Evaluating the Quality of Rigid Optic Videolaryngoscopy Image Taken Through Dental Protection Cap and Its Feasibility as Additional Barrier Method Against COVID-19

Videolaryngoscopy screening is essential to help assessing human larynx. The use of 70° optical fiber in association with image recording by analog or digital cameras is one of the methods adopted to perform this examination. Endoscopic exams can contaminate the equipment with several microorganisms. The pandemic caused by the new coronavirus reinforces the importance of developing efficient barrier methods to be adopted in videolaryngoscopy procedures. Although dental intraoral camera covers are a barrier method authorized by Brazilian health organs, it has not yet been used in videolaryngoscopy examinations. The aim of the current longitudinal, individualized, single-blind, prospective, self-controlled, and accurate study is to evaluate the quality of images generated through, and confidence level of, diagnosis based on videolaryngoscopy performed with intraoral dental camera equipped with disposable protection cap and connected to 70° rigid laryngoscope in vocally healthy individuals. Videolaryngoscopy examinations based on 70° rigid optics were performed in 13 euphonic and asymptomatic volunteers at an otorhinolaryngology specialist clinic; only 1 patient was excluded from the study. Images were taken with, and without, disposable intraoral dental camera protection cap; high-grade disinfection protocol was applied between examinations. Recorded videos were randomly distributed in a single-blind manner in order to be evaluated by four otorhinolaryngologists, who answered a questionnaire comprising three questions. Statistical analysis was used to compare groups – which were defined by the use, or not, of protection cap – based on Wilcoxon nonparametric test. Statistical significance was set at 5% with 95% confidence interval. There was no statistically significant difference in image quality between examinations performed with, and without, protection cap (P= 0.646) or in the diagnosis confidence level of examinations performed with, or without, the barrier method. The use of disposable protection cap on intraoral dental camera did not significantly change the quality of images taken through videolaryngoscopy performed with 70° rigid optics in vocally healthy patients.