The Usefulness of the Measurement of Esophagogastric Junction Distensibility by EndoFLIP in the Diagnosis of Gastroesophageal Reflux Disease

Background/Aims: Increased esophagogastric junction (EGJ) relaxation is the most important mechanism involved in gastroesophageal reflux disease (GERD).An endoscopic functional luminal imaging probe (EndoFLIP Ⓡ ) is a device used to quantify EGJ distensibility in routine endoscopy.The aim of the current study was to assess the usefulness of EndoFLIP Ⓡ for the diagnosis of GERD compared to normal controls. Methods:We analyzed EndoFLIP Ⓡ data from 204 patients with erosive reflux disease (ERD), 310 patients with nonerosive reflux disease (NERD), and 277 normal subjects.EndoFLIP Ⓡ uses impedance planimetry to measure 16 cross-sectional areas (CSAs) in conjunction with the corresponding intrabag pressure within a 4.6 cm cylindrical segment of a fluid-filled bag.The EGJ distensibility was assessed using 40 mL volume-controlled distensions.Results: The mean distensibility index values were 13.98 mm 2 /mm Hg in ERD patients, 11.42 mm 2 /mm Hg in NERD patients, and 9.1 mm 2 /mm Hg in normal subjects.There were significant differences in EGJ distensibility among the three groups (p<0.001).In addition, the CSAs were significantly higher in the ERD (291.03±160.77mm 2 ) and NERD groups (285.87±155.47 mm 2 ) than in the control group (249.78±144.76mm 2 , p=0.004).We determined the distensibility index cutoff value of EGJ as 10.95 for the diagnosis of GERD by receiver operating characteristic curve analysis. Conclusions:The EGJ distensibilities of GERD patients were higher than those of normal subjects, regardless of the presence of reflux esophagitis.Thus, the measurement of EGJ distensibility using the EndoFLIP Ⓡ system could be useful in the diagnosis of GERD.(Gut Liver 2021;15:546-552)