Four-dimensional ultrasonographic guidance of fetal tracheal occlusion in a congenital diaphragmatic hernia

Intermittent fetal tracheal occlusion is considered one actual therapeutic option for a severe isolated congenital diaphragmatic hernia (CDH). To reduce maternal risks such as maternal hemorrhage, premature rupture of membranes, and preterm labor, minimally invasive procedures with extremely thin endoscopes have been introduced. The thinnest cannula used up to now was 3.3 mm with an endoscope of 1.2 mm. This procedure is usually guided by conventional 2-dimensional ultrasonography (2DUS). Recently, 4-dimensional ultrasonography (4DUS) was used to guide invasive obstetric procedures such as amniocentesis, chorionic villus sampling, and cordocentesis, as well as cauterization of an umbilical cord in twin-twin transfusion syndrome. The advantage of 4DUS maybe related to the reduction of procedure time and the ability to use thinner endoscopes. We report another possible contribution of 4DUS in the guidance of introduction of a thinner fetoscope (1.0 mm) into the fetal oral cavity.