The pulmonary ventilation scintigraphy with 99m Tc diethylene-triamine-pentaacetate (99mTc-DTPA) delivered through a new nebulizer system when analyzed together with the classic lung perfusion scintigraphy with 99mTc-labeled albumin macroaggregates (99mTcMAA) is a very important diagnostic tool in several pulmonary diseases. Several aspects of the lung ventilation-perfusion scintigraphy are studied in 15 people with no lung disease, smokers and nonsmokers. The findings with the lung ventilation-perfusion scintigraphy are also discussed in 34 patients with several pulmonary diseases: lung cancer, chronic obstructive lung disease, policystic pulmonary disease, and pulmonary embolims. The authors concluded that the procedure is a valuable diagnostic tool in several pulmonary diseases, especially because good lung images are obtained, no side effects were detected, the technique is ease and low cost, and it brings new informations, not available with other diagnostic methods. (author).