Impact of 3D-CT-Based Gastric Wall Volume on Weight Loss after Laparoscopic Sleeve Gastrectomy

Purpose There are several debates on the association between gastric anatomy and weight loss after laparoscopic sleeve gastrectomy (LSG). There is a paucity of data on the impact of gastric wall volume (GWV) on weight loss. This study therefore aimed to investigate the effect of GWV on weight loss response after LSG. Materials and Methods Thirty-two patients with body mass index (BMI) of ≧ 40 kg/m 2 who underwent LSG between November 2016 and August 2018 were enrolled. Three-dimensional computed tomography (3D-CT) was performed pre-operatively and 1 year after LSG to assess gastric volumes. The population was divided into two groups: the first 20% ( n = 7) with the largest GWV, defined as LGWV group, and the rest of the population ( n = 25), defined as the small GWV (SGWV) group. Percentage total weight loss (%TWL) was compared. Results The mean preoperative GWV was 216.9 ± 47.7 ml in the SGWV group, versus 336.3 ± 24.1 ml in the LGWV group. Patients with LGWV had significantly lower 1-year %TWL (34.9.1% versus 27.9%, p = 0.0439). Multilinear regression identified LGWV as a significant prognostic factor after adjusting for BMI and early weight loss response. Repeated measure mixed effect model showed that the LGWV group had a significantly slower %TWL change, particularly after 3 months postoperatively. No association was found between 1-year %TWL and preoperative and postoperative gastric luminal volume or resected gastric volume. Conclusion 3D-CT disclosed GWV, but not other gastric anatomical characteristics, was an independent predictor of %TWL after 1-year post LSG.