Clinical Trial Details
— Status: Active, not recruiting
Administrative data
| NCT number |
NCT04107337 |
| Other study ID # |
RECHMPL19_0262 |
| Secondary ID |
|
| Status |
Active, not recruiting |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
September 1, 2020 |
| Est. completion date |
December 25, 2023 |
Study information
| Verified date |
September 2020 |
| Source |
University Hospital, Montpellier |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Singers are over-represented in phoniatric consultations; they present increased risk of
developing voice disorders. The most common lesion found in singers is nodule. It comes from
vocal straining characterized by the use of a pressed phonation mode, resulting in an
increase subglottal pressure and a decrease flow rate. Voice therapy aims to restore a more
relaxed phonation. There is a growing interest in semi-occluded vocal tract exercises with a
straw in therapy; they have positive effects, particularly in terms of aerodynamic parameters
such as subglottal pressure and oral airflow. After these exercises, subglottal pressure
decreases and oral airflow increases. In other words, patient adopts a more relaxed phonation
mode. Several studies have investigated the effect of these straw exercises on dysphonic
patients i.e. on speaking voice; no study to date has explored the effect of these exercises
on dysodic subjects i.e. on singing voice.
The aim of this study is to evaluate the impact of straw exercises compared to open-mouth
exercises on aerodynamic parameters in dysodic women singers with nodules.
Description:
Singers are over-represented in phoniatric consultations; 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 vocal change that makes them consult earlier than non-singers. In addition, their
complaints are specific to singing voice.
In phoniatrics, at the CHU Gui de Chauliac in Montpellier, singers (amateurs and
professionals) represent one third of phoniatric patients. 80% of them are diagnosed with
dysodia. Dysodia refers to singing voice disorders, in the same way as dysphonia 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.
Prevalence of dysodia is higher among women. This vocal disorder is most often associated
with laryngeal pathology. Nodular lesions are most common in singers as in general
population. Nodules are the consequence of vocal straining, also known as vocal
hyperfunction.
Singing means learning, more or less finely, depending on the level of training and singing
style, coordination between breath, vocal fold vibrations and resonators, the so-called
pneumo-phono-resonant adaptations. To have balanced phonation, singer must properly dose the
air pressure he applies under his vocal folds, have a sufficient flow rate and adapt muscular
tension of the vocal folds (neither too strain nor too loose). In this mode of phonation,
voice resonates without difficulty. On the other hand, during vocal straining, singer will
put too much subglottal pressure decreasing flow rate, which creates a laryngeal tightening
and can eventually cause nodules. The pressure threshold required to initiate a sound
(phonation pressure threshold) is then increased. Vocal gesture is therefore inappropriate
and the voice becomes ineffective.
After diagnosis of dysodia and vocal assessment to identify the patient's difficulties, the
patient is referred to speech-language pathologist for voice therapy. According to the vocal
difficulties identified, speech therapist defines the therapeutic objectives that will be
adapted to each patient and individualized according to the diagnosis, the singer's profile,
but also his objectives and his investment. Voice therapy aims not only to prevent the onset
or aggravation of vocal disturbances but also to remove or compensate for voice limitations
by reconditioning vocal gesture to make it more effective. In the case of nodular lesions,
voice therapy therefore aims to reduce vocal straining.
There is no specific therapeutic tool for singers. As in speaking voice, speech-language
pathologist uses technical aids as well as indirect and direct therapies. The main technical
aid proposed is amplification of voice with a microphone in the event of vocal misuse or
abuse, i.e. when the vocal load is too high. Indirect therapy consists of giving vocal
hygiene advice, in order to eliminate causes of voice disorder and to establish a vocal
economy program with the patient. On the other hand, direct therapy consists in directly
modifying vocal gesture through vocal exercises. This therapy is based on the premise that
the subject has acquired an inappropriate vocal gesture that the therapist identifies and
corrects through vocal exercices. Direct therapy is based on three successive steps: i)
rehabilitation of respiratory gesture, ii) work on a vocal emission without associated
tension, so as to eventually reduce laryngeal lesions, and iii) awareness of the role of
resonance cavities.
Concerning work of vocal emission, to reduce vocal straining, many therapies are based on
semi-occluded vocal tract exercises, also called physiological exercises. They include labial
and lingual trills (lip and tongue vibration), nasal consonants, voiced fricative consonants,
kazoo as well as tubes or straws. Straw exercises are the most reproducible due to the
precise calibration of occlusion. Montpellier University Hospital is the national leader in
the development of these straw exercises in France, with a particular focus on flow control
during the exercises.
The purpose of these exercises is to teach the patient to use proper air pressure and flow
while singing. Several studies are investigating effects of these straw exercises on
aerodynamic parameters of subglottal pressure, phonation pressure threshold and oral airflow.
It appears that:
- straw exercises reduce estimated subglottal pressure. For non-singers, this is true
after 15 minutes of exercises as well as after 8 rehabilitation sessions. For singers,
results are more variable and concern only singers without voice disorders. No studies
have explored effect of straw exercises on estimated subglottal pressure in dysodic
singers.
- straw exercises lower phonation threshold pressure (PTP). Most studies find a decrease
in PTP after straw exercises, either in non-singer patients with speaking voice
disorders or in choristers without voice disorders. No studies have explored effect of
straw exercises on PTP in dysodic singers.
- Literature does not provide information on impact of straw exercises on oral airflow. In
euphonic subjects (without vocal disorder), whether singers or not, majority of studies
find an increase in airflow after straw exercises. Only one study found no difference in
airflow after straw exercises, while airflow increased after vocal exercises without
straw (vocalized). In dysphonic patients, no difference in flow rate is observed after
straw exercises. No studies have explored effect of straw exercises on airflow in
dysodic singers.
Thus, no study to date has explored effect of straw exercises on aerodynamic parameters
(estimated subglottal pressure, PTP, oral airflow) in dysodic singers. Singers are often
targeted as a study population because of their familiarity with semi-occluded exercises but
not to further explore singing voice. For example, in a study only one frequency is tested
(pitch and comfortable intensity), so singing voice is not further explored. However, the
economic and psychological impact of dysodia, particularly among professionals, is well
described in the literature.
In this project the investigator want to fill this gap by studying the singing voice effect
of straw exercises on the estimated subglottal pressure, PTP and oral airflow in dysodic
women singers. Do straw vocal exercises modify aerodynamic behaviour of dysodic women singers
with nodules after a rehabilitation session? Based on results of literature for speaking and
singing non-pathological voice, the investigator hypothesize that the estimated subglottal
pressure and PTP will decrease after straw exercise session while they will remain constant
after open mouth exercise session. Meanwhile, the investigator hypothesize that oral airflow
will increase following straw exercises while it will remain constant after open-mouth
exercises.
