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CompletedNCT04764604Updated Aug 1, 2023Results posted

Evaluating the Feasibility of Acapella® Choice as a Dysphonia Treatment

An interventional study of Acapella Choice and Tube-in-water in Muscle Tension Dysphonia, Vocal Fold Palsy and Vocal Cord Paralysis, sponsored by University College, London. Completed at 1 site in United Kingdom. Open to participants aged 18 Years to 90 Years. Per ClinicalTrials.gov, last updated 2023-08-01.

Sponsored by University College, London · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
30
Allocation
Non-randomized
Ages
18 Years to 90 Years
Sex
All
01

Study summary

A feasibility study to identify the immediate effect on the voices of patients with voice disorders (muscle tension dysphonia, vocal fold palsy or presbylaryngis) produced by exercising with Acapella Choice as a form of semioccluded vocal tract exercise (SOVTE).

Read the detailed description

This feasibility study is the natural extension of the researchers' recently completed study (R\&D 16/0242) which assessed how the use of an Acapella Choice (Smiths Medical) positive expiratory pressure (PEP) device as a semi-occluded vocal tract exercise (SOVTE) impacted acoustic, electroglottographic and aerodynamic measures of the voice in a group of normophonic volunteers. In that study, Acapella Choice was found to offer significantly greater oscillating intraoral pressures than techniques in current clinical practice and was found to have measurable benefits in terms of producing a louder and more economical voice. It offered the largest oscillating pressures, likened to a 'massage' of the vocal organs, giving it great therapeutic promise for patients with excess vocal tract tension.

This study seeks to evaluate the immediate effects of Acapella Choice as a voice exercise in patients with Muscle Tension Dysphonia, Presbylaryngis and Vocal Fold Palsy, and compare this to the widely-used voice rehabilitation technique of phonation into a tube held under water (henceforward referred to as "Tube"). Patients will be recruited from four weekly Voice Clinics held at the Royal National Throat Nose and Ear Hospital where their diagnosis will be confirmed. They will be invited to attend a single experimental session during which time they will exercise both with Acapella Choice and with Tube. Baseline and outcome voice measures will be taken and a short questionnaire will be completed, eliciting perceptions of the two exercises and any changes which were felt to have resulted from them.

The researchers' previous work suggests that Acapella Choice as a SOVTE may offer significant clinical benefits in terms of improved efficacy of therapy. It is suggested that it also offers patients a more convenient and user-friendly form of exercise which may well improve compliance and result in better outcomes.

02

Conditions studied

  • Muscle Tension Dysphonia
  • Vocal Fold Palsy
  • Vocal Cord Paralysis
  • Presbylarynx
  • Dysphonia

Keywords

  • semi-occluded vocal tract exercise
  • positive expiratory pressure
  • tube phonation
  • Acapella
  • voice therapy
03

Who can participate

Ages eligible
18 Years to 90 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Able to understand written English without the need for an interpreter,
  • No diagnosed communication impairment
  • Endoscopically confirmed primary ENT diagnosis of either:

    1. muscle tension dysphonia (with no laryngeal abnormality),
    2. Vocal fold palsy
    3. Presbylaryngis.

Exclusion criteria

Exclusion Criteria:

  • Previous SLT input
  • Any of the following possible contraindications for PEP therapy:

    • Inability to tolerate increased work of breathing,
    • ICP (intracranial pressure) > 20mm Hg,
    • Recent facial/oral/skull surgery or trauma,
    • Oesophageal surgery,
    • Untreated pneumothorax,
    • Known or suspected tympanic membrane rupture/other middle ear pathology,
    • Haemodynamic instability,
    • Acute sinusitis,
    • Epistaxis,
    • Active haemoptysis,
    • Nausea
04

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Non-randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
30 participants (actual)

Study arms

  • Experimental
    Muscle Tension Group

    10 participants with a diagnosis of muscle tension dysphonia will carry out two experimental interventions, with a 30 minute vocal rest period in between interventions: 1. Three minutes of semi-occluded vocal tract exercise with both Acapella Choice 2. Three minutes of tube-in-water semi-occluded vocal tract exercise. Aerodynamic, acoustic and electroglottographic baselines will be taken before each intervention and repeated immediately post-intervention as outcomes. Participants will also provide a self-assessment of voice quality, perceived ease of voice production and perceived strength of voice before and after each intervention. Participants will additionally answer qualitative questions following each intervention regarding their perceptions of the task: ease performing, pleasantness, effort, practicality and likelihood of carrying out the task on a daily basis as a form of therapy.

