1. Evelien D’haeseleer, Sofie Claeys, Kristiane Van Lierde
The Effectiveness of Manual Circumlaryngeal Therapy in Future Elite Professional Voice Users
Evelien D’haeseleer, Sofie Claeys, Kristiane Van Lierde
Department of Speech, Language, and Hearing Sciences
Ghent University

2. Elite professional voice users
Voice users where even a slight vocal difficulty causes serious consequences
Musical performers (and students)
Special and vulnerable group for developing voice disorders
High vocal load of the speaking and singing voice
High physical load
Not enough vocal and physical rest
Future professional voice users
At risk for developing poor vocal quality (Timmermans et al. 2002)
How can vocal quality be optimized?
Musical performers and musical students are a special and vulnerable group for developing voice disorders because of
a high vocal load of the speaking and singing voice
A high physical load (with an intensive training in dancing, modern dance, ballet, physical excersices….)
And finally because they do not take enough vocal and physical rest as they perform and practice late in the evening
In the literature Timmermans stated that future professional voice users are at risk for developing voice disorders due to the high vocal load and vocal abuse
So the question was: how can vocal quality be optimized in these future professional voice users?
Introduction

3. Manual Circumlaryngeal Therapy (MCT)
PURPOSE:
Relaxation of the laryngeal and perilaryngeal musculature and optimal position of the larynx in the neck to improve phonation.
METHODS:
Hyoid bone
The hyoid bone was encircled with the thumb and index finger, which were worked posteriorly until the tips of the major horns were felt.
Thyroid cartilage
The same circular movement procedure beginning from the thyroid notch and working posteriorly.
The posterior borders of the thyroid cartilage, were located, and the procedure was repeated.
Total larynx
With the fingers over the superior borders of the thyroid cartilage, the total larynx was worked downward and moved laterally at the same time.
MCT is a manual therapy that involves movements of the hyoid bone, the thyroid cartilage and the total larynx. The purpose of MCT is relaxation of the laryngal and perilaryngal musculatuture and optimal position of the larynx in the neck to improve phonation.
Therefore the hyoid bone is encircled with the thumb and index finger, which were worked posteriorly until the tips of the major horns were felt.
For the thyroid cartilage the same circular movement was performed beginning from the thyroid notch and working posteriorly. The posterior borders of the thyroid cartilage were located, and the procedure was repeated.
Finally, with the fingers over the superior borders of the thyroid cartilage, the total larynx was worked downward and moved laterally at the same time.
Introduction

4. Effectiveness MCT
MCT is effective in patients with hyperfunctional voice disorders. (Roy et al., 1993; Roy et al., 1997; Van Lierde et al., 2004)
Aronson (1990): manual therapy is the primary approach for patients with musculoskeletal tension disorders.
MCT is more effective compared to breathing exercises in patients with muscle tension dysphonia. (Van Lierde et al., 2008)
What is the impact of MCT on the vocal quality of (healthy) musical performers (students)
Purpose of this study
MCT has been shown to be particularly effective and results in improvements in vocal quality in patients with hyperfuntional voice disorders.
Aronson described the manual therapy as the primary approach for patients with musculoskeletal tension dysorders
And in previous research of our study group we found that MCT is more effective compared to breathing exercises in patients with muscle tension dysphonia
However it is not clear if MCT also has an impact on the vocal quality of healthy musical performers. So that was the purpose of this study
Introduction

5. Methods
SUBJECTS
17 students bachelor’s program in music and performing arts (musical)
6 men
11 women
Mean age: 24.4 year (range: year)
Perceptual normal voices (G0R0B0A0S0I0)
Otorhinolaryngological evaluation:
Good general health, normal hearing, normal physiology and anatomy of the larynx and the vocal cords (videostroboscopy, otoscopy and audiometry)
1 male student was excluded: organic voice disorder
Vocal load
Mean hours of singing classes per day: 1.6 hours (SD: 0.57h)
Mean hours of acting classes per day: 3.1 hours (SD: 1.40h)
They all had perceptually normal voices.
Otorhinolaryngological evaluation showed a good general health, normal hearing, normal physiology and anatomy of the larynx and the vocal cords in all subjects using videostroboscopy, otoscopy and audiometry.
Methods

6. Methods experimental group control group PROCEDURE n=8 n=7
Pretest-posttest control group design
experimental group control group
n= n=7
- voice assessment - voice assessment
- MCT 20 min - rest 20 min
In this study pretest posttest control group design was used. Students were randomly divided into an experimental and control group. In the experimental group MCT was performed during 20 minutes and a voice assessment pre and post MCT was performed. In the control group voice rest was applied during 20 minutes and the same voice assessment was performed as in the experimental group.
Methods

7. Methods OBJECTIVE VOICE ASSESSMENT Dysphonia Severity Index
Aerodynamic measurement
Maximal phonation time (s)
Voice Range Profile
Highest intensity, Ihigh(dB)
Lowest intensity, Ilow (dB)
Highest frequency, Fhigh (Hz)
Lowest frequency, Flow (Hz)
Acoustic analysis F0
Jitter (%)
Shimmer (%)
NHR
Dysphonia Severity Index
The objective voice assessment consisted of
Methods

8. Methods SUBJECTIVE VOICE ASSESSMENT Questionnaire:
The subjects were asked whether
the quality of the speaking and singing voice was worse, better, or the same as before the MCT.
speaking was more difficult, easier, or the same as before.
the vocal range was smaller, larger, or the same as before.
the sensations in the throat and the larynx after MCT were painful, open, the same, other.
the therapy itself was painful, not pleasant, no sensations, pleasant, other.
Secondly, a subjective voice assessment was performed using a questionnaire.
Methods

