Neurodevelopmental impact of early diagnostic imaging in preterm infants: quantifying risk and the role of point-of-care ultrasound.

BACKGROUND

Medical imaging is essential in neonatal intensive care units (NICUs), particularly for the management of preterm infants. However, concerns persist regarding the neurodevelopmental impact of repeated low-dose radiation exposure. This study aimed to investigate whether cumulative x-ray exposure in the first month of life is associated with neurodevelopmental outcomes in preterm infants.

METHODS

We conducted a retrospective chart review of preterm infants (<34 weeks gestation) admitted to the Level IIIB NICU at Tufts Medical Center. Infants were included if they had at least one x-ray within the first 24 h of life and were followed consistently at the neurodevelopmental clinic till 12-18 months corrected age. Exclusion criteria included major congenital anomalies, severe perinatal complications and loss to follow-up. Cumulative x-ray exposure was recorded at Day 1, Day 7, and Month 1. Neurodevelopment was assessed using Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). Multiple linear regression analyses were used to assess associations, adjusting for gestational age, birth weight, comorbidities and SNAPPE-II scores.

RESULTS

Among 53 infants, cumulative imaging by Day 7 and Month 1 was significantly associated with lower Bayley-III motor and cognitive scores. Each additional x-ray by Day 7 was associated with a 1.38-point decline in motor scores ( < 0.001) and a 0.89-point decline in cognitive scores ( = 0.046). These associations persisted at Month 1. No significant effects were found for imaging on Day 1. Language outcomes showed non-significant downward trends.

CONCLUSION

Frequent x-ray exposure in the first month of life may be associated with worse motor and cognitive development in preterm infants. These findings suggest the need for weight-based diagnostic reference levels in NICUs and support incorporation of alternative imaging such as point of care ultrasound (POCUS into routine neonatal intensive care.