Early neuromotor development of high risk infants - Gross motor function in preterm and full-term born infants

This thesis is the result of 20 years follow-up of preterm and full-term born ‘graduates’ of the neonatal intensive care unit of the Wilhelmina Children’s Hospital, Utrecht. The aim was to answer questions that arose during admission and follow-up assessments. Typical gross motor development of preterm infants Gross motor development of 800 preterm infants (gestational age [GA] <32 weeks) was assessed when the children were between 1 and 19 months corrected age (CA). The scores were significantly lower compared to norm-referenced values, most likely reflecting a variant of typical gross motor development. Prediction of neuromotor outcome based on brain imaging Sequential cranial ultrasonography (cUS) until term-equivalent age (TEA) combined with conventional magnetic resonance imaging (MRI) at TEA enables us to predict motor outcome in infants born preterm as long as experienced examiners interpret the images. Persistent normal cranial ultrasonography (cUS) is predictive of a normal outcome, whereas major brain injuries can accurately predict cerebral palsy (CP). Also in infants born full-term, cUS and MRI (including diffusion-weighted imaging) are effective tools to predict CP. Specific neuromotor developmental pathways We examined the association between PVL grade and gross motor functional abilities in 59 children with CP born preterm (GA ≤34 weeks) at four timepoints in their life (between a mean of 9.5 months CA and a median of 7.5 years). Infants’ gross motor abilities varied depending on the severity of PVL. Children with PVL grade I–II were able to walk independently, whereas most infants with c-PVL grade III–V did not achieve the potential to walk. Stability of gross motor function became more robust after the first year of age. In infants born preterm (GA