    Device: Acapella Choice · Device: Tube-in-water

  • Experimental
    Vocal Fold Palsy Group

    10 participants with a diagnosis of (unilateral) vocal fold palsy will carry out two experimental interventions, with a 30 minute vocal rest period in between interventions: 1. Three minutes of semi-occluded vocal tract exercise with both Acapella Choice 2. Three minutes of tube-in-water semi-occluded vocal tract exercise. Aerodynamic, acoustic and electroglottographic baselines will be taken before each intervention and repeated immediately post-intervention as outcomes. Participants will also provide a self-assessment of voice quality, perceived ease of voice production and perceived strength of voice before and after each intervention. Participants will additionally answer qualitative questions following each intervention regarding their perceptions of the task: ease performing, pleasantness, effort, practicality and likelihood of carrying out the task on a daily basis as a form of therapy.

    Device: Acapella Choice · Device: Tube-in-water

  • Experimental
    Presbylaryngis Group

    10 participants with a diagnosis of presbylaryngis will carry out two experimental interventions, with a 30 minute vocal rest period in between interventions: 1. Three minutes of semi-occluded vocal tract exercise with both Acapella Choice 2. Three minutes of tube-in-water semi-occluded vocal tract exercise. Aerodynamic, acoustic and electroglottographic baselines will be taken before each intervention and repeated immediately post-intervention as outcomes. Participants will also provide a self-assessment of voice quality, perceived ease of voice production and perceived strength of voice before and after each intervention. Participants will additionally answer qualitative questions following each intervention regarding their perceptions of the task: ease performing, pleasantness, effort, practicality and likelihood of carrying out the task on a daily basis as a form of therapy.

    Device: Acapella Choice · Device: Tube-in-water

Interventions

  • DeviceAcapella Choice

    3 minutes of exercise consisting of blowing through the device (on setting '5') and phonating at the same time.

    Also known as: PEP, Semioccluded vocal tract exercise

  • DeviceTube-in-water

    3 minutes of exercise consisting of blowing through a silicone tube (10mm internal diameter) submerged in 5 cm of water whilst phonating at the same time.

    Also known as: Lax Vox, Resonance tube in water, Semi-occluded vocal tract exercise

05

What researchers measure

Primary outcomes

  1. Change in Baseline Cepstral/Spectral Index of Dysphonia (CSID)

    A quantitative, multivariate, dysphonia summary tool that incorporates spectral (low/high spectral ratio) and cepstral measures (cepstral peak prominence), and their standard deviations, extracted from a continuous speech or sustained vowel sample utilising the software Analysis of Dysphonia in Speech and Voice (Kay Pentax, Montvale, NJ). The software calculates CSID on the scale of 0-100, whereby 0 represents no evidence of hoarse voice, and 100 represents a maximum amount of hoarseness. See: Awan SN, Roy N, Dromey C. Estimating dysphonia severity in continuous speech: Application of a multi-parameter spectralcepstral model estimating dysphonia severity in continuous speech. Clinical Linguistics and Phonetics. 2009;23(11):825-841. doi:10.3109/02699200903242988.

    Time frame: Immediately after 3 minutes of exercise

Secondary outcomes

  1. Change in Baseline Sound Pressure Level (dB)

    Intensity of vocal signal

    Time frame: Immediately after 3 minutes of exercise

  2. Change in Baseline Mean Contact Quotient

    A percentage which illustrates the duration of vocal fold contact during one vocal fold period as measured by electroglottogram (EGG).

    Time frame: During 3 minutes of exercise (continual) and immediately following exercise.

  3. Change in Subglottic Pressure

    Measures of air pressure in the mouth.

    Time frame: During 3 minutes of exercise (continual)

  4. Transglottic Airflow

    Measures of flow of air through the vocal tract.

