Dropped Gallstones after Laparoscopic Cholecystectomy Leading to Intradiaphragmatic Abscess and Empyema. A Laparoscopic Approach to Gallstone Retrieval and Abscess Drainage A 79-year-old male with a history of hepatocellular carcinoma treated with Y-90 radioembolization presented in severe sepsis with right upper quadrant abdominal pain and fever nine months after laparoscopic subtotal cholecystectomy. CT scan demonstrated a right subphrenic abscess with calcified gallstones and right lower lobe consolidation with pleural effusion. Laparoscopic approach with patient in right lateral decubitus position was selected with easy access for right postero-lateral thoracotomy. The right liver was mobilized laparoscopically and a small hole in diaphragm was noted to be draining sanguineous, purulent fluid. Next, we entered the right chest via postero-lateral thoracotomy at 10^thintercostal space. By manual palpation of the intact pleural surface of diaphragm, we were able to remove gallstones and debride the abscess cavity intra-abdominally. We then performed decortication of the right lung. Microscopic examination demonstrated pigmented gallstones and chronic inflammatory giant cell reaction. OR cultures revealed Enterococcus Faecium and Enterobacter Aerogenes. Patient was discharged home on a two-week course of IV antibiotics. Most recent surveillance CT scan was performed 10 months postoperatively, and confirmed no abscess or pleural effusion. Dropped gallstones causing abscess can be difficult to treat. Percutaneous drainage does not remove the nidus of infection, so recurrent disease is likely. Laparoscopic drainage approaches should be considered, and further studies are needed to compare these modalities.