Congenital diaphragmatic hernia: Observed/expected lung-to-head ratio as a predictor of long-term morbidity

AimThe aim of this study was to investigate the association of observed/expected (O/E) lung-to-head ratio (LHR) with long-term morbidity for isolated fetal congenital diaphragmatic hernia (CDH) patients in a single institution.MethodsWe performed a retrospective study of prenatally diagnosed CDH from 18 to 38 weeks of gestation (01/2002-04/2010). Two cohorts of O/E LHR were defined (22.6-45%, 45.1-78.3%) based upon previous studies. Survivors with at least 1-year follow-up of prospectively collected long-term morbidity assessments were included.ResultsO/E LHR was available in 43 survivors (median 40%, range 22.8-78.3%). Follow-up data were available in 41 survivors (M:F = 24:17, left CDH = 39/41). Median follow-up was 6.5 years (1-11 years). Height/weight trajectories were similar between the two cohorts, with the majority below the 50th centile. There were no differences between the two cohorts by age 3 years for Bayley scales (developmental domains) and/or REEL-3 (language development). In addition, V/Q scans in the two cohorts demonstrated similar degrees of mismatch (mean delta V/Q = 35.4 versus 31.3).ConclusionsIn fetuses with isolated CDH, a reduction in O/E LHR does not predict a worse outcome in long-term follow-up. There is no association between a lower O/E LHR and a reduction in REEL-3 or Bayley score nor V/Q mismatch.