    Time frame: During 3 minutes of exercise (continual)

  5. Change in Baseline Laryngeal Resistance

    Derived from dividing mean intraoral pressure during /p/ by mean transglottic airflow during /a/ during a task which elicits repetition of 'pa-pa-pa-pa-pa'

    Time frame: Immediately after 3 minutes of exercise

  6. Change in Baseline Perceptual Voice Quality

    Expert ratings of overall voice quality using a simple ad-hoc 100mm visual analog scale (ranging from 0-100, reflecting a scale of normal voice quality to highly abnormal voice quality {higher numbers reflect more abnormality}).

    Time frame: Immediately after 3 minutes of exercise

  7. Change in Baseline Participant Self-ratings - Voice Quality

    Participant self-rating of voice quality (on a 100mm visual analog scale (0-100) where higher numbers reflect self-perception of better voice quality/ease of production)

    Time frame: Immediately after 3 minutes of exercise

06

Results

Posted Aug 1, 2023

Participant flow

Participant flow — Overall Study
MilestoneLow Laryngeal ResistanceHigh Laryngeal Resistance Group
Started1614
Acapella choice task1614
Tube-in-water task1614
Completed1614
Not completed00

Outcome measures

PrimaryChange in Baseline Cepstral/Spectral Index of Dysphonia (CSID)

A quantitative, multivariate, dysphonia summary tool that incorporates spectral (low/high spectral ratio) and cepstral measures (cepstral peak prominence), and their standard deviations, extracted from a continuous speech or sustained vowel sample utilising the software Analysis of Dysphonia in Speech and Voice (Kay Pentax, Montvale, NJ). The software calculates CSID on the scale of 0-100, whereby 0 represents no evidence of hoarse voice, and 100 represents a maximum amount of hoarseness. See: Awan SN, Roy N, Dromey C. Estimating dysphonia severity in continuous speech: Application of a multi-parameter spectralcepstral model estimating dysphonia severity in continuous speech. Clinical Linguistics and Phonetics. 2009;23(11):825-841. doi:10.3109/02699200903242988.

Time frame:
Immediately after 3 minutes of exercise
Reported as:
Mean · score on a scale
Change in Baseline Cepstral/Spectral Index of Dysphonia (CSID)
score on a scaleLow Laryngeal ResistanceHigh Laryngeal Resistance
Acapella Task1.22 ± 7.724.45 ± 12.2
WRT Task4.56 ± 13.13.13 ± 8.21
SecondaryChange in Baseline Sound Pressure Level (dB)

Intensity of vocal signal

Time frame:
Immediately after 3 minutes of exercise
Reported as:
Mean · dB
Change in Baseline Sound Pressure Level (dB)
dBLow Laryngeal ResistanceHigh Laryngeal Resistance
Acapella Task0.79 ± 1.971.46 ± 2.72
WRT Task1.57 ± 2.98-0.52 ± 2.76
SecondaryChange in Baseline Mean Contact Quotient

A percentage which illustrates the duration of vocal fold contact during one vocal fold period as measured by electroglottogram (EGG).

Time frame:
During 3 minutes of exercise (continual) and immediately following exercise.
Reported as:
Mean · percentage of contact
Change in Baseline Mean Contact Quotient
percentage of contactLow Laryngeal ResistanceHigh Laryngeal Resistance
Acapella Task0.01 ± 0.04-0.01 ± 0.06
WRT Task0.01 ± 0.060.00 ± 0.03
SecondaryChange in Subglottic Pressure

Measures of air pressure in the mouth.

Time frame:
During 3 minutes of exercise (continual)
Reported as:
Mean · cmH2O
Change in Subglottic Pressure
cmH2OLow Laryngeal ResistanceHigh Laryngeal Resistance
Acapella Task0.16 ± 1.720.95 ± 1.81
WRT Task-0.74 ± 0.61-0.68 ± 1.77
SecondaryTransglottic Airflow

Measures of flow of air through the vocal tract.

