ASSESSMENT OF THE INFANT AIRWAY WITH VIDEORECORDED FLEXIBLE LARYNGOSCOPY AND THE OBJECTIVE ANALYSIS OF VOCAL FOLD ABDUCTION

Accurate diagnosis of upper airway abnormalities by flexible laryngosc opy in infants is hampered by rapid laryngeal motion and lack of patie nt cooperation, This study evaluates the added role of videorecorded f lexible laryngoscopy and the objective measurement of vocal fold abduc tion in improving the diagnosis of upper airway abnormalities in infan ts, Seventy-eight infants had videorecorded flexible laryngoscopy perf ormed as part of their evaluation of a suspected airway disorder. Thes e recordings were reviewed by three otolaryngologists for confirmation of the clinical diagnosis, From the video image, the maximum angle of vocal fold abduction was measured with image analysis software. Of 78 patients 40 had supraglottic or glottic abnormalities, 9 had nasal or nasopharyngeal obstruction, 9 had subglottic abnormalities (diagnosed subsequent to videolaryngoscopy), and 15 patients had normal findings on examination. Of those with laryngeal abnormalities, laryngomalacia was the most common diagnosis (23 of 78). Vocal fold paralysis was pr esent in 4 patients. A separate group (9 of 78) of patients was identi fied as having symmetric bilateral limitation of vocal fold abduction. Laryngeal dyskinesia was diagnosed in these 9 patients. The mean valu es of maximal vocal fold abduction were as follows: (I) normals, 59.5 degrees; (2) laryngomalacia, 57.0 degrees; (3) paralysis, 26.6 degrees ; and (4) incomplete abduction with laryngeal dyskinesia, 27.6 degrees . Videolaryngoscopy is a valuable tool for documentation, parent educa tion, and analysis of infant laryngeal abnormalities, Repeat viewing o f the video examination and frame-by-frame analysis improve the diagno stic accuracy. Using this approach, we have calculated the anterior gl ottic abduction angle in the normal and abnormal infant larynx. In add ition, we have identified a group of infants with incomplete abduction of the vocal folds that appears to be different from that found in vo cal cord paralysis.