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Updated: Feb 3, 2026

Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Efficiency and risks of laparoscopic conversion of omega anastomosis gastric bypass to Roux-en-Y gastric bypass
Roel Bolckmans1, Gustavo Arman2, Jacques Himpens2
1Department of Bariatric Surgery, AZ Sint-Blasius, Dendermonde, Belgium. roel_bolckmans@hotmail.com.
Background:
There is a paucity on literature data related to conversion of Omega anastomosis gastric bypass (OAGB) to Roux-en-Y gastric bypass (RYGB).
Methods:
This is a retrospective study. Records of all patients who underwent this conversion were analyzed. Additionally, patients were contacted to answer a questionnaire on their current clinical condition.
Results:
Twenty-eight patients underwent laparoscopic conversion between September 2007 and June 2016. Indications were peritonitis in 7 patients (leaks after OAGB in 5, perforated marginal ulcer (MU) and blow-out remnant with concomitant leak in one patient each), anastomotic bleeding in one, bile reflux in 6, recalcitrant MU in 4, afferent loop syndrome in 6, postprandial vomiting in 2 (related to anastomotic stenosis and perianastomotic diverticulum, one each), and malnutrition and hypoglycemia both in 1. Thirty-day mortality was zero, complication rate (Clavien-Dindo grade III or more) 5% ((N = 1/20), abscess) when conversion was elective and 50.0% ((N = 4/8), all persisting leaks) when conversion was urgent. All 4 leaks persisting after conversion were successfully treated by endoscopic stenting, despite stent migration in 2 patients. Follow-up was available in 92.9%, for a mean time of 64.5 ± 30.1 months. Successful symptom relief (Likert score 4 or more) was noted for bile reflux and postprandial vomiting. Additionally, malnutrition was corrected.
Conclusions:
When indicated, conversion of OAGB to RYGB is a safe treatment strategy. In case conversion is performed for leak after OAGB, persisting subclinical leaks are frequent but can be efficiently addressed by endoscopic stenting.
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