How is fetal pulmonary hypoplasia assessed on Ultrasound?
The appearance of a small fetal thorax and low thoracic circumference is suggestive of pulmonary hypoplasia.
A fetal thorax-to-head ratio of <1 carries a poor prognosis. The echogenicity of the fetal lungs on US is not a reliable indicator of lung maturity.
Pulmonary hypoplasia can be idiopathic or secondary (from oligohydramnios or from mass effect by an intrathoracic mass such as a congenital diaphragmatic hernia (CDH) or congenital cystic adenoid malformation (CCAM) of the lung).
