Can three-dimensional ultrasound be used for the assessment of the fetal lung volume in cases of congenital diaphragmatic hernia?

We report on 2 fetuses with congenital diaphragmatic hernia (CDH) in whom the fetal lung volumes were estimated by three-dimensional ultrasound and the results compared with the postmortem lung volume measurements. Both examiners (sonographer and pathologist) were blinded to each other's results. The 1st case was a right CDH diagnosed at 20 weeks of gestation. The 2nd case was a left CDH diagnosed at 22 weeks of gestation. Both pregnancies were terminated upon request of the parents. Three-dimensional ultrasound estimation of the fetal lung volume was performed 1 day before termination of pregnancy using the technique of rotation of the three perpendicular planes. The left and right lung volumes estimated by three-dimensional ultrasound were 3.88 and 1.87 cm³, respectively, in the 1st case and 0 and 5.52 cm³, respectively, in the 2nd case. On postmortem examination, the left and right lung volumes were 3.0 and 2.2 cm³, respectively, in case 1 and 1.1 and 5.6 cm³, respectively, in case 2. This suggests that a three-dimensional estimation of pulmonary volumes may be correlated with postmortem findings in cases with CDH.