Validation of Clinically Relevant Thresholds of Esophagogastric Junction Obstruction Using FLIP Panometry.
Background & Aims: This study aimed to assess the accuracy of functional luminal imaging probe (FLIP) panometry to detect esophagogastric junction (EGJ) obstruction assigned by high-resolution manometry (HRM) and the Chicago Classification version 4.0 (CCv4.0).
Methods: Six hundred eighty-seven adult patients who completed FLIP and HRM for primary esophageal motility evaluation and 35 asymptomatic volunteers (controls) were included. EGJ opening was evaluated with 16-cm FLIP during sedated endoscopy via EGJ-distensibility index (DI) and maximum EGJ diameter. HRM was classified according to CCv4.0 and focused on studies with a conclusive disorder of EGJ outflow (ie, achalasia subtypes I, II, or III; or EGJ outflow obstruction with abnormal timed barium esophagogram) or normal EGJ outflow.
Results: All 35 controls had EGJ-DI >3.0 mm2/mmHg and maximum EGJ diameter >16 mm. Per HRM and CCv4.0, 245 patients had a conclusive disorder of EGJ outflow, and 314 patients had normal EGJ outflow. Among the 241 patients with reduced EGJ opening (EGJ-DI <2.0 mm2/mmHg and maximum EGJ diameter <12 mm) on FLIP panometry, 86% had a conclusive disorder of EGJ outflow per CCv4.0. Among the 203 patients with normal EGJ opening (EGJ-DI ≥2.0 mm2/mmHg and maximum EGJ diameter ≥16 mm) on FLIP panometry, 99% had normal EGJ outflow per CCv4.0.
Conclusions: FLIP panometry accurately identified clinically relevant conclusive EGJ obstruction as defined by CCv4.0 in patients evaluated for esophageal motor disorders. Thus, FLIP panometry is a valuable tool for both independent and complementary evaluation of esophageal motility.