Normal Thickness Ranges for the Adult Korean Epiglottis Using Ultrasonography

ABSTRACT

PURPOSE: The purpose of this study was to assess the reliability of ultrasonography to image the epiglottis and to determine a thickness range based on healthy Korean adults. METHODS: Anterior neck images were obtained in 100 healthy Koreans (52 males and 48 females) using ultrasonography. Sonographically, the epiglottis appeared as a curvilinear, hypoechoic structure with an echogenic preepiglottic space. 20 of 100 subjects, each patient underwent two ultrasound measurements by the same examiner to assess for intra-examiner reliability, followed by two additional measurements performed by a second examiner to assess for inter-examiner reliability. RESULTS: Intraclass correlation coefficient revealed excellent reliability (intra-examiner 0.901, inter-examiner 0.887). The average Korean epiglottis thickness was measured to be 2.31+/-0.22 mm (range 1.88 mm to 2.84 mm), with greater thickness noted in men (2.41+/-0.21 mm) when compared to women (2.21+/-0.18 mm) (p <0.001). There was significant correlation between epiglottis thickness and body surface area (r=0.533), weight (0.517), height (0.437) and body mass index (0.372). Average examination time was recoded to be 17.84+/-13.09 seconds. CONCLUSION: Bedside ultrasonography is rapid, safe, easy to perform and can accurately evaluate the epiglottis as seen in our study. Because of excellent reliability, it is possible to establish diagnostic criteria.