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 age (TEA) 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 TEA. 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 TEA 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 TEA 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 TEA 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.