Prenatal MRI abdominal volumetrics and outcomes after early surgery or paint-and-wait for giant omphalocele.

Giant Omphalocele (GO) poses significant challenges in neonatal management. Standard treatment is paint-and-wait with delayed fascial closure at 1-2 years-of-age. Alternatively, early surgery entails neonatal sac removal with either primary fascial closure or staged GORE-TEX patch-assisted closure. We compared outcomes between early surgery and paint-and-wait and evaluated whether prenatal MRI volumetrics can identify candidates for primary closure. We performed a retrospective study (2007-2024) of newborns with GO (sac diameter ≥5 cm with liver). For early surgery patients, prenatal MRI volumetric analysis measured intra-abdominal (IAV) and eviscerated organ volumes (EOV) to generate a novel evisceration index (Evisceration Index = (EOV/(EOV + IAV)) × 100. Forty-three infants met inclusion (25 early, 18 paint-and-wait). Groups were similar for birth <34 weeks, weight, sac diameter, and associated anomalies. No patients required ECMO. Mortality was comparable (8.0% vs. 11.1%; p = 1.00). Early surgery achieved earlier fascial closure (27 vs. 464 days; p < 0.01) with 34.8% closed at the first operation. Tracheostomy was less common with early surgery (4.0% vs. 33.3%; p = 0.02). Among early surgery infants with prenatal MRI (n = 21), those achieving primary closure had a lower evisceration index (16.0% vs. 37.0%; p < 0.01). ROC analysis identified an evisceration index cut point of 26%, above which staged closure was necessary. Early surgery results in earlier fascial closure with lower tracheostomy rates. Prenatal MRI volumetric analysis demonstrated potential utility for identifying GO patients who may be able to undergo primary fascial closure with a single operation supporting the possibility of a more individualized approach to prenatal counseling.