[en] Introduction: There are a number of pulmonary diseases during infancy that predispose to chronic respiratory conditions at the adults age. Bronchiectasis, malformations, bronchogenic cysts, atelectasis and sequels of adenovirus infection are frequent factors for recurrent respiratory diseases, that can produce a permanent pulmonary damage. The pulmonary radioisotopic studies allow a reliable pre-operatory evaluation in order to determinate the global and segmental pulmonary function. Chronic hypoventilated territories shown secondary hypoperfusion, giving as a result a match defect in the ventilation/perfusion scintigraphy. Goal: To determinate if the perfusion scintigram alone is enough in order to evaluate the pulmonary function in pediatric population with chronic pulmonary diseases. Materials and Methods: All ventilation/perfusion scintigraphic studies done in children with chronic pulmonary diseases derived to our center between 1999-2001 were analyzed. A total of 58 children (25 boys and 33 girls, in a age range from 1 month to 17 years) were studied. The most frequent indications the study were: bronchiectasis, pulmonary hypoplasia, several bronchitis and sequels of adenovirus respiratory infection. This last one represents the 31% of all cases. The number and location of each perfusion and ventilation defects where correlated. Results: Twelve out of the 58 children had normal lung scintigraphics studies (21%), 44 showed mixed defects (76%), in 1 child only one perfusion defect was found (1.5%) and in other child only a single ventilation alteration was seen (1.5%). Conclusion: According to the results in our group, we observed that in chronic pulmonary diseases most cases have matched ventilation/perfusion defects, because of readecuation of the pulmonary blood flow. The perfusions scintigraph was diagnosed in 98.5% of the studied cases. This allows us to suggests that in the evaluation of pulmonary damage in children with chronic pulmonary diseases, the perfusion scintigraphy is an accurate procedure for the evaluation of the pulmonary function