Phlegmon Formation due to Perforated Marginal Ulcer After One Anastomosis Gastric Bypass; Conversion to Roux-en-Y Gastric Bypass: a Video Case Report.

One anastomosis gastric bypass is now an accepted bariatric procedure in many countries. A rare but serious complication of OAGB is perforation of marginal ulcer with 0.5-1% incidence that needs urgent diagnosis and intervention. In cases of complicated or refractory ulcers, conversion to RYGB could be a definitive therapy.