Prenatal treatment of type I congenital cystic adenomatoid malformation by intrauterine fetal thoracentesis.

Congenital cystic adenomatoid malformation of the lung is a developmental abnormality characterized by abnormal proliferation of terminal bronchioles forming cysts of varying sizes. Extensive lesions are associated with a poor prognosis due to the development of nonimmune hydrops and/or pulmonary hypoplasia. The advent of high-resolution ultrasonography has made it possible to identify these lesions during the antenatal period. With the prenatal identification of cystic adenomatoid malformations comes the potential for in utero intervention to modify the natural history of this process and prevent the development of hydrops and pulmonary hypoplasia. An instance of successful intrauterine treatment of congenital cystic adenomatoid malformation is presented.