process T1-weighted images to generate normative deviation scores; larger ventricular volumes and reduced hippocampal or cortical thickness are established markers of accelerated brain ageing, with rates of atrophy increasing substantially after age 60. Cross-sectional population studies such as UK Biobank have mapped trajectories of regional volume loss against age, lifestyle factors and disease risk, enabling the concept of a 'brain age gap' — the difference between estimated brain age and chronological age — as a potential biomarker for neurodegenerative risk and cognitive resilience.