Fetal MRI-calculated total lung volumes in the prediction of short-term outcome in giant omphalocele: preliminary findings.

OBJECTIVE: To determine the value of fetal MRI-calculated total lung volumes (TLV) in the prediction of short-term outcome in patients with giant omphalocele (GO).

MATERIAL AND METHODS: We reviewed all cases of GO undergoing fetal MRI after 21 weeks' gestation and receiving postnatal care at our institution between 2003 and 2010. Observed/expected (O/E) TLV was calculated using age-matched TLV normograms [Radiology 2001;219:236-241]. Postnatal outcomes were stratified based on O/E TLV above or below 50% of expected.

RESULTS: Seventeen GO cases fulfilled the entry criteria. The mean age at fetal MRI evaluation was 25.8 ± 4.8 weeks' gestation. The mean GO TLV (21.0 ± 13.2) was lower than age-matched population norms (p < 0.001), resulting in a mean O/E TLV of 52.3 ± 16.8%. The mean gestational age at delivery was 36.8 ± 1.6 weeks. Overall survival was 94%. Fourteen (88%) infants underwent staged reduction, and 2 underwent silver sulfadiazine treatment and delayed repair. Infants with ≤50% of predicted O/E TLV (n = 11, 65%) had lower Apgar scores at birth (p = 0.03), prolonged ventilatory support (p = 0.004), delayed oral intake (p = 0.03), and longer hospitalization (p = 0.03) compared to patients with ≥50% of expected O/E TLV. Two infants (both O/E TLV <50%) required tracheostomy placement.

CONCLUSION: In the assessment of GO fetuses, MRI-based O/E TLV of <50% was predictive of increased postnatal morbidity.