Transcutaneous laryngeal ultrasonography: A promising tool for otolaryngologists during COVID-19

With the current COVID-19 outbreak, otolaryngologists are most exposed to the risk of infection due to the nature of the specialty.This is why they are required to find safer diagnostic alternatives minimizing aerosol-generating procedures. The aim of this study is to explore the accuracy of transcutaneous laryngeal ultrasonography (TLUSG) in order to assess vocal fold movement.

We performed blindly both TLUSG and flexible fiberoptic laryngoscopy(FFL) on 38 patients, from March to June 2020. Patients were divided into two groups:the former with normally mobile vocal folds and the latter with unilateral vocal fold paralysis.

On FFL findings, 10/38 patients (26,31%) had unilateral vocal fold paralysis; on TLUSG results, 9/38 patients (23.68%) presented impaired vocal fold motion. In comparison to laryngoscopy, the sensitivity, specificity, positive predictive value and negative predictive value of TLUSG for assessment of vocal fold mobility was 80%, 96.42%, 88.88%, 93.10% respectively. A significant association between the two techniques was found on the Chi-square test: X² = 19.7722 (p value <0.00001). Cohen's K value showed a substantial agreement: K = 0,79.

Although TLUSG could undoubtedly not replace laringoscopy, it represents a noninvasive and useful diagnostic tool for otolaryngologists especially during covid-19 pandemic.Data collected about its high sensitivity and specificity suggest that TLUSG could be a reliable method to screen vocal fold paralysis without performing aerosol-generating procedures, thus providing clear visualization of laryngeal real-time movements, even in non-compliant or high-risk infection patients. Our results allow us to consider TLUSG as part of the preoperative assessment of vocal folds in patients undergoing thyroidectomy.