Cranial ultrasonography and transfontanellar Doppler in premature neonates (24-32 weeks of gestation): dynamic evolution and association with a severe adverse neurological outcome at hospital discharge in the Aquitaine cohort, 2003-2005

OBJECTIVE: To correlate the short-term neurological outcome of early cerebral abnormalities using cranial ultrasonography (US) in premature newborns at their hospital discharge.

METHODS: Each newborn born <33 weeks of gestational age (GA) included in a prospective cohort benefited of 3 US: two early in the first week of life (D3 and D8) and one later (Months 1-2) standardized US pulsed Doppler. A US abnormality was ≥one morphologic abnormality (moderate: intra-ventricular hemorrhage (IVH) grades 1-2; severe: IVH 3-4, periventricular leukomalacia, persistent flares). Correlates of having a severe adverse neurological outcome were analyzed using a stepwise backward logistic regression adjusted model with gestational age, early cerebral abnormality at Days 3-8, velocity and with variables with correlation probabilities with p<0.25 in the univariate analysis among occurring co-morbidity events previously defined. Two adjusted logistic regression analyses were conducted including or not velocity data because of missing information.

RESULTS: Among 452 premature included, 11.3% did not have an early US, 74.8% had a normal early US, 13.9% ≥one early morphological US abnormality (10.0% moderate, 3.9% severe). At hospital discharge, 40% were still alive with a normal late US, 33% alive with ≥one late morphological US abnormality (10% moderate, 23% severe), and 10% died. Adjusted correlates of a late US severe abnormality or a neurological related death at hospital discharge were: early US abnormality (aOR: 8.7, 95% CI: 2.3-33.6), GA<29 weeks (aOR: 2.8 95% CI: 1.4-5.4).

CONCLUSION: This study shows that early US morphological abnormalities increase significantly when the GA decreases and is highly predictive of the occurrence of a further late US severe abnormality or neurological related death at hospital discharge.