%0 Journal Article
%T A Simple Endoscopic Technique for Measuring the Cross-Sectional Area of the Upper Airway in a Rabbit Model.
%A Wistermayer PR
%A McIlwain WR
%A Ieronimakis N
%A Rogers DJ
%J Ann Otol Rhinol Laryngol
%V 127
%N 4
%D Apr 2018
%M 29478328
%F 1.973
%R 10.1177/0003489418759361
%X OBJECTIVE: Validate an accurate and reproducible method of measuring the cross-sectional area (CSA) of the upper airway.
METHODS: This is a prospective animal study done at a tertiary care medical treatment facility. Control images were obtained using endotracheal tubes of varying sizes. In vivo images were obtained from various timepoints of a concurrent study on subglottic stenosis. Using a 0° rod telescope, an instrument was placed at the level of interest, and a photo was obtained. Three independent and blinded raters then measured the CSA of the narrowest portion of the airway using open source image analysis software.
RESULTS: Each blinded rater measured the CSA of 79 photos. The t testing to assess for accuracy showed no difference between measured and known CSAs of the control images ( P = .86), with an average error of 1.5% (SD = 5.5%). All intraclass correlation (ICC) values for intrarater agreement showed excellent agreement (ICC > .75). Interrater reliability among all raters in control (ICC = .975; 95% CI, .817-.995) and in vivo (ICC = .846;, 95% CI, .780-.896) images showed excellent agreement.
CONCLUSIONS: We validate a simple, accurate, and reproducible method of measuring the CSA of the airway that can be used in a clinical or research setting.