9. Statistical analysis
Paired non parametric comparison before and after MCT
Experimental group
Paired non parametric comparison before and after rest
Control group
Wilcoxon Signed Rank test for two related samples
Methods

10. Results experimental group
MCT
pre
post
median
Pc25
Pc75
 Pc25
 Pc75
p-value
Aerodynamic measurement
Maximal phonation time(s)
17.2
14.1
24.0
19.3
15.1
25.2
0.263
Vocal Range
Lowest intensity (dB)
53.0
52.0
56.0
52.5
53.5
0.293
Highest intensity (dB)
111.0
1080
116.0
109.0
108.0
113.5
0.672
Lowest frequency (Hz)
116.5
77.8
138.6
123.7
1.000
Highest frequency (Hz)
1174.7
932.3
1480.0
1357.3
1053.5
1570.6
0.310
Akoestic analysis
F0 (Hz)
222.2
166.8
234.8
237.1
113.1
240.4
0.612
jitter (%)
0.7
0.5
1.2
0.8
0.9
0.327
shimmer (%)
3.5
3.0
4.0
3.1
2.9
4.5
0.866
Noise to Harmonic Ratio
0.1
Dysphonia Severity Index
6.3
5.4
7.3
7.2
6.4
8.4
0.050
Results

11. Results control group Results Rest pre post Aerodynamic measurement
Rest
pre
post
median
Pc25
Pc75
 Pc25
 Pc75
p-value
Aerodynamic measurement
Maximal phonation time(s)
18.5
17.5
25.2
18.0
17.0
24.7
0.799
Vocal Range
Lowest intensity (dB)
53.0
50.0
54.0
55.0
0.071
Highest intensity (dB)
108.0
104.0
114.0
112.0
110.0
115.0
0.107
Lowest frequency (Hz)
138.6
77.8
146.8
130.8
0.581
Highest frequency (Hz)
1396.9
830.6
1568.0
1318.5
932.3
0.500
Akoestic analysis
F0 (Hz)
214.2
153.0
218.5
222.4
138.1
238.7
0.499
jitter (%)
0.6
0.3
0.9
1.1
0.735
shimmer (%)
3.3
2.3
3.5
3.0
2.6
3.1
0.237
Noise to Harmonic Ratio
0.1
0.498
Dysphonia Severity Index
6.8
6.0
9.1
6.5
5.1
8.8
Results

12. Results
Dysphonia Severity Index
p = 0.050
Results

13. Results questionnaire
Speaking and singing voice  n %  n 
worse
same
better
Quality speaking voice
0/8 0%
5/8
62.5%
3/8
37.5%
Quality singing voice
more difficult
easier
Speaking
smaller
bigger
Vocal Range
4/8
50% no
yes
Improvement of speaking or singing voice
2/8
25%
6/8
75%
Sensations larynx or throat  %
painful
open
Larynx
Throat
Evaluation of MCT n % N
not pleasant
no sensations
pleasant
MCT
1/8
12.5%
Results

14. Discussion Hypothesis Results: positive effect of MCT! Caution
MCT might maximize vocal capacities in this population as a result of a maximal relaxation of the laryngeal and perilaryngeal musculature, and an optimal position of the larynx in the neck.
Results: positive effect of MCT!
Increase of DSI (objective vocal quality)
6.3  7.2
Subjective experience
75%: improvement of the speaking or singing voice
50%: not pleasant or painful therapy
Caution
MCT can be carried out by ENT specialists and voice therapists with profound knowledge of the intrinsic and extrinsic laryngeal musculature, and after practical training managed by a specialist in the field of laryngeal manipulation techniques.
Discussion

15. Discussion Musical students Need for better guidance MCT HOWEVER
Intensive training in acting, singing and dancing
Harmful life style habits
Risk for poor vocal quality
Need for better guidance
Improve vocal hygiene (Timmermans et al. 2002)
Effective techniques to maintain or improve vocal quality
MCT
a possible technique for increasing or at least maintaining vocal quality during rehearsals or before a musical performance.
when vocal capacities are diminished to obtain relaxation of the vocal mechanism and consequently improve vocal quality.
HOWEVER
Further research is necessary
Future elite vocal performers, like musical students, are an important study group. They receive an intensive training in singing, performing and physical activities leading to a high vocal and physical load. Additionally, in response to their scholarly and social duties they do not imply enough vocal and physical rest, as they perform and practice late in the evening.11 (late rehearsals and performance, late and heavy meals, smoking, alcohol use,…)
a result future elite vocal performers are at risk to develop poor vocal quality.11 Therefore, next to strategies to improve vocal hygiene, effective techniques to maintain or improve vocal quality in this group of voice users are necessary. The objective and subjective results of this pilot study prudently suggest that musical students might benefit from MCT sessions. Hypothetically, vocal improvement after MCT might result from a maximal relaxation of the laryngeal and perilaryngeal musculature, an optimal position of the larynx in the neck and vocal warm up during phonation.
In the future, MCT might be implemented as a possible technique to increase or at least maintain vocal quality during repetitions or before musical performing. Secondly, MCT can be used when vocal capacities are diminished to obtain relaxation of the vocal mechanism and consequently improve vocal quality.
Discussion

16. Thank you for your attention