Single case study of voice quality following injection of hyaluronic acid in a 10 year old child
Wendy M M Cohen () and David M Wynne ()
Children born with narrowing of the subglottic airway, known as congenital subglottic stenosis usually present with biphasory stridor. Such children often require medical management to support their respiratory function, and some undergo reconstructive surgery to repair the stenosis. A single case study is reported of a child (D) who underwent surgery as a neonate for type III subglottic stenosis by laryngotracheoresection and rib grafting. During the laryngofissure the anterior aspect of the right vocal cord was damaged and underwent atrophy. Now aged 10, D continues to have a small subglottic / tracheal stenosis, giving him mild stridor. As an active 10 year old boy, he is able to participate in a wide range of educational and extra-curricular activities despite his respiratory limitations. Recently, D has become increasingly aware of limitations of his voice quality on functional activities. Injection of hyaluronic acid into the vocal folds has been known to provide improved voice quality in adults though there are no known cases are reported of this procedure in children. This paper reports voice outcomes following injection on two occasions of hyaluronic acid into the Reinke’s space in D’s right atrophied vocal fold. Audio recordings were made of D producing the sustained vowels [a] and [i], six reading sentences from the CAPE-V protocol and a reading passage pre, post and one month follow up of the second hyaluronic injection procedure. These recordings were presented randomly to an expert voice clinician who rated them using the Grade (G), Roughness (R) and Breathiness (B) parameters of the GRBAS protocol and also made comment about whether each recording was pre, post or follow up. Acoustic analysis was also undertaken on each of the recordings, measuring jitter, shimmer and harmonics-to-noise ratios. Six of the nine recordings were correctly identified perceptually as being completed at the follow up appointment. G, R and B ratings for these six recordings moved from moderate/severe to mild/moderate on the GRBAS scale. Acoustic analysis indicates improvement towards the considered normal range for [a] and the reading passage on jitter, shimmer and harmonics-to-noise ratio; improvement towards the considered normal range for [i] on jitter and shimmer and movement to within the normal range on harmonics-to-noise ratio for [i]. D and his family report increased voice quality at home and during school and extra-curricular activities. Ongoing monitoring of the maintenance of vocal quality improvement is being undertaken. Further injection of hyaluronic acid may be considered pre-puberty. Further surgical management may be considered post-puberty as necessary for maintaining adequate vocal function in adulthood. There are implications for future multidisciplinary management of children presenting with impaired voice quality as a result of neonatal complications and surgical intervention. Further research is proposed by the team into the long term voice outcomes for children who have undergone this type of surgical procedure. Speech and language therapists have a key role in supporting such children to achieve maximum vocal function and vocal quality of life.