Iatrogenic diaphragmatic hernias have been reported as a rare complication of thoracic and abdominal surgery. We herein report a case of delayed iatrogenic left diaphragmatic hernia after diaphragm pedunculated lipoma resection with minimally invasive surgery.

A 72-year-old Japanese man was found to have an abnormal shadow by medical checkup X-ray and was admitted to our hospital. Chest computed tomography (CT) showed a 5 × 2-cm solid tumor at the left diaphragm. He was diagnosed with a left diaphragm tumor. We performed three-port video-assisted thoracic surgery. This tumor was pedunculated at the left central tendon of the diaphragm. We therefore dissected this tumor using an electric scalpel. Although there was about 5 × 4 mm in diameter slight heat damage to the diaphragm, it was not reinforced because it was very minor injury. He was diagnosed with a left diaphragmatic hernia without any symptoms by routine CT examination which scheduled 1 year after surgery. One day after hospitalization, on the morning of the operation, he suddenly complained of left back pain with acute exacerbation of the left diaphragmatic hernia. We therefore immediately performed emergency surgery and rescued this patient. No adverse events or complications were seen, and he was discharged on postoperative day 11. Three months after this surgery, this patient is doing very well.

Caution should be exercised when using energy devices on the diaphragmatic surface, especially the left side, to avoid causing delayed diaphragmatic hernia. In cases of surgery involving the left-side diaphragm, it seems that careful follow-up after surgery is necessary.