Prenatal assessment and prediction in CDH: for what purpose?

Congenital diaphragmatic hernia is most often diagnosed prenatally, and accurate assessment is crucial for prognosis parental counselling and therapeutic planning. The assessment of pulmonary hypoplasia is currently the most relevant prognostic indicator. Ultrasound and MRI parameters such as the observed-to-expected lung-to-head ratio and total fetal lung volume serve as the primary predictors of neonatal outcome. However, these markers are not predictive of associated complications like persistent pulmonary hypertension of neonates and cardiac dysfunction, which also significantly influence survival and morbidity. Although new imaging parameters have been proposed, their clinical utility is limited by insufficient validation and inter-center variability. This review critically evaluates current prenatal imaging methods for congenital diaphragmatic hernia, highlighting their strengths and limitations. A better understanding of the underlying pathophysiology, alongside efforts to develop standardized, reproducible and eventually predictive markers, is essential to refine prognosis, optimize fetal therapy selection, eventually improving outcomes for affected neonates.