Dysphonia in very preterm children: incidence, pathology and responsiveness to therapy
Dysphonia is defined as deviance in the sound quality of the voice produced during speech. An individual’s voice is considered dysphonic when it differs perceptually from norms associated with gender, age, stature and culture, or when it impedes the activities of daily living. Dysphonia can have a significant impact on the quality of life of those affected, for example, as adverse effects on academic, social and employment outcomes. Children with dysphonia are evaluated negatively on characteristics such as physical appearance and personality traits, in comparison to their peers with normal voices.
Mild dysphonia in childhood is common, affecting up to 40% of otherwise typically-developing children. Communication behaviours typically seen in children, such as shouting, making noises in play and prolonged voice use at elevated volumes place strain on the vocal mechanism and cause superficial mucosal injury, resulting in hoarseness. More severe forms of dysphonia, arising from structural laryngeal pathology, are rare. Yet, children born very preterm are at high risk of developing dysphonia. Many require ventilator support in the neonatal period. Tracheal intubation has been associated with laryngeal injury in neonates. Our laboratory has published a pilot study into dysphonia at school age in children born extremely preterm, and demonstrated that there is an association between intubation variables and voice outcomes. However, to date, there have been no large-scale investigations into the voice outcomes of very preterm children. Further, the prognosis for such children is unknown.
The main objectives of this study are to: identify the incidence of dysphonia in very preterm children, investigate the laryngeal pathology of those children with significant voice abnormalities and to trial a behavioural intervention to determine whether such treatment affects voice quality in very preterm children with dysphonia.
Why my research is important
As the number of survivors of very preterm birth increases, advances in medicine and technology continue to result in lower morbidity among very preterm children. However, invasive ventilation is inevitable in the care of many such children. For some, dysphonia may be the only ongoing consequence of their preterm birth that limits their acitivities and participation. Whilst not life-threatening in childhood, dysphonia can have ongoing consequences across the lifespan. Children who are unable to project their voices may find it diffuclt to participate in organised teams sports, and in academic subjects such as English, Drama and Technology and Enterprise. Additionally, it is estimated that one-third of the workforce in developed countries are professional voice users: that is, they require a clear, reliable voice in order to discharge their employment duties (e.g., police officers, sales assistants, health professionals, hospitality staff and receptionists).
Our study will lead to better understanding of the incidence, risks for and nature of voice problems in very preterm children, and will also demonstrate whether voice therapy has any effect on voice quality in these cases.