Singing-voice Disorders and Aerodynamic Profiles in Dysodic Singers

Singers are over-represented in phoniatric consultation; they present increased risk of developing voice disorders whether they are amateurs or professionals. They represent a specific population among phoniatric patients because of their increased sensitivity to the slightest voice change that makes them consult earlier than non-. In addition, their complaints are specific to singing voice. The most common lesion found in singers is vocal-fold nodule. It comes from a vocal straining characterized by the use of a pressed phonation mode, resulting in an increased subglottal pressure and a decreased flow rate.

Singing-voice disorder is called dysodia in the same way as dysphonia, which refers to speaking-voice disorders. Dysodia results in a variety of symptoms. Acoustic signs are the most numerous: tonal anomalies (lack of accuracy, reduction of vocal range); dynamic anomalies (problem to sing softly or loudly); timbre abnormalities (vibrato problems, strained voice, roughness, difficulties on attacks). Dysodia also results in respiratory disorders, physical signs, psychological consequences and damage to hedonistic properties (loss of comfort, vocal endurance, musicality). It can reach amateur or professional singers. For professional singers, voice is the main working tool. When they have dysodia, professional difficulties can be temporary or even lead to the loss of work. In addition, dysodia can lead to financial loss and well-documented anxiety. For amateur singers, dysodia hinders their musical practice, thus limiting the recognized benefits of choral singing on cohesion, social integration and personal development. The diagnosis of dysodia is made after a laryngeal examination and a vocal assessment to identify patient's speech difficulties.

Voice assessment includes subjective voice analyses but also instrumental analyses that include acoustic, electrophysiological and aerodynamic voice measurements. The interest of aerodynamic parameters for the diagnosis of vocal pathologies is now widely demonstrated. These parameters include measurements of estimated subglottal pressure (ESGP), phonation threshold pressure (PTP) (minimum pressure to initiate a sound) and oral air flow (OAF). They depend on the level of training of singers and the type of vocal dysfunction. These aerodynamic data are collected with devices such as the Assisted Voice Evaluation Device (EVA2©) used in the laryngeal department of the Gui de Chauliac University Hospital. These pressure and flow parameters are higher in opera singers than in non-singers. In clinical practice, the ESGP and PTP are higher during vocal straining in dysphonic patients. Concerning OAF, results remain controversial: increase with vocal effort in euphonics non-singers; decrease with intensity increase in euphonic non-singers. Aerodynamic behaviours of dysodic singers have not yet been described, although they can help to better identify the singer's vocal difficulties and could be essential parameters for targeting more precisely rehabilitation exercises proposed in voice therapy.

In addition, most studies on prevalence of vocal disorders in singers come from the American continent. Very few descriptions of this population have been made in France. The few that exist are quite old or involve limited samples. Moreover, to date, no study has explored the aerodynamic profiles (flow and pressure) of singers, although these profiles are considered to be relevant clinical indicators to describe the singer's vocal difficulties and thus precise more specific therapeutic objectives.

In this context, our project aims to fill these gaps by describing a French population of singers consulting in phoniatrics and describing their aerodynamic behaviours. Do the singers' aerodynamic parameters (pressure, flow) reflect the dysfunctions in singing voice? Based on results of the literature on speaking and singing non-pathological voice, the investigators hypothesize that during voice assessment, the values of ESGP and PTP will be increased and that those of OAF will be decreased over the entire range of the singer in case of vocal pathology