Primary Muscle Tension Dysphonia

Development and Psychometric Evaluation of the Laryngeal Palpation Pain Scale (LPPS)

INTRODUCTION

One of the most important assessment and therapy methods for patients with muscle tension dysphonia (MTD) and other voice disorders is laryngeal palpation. However, there is no comprehensive scale for measuring pain during laryngeal palpation. The goal of the present study was to develop and validate a new scale to evaluate pain during palpation for patients with MTD.

METHODS

The present study consisted of two phases: (1) Development of the Laryngeal Palpation Pain Scale (LPPS) based on an in-depth literature review, the palpatory evaluation of MTD patients, interviews with experts in the field of voice disorders, and consultation with a registered pain expert, and (2) evaluation of the validity and reliability of the LPPS. The validity of the LPPS was investigated using qualitative and quantitative content validity, qualitative face validity, discriminant validity, and convergent validity. Content validity of the LPPS was assessed by experts' opinions (10 speech-language pathologists and five laryngologists), and face validity was investigated using the opinions of speech-language pathologists. The reliability of the LPPS was determined using test-retest and inter-rater reliability.

RESULTS

The item generation phase of the study led to the development of a scale to assess pain during palpation that included eleven locations in the