Time frame:
During 3 minutes of exercise (continual)
Reported as:
Mean · l/s
Transglottic Airflow
l/sLow Laryngeal ResistanceHigh Laryngeal Resistance
Acapella Task0.017 ± 0.1630.023 ± 0.075
WRT Task-0.011 ± 0.097-0.003 ± 0.061
SecondaryChange in Baseline Laryngeal Resistance

Derived from dividing mean intraoral pressure during /p/ by mean transglottic airflow during /a/ during a task which elicits repetition of 'pa-pa-pa-pa-pa'

Time frame:
Immediately after 3 minutes of exercise
Reported as:
Mean · cmH20/l/s
Change in Baseline Laryngeal Resistance
cmH20/l/sLow Laryngeal ResistanceHigh Laryngeal Resistance
Acapella Task1.40 ± 23.9-6.01 ± 58.7
WRT Task-5.04 ± 14.523.77 ± 122
SecondaryChange in Baseline Perceptual Voice Quality

Expert ratings of overall voice quality using a simple ad-hoc 100mm visual analog scale (ranging from 0-100, reflecting a scale of normal voice quality to highly abnormal voice quality {higher numbers reflect more abnormality}).

Time frame:
Immediately after 3 minutes of exercise
Reported as:
Mean · units on a scale
Change in Baseline Perceptual Voice Quality
units on a scaleLow Laryngeal ResistanceHigh Laryngeal Resistance
Acapella Task-1.82 ± 6.030.175 ± 4.73
WRT Task0.622 ± 4.655.18 ± 4.92
SecondaryChange in Baseline Participant Self-ratings - Voice Quality

Participant self-rating of voice quality (on a 100mm visual analog scale (0-100) where higher numbers reflect self-perception of better voice quality/ease of production)

Time frame:
Immediately after 3 minutes of exercise
Reported as:
Mean · units on a scale
Change in Baseline Participant Self-ratings - Voice Quality
units on a scaleLow Laryngeal ResistanceHigh Laryngeal Resistance
Acapella Task12.3 ± 13.84.62 ± 9.05
WRT Task6.56 ± 11.11.38 ± 9.97

Adverse events

Collected over 1 week. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Low Laryngeal Resistance0/14 (0%)0/14 (0%)0/14 (0%)
High Laryngeal Resistance0/16 (0%)0/16 (0%)0/16 (0%)

Baseline characteristics

Recruitment was undertaken along the lines of laryngeal diagnosis (10 patients in each diagnosis category). However, as laryngeal diagnosis results in diverse behavioural responses, treatment is never determined by diagnosis, alone. To better understand how participants responded to treatment, they were stratified into meaningful functional categories (Low and High Laryngeal Resistance), as these better represent the physiological targets of voice therapy.

Age, Categorical
Age, Categorical(Participants)Low Laryngeal ResistanceHigh Laryngeal ResistanceTotal
<=18 years000
Between 18 and 65 years10717
>=65 years6713
Age, Continuous
Age, Continuous(years)Low Laryngeal ResistanceHigh Laryngeal ResistanceTotal
Mean52.31 ± 16.858.14 ± 18.955.0 ± 17.8
Sex: Female, Male
Sex: Female, Male(Participants)Low Laryngeal ResistanceHigh Laryngeal ResistanceTotal
Female8816
Male8614
Race and Ethnicity Not Collected
Race and Ethnicity Not Collected(Participants)Low Laryngeal ResistanceHigh Laryngeal ResistanceTotal
Count of participants——0
Region of Enrollment
Region of Enrollment(participants)Low Laryngeal ResistanceHigh Laryngeal ResistanceTotal
United Kingdom161430
Aerodynamic Resistance (Z-score)
Aerodynamic Resistance (Z-score)(Z scores)Low Laryngeal ResistanceHigh Laryngeal ResistanceTotal
Median-0.63 (-1.09 to -0.18)1.07 (-0.16 to 2.30)-0.21 (-0.81 to 0.39)
07

Study locations

1 site
  • Royal National ENT Hospital, UCLH Hospitals NHS Trust
    London, NW1 2PG, United Kingdom
08

