[Concept of defects in the interrupted development of the bronchopulmonary system. II. Dysplasias].

The dysplasias are defects in case of interrupted development to the respiratory section of broncho-pulmonary system with a relatively completed differentiation of the air passages. With the abortive development of pulmonary parenchyma, the bronchialization of the "primitive air spaces" is disturbed - the functional unity between pulmonary parenchyma and air passages is not realized. "The primitive air spaces" remain at an immature stage and are transformed into cyst-like formations. Dysplasias correspond to the so-called cystose lungs and its numerous synonyms. In our opinion, the term "dysplasia of the broncho-pulmonary system" in pathologoanatomical and pathogenetic sense more correctly reflects the discrepancy in organogenesis and histogenesis of the respiratory section of the air passages.