Failure of gastroplasty pouch and stoma size to correlate with postoperative weight loss.

At the University of Alberta hospitals patients who underwent gastroplasty--horizontal, vertical with multistranded nylon banding of the stomas and vertical banded with Teflon reinforced stomas--have been followed up for over 2 years. Pouch volume ranged from 25 to 30 mL. Pouch volume and stoma size were measured radiologically 2 years after operation and correlated with the percentage excess weight loss. Any patient failing to lose at least 40% of the excess weight was considered a failure. There was no consistent correlation between pouch or stoma size and percentage excess weight loss for any of the three procedures studied. The failure rate for patients included in the study group was 33.3% for horizontal, 32.4% for vertical and 32.8% for vertical banded gastroplasty. The probable reason for the lack of correlation is that some patients change their diets so as to subvert the restriction imposed by the gastroplasty.