Measurement of pouch volume and stoma diameter after gastroplasty.

A balloon technique has been developed for measurement of the pouch volume and stoma diameter after gastroplasty. Twenty-seven patients prospectively included in a randomized study of two types of gastroplasty operation have been investigated 6 months postoperatively. During the operation the proximal pouch was calibrated to be about 40 ml and the stoma diameter to 11 min. Six months after the operation the patients had on average reduced weight by 29 kg. Using the balloon technique, the stoma diameter was 12 +/- 1.6 (s.e.m.) mm and the pouch volume 80 +/- 11.0 ml. There was a significant correlation between the stoma diameter and weight reduction during the first 6 months postoperatively (P less than 0.01). The relationship between the stoma diameter and weight reduction followed best an exponential equation. No correlation was found between the pouch volume and weight reduction. The presented technique for measurement of pouch volume and stoma diameter after gastroplasty may be an important tool to evaluate the influence of various factors on the long-term results of surgical treatment for morbid obesity.