Feature similarity gradients detect alterations in the neonatal cortex associated with preterm birth

Abstract

The early life environment programmes cortical architecture and cognition across the life course. A measure of cortical organisation that integrates information from multi-modal MRI and is unbound by arbitrary parcellations has proven elusive, which hampers efforts to uncover the perinatal origins of cortical health. Here, we use the Vogt-Bailey index to provide a fine-grained description of regional homogeneities and sharp variations in cortical microstructure based on feature gradients, and we investigate the impact of being born preterm on cortical development. Preterm infants have a homogeneous microstructure in temporal and occipital lobes, and the medial parietal, cingulate, and frontal cortices, compared with term infants. These observations replicated across two independent datasets and were robust to differences that remain in the data after matching samples and alignment of processing and quality control strategies. We conclude that cortical microstructural architecture is altered in preterm infants in a spatially distributed rather than localised fashion.

Harmonizing multisite neonatal diffusion-weighted brain MRI data for developmental neuroscience

“…When adjusting for GA at scan, GA at birth and sex, there were no significant effect of site on DTI metric means or histogram widths. When combining data from multiple sites, standardizing preprocessing and quality control strategies can reduce variation between sites, however differences related to data acquisition are likely to impact extracted metrics (Galdi et al, 2024). ComBat has been used to harmonize DTI metric maps from very preterm infants imaged with different sequences on the same MRI system (Parikh et al, 2021), region of interest measures in term and preterm infants (Galdi et al, 2018), and DTI metrics along white matter tractography reconstruction in infants with congenital heart disease (Meyers et al, 2022).…”

“…However, other advanced measures of microstructure such as NODDI (Zhang et al, 2012) or fixel-based metrics (Raffelt et al, 2017) provide different insights into the developing brain and research assessing the impact of ComBat harmonization on these metrics in the neonatal brain is warranted. Finally, using dMRI to assess cortical microstructural development have reported alterations in neonates with congenital heart disease (Kelly et al, 2019) and those born prematurely (Ball et al, 2013;Galdi et al, 2024) and correlations with clinically relevant factors (Kelly et al, 2019;Sullivan et al, 2023). Future studies are required to optimize pipelines for registration and preprocessing, as well as assessing the utility of comBat for multi-centre cortical diffusion research in neonates.…”

Local gradient analysis of human brain function using the Vogt-Bailey Index

“…A modified version was used with diffusion data to study the impact of preterm birth on the homogeneity of tissue microstructure in the neonatal cortex (Galdi et al. 2022 ). Indeed, the methodology underlying the VB algorithm can be adapted to different modalities of data.…”

Local gradient analysis of human brain function using the Vogt-Bailey Index

“…This estimates the algebraic connectivity in volumetric space and then maps the results to the original surface vertices [30]. A modified version was used with diffusion data to study the impact of preterm birth on the homogeneity of tissue microstructure in the neonatal cortex [31].…”