Purpose or Case Report: Frequently diagnosed on prenatal imaging, including fetal MRI, omphalocele has highly variable morbidity and mortality. Few prenatal prognostic indicators have been previously identified. We propose that features found on fetal MRI can predict morbidity and mortality in patients diagnosed with omphalocele.
Methods & Materials: We performed a retrospective review of all patients prenatally diagnosed with omphalocele who received fetal MRI from 2006-2017 at a single institution. Thirty neonates met study criteria. Imaging biomarkers identified on fetal MR included observed-to-expected total fetal lung volume (O/E TFLV); herniation of stomach, spleen, or liver; omphalocele size; and number of umbilical cord vessels. The primary outcome was survival, whether to birth or to discharge. Bivariate and multivariable regression analyses were performed.
Results: Seventy percent of patients survived to birth, and 45.2% survived to discharge. On bivariate analysis, observed/expected total fetal lung volume (O/E TFLV) correlated with survival to discharge (69 ± 29% vs 39 ± 25% for survivors vs. non-survivors, respectively (p = 0.007)). 23.1% of patients with stomach herniation (p = 0.021) and no patients with a herniated spleen survived to discharge (p<0.001). Liver herniation on MRI approached, but did not reach, significance for survival to discharge (53% vs. 81% for survivors vs. non-survivors, respectively (p=0.06)).
On multivariable regression analysis after controlling for gestational age and gender, stomach herniation on MRI predicted lower likelihood of surviving at discharge (Adjusted Odds Ratio: 0.04 [CI: 0.004, 0.557], p=0.016).
Conclusions: Utilizing one of the largest reported series, this advanced imaging series of omphalocele demonstrates the value of organ-specific characterization to prognostication. While identifying liver position has long been recognized as valuable in predicting outcome, our analysis found predictive value for spleen and stomach position as well. These markers should be examined in a larger patient cohort with the goal of creating a validated set of prognostic imaging biomarkers.