Spontaneous resolution of post-hemorrhagic ventricular dilatation in preterm newborns and neurodevelopment.

Background: We investigated the temporal evolution of post-hemorrhagic ventricular dilatation (PHVD) and compared neurodevelopmental impairments (NDI) in newborns with (Group 1) spontaneous resolution of PHVD, (Group 2) persistent PHVD without neurosurgical intervention, and (Group 3) progressive PHVD receiving neurosurgical intervention.

Methods: A multicenter retrospective cohort study of newborns born at ≤34 weeks with PHVD (ventricular index [VI] >97th centile for gestational age and anterior horn width [AHW] >6 mm) from 2012 to 2020. Severe NDI was defined as global developmental delay or cerebral palsy GMFCS III-V at 18 months.

Results: Of 88 survivors with PHVD, 39% had a spontaneous resolution, 17% had persistent PHVD without intervention, and 44% had progressive PHVD receiving intervention. The median time between PHVD diagnosis and spontaneous resolution was 14.0 days (IQR 6.8-32.3) and between PHVD diagnosis and first neurosurgical intervention was 12.0 days (IQR 7.0-22.0). Group 1 had smaller median maximal VI (1.8, 3.4, 11.1 mm above p97; p < 0.001) and AHW (7.2, 10.8, 20.3 mm; p < 0.001) than Groups 2 and 3. Neurodevelopmental outcome data were available for 82% of survivors. Group 1 had reduced severe NDI compared to Group 3 (15% vs 66%; p < 0.001).

Conclusion: Newborns with PHVD without spontaneous resolution are at higher risk for impairments despite neurosurgical interventions, which may be due to larger ventricular dilatation.

Impact: The natural evolution of post-hemorrhagic ventricular dilatation (PHVD) and developmental implications of spontaneous resolution are not well established. In this study, approximately one in three newborns with PHVD experienced spontaneous resolution and this subset of newborns had reduced rates of neurodevelopmental impairments. More prominent ventricular dilatation was associated with reduced rates of spontaneous resolution and increased rates of severe neurodevelopmental impairment among newborns with PHVD. Understanding clinically relevant time points in the evolution of PHVD and predictors of spontaneous resolution may help inform the discussion around the optimal timing for intervention and allow for more precise prognostication in this population.