A Novel Assessment Method With Ultrasound for Obstructive Tonsillar Hypertrophy in Children

Abstract

Objectives: To develop a new method for the objective evaluation of airway obstruction due to tonsillar hypertrophy using ultrasound (US) in children. Methods: The oropharynx was examined in patients, and tonsil grades were evaluated according to the staging system of Brodsky et al (Int J Pediatr Otorhinolaryngol 1987; 13:149–156). The narrowest intertonsillar distance (ITD) and widest transverse length of the tongue base (TLTB) were then measured by US, and their ratio was calculated. The clinical value of US was investigated for the classification of tonsillar hypertrophies as nonobstructive or obstructive by matching the patients’ clinical grades with the US data. Results: A total of 102 patients (age range, 2–12 years) were included in the study. According to the Brodsky staging system, 44.1% and 55.9% of the patients were in nonobstructive (stages I and II) and obstructive (stages III and IV) tonsillar hypertrophy groups, respectively. The area under the curve was 0.991 (95% confidence interval, 0.977–0.999) according to a receiver operating characteristic curve analysis between the Brodsky staging and the ITD/TLTB ratio. The optimal cutoff value for the ITD/TLTB ratio for the diagnosis of obstructive tonsillar hypertrophy was found to be 0.3 or less, which had 96.5% sensitivity and 95.6% specificity. Conclusions: The degree of airway obstruction due to tonsillar hypertrophy can be objectively determined by US in children. An ITD/TLTB ratio of 0.3 or less was found to be compatible with obstructive tonsillar hypertrophy. This new and easily applicable evaluation method may provide considerable value and guidance for tonsillectomy decisions. © 2020 American Institute of Ultrasound in Medicine