Diffusion tractography and neuromotor outcome in very preterm children with white matter abnormalities

Abstract

Background Moderate-severe white matter abnormality (WMA) in the newborn has been shown to produce persistent disruptions in cerebral connectivity, but does not universally result in neurodevelopmental disability in very preterm (VPT) children. The aims of this hypothesis driven study were to apply diffusion imaging to: 1) examine whether bilateral WMA detected in VPT children in the newborn period can predict microstructural organization at age 7; 2) compare corticospinal tract (CST) and corpus callosum (CC) measures in VPT children at age 7 with neonatal WMA with normal versus impaired motor functioning. Methods Diffusion parameters of the CST and CC were compared between VPT 7-year-olds with (n=20) and without (n=42) bilateral WMA detected in the newborn period. For those with WMA, diffusion parameters were further examined. Results Microstructural organization of CST and CC tracts at age 7 years were altered in VPT children with moderate-severe WMA detected at term equivalent age compared to those without injury. Furthermore, diffusion parameters differed in the CC for children with WMA categorized by motor outcome (N=8). Conclusions WMA on conventional MRI at term equivalent age is associated with altered microstructural organization of the CST and CC at 7 years of age.

Association between corpus callosum development on magnetic resonance imaging and diffusion tensor imaging, and neurodevelopmental outcome in neonates born very preterm

“…In our study, these changes were particularly evident in the posterior part that develops later than the rest of the corpus callosum . In 7‐year‐old children born preterm, abnormal diffusion parameters in the corpus callosum were detected in those with moderate‐to‐severe white matter abnormalities detected at term‐equivalent age . Taken together, these data suggest that the changes observed in our cohort studied from early in life to term‐equivalent age are not transient.…”

Probabilistic maps of the white matter tracts with known associated functions on the neonatal brain atlas: Application to evaluate longitudinal developmental trajectories in term-born and preterm-born infants

“…The histopathological underpinnings of the selective vulnerability of the CC and visual pathway remain unknown (Huang et al, 2006; Trivedi et al, 2009b). Longitudinal analysis that begins at earlier postmenstrual weeks is anticipated to test a hypothesis that the area with rapid growth is vulnerable to the effect of prematurity (Estep et al, 2014). …”

Relationship between characteristics on magnetic resonance imaging and motor outcomes in children with cerebral palsy and white matter injury

“…Clearly, conventional MRI lacks the sensitivity to detect subtle WMI (Lee et al, 2011), and some 'invisible' factor appears to contribute to gross motor function. Research using diffusion parameters has been able to demonstrate correlation between abnormality in individual WM tracts, believed to reflect abnormal microstructural connectivity, and clinical outcomes (Counsell et al, 2008;Estep et al, 2014;Lee et al, 2011). Thus, a brain that looks normal on conventional imaging may still have injury to WM tracts demonstrated using these or other quantitative techniques (Mu et al, 2014;Scheck, Pannek, Fiori, Boyd, & Rose, 2014).…”