Surgical lung volume reduction is a method for treatment of advanced pulmonary emphysema after all other therapeutic approaches have failed. 280 atypical lung resection specimen of 81 patients were examined pathologico-anatomically using routine stains. In all cases combinations of various forms of emphysema were found; in 65.8% there were also bullous changes (with > or = 1 cm diameter) focally. Acute bronchiolitis was seen in 41.8% of the specimens, an only slight (if at all) chronic bronchiolitis in 26.7% and bronchioloectasia in 45.4% of the cases. Focal intraalveolar aggregates of granulocytes were identified in 16.1%, and the process of permanent scarring resulting in "organised pneumonia" in 20.6% of the specimens. Occult neoplasms were found in 9.9% of the patients and specific changes in 27.2%. Bronchiolitis is relevant for postoperative prognosis and an indication for intensifying antibiotical and antiinflammatory therapy. Preoperative diagnostical procedures should be intensified to find out these patients. Inflammatory changes must be investigated in respect of etiology and pathogenesis.