Low-dose cone-beam CT for gastric volumetry in endoscopic sleeve gastroplasty

The study aimed to evaluate the feasibility of using cone-beam computed tomography (CBCT) for gastric volume assessment before and after endoscopic sleeve gastroplasty (ESG), focusing on patient radiation dose. Ten patients scheduled for ESG were prospectively enrolled. Each patient underwent three CBCT scans under anesthesia: two scans following CO₂ insufflation of the gastric lumen-one pre-ESG and one post-ESG-and a third scan post-ESG after gastric distension with Gastrografin. Image quality was evaluated for its adequacy in generating three-dimensional reconstructions and calculating gastric volumes. Dose-area product was recorded for each scan and used to estimate the effective dose (ED) via Monte Carlo simulations using the PCXMC rotational model. Although image quality did not match conventional computed tomography (CT), it was sufficient for three-dimensional reconstruction and gastric volume measurements. The median ED was 4.2 mSv for pre-ESG scans with CO₂ insufflation, 4.2 mSv for post-ESG scans with CO2 insufflation, and 4.8 mSv for post-ESG scans with Gastrografin. CBCT provided satisfactory image quality for gastric volumetry at relatively low radiation doses, with ED being approximately 50% of that of conventional CT. This preliminary feasibility study suggests that CBCT could be a useful tool for planning ESG and assessing post-procedural outcomes. RELEVANCE STATEMENT: Low-dose CBCT provided sufficient image quality for gastric volumetry in a small cohort of patients undergoing ESG, reducing radiation exposure by approximately 50% compared to conventional CT. This investigational technique enables seamless intraoperative imaging that could improve planning and evaluation of endoscopic bariatric procedures. KEY POINTS: CBCT allowed gastric volumetric assessment at a relatively low radiation dose. Scans with CO₂ insufflation delivered lower radiation doses than scans with Gastrografin. Scans with CO₂ insufflation showed superior image quality compared to scans with Gastrografin. CBCT could be a valuable tool for planning ESG and evaluating outcomes.