Cerebral magnetic resonance imaging and mental and motor function of very low birth weight children at six years of age

In this follow-up study, 20 of a geographically based year cohort of 31 surviving non-disabled VLBW (birthweight < 1500 g) children were examined at six years of age. The aim of the study was to relate cerebral MRI findings to neuro-development in these non-disabled children at six years of age. All MRI scans were evaluated for myelination pattern, periventricular gliosis, ventricular dilation and cortical atrophy. The Peabody motor test and the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) were used in the evaluation of motor, mental and perceptual function. A diagnosis of attention deficit disorder with hyperactivity was made based on the examiner's impression of the child during the examination and based on the parent's history. We found that ten (50 %) of the children had periventricular gliosis, mainly in centrum semiovale (CS) (nine children) and in central occipital white matter (COW) (six children). Gliosis in CS was related to lower scores on the Peabody gross motor test for locomotion, indicating involvement of corticospinal tracts. Additional gliosis in COW was related to both fine motor and gross motor impairments. We speculate that this indicates damage to both motor and visual pathways, affecting eye-hand coordination and balance function. No relationship between MRI deviations at six years and mental function based on performance, verbal and total IQ scores was found. However, there was a significant relationship between periventricular gliosis in COW and CS and low scores on the WPPSI performance subtests: Picture completion test and Block design test. This may indicate visual and spatial perception problems, caused by damage to posterior visual pathways and occipito-thalamic tracts dealing with visuo-motor integration.