The validity of the viscero-abdominal disproportion ratio for type of surgical closure in all fetuses with an omphalocele

Objective To determine the predictive value of the fetal omphalocele circumference/abdominal circumference (OC/AC) ratio for type of surgical closure and survival and to describe the trajectory of OC/AC ratio throughout gestation. Methods This cohort study included all live‐born infants prenatally diagnosed with an omphalocele in our tertiary centre (2000–2017) with an intention to treat. The OC/AC ratio and liver position were determined using 2D ultrasound at three periods during gestation (11–16, 17–26, and/or 30–38 weeks). Primary outcome was type of closure; secondary outcome was survival. In the secondary analyses, the predictive value of the OC/AC‐ratio trend for type of closure and survival was assessed. Results Primary closure was performed in 37/63 (59%) infants, and 54/63 (86%) survived. The OC/AC ratio was predictive for type of closure and survival in all periods. Optimal cut‐off values for predicting closure decreased throughout gestation from 0.69 (11–16 weeks) to 0.63 (30–38 weeks). Repeated OC/AC‐ratio measurements were available in 33 (73%) fetuses. The trend of the OC/AC ratio throughout gestation was not significantly associated with type of closure. All infants without liver herniation underwent primary closure. Conclusion Type of omphalocele surgical closure and survival can be predicted prenatally on the basis of the OC/AC ratio and liver herniation independent of associated anomalies. Learning objective The reader will be able to use the OC/AC ratio throughout gestation in all omphalocele cases for prediction of type of closure and survival and thus patient counselling.
What's already known about this topic? In fetuses with an isolated omphalocele, the OC/AC ratio is less than 24 weeks; gestation is of predictive value for postnatal type of closure. What does this study add? The OC/AC ratio is predictive for type of surgical closure and survival in all fetuses with an omphalocele.This report is the first concerning the trend of the OC/AC ratio throughout gestation.The OC/AC ratio best predicts type of closure and survival in the third trimester of pregnancy.