Abstract
A 30-year-old woman was admitted complaining of right chest pain during menses. Chest radiograph revealed pneumothorax, leading to the suspicion of catamenial pneumothorax because pulmonary bullae could not be confirmed using chest computed tomography. However, during the following 7 months, pneumothorax recurred four times during menstruation, leading to video-assisted thoracic surgery for further diagnosis. Several fistulas were found in the central tendon of the diaphragm, along with bloody pleural effusion; there were no remarkable changes in the visceral pleura. The diaphragm was partially resected, including all fistulas. After surgery, we observed a blueberry spot on the abdominal side of the diaphragm that could not be observed using a thoracic approach. This spot was confirmed to be endometrial tissue on the abdominal side of the diaphragm. The patient did not receive post-surgical hormone therapy; pneumothorax recurred 9 months postoperatively. Surgical treatment, via a thoracic approach, could not detect an abdominal cavity lesion, which is a reason why catamenial pneumothorax often recurs after surgery.
