Functional and structural connectivity of the brain in very preterm babies: relationship with gestational age and body and brain growth

Background Structural and functional changes of the brain have been reported in premature babies. Objective To evaluate the relationship of functional and structural connectivity with gestational age, body growth and brain maturation in very preterm babies. Materials and methods We studied 18 very preterm babies (gestational age: mean ± standard deviation, 29.7±1.7 weeks). We examined functional connectivity by multivariate pattern analysis of resting-state functional MRI data. We assessed structural connectivity by analysis of diffusion tensor imaging data and probabilistic tractography. Results The average functional connectivity of the medial orbitofrontal cortex with the rest of the brain was positively associated with gestational age ( P <0.001). Fractional anisotropy of the right inferior fronto-occipital fasciculus was positively associated with head circumference at term-equivalent age. Structural connectivity of the inferior fronto-occipital fasciculus with the medial orbitofrontal cortex was positively associated with head circumference at term-equivalent age. Body weight at term-equivalent age was the only independent predictor of average structural connectivity of the medial orbitofrontal cortex with the rest of the brain ( P =0.020). Conclusion Structural and functional connectivity of the medial orbitofrontal cortex with the rest of the brain depend on body growth and degree of prematurity, respectively.