The dysphonic videolaryngoscopy with stroboscopy paradox and challenge of acquired subglottic stenosis after laryngotracheal reconstruction.

OBJECTIVE: There's no greater challenge in pediatric laryngology than diagnosis and treatment of chronic dysphonia following laryngotracheal reconstruction of acquired subglottic stenosis. Videolaryngoscopy with stroboscopy provides incomparable diagnostic information to fiberoptic endoscopy. Unfortunately, this pediatric subpopulation which would benefit the most from videolaryngoscopy with stroboscopy infrequently does. We present the unique videolaryngostroboscopic patterns with their diagnostic and treatment implications in this complex population.

METHODS: From a total database of 113 children with histories of subglottic stenosis and/or airway reconstruction between January 1, 2000 and September 30, 2011, successive frames of recorded videolaryngostroboscopies in twenty-three dysphonic children were reviewed. These stroboscopies were compared to age and gender matched controls with dysphonia due to vocal nodules consecutively analyzed from the time period 2009-2011. To validate the similarity of our patient population to others previously reported, we also collected the standardized perceptual, acoustic, and aerodynamic measures of voice analysis and parent/patient reported quality of life.

RESULTS: The voices of patients' pre- and post-airway reconstruction are typically moderately breathy and harsh in voice quality with the majority exhibiting a restricted pitch range and vocal strain. Reduced vocal volume intensity and low habitual speaking pitch were common. Overall, the severity of voice fell within the moderately dysphonic range. Despite universal glottic aperture incompetence, muscle tension dysphonia of the true vocal cords was seen. The glottic muscle tension was confirmed indirectly by noting a consistent "posterior cricoarytenoid bulge." In addition, our group termed a unique pattern of "circumferential supraglottic squeeze" which included both lateral plica ventricularis (false vocal folds) and anteroposterior squeeze opposing the arytenoids to the epiglottic petiole (termed by our group as "arytenoid hooding"). In no patients were the true vocal cords fully visualized. While superficially appearing as hyperfunction, these findings paradoxically represented compensation for laryngeal hypofunction marking the hyperfunction not the problem but a symptom. Actual "mucosal waves" were seen involving the false vocal cords.

CONCLUSIONS: Videolaryngoscopy with stroboscopy results in patterns that are not only unique to patients after airway reconstruction for subglottic stenosis but are also critical for both surgical and non-surgical treatment of chronic dysphonia in these children.