Diagnostic utility of a CT upper gastrointestinal protocol for the detection of gastroduodenal leaks

PURPOSE: To evaluate the diagnostic performance of a novel CT upper gastrointestinal (UGI) protocol for detecting gastroduodenal leaks in patients who would typically undergo fluoroscopic UGI (fUGI). METHODS: In this retrospective cohort study, adult patients undergoing CT UGI between June 2022 and September 2025 were included. The protocol involved biphasic positive oral contrast administration 30 min and immediately prior to CT scanning in supine and right lateral decubitus positions. Study indication and CT findings were documented retrospectively; surgical findings and clinical follow-up served as reference standards. Sensitivity, specificity, PPV, and NPV were calculated. Mann-Whitney U tests compared length of stay (LOS) and imaging utilization by leak status. RESULTS: One hundred fifty-seven patients (184 exams; mean age 62.8 ± 13.8 years; 86 females) were included; 93% of exams were performed for suspected leak. Sensitivity, specificity, PPV, and NPV were 87%, 98%, 92%, and 97%, respectively. Among positive exams (36/184, 20%), extraluminal contrast, gas, and fluid collection were present in 75%, 78%, and 72% of cases versus 0%, 44%, and 24% in negative exams. Patients with confirmed leaks had significantly longer median LOS (26 vs. 8 days, p < 0.001) and greater imaging utilization (median 12 vs. 4 exams, p < 0.001). CONCLUSION: This CT UGI protocol demonstrates high specificity and NPV for gastroduodenal leak detection, supporting its utility for both suspected and routine postoperative leak evaluation.