For early-stage proximal gastric cancer, proximal gastrectomy (PG) preserves gastric function but often causes severe gastroesophageal reflux that impairs quality of life. Because reconstruction geometry reshapes intragastric flow near the esophagogastric junction (EGJ), we aim to identify the key geometric-biomechanical factors in esophagogastric anastomosis that affect reflux. We conducted a clinical–computational fluid dynamics (CFD)–clinical closed-loop study to evaluate postoperative anti-reflux performance after PG. A retrospective analysis of 59 patients who received PG compared anti-reflux outcomes across standard reconstructions, enabling the identification of five procedural differences for CFD modeling. Using four patient-specific CFD models, single-variable analyses of five geometric features were conducted following virtual PG to quantify intragastric flow changes across geometries, with results compared to clinical data. The double-flap technique demonstrated an 84.2% reflux control rate, superior to other reconstructions (P = 0.001) and consistent with CFD-identified low-reflux geometry. CFD simulations confirmed that a lesser curvature site anastomosis, small anastomosis diameter, and cranial anastomosis angulation each independently reduced reflux (P 0.05). Crucially, this study established a novel three-dimensional transient quantitative analysis for reflux, enabling direct comparison of reflux volume across geometries. Beyond total reflux, the EGJ vortex volume fraction and pressure recovery characteristics provided reliable flow-field metrics to distinguish reflux risk. Validation with non-Newtonian puree showed consistent performance of the low-reflux geometry across fluid types. Thus, we translate the success of the empirically optimal technique into a quantifiable and interpretable geometric-fluid dynamic standard, offering a validated and robust configuration for anti-reflux reconstruction after PG.
Wang et al. (Sun,) studied this question.