OP38.05: Prognostic value of first trimester nuchal translucency in isolated congenital diaphragmatic hernia

Abstract

To investigate the prognostic value of increased nuchal translucency (NT) thickness in the first trimester in fetuses with isolated congenital diaphragmatic hernia (CDH). We conducted a retrospective study of all consecutives cases of CDH referred to our unit for prenatal care between January 2004 and June 2010. NT was measured at between 11 and 13 + 6 weeks during first trimester routine scan therefore blinded to the subsequent diagnosis and outcome. Cases with termination of pregnancy or associated genetic, chromosomal or anatomical anomalies were discarded. We investigated the prognostic value of enlarged NT as well as the correlation between NT (MoM) and liver location, side of CDH, lung-to-head ratio (LHR), LHR observed/expected (O/E), lung volume estimated by MRI. Perinatal outcome was defined as survival at discharge from the NICU. 83 cases were reviewed. Enlarged NT, defined as > 95th percentile occurred in 9/83 (11%) cases. Neonatal death occurred in 7/9 (78%) cases with increased nuchal translucency, compared with 35/74 (47%) cases with normal translucency. No significant correlations were found between the value of NT (MoM) and the LHR, LHR O/E, lung volume estimated by MRI. The median NT was 1 MoM and 0.9 MoM for right-sided and left-sided CDH respectively (P = 0.17). Median NT was 1 MoM and 0.86 MoM for liver-up and liver-down cases respectively (P = 0.05) Nuchal translucency may be a prognostic factor for CDH. Furthermore, the prognostic value of enlarged first trimester NT may be unrelated to other markers of lung compression except liver location.