S1319 Evaluating Interobserver Agreement of AFS and Hill Grading Systems for Gastroesophageal Junction Assessment: A Study of Endoscopic Imaging in Hiatal Hernia Repairs

Introduction: Gastroesophageal reflux disease (GERD) is a prevalent and debilitating esophageal condition. In 1996, Hill et al. introduced a practical classification for assessing the competence of the esophagogastric sphincter mechanism by inspecting the gastroesophageal flap valve in inversion, categorizing it into 4 grades. Despite its utility, the Hill grade classification has seen limited use due to perceived subjectivity. In response, the AFS classification aims to enhance objectivity by evaluating hiatus aperture, hiatal axial length, and flap valve presence. However, variability in endoscopic assessment among observers and potential influence from patient history pose challenges. Our study is the first to assess the interobserver AFS and Hill grades for assessing the gastroesophageal junction (GEJ). Methods: In this study, 46 patients who underwent hiatal hernia repair surgeries and had pre- and post-surgery esophagogastroduodenoscopies (EGDs) were included. A total of 92 gastroesophageal junction (GEJ) images from these endoscopies were provided in a blinded manner to 2 expert gastroenterologists. These experts were instructed to assign Hill and AFS grades to the GEJ images. Additionally, they were asked to provide measurements for the axial diameter and longitudinal length of any hernia if they identified its presence. To assess the level of agreement between the 2 gastroenterologists, a kappa agreement test was employed. Results: We observed a moderate level of agreement between the 2 gastroenterologists for the HILL grade (kappa = 0.559, 95% CI = 0.00-0.032) and a slightly weaker moderate level for the AFS score (kappa = 0.448, 95% CI = 0.00-0.032) in assessing the gastroesophageal junction. When examining hiatal hernia measurements, there was a moderate level of agreement for axial diameter (kappa = 0.546, 95% CI = 0.00-0.032) but a fair level for longitudinal length (kappa = 0.368, 95% CI = 0.00-0.032). Notably, a substantial agreement was found for determining the presence or absence of hernia (kappa = 0.642, 95% CI = 0.00-0.032). Conclusion: Our findings contribute to the ongoing discussion surrounding the objectivity and reliability of grading systems for GERD-related conditions. As clinical decisions and interventions are often guided by these assessments, further efforts to enhance the consistency and precision of endoscopic evaluations are warranted to improve the overall management of patients with gastroesophageal reflux disease.