Variations in Structural MRI Quality Significantly Impact Commonly-Used Measures of Brain Anatomy

Abstract Subject motion can introduce noise into neuroimaging data and result in biased estimations of brain structure. In-scanner motion can compromise data quality in a number of ways and varies widely across developmental and clinical populations. However, quantification of structural image quality is often limited to proxy and indirect measures gathered from functional scans; this may be missing true differences related to these potential artifacts. In this study, we take advantage of novel informatic tools, the CAT12 toolbox, to directly measure image quality from T1-weighted images to understand if these measures of image quality: 1) relate to rigorous quality-control checks visually completed by human raters; 2) are associated with sociodemographic variables of interest; 3) influence regional estimates of cortical thickness and subcortical volumes from the commonly-used Freesurfer tool suite. We leverage public-access data that includes a community-based sample of children and adolescents, spanning a large age-range ( n=388; ages 5-21 ). Interestingly, even after visually inspecting our data, we find image quality significantly impacts derived cortical thickness and subcortical volumes from multiple regions across the brain (~44% of the regions investigated). We believe these results our important for research groups completing structural MRI studies using Freesurfer or other morphometric tools. As such, future studies should consider using direct measures of image quality to minimize the influence of this potential confound in group comparisons or studies focused on individual differences.