[A case of round atelectasis related to spontaneous pneumothorax in a patient with neurilemmomatosis].

A 60-year-old man was admitted to our department for investigation of abnormal shadows on his chest X-ray. He had been diagnosed as having neurilemmomatosis in 1987. His chest X-ray showed nodular shadows in left S5 and S8 and localized spontaneous pneumothorax in left lung field. The nodular shadows, which were in contact with thickening of the pleura, showed curved shadows of bronchi and vessels (so-called comet tail sign). We suspected that they were round atelectasis, but to confirm the diagnosis and to treat the pneumothorax, limited resection of the lung and resection of the bulla were performed. The diagnosis of round atelectasis was confirmed by histological findings. Round atelectasis related to spontaneous pneumothorax is a very rare condition; however, we consider this to be an important case for understanding the pathogenesis of round atelectasis.