References and documents

Publications

  • Titze IR, Story BH. Acoustic interactions of the voice source with the lower vocal tract. J Acoust Soc Am. 1997 Apr;101(4):2234-43. doi: 10.1121/1.418246. PubMed 9104025 ↗
  • Titze IR. Voice training and therapy with a semi-occluded vocal tract: rationale and scientific underpinnings. J Speech Lang Hear Res. 2006 Apr;49(2):448-59. doi: 10.1044/1092-4388(2006/035). PubMed 16671856 ↗
  • Sovijärvi A. Die Bestimmung der Stimmkategorien mittels Resonanzröhren. [Voice classification according to resonance tubes]. In: Fifth International Congress of Phonetic Sciences. Basel, NY. ; 1965.
  • Simberg S, Laine A. The resonance tube method in voice therapy: description and practical implementations. Logoped Phoniatr Vocol. 2007;32(4):165-70. doi: 10.1080/14015430701207790. PubMed 17852715 ↗
  • Enflo L, Sundberg J, Romedahl C, McAllister A. Effects on vocal fold collision and phonation threshold pressure of resonance tube phonation with tube end in water. J Speech Lang Hear Res. 2013 Oct;56(5):1530-8. doi: 10.1044/1092-4388(2013/12-0040). Epub 2013 Jul 9. PubMed 23838993 ↗
  • Granqvist S, Simberg S, Hertegard S, Holmqvist S, Larsson H, Lindestad PA, Sodersten M, Hammarberg B. Resonance tube phonation in water: High-speed imaging, electroglottographic and oral pressure observations of vocal fold vibrations--a pilot study. Logoped Phoniatr Vocol. 2015 Oct;40(3):113-21. doi: 10.3109/14015439.2014.913682. Epub 2014 May 28. PubMed 24865620 ↗
  • Wistbacka G, Sundberg J, Simberg S. Vertical laryngeal position and oral pressure variations during resonance tube phonation in water and in air. A pilot study. Logoped Phoniatr Vocol. 2016 Oct;41(3):117-23. doi: 10.3109/14015439.2015.1028101. Epub 2015 Jun 2. PubMed 26033381 ↗
  • Amarante Andrade P, Wistbacka G, Larsson H, Sodersten M, Hammarberg B, Simberg S, Svec JG, Granqvist S. The Flow and Pressure Relationships in Different Tubes Commonly Used for Semi-occluded Vocal Tract Exercises. J Voice. 2016 Jan;30(1):36-41. doi: 10.1016/j.jvoice.2015.02.004. Epub 2015 Apr 11. PubMed 25873546 ↗
  • Andrade PA, Wood G, Ratcliffe P, Epstein R, Pijper A, Svec JG. Electroglottographic study of seven semi-occluded exercises: LaxVox, straw, lip-trill, tongue-trill, humming, hand-over-mouth, and tongue-trill combined with hand-over-mouth. J Voice. 2014 Sep;28(5):589-95. doi: 10.1016/j.jvoice.2013.11.004. Epub 2014 Feb 20. PubMed 24560003 ↗
  • Guzman M, Castro C, Madrid S, Olavarria C, Leiva M, Munoz D, Jaramillo E, Laukkanen AM. Air Pressure and Contact Quotient Measures During Different Semioccluded Postures in Subjects With Different Voice Conditions. J Voice. 2016 Nov;30(6):759.e1-759.e10. doi: 10.1016/j.jvoice.2015.09.010. Epub 2016 Jun 13. PubMed 26526005 ↗
  • Radolf V, Laukkanen A, Horacek J, Liu D. In vivo measurements of air pressure, vocal folds vibration and acoustic characteristics of phonation into a straw and resonance tube used in vocal exercising. In: Proceedings of the 19th International Conference Engineering Mechanics, Czech Republic. ; 2013:478-483.
  • Awan SN, Gartner-Schmidt JL, Timmons LK, Gillespie AI. Effects of a Variably Occluded Face Mask on the Aerodynamic and Acoustic Characteristics of Connected Speech in Patients With and Without Voice Disorders. J Voice. 2019 Sep;33(5):809.e1-809.e10. doi: 10.1016/j.jvoice.2018.03.002. Epub 2018 Aug 3. PubMed 30082107 ↗
