MRI at term equivalent age for predicting long-term neurodevelopmental outcome in preterm infants - a cohort study

Purpose: Preterm infants are at increased risk of adverse neurodevelopmental outcome (NDO). Cranial ultrasound has limited predictability. The purpose of the study is to evaluate whether magnetic resonance imaging (MRI) done at term equivalent age (TEA) predicts NDO at 18-22 months of corrected gestational age (CGA).Materials and methods: This cohort study of preterm infants born at ≤32 weeks of gestation and/or birth weight <1500 grams between April 2011 and August 2012 was conducted in a tertiary care institute in India. MRI done at TEA was reported using objective scoring. NDO at 18-22-month CGA was assessed using Bayley Scale of Infant Development (BSID) version III. Composite score (CS) < 85 in motor, language, or cognition domain was taken as adverse NDO. Association between individual MRI subscores and NDO was evaluated using multiple linear regressions by backward elimination method. Validity of MRI abnormality in predicting adverse NDO was assessed.Results: Out of 94 infants who had MRI at TEA, 56 (60%) underwent BSID III. Mean gestational age was 29.8 ± 2.1 weeks. Median CS of all domains was lower with higher total MRI score. Predictive accuracy for various subscores ranged from 55 to 73%. By multiple regression analysis, signal abnormality was associated with motor delay (β -8.4; p .02) and cystic white matter (WM) changes with motor delay (β -7.3; p .003) and cognitive delay (β -6.1; p .005).Conclusions: Although specificity and negative predictive value were moderate to high across all subscores in MRI to predict the NDO, the accuracy has been only low to moderate, which limits its use as sole predictor.