Fetal lung dysplasia: clinical outcome based on a new classification system.

OBJECTIVE: To evaluate the clinical application of a new classification system of fetal lung anomalies.
METHODS: Forty fetal diagnoses of lung lesions were analyzed according to our proposed classification system in which each lung component is considered using two-dimensional ultrasound and color and power Doppler technology. Medical files, natural history and neonatal follow-up were recorded.
RESULTS: Type I dysplasia: Four cases of agenesis of the lung were diagnosed, three with right lung agenesis and one with left lung agenesis. Three of the four patients elected to undergo termination of pregnancy (TOP). The surviving fetus was diagnosed with scimitar syndrome and postnatal embolization of the aberrant vessel was performed. Type II dysplasia: One case of normal lung with abnormal systemic feeding artery was diagnosed with normal neonatal outcome. Type III dysplasia: Abnormal lung with abnormal vascularity was found in 14 cases, presenting in most cases as echogenic lung masses. Seven were supradiaphragmatic, six subdiaphragmatic and one case was of undetermined position. All 14 fetuses showed an aberrant systemic artery emerging from the aorta. Abnormal venous drainage could be identified in only five (36%) of the fetuses: three had prominent azygos vein, one showed drainage to the inferior vena cava and one had multiple intrapulmonary veins forming a huge arteriovenous (A-V) shunt. Two cases in this group underwent TOP, the case with A-V shunt following development of hydrops, and one on maternal request. The remaining 12 fetuses (86%) survived and were alive and well at the time of writing; only one of them needed immediate postnatal embolization of the bilateral aberrant feeding arteries. Type IV dysplasia: Abnormal lung with no vascular abnormality was diagnosed in 20 fetuses. In this group there was one case of intrauterine fetal death, two patients underwent TOP, one complicated with hydrops and one on maternal request. The survival rate in this group was 85%. Only two cases needed immediate surgical repair. Type V miscellaneous dysplasia: One fetus demonstrated echogenic lung with split notochord syndrome and survived.
CONCLUSIONS: Congenital bronchopulmonary and related vascular anomalies can be categorized using the new classification system. This new approach enabled prenatal evaluation of each lung component and facilitated cogent management of the fetus with congenital lung dysplasia. Copyright 2004 ISUOG