A longitudinal study of fractional anisotropy in white matter of preterm born very low birth weight adolescents and young adults compared to term born controls

Abstract

Preterm born children with very low birth weight (VLBW, birth weight < 1500 g)are at increased risk of perinatal brain damage. Perinatal factors, such as low birthweight and morbidity leading to intensive care treatment and/or mechanical ventilationhave a signicant negative impact on the white matter microstructure. This may resultin permanent deviations in WM microstructure and thereby interfere with normal braindevelopment and function.

By using diusion tensor imaging (DTI) to assess WM microstructure in vivo, ithas been demonstrated that VLBW individuals have a wide spread of WM dierencescompared to term-born controls with normal birth weight. These dierences are generallyseen as lower fractional anisotropy (FA) in several WM tracts. Lower FA in these regionshas been associated with a variety of perceptual, cognitive, motor and mental healthimpairments.

It has been suggested that these dierences in WM microstructure arises from dierencesin brain maturation, with the premature VLBWs lagging behind the controls. Inthis study, regions of interest (ROI) are used to evaluate the longitudinal changes in FA,mean diusivity (MD) and eigenvalues, 1, 2 and 3, in 10 WM regions of DT imagesobtained at age 14, 20 and 23 in a cohort of VLBWs and term-born controls.