Composite Scoring and the Natural Course of Post-Hemorrhagic Ventricular Dilation in Neonates with Severe Intraventricular Hemorrhage

Background Post-hemorrhagic ventricular dilation (PHVD) is a significant complication in 30–50% of severe intraventricular hemorrhage (SIVH), yet the temporal dynamics of ventricular expansion and late “recoil” remain incompletely characterized. Objective To quantify the rate, magnitude, and temporal pattern of ventricular expansion following SIVH using serial cranial ultrasound measurements, and to explore associations with hemorrhage burden and mortality. Design/Setting Retrospective cohort study of neonates cared for at University Hospital Neonatal Intensive Care Unit (NICU) in Newark, NJ (01/2010–01/2025). Participants 43 neonates with SIVH and PHVD were included. Mortality was 37.2% (16/43); 11.6% (5/43) underwent invasive intervention. Methods Ventricular dilation was quantified on serial head ultrasounds using ventricular index (VI) and anterior horn width (AHW); 347 cranial ultrasounds were analyzed (8 per patient). Growth trajectories were modeled primarily as a function of postmenstrual age (PMA). Results Across the cohort, both VI and AHW increased significantly with PMA, with mean expansion rates of 0.105 mm/day for VI (95% CI 0.092–0.118) and 0.105 mm/day for AHW (95% CI 0.087–0.124) (both p < 0.001). Highest IVH grade (3 vs 4) did not significantly modify growth rate, but a composite bilateral hemorrhage-burden score better stratified outcomes and growth dynamics. When the composite score was grouped into low (3–6) vs high (7–8), high-burden infants demonstrated faster expansion (VI 0.126 vs 0.096 mm/day, p = 0.025; AHW 0.139 vs 0.091 mm/day, p = 0.013). Over time, VI expansion was effectively monotonic, while AHW showed only minor late recoil; overall, late ventricular shrinkage was uncommon. Mortality in the high composite group was 4.79 times higher than the low composite group (p = 0.024). Each 1-point increase in composite IVH severity showed a clinically meaningful association with mortality (OR 1.51 per 1-point increase; p = 0.072) and differed significantly between survivors and non-survivors (Wilcoxon p = 0.034). Conclusions In this retrospective NICU cohort with SIVH-associated PHVD, ventricles enlarged at an approximately linear rate over PMA, with faster expansion in infants with higher composite hemorrhage burden. Composite score was a better predictor of dilation size and mortality. Ventricular “recoil” was minimal, supporting that ventricular size often remains near peak dimensions over the observed course.