325 Diagnostic Accuracy of Preoperative Investigations for Hiatus Hernia: A Single-Centre Retrospective Study

Abstract Aim To evaluate the diagnostic accuracy of commonly used preoperative investigations—oesophagogastroduodenoscopy (OGD), barium swallow, and oesophageal manometry—for detecting hiatus hernia (HH), using operative findings as the reference standard. Method A retrospective study was conducted on 241 patients who underwent surgery for HH at a single UK centre. All patients had operative confirmation of HH. The diagnostic performance of OGD, barium swallow, and manometry was assessed individually and in parallel combinations. Sensitivity and specificity were calculated using standard formulas. McNemar’s test was applied to assess statistical significance of discordant results. Simulated diagnostic scores were used to generate ROC curves and calculate area under the curve (AUC) to compare test accuracy. Results OGD demonstrated the highest standalone sensitivity at 81.3%, followed by barium swallow (68.6%) and manometry (46.7%). Parallel testing with OGD + Barium achieved 100% sensitivity. McNemar’s test confirmed statistically significant diagnostic disagreement between barium vs OGD and manometry vs OGD (p<0.001). Simulated ROC curve analysis showed superior diagnostic performance for the OGD + Barium combination, with an AUC of 1.00. Conclusions OGD is the most reliable and accurate single investigation for diagnosing HH preoperatively. Parallel testing with barium swallow improves diagnostic sensitivity and may be appropriate in cases where OGD is negative or inconclusive. Manometry offers limited diagnostic value for HH detection but may be reserved for functional assessment. A structured diagnostic pathway centred on OGD is recommended for optimal clinical decision-making.