['We hypothesized that patients who have previously had bariatric surgery and are undergoing revision to laparoscopic Roux-en-Y gastric bypass would have abnormal findings detected by upper endoscopy that could potentially influence patient management. The procedures that are being revised include vertical banded gastroplasty, laparoscopic adjustable gastric bands, nonadjustable gastric bands and previous Roux-en-Y gastric bypass (open and laparoscopic).', 'We conducted a retrospective chart review of patients who previously had undergone vertical banded gastroplasty or nonadjustable gastric banding. We preoperatively performed an upper endoscopy on all patients. The endoscopy reports were reviewed and the findings entered into a database.', 'Eighty-five percent of 46 patients undergoing revisional bariatric surgery had an abnormal upper endoscopy. Eleven percent had a gastrogastric fistula. Gastritis and esophagitis were noted in 65% and 37%, respectively. Eleven percent of patients had band erosion, 2 from a nonadjustable band, and 5 from vertical banded gastroplasties. Based on our findings, 65% of our patients required medical treatment.'] Is preoperative upper endoscopy useful before revisional bariatric surgery?