Relevance of Roux-en-Y gastric bypass volumetry using 3-dimensional gastric computed tomography with gas to predict weight loss at 1 year.

Background: Causes of Roux-en-Y gastric bypass (RYGB) failures are still controversial. Literature data suggest that gastric pouch or gastrojejunal anastomosis distentions over time could be a key factor. Making the hypothesis that progressive distention of RYGB volumes is 1 of the main factors of weight loss failure, the aim of our study was to evaluate bypass volumes changes using repeated 3-dimensional gastric computed tomography with gas and the possible negative correlation with weight loss results at 1 year.

Methods: Thirty-nine patients eligible for RYGB were prospectively included. Gastric bypass volumes were assessed at 3 and 12 months postsurgery performing 3-dimensional gastric computed tomography with gas and weight loss outcomes were recorded during the first postoperative year.

Results: There was no loss to follow up. Mean % excess body mass index lost (%EBMIL) at 1 year was 66.7%. Seven patients (17.9%) did not reach Reinhold criteria and were considered as RYGB failures. We found no linear correlation between the 1 year %EBMIL and mean values of the gastric pouch (r=.01; P=.94), and the neo stomach (r=.09 ; P=.57) at 3 months. Revisional surgery was correlated negatively with %EBMIL at 1 year.

Conclusion: Weight loss at 1 year does not seem to be correlated to RYGB volume changes. Behavioral factors probably play a major role in weight loss failure.