A framework for abnormality detection in developing white matter in utero, applied to fetuses with Congenital Heart Disease

Motivation: In utero neurodevelopment is complex and not well understood, particularly in fetuses with Congenital Heart Disease. Goal(s): Normatively model microstructural maturation in transient fetal compartmentsApproach: Diffusion MRI was acquired in a healthy control cohort of 235 fetuses (22–37 weeks gestation). White matter bundles were estimated and divided into cross-sections. Gaussian Process Regression models were fit to diffusion metrics in each cross-section, and Z-scores calculated along the tract for 26 fetuses with CHD. Results: We observe gradients of change, highlighting abnormal regions along the white matter unique to each subject. We did not find consistent patterns or associations with a specific diagnosis. Impact: We establish normative trajectories in diffusion MR signal at the level of individual fetal brain compartments that reflect developing microstructure, improving understanding of dynamic fetal brain development and allowing us to predict deviations from the norm.