Relationships between sequential MRI in the neonatal period and early motor repertoire in very preterm infants

Background Infants born very preterm frequently experience neurodevelopmental challenges. Early detection enables provision of targeted interventions to improve outcomes. Early neonatal and term-equivalent MRI and 3–5-month corrected age (CA) Prechtl Motor Optimality Score — revised (MOS-R) are useful prognostic tools, however structure–function relationships between them are not well established. Methods Infants born <31 weeks' gestation underwent MRI at 32-weeks postmenstrual age and term-equivalent age. Modified Kidokoro MRI scoring generated white matter, cortical grey matter, deep grey matter and cerebellar scores which were summed to produce a global score. Infant MOS-R was assessed from videos recorded at 3–4 months' CA. Relationships between MRI abnormality scores and MOS-R and absent fidgety general movements were modelled using regression analysis. Results Brain MRI was performed at 32-weeks in 249 infants, of whom 221 had term-equivalent MRI and 225 had a MOS-R. For 32-week MRI, white matter, deep grey matter and global scores were related to MOS-R (global βMOS-R = −0.27, 95% confidence interval [CI] −0.46, −0.08; p = 0.006) and absent fidgety movements (global odds ratio = 1.23, 95%CI 1.07, 1.40; p = 0.003). For term-equivalent MRI, white matter and global scores were related to MOS-R (global βMOS-R = −0.26, 95%CI −0.47, −0.06; p = 0.01) and absent fidgety movements (global odds ratio = 1.23, 95%CI 1.05, 1.42; p = 0.008). In multivariable model including global scores from both timepoints, term equivalent MRI scores remained related to MOS-R (βMOS-R = −0.41, 95%CI −0.72, 0.10; p = 0.009). Conclusion Early and term-equivalent MRI are related to MOS-R and general movements assessment. Term MRI global scores are independently related to MOS-R at 3–4 months' corrected age. This has implications for prioritising infants with poorer MRI scores for early assessment and that poorer MOS-R scores may be a manifestation of changes to brain structure and due to preterm birth.