Prenatal prediction of respiratory distress syndrome by multimodality approach using 3D lung ultrasound, lung-to-liver intensity ratio tissue histogram and pulmonary artery Doppler assessment of fetal lung maturity

Studying the correlation of different lung parameters, using three-dimensional ultrasound (3D US) with fetal lung maturity (FLM) to predict the development of neonatal respiratory distress syndrome (RDS).Three-dimensional ultrasound was done to record the fetal lung volume (FLV), fetal lung-to-liver intensity ratio (FLLIR) and the main pulmonary artery (MPA) blood flow parameters; pulsatility index (PI), resistive index (RI) and acceleration time-to-ejection time ratio (At/Et), to 218 women between 32 and 40 weeks gestational age within 24 h from labor.Of 218 fetuses examined, final analysis was done for 143 fetuses. Thirty eight (26.5%) were diagnosed with RDS. The MPA PI and RI were significantly higher in fetuses diagnosed with RDS compared with those without (2.51 ± 0.33 and 0.90 ± 0.03 cm/s versus 1.96 ± 0.20 and 0.84 ± 0.01 cm/s; p value < 0.001 and <0.001 respectively). MPA At/Et was significantly lower (0.24 ± 0.04 vs 0.35 ± 0.04; p value < 0.001). FLLIR was significantly lower (1.04 ± 0.07 vs 1.18 ± 0.11; p value < 0.001), and the mean FLV was significantly smaller (28.23 ± 5.63, vs 38.87 ± 4.68 cm3; p value < 0.001).Main pulmonary artery (PI, RI, At/Et ratio), FLIIR, and mean FLV can be used as reliable predictors of neonatal RDS.3D ultrasound VOCAL technique, ultrasound tissue histogram and pulmonary artery Doppler are reliable tools for prenatal prediction of fetal lung maturity.