  • Guzman M, Calvache C, Romero L, Munoz D, Olavarria C, Madrid S, Leiva M, Bortnem C, Pino J. Do Different Semi-Occluded Voice Exercises Affect Vocal Fold Adduction Differently in Subjects Diagnosed with Hyperfunctional Dysphonia? Folia Phoniatr Logop. 2015;67(2):68-75. doi: 10.1159/000437353. Epub 2015 Sep 23. Erratum In: Folia Phoniatr Logop. 2015;67(2):75. Pino, J [added]. PubMed 26394210 ↗
  • Guzman M, Higueras D, Fincheira C, Munoz D, Guajardo C, Dowdall J. Immediate acoustic effects of straw phonation exercises in subjects with dysphonic voices. Logoped Phoniatr Vocol. 2013 Apr;38(1):35-45. doi: 10.3109/14015439.2012.731079. Epub 2013 Jan 28. PubMed 23350916 ↗
  • Guzman M, Laukkanen AM, Krupa P, Horacek J, Svec JG, Geneid A. Vocal tract and glottal function during and after vocal exercising with resonance tube and straw. J Voice. 2013 Jul;27(4):523.e19-34. doi: 10.1016/j.jvoice.2013.02.007. Epub 2013 May 15. PubMed 23683806 ↗
  • Gaskill CS, Erickson ML. The effect of a voiced lip trill on estimated glottal closed quotient. J Voice. 2008 Nov;22(6):634-43. doi: 10.1016/j.jvoice.2007.03.012. Epub 2007 Jun 15. PubMed 17574810 ↗
  • Gaskill CS, Quinney DM. The effect of resonance tubes on glottal contact quotient with and without task instruction: a comparison of trained and untrained voices. J Voice. 2012 May;26(3):e79-93. doi: 10.1016/j.jvoice.2011.03.003. Epub 2011 May 7. PubMed 21550779 ↗
  • Gaskill CS, Erickson ML. The effect of an artificially lengthened vocal tract on estimated glottal contact quotient in untrained male voices. J Voice. 2010 Jan;24(1):57-71. doi: 10.1016/j.jvoice.2008.05.004. Epub 2009 Jan 9. PubMed 19135851 ↗
  • Guzman M, Castro C, Testart A, Munoz D, Gerhard J. Laryngeal and pharyngeal activity during semioccluded vocal tract postures in subjects diagnosed with hyperfunctional dysphonia. J Voice. 2013 Nov;27(6):709-16. doi: 10.1016/j.jvoice.2013.05.007. Epub 2013 Sep 26. PubMed 24075912 ↗
  • Vampola T, Laukkanen AM, Horacek J, Svec JG. Vocal tract changes caused by phonation into a tube: a case study using computer tomography and finite-element modeling. J Acoust Soc Am. 2011 Jan;129(1):310-5. doi: 10.1121/1.3506347. PubMed 21303012 ↗
  • Patterson JE, Hewitt O, Kent L, Bradbury I, Elborn JS, Bradley JM. Acapella versus 'usual airway clearance' during acute exacerbation in bronchiectasis: a randomized crossover trial. Chron Respir Dis. 2007;4(2):67-74. doi: 10.1177/1479972306075483. PubMed 17621572 ↗
  • Mueller G, Bersch-Porada I, Koch-Borner S, Raab AM, Jonker M, Baumberger M, Michel F. Laboratory evaluation of four different devices for secretion mobilization: Acapella choice, green and blue versus water bottle. Respir Care. 2014 May;59(5):673-7. doi: 10.4187/respcare.02654. Epub 2013 Sep 17. PubMed 24046459 ↗

Study documents

  • Protocol and statistical analysis plan · Sep 15, 2020

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

09

Registry details

Key details

Study ID
NCT04764604
Lead sponsor
University College, London
Collaborators
Smiths Medical, ASD, Inc.
Responsible party
Sponsor
First posted
Feb 21, 2021
Start date
Dec 14, 2020
Primary completion
Nov 29, 2021
Completion
Nov 29, 2021
Results posted
Aug 1, 2023
Last update
Aug 1, 2023

Study contacts

Brian Saccente-Kennedy, MSc
principal investigator · University College London Hospitals

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
Yes
View the source record on ClinicalTrials.gov ↗

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