CASE REPORT: Vocal acoustic characteristics of adenotonsillar hypertrophy and adenotonsillectomy in young child.

Background: Adenotonsillar hypertrophy, which is the cause of the majority of sleep disorders in children, can cause various problems. One of the symptoms is a voice disorder, but the details remain unclear. The reasons 1) excluded young children (3-6 y.o.), even though tonsillar hypertrophy affects from previous studies, 2) are on a wide range of participants ages, 3) fail to investigate the effects associated with vocal abuse or misuse, and 4) do not take into account the effects of postoperative sore throat (POST) associated with the surgery or tracheal intubation on voice quality, resulting in inconclusive results. This study aimed to perform a vocal acoustic analysis on the effects of adenotonsillar hypertrophy and adenotonsillectomy by eliminating these obstacles as much as possible. The results of this study will help to recognize the type of this symptoms-related voice disorders, and information based on acoustical objective indexes for medical doctors, patients, and their families. Case presentation: We collected the vocalizations of patient, he was a boy aged three years, for the 10 days before the surgery, and for five days at 1, 3, and 6 months postoperatively. Voices were recorded twice, once in the morning (AM) and once in the evening (PM), and used for acoustic analysis. Although this is a single case, no previous report has investigated the effects of adenoids on voice in such a long-term and detailed manner, and it’s a valuable report. Results: The parameters indicating voice pitch (fundamental frequency: Fo), glottic insufficiency (noise-to-harmonic ratio: NHR), and vocal fold stiffness (degree of subharmonic: DSH) improved after surgery. These results suggested that the tonsillar hypertrophy may contribute to the phonotrauma, and adenotonsillectomy seems to have positive effect not only on the improvement of obstructive sleep apnea (OSA) in child, but also on the development of voice.