Authors: Albert Isaacs, MD; Joshua Shimony, MD, PhD; Rowland Han, MD, MSc; Sophie Zimbalist, BS; Dimitrios Alexopoulos, MS; Jeffrey Neil, MD, PhD; Rachel Lean, PhD; Cynthia Rogers, MD, PhD; Yan Yan, MD, PhD; Christopher Smyser, MD; David Limbrick Jr., MD, PhD (Calgary, Canada)
Injury to the preterm lateral ventricular perimeter (LVP), which houses the neural stem cells for cortical development plays a critical role in the neurological sequelae of intraventricular hemorrhage (IVH) and post-hemorrhagic hydrocephalus (PHH). This study utilizes diffusion MRI (dMRI) to characterize the microstructural effects of IVH/PHH of prematurity in the LVP and the relationship between ventricular size and LVP injury.
56 full-term-born infants (FT), 67 very preterm infants without brain injury (VPT), 21 VPT infants with high-grade IVH that did not develop hydrocephalus (HG-IVH) and 13 HG-IVH infants treated for PHH (PHH) underwent dMRI studies. Differences in their dMRI measures from the LVP, as well as segmented frontal-occipital horn perimeters (FOHP), and ventricular size-dMRI correlations were assessed.
Fractional anisotropy (FA) was observed in the order of PHHHG-IVH>VPT>FT (p<.001). Ventricular size correlated negatively with FA, and positively with MD and RD (p<.001). No between-group differences, or ventricular size-dMRI correlations were found for AD.
HG-IVH and PHH were associated with the most aberrant LVP/FOHP changes when compared to controls, with the most prominent abnormalities among the PHH group, especially in the FOHP. The larger the ventricles size, the greater the magnitude of dMRI-measured injury, especially in the FOHP. These findings support that LVP/FOHP injury occur in IVH/PHH, as an antecedent/contributing factor that exposes periventricular white matter injury and downstream neuropsychological deficits in affected infants. Further, LVP/FOHP dMRI assessment may be valuable biomarkers of IVH/PHH for future studies directed at improving the clinical management of these conditions.