Practical Application of EndoFLIP in the Evaluation of Patients with Dysphagia

Dysphagia evaluation traditionally proceeds from a history and upper endoscopy to high-resolution manometry (HRM), the reference standard for esophageal motor assessment; however, HRM is swallow-dependent, technically demanding, and yields inconclusive or discordant findings, particularly esophagogastric junction outflow obstruction (EGJOO) patterns, in a clinically meaningful proportion of studies. Functional lumen imaging probe (FLIP) Panometry was developed to complement HRM by using impedance planimetry to characterize esophagogastric junction (EGJ) opening and distension-induced esophageal body contractility during sedated endoscopy, offering a mechanical rather than purely pressure-based assessment of esophageal motor function. This review synthesizes the technique, standardized interpretive framework, and clinical evidence supporting FLIP Panometry across the dysphagia evaluation pathway. We describe the FLIP protocol and core metrics, the EGJ distensibility index, maximum EGJ diameter, contractile response pattern, and distensibility plateau that together generate a motility classification per the Dallas Consensus. We then detail FLIP’s principal clinical applications: clarifying inconclusive or discordant HRM, particularly EGJOO; providing complementary information at index endoscopy, where integration with endoscopic findings, such as the endoscopic CARS score, can expedite diagnosis and reduce reliance on subsequent HRM; serving as a physiologic outcome measure after achalasia-directed therapy; and characterizing fibrostenotic remodeling in eosinophilic esophagitis through esophageal body distensibility. FLIP’s safety profile, interrater reliability, and key limitations, including reduced sensitivity for spastic motor disorders relative to HRM, are reviewed, alongside emerging directions. Taken together, FLIP Panometry has become an established component of contemporary esophageal evaluation, providing mechanistic information that complements, rather than replaces, endoscopy, histology, barium radiology, and manometry in the comprehensive work-up of dysphagia.