Objective: To compare the evaluation of vocal fold mobility between flexible nasal laryngoscopy (FNL) and a handheld application-based translaryngeal ultrasound (TLUS) platform.
Study design: Prospective analysis included patients with unknown vocal fold mobility status who underwent FNL and TLUS.
Setting: Tertiary referral center.
Subjects and methods: TLUS was performed on 23 consecutive children (<18 years old) presenting for laryngoscopy due to unknown vocal fold mobility status. After the recording of three 10-second TLUS videos as well as FNL, the study was divided into 2 parts: parental assessment of laryngeal ultrasound at the time of patient evaluation and random practitioner assessment of ultrasound videos.
Results: We describe 23 patients who underwent TLUS and FNL. Ten patients (43.5%) had normal vocal fold function bilaterally, and 13 (56.5%) had either left or right vocal fold immobility. Family members and physicians correctly identified the presence and laterality of impaired vocal fold mobility in 22 of 23 cases (κ = 0.96). The sensitivity, specificity, positive predictive value, and negative predictive value of FLUS in diagnosing vocal fold immobility were 92.3%, 100%, 100%, and 90.9%, respectively. Random practitioners accurately identified the presence and laterality of vocal fold immobility under all circumstances.
Conclusion: A handheld application-based ultrasound platform is both sensitive and specific in its ability to identify vocal fold motion impairment. Portable handheld TLUS has the potential to serve as a validated screening examination, even by inexperienced providers, and in specific cases may obviate the need for an invasive transnasal laryngoscopy.
Keywords: pediatric; ultrasound; vocal fold paralysis.