Project summary/abstract
Children and adolescents have the highest rate of traumatic brain injury (TBI) in the general population, but
current tools for examining structural and functional deficits from MR data have several key limitations. First,
there is no gold standard procedure for considering lesions in imaging analysis, and second, existing tools
have been built on adult populations. We propose to develop a workflow that addresses both of these issues
and supports the extension of novel tools for advanced, multimodal analysis, and to use that workflow to
identify factors associated with outcome. Personalized Profiles of Pathology (P3) will include registration to
age-appropriate templates and lesion segmentation, allowing for voxelwise lesion symptom mapping,
morphometric analyses, shape analysis, and network diffusion modeling as part of the package, with options
for longitudinal analysis as well. This workflow will include and extend novel pipelines. Voxelwise lesion
symptom mapping examines the correspondence between lesion location and specific symptoms, but has
been underpowered in existing applications. Network diffusion modeling uses diffusion MRI data from healthy
individuals to model the spread of pathology. While this is currently used on chronically injured patients to
estimate the epicenter of injury, in this proposal, longitudinal data will be used to validate predictions of
pathology spread. Tract-wise statistical analysis similarly uses healthy data to predict the degree of
disconnection based on lesion location. Symmetric multivariate linear reduction reduces high dimensional
imaging, cognitive, and clinical data to components, revealing patterns of disruption. By including all of these
individual approaches across multiple sites, P3 will allow for multi-modal examination of the impact of TBI on
pediatric patients with greater statistical power. In Aim 1, we will develop and test P3 on cohorts from eight
sites. With input from clinical experts in neurology, rehabilitation, neuropsychology, radiology, and brain
development, and technical expertise from mathematics, computer science, and neuroimaging analytics, we
will ensure that P3 is statistically and computationally valid and clinically relevant. In Aim 2, we will extract
common neuropsychological endpoints from disparate scales across cohorts and use these measures with
brain metrics generated by P3 to determine factors associated with outcome and identify subgroups within the
patient population. In Aim 3, we will distribute P3 to a network of beta-testing sites to run locally, allowing for
further improvement and validation, and disseminate P3 to the research community. Through meta-analysis or
harmonization paired with mega-analysis, we will combine effects across sites and examine consistency in
effect size, location, and direction. Education will occur through tutorials at national and international
conferences, site visits, and through written documentation. P3 will be made available online, with continuing
support from the development team. The ultimate goal of P3 is to better understand heterogeneity in
post-injury outcome to inform future treatment development.