Figure: No Caption available.Purpose: We report a successful ampullectomy of a partially prolapsing intraductal ampullary adenoma using an improvised endoscopic technique of attaching an adjunctive tube to allow simultaneous passage of a balloon catheter and snare. Methods: A 78-year-old woman with a history of hypothyroidism was involved in a motor vehicle collision and underwent a CT scan that, incidentally, revealed a 17 x 20-mm ampullary mass. On ERCP, the ampulla bulged with a soft polypoid tissue mass. FNA showed benign glandular cells. Respecting the patient's wish to avoid Whipple procedure, we offered an endoscopic approach. The ERCP was performed in the operating room with the patient supine and surgeons on standby for a Whipple surgery. Intraductal tumor extension in the periampullary area was endoscopically seen. The ampulla was cannulated and sphincterotomy was performed, taking the cut as high as possible. Segmental resection around the ampulla edges using the hot snare removed the intraduodenal part of the mass. A sterile hollow accessory tube was then attached to the endoscope. A snare was passed through the endoscope and a balloon catheter through the accessory tube. The snare was looped around the balloon. The balloon catheter tip was manipulated with the snare to cannulate the bile duct, passed over a wire to above the lesion, and then retracted, completely prolapsing the tumor. The looped snare was advanced over the balloon catheter and the entire prolapsed ampullary adenoma, completely resecting it. The resection site was impressive for deep tissue exposure to the level of the muscle fibers with ductal mucosa widely separated from the duodenal mucosa. Pancreatic and bile duct stents were placed. Duodenocholedochal clipping was done around the stents, mimicking anastomosis. With no post-procedural complications, she was discharged home after a 24-hour observation period. A threemonth follow-up ERCP showed patent ducts and resolution of the previously-observed filling defect from the adenoma intraductal extension. EGD at six months revealed no residual adenomatous growth. Conclusion: The only definitive therapy for intraductal ampullary adenoma is complete excision, but they are suboptimal candidates for standard ampullectomy. A custom-added accessory channel allowed successful utilization of two devices to completely excise an intraductal ampullar adenoma without surgical intervention.