Abstract
OBJECTIVE: The aim of the study was to compare the esophagogastric junction (EGJ) compliance in response to controlled distension in fundoplication (FP) patients and controls using the functional luminal imaging probe (FLIP). BACKGROUND: FP aims to replicate normal EGJ distensibility. FLIP is a new technology that uses impedance planimetry to measure intraluminal cross-sectional area (CSA) during controlled distension. METHODS: Ten controls and ten FP patients were studied with high-resolution esophageal pressure topography (HREPT) and then the FLIP placed across the EGJ. Deglutitive and interdeglutitive EGJ distensibility was assessed with volume-controlled distension. The FLIP measured eight CSAs spaced 4 mm apart within a cylindrical saline-filled bag along with the corresponding intrabag pressure. RESULTS: The EGJ formed an hourglass shape during distensions with the central constriction at the diaphragmatic hiatus. The distensibility of the hiatus was significantly greater during deglutitive relaxation in both subject groups, but FP patients exhibited reduced EGJ distensibility and compliance compared to controls. During the interglutitive period, the corresponding increase in intrabag pressures at larger volumes were also greater in FP patients implying a longer segment of EGJ constriction. The EGJ distensibility characteristics did not correlate with HREPT measures. CONCLUSIONS: FLIP technology was used to compare EGJ distensibility in FP patients and control subjects. The least distensible locus within the EGJ was always at the hiatus. EGJ distensibility was significantly reduced, and the length of constriction increased in FP patients. Future FLIP studies will compare patients with and without post-FP dysphagia and gas bloat, symptoms suggestive of an overly restrictive FP.