[Light and scanning electron microscopy studies of the pleura. A contribution to the pathogenesis of spontaneous pneumothorax in young patients].

In a prospective study of 10 patients (7 men, 3 women, mean age 26.2 years), who underwent thoracotomy because of recurrent spontaneous pneumothorax, we performed light and scanning electron microscopic investigations of the resected pleura. The purpose of our work was to explain pleural changes which allowed the penetration of air through the intact wall of the blebs. In 8 of 10 cases we found small bullae at the top of the upper lobe, the remaining 2 showed up with massive pleural scar. The morphological and ultrastructural findings indicated that the presence of air induced a reactive process at the visceral pleura which led to degeneration and scarification. The changes consisted of simple membrane formation up to complete destruction of the pleural layer. The development of blebs is due to an air fistula coming out of the lung parenchyma. Penetration of air through the bleb's wall is explained with the increasing pressure inside and the dehiscence of degenerated pleural structure. In our opinion spontaneous pneumothorax in young people is caused by a localized disease of the upper lobe. The pleural changes are the visible effects of a degenerative process induced by air fistula from lung parenchyma. Therefore wedge-resection of that region is a rational therapy in patients with spontaneous pneumothorax.