Reliability of fluoroscopic examination of nasopharyngeal dorsoventral dimension change in pugs and French bulldogs

Abstract

Objective: To compare intra- and interobserver agreements in two-dimensional measurements of changes in nasopharyngeal dimensions during breathing in pugs and French bulldogs. Study design: Experimental randomized study. Animals: A total of 20 French bulldogs and 16 pugs. Methods: Four observers with different levels of experience measured the dorsoventral dimensions of the nasopharynx during inspiration and expiration on fluoroscopy videos. Measurements were performed at the maximal narrowing of the nasopharynx for the functional method and at the level of the tip of the epiglottis for the anatomically adjusted method. The intra- and interobserver agreements of the measurements, ratio of the dynamic nasopharyngeal change (ΔL), and grade of nasopharyngeal (NP) collapse (no, partial or complete) were evaluated. Results: The functional method resulted in intraobserver correlation coefficients of 0.532 (p 0.9 for both methods. Conclusion: Fair interobserver agreement was found for NP collapse grade (functional method), moderate intra- and interobserver agreements were found for NP collapse grade and ΔL (both methods) while intraobserver agreement for ΔL was good (functional method). Clinical significance: Both methods seem repeatable and reproducible but only for experienced radiologists. The use of ΔL may offer higher repeatability and reproducibility than grade of NP collapse regardless of the method used.