196 Widespread White Matter Damage is Seen on DTI in Young Adults Born Preterm with Very Low Birth Weight (VLBW)

Abstract

Background and aims: Perinatal brain injury in very low birth weight (VLBW) preterms is associated with permanent changes in white matter integrity and connectivity, and to neurodevelopmental problems including cognitive deficits. The aim of study was to investigate whether being born with VLBW leads to white matter damage that persist into adulthood, and to examine the relationship between white matter integrity and perinatal data and IQ in the VLBW group. Methods: Forty-nine VLBW young adults and 59 term controls were scanned at 1.5 T at ages 18-22 with DTI. Voxelwise maps of fractional anisotropy (FA) were calculated and Tract-Based Spatial Statistics was carried out to test for voxelwise differences between groups. Cognitive function was assessed with WAIS-III. The relationships between FA and total IQ and perinatal variables were explored. Results: In VLBW adults all major central and posterior white matter tracts had reduced FA, mainly caused by an increase in the two lowest eigenvalues. FA correlated positively with birth weight and negatively with number of days on mechanical ventilator and in NICU. More than half of the VLBW subjects obtained a subnormal IQ score. The FA-IQ correlation analyses demonstrated positive correlations between FA and IQ in regions including corpus callosum and long and short association tracts. Conclusions: Preterm birth with VLBW results in long-term irreversible changes in white matter microstructure that relate to inferior IQ in VLBW young adults. Lower birth weight and perinatal problems seem to have permanent negative effects on white matter integrity.