Fetal pulmonary sequestration: a favorable congenital lung lesion

We reviewed the perinatal clinical course of prenatally diagnosed pulmonary sequestrations to determine the natural history of this anomaly.

From January 1992 to August 1998, 192 women were referred to the University of California, San Francisco, Fetal Treatment Center because obstetric ultrasound had demonstrated fetal lung lesions. In 14 fetuses, the echogenic lung masses were pulmonary sequestrations deriving arterial blood supply from clearly identifiable systemic arteries rather than the pulmonary artery. We examined records of the 14 fetuses and documented the location of the lesion, gestational age at diagnosis, need for fetal intervention, prenatal and postnatal complications, gestational age at delivery, and survival.

There were 16 intrathoracic pulmonary sequestrations in 14 fetuses (eight left-sided, four right-sided, two bilateral). Three fetuses had histologically mixed lesions (congenital cystic adenomatoid malformation and pulmonary sequestration). The mean age at diagnosis was 23 weeks' gestation (range 19-31 weeks). Two fetuses required prenatal intervention (placement of a thoracoamniotic shunt for drainage of an ipsilateral tension hydrothorax). The mean gestational age at delivery was 37 weeks (range 32-40 weeks). The large lesions of four fetuses regressed completely prior to birth, and the lesions of the remaining ten fetuses were electively resected after birth without causing morbidity or mortality.

Pulmonary sequestrations are a subgroup of congenital lung lesions with a favorable outlook; many regress prenatally, and the persistent ones are resected safely postnatally. Pulmonary sequestrations cause hydrops only because of a tension hydrothorax, which can be drained prenatally, if necessary.