Relation of Gastric Volume With Weight Loss After Sleeve Gastrectomy: Results of a Prospective Analysis

Background: Postoperative sleeve volume (SV) is a key factor in evaluating the results of laparoscopic sleeve gastrectomy (LSG). An objective measurement of SV was obtained with 3-dimensional computed tomographic (3DCT) reconstruction. Several studies have compared SV with percent excess weight loss (%EWL), identifying an inverse relationship. We hypothesized that gastric capacity is one of the factors responsible for weight loss after LSG. Objectives: Outcomes of the study were the analysis of the inverse correlation between SV and weight loss (%EWL and body mass index) at the 12-month follow-up, and evaluation of SV in the group with %EWL >50%. In addition, the failure rate was quantified in the SV >180 mL group. Materials and methods: This is a prospective study with the collection of data. All patients who received LSG from January to December 2017 were evaluated. Computed tomography was performed on the upper abdomen at 12 months postoperatively to measure the SV using a standardized technique involving gastric distension. Results: A total of 42 patients were considered for 3DCT evaluation at the 12-month follow-up. A significant linear inverse relation was reported between SV and %EWL (P<0.05); a similar trend, without significant results, was reported for body mass index loss. The entire cohort was subdivided according to %EWL. A %EWL<50% presented a significantly higher mean SV (P<0.01) than %EWL >50%. SV >180 mL was powerful in predicting abnormal gastric distension. Over this value, %EWL was lower than that in the remaining group (P<0.05, 31.9% vs. 51.8%). Conclusions: Our results confirmed a direct relation between SV and %EWL. Objective evaluation of gastric compliance obtained with 3DCT should be used intensively for LSG.