W1898 Interobserver Agreement for Impedance Manometry Findings in Patients with Non-Obstructive Dysphagia

Abstract

Introduction: Impedance manometry (MII-EM) allows a more comprehensive evaluation of esophageal function by concomitantly measuring pressure changes and bolus transit. Still, there is limited information on the reliability and inter-observer agreement on MII-EM findings in patients with non-obstructive dysphagia. Aim: To evaluate the inter-observer agreement for impedance manometry readings in patients with non-obstructive dysphagia during liquid and solid swallows. Methods: Patient referred for evaluation of dysphagia underwent stationary MII-EM using a solid state catheter with 5 pressure channels and 5 impedance segments. Pressure changes were measured in the esophageal body 5, 10, 15 and 20cm above the lower esophageal sphincter (LES) and bolus presence data 2, 5, 10, 15 and 20 cm above the LES. Each subject received 10 saline and 10 yoghurt swallows in recumbent position. Tracings were reviewed independently by 4 investigators. Bolus presence time (BTT), distal esophageal amplitude (DEA) and lower esophageal sphincter residual pressure (LESRP) were quantified. Overall manometric and bolus transit abnormalities were based on previously established criteria (Am J Gastroenterol. 2004;99:1011). Results: From 20 patients (12 f, mean age 50, range 21-69 years) 15 (75%) had normal manometry, 2 IEM, 2 nutcracker esophagus and 1 poorly relaxing LES. 80% of patients had normal bolus transit. We found an excellent correlation between the readings of all 4 raters for DEA (intraclass correlation coefficient (ICC) 0.999), BTT (ICC 0.991) and LESRP (ICC 0.979). There was a very good interobserver agreement for both manometric and impedance findings with kappa values ranging from 0.77 to 0.99 (Table 1) Conclusion: The good inter-observer agreement for bothmanometric and bolus transit findings supports the reliability of combined impedance-manometry in clinical practice. Table 1: Kappa statistics for manometry and impedance findings