[The wall in persistent ductus arteriosus (author's transl)].

A light microscopy study of the wall in ductus arteriosus was performed in 13 cases of isolated persistent ductus. The specimens were obtained surgically in 11 cases and by necropsy in 2. Four patients were male, 9 female. The eldest was a 9-year-old girl and the youngest, a 4-month-old girl. Morphologically, a progressive transformation of the duct wall to the elastic-type artery was observed. In this transformation three stages were determined; stage I: laminar elastosis of the intima; stage II: same as stage I plus incomplete elastic transformation of the media; and stage III: fully developed elastic-type artery. A neat correlation between morphologic stages and clinical data was not found. The course of events in this transformation is apparently determined in great measure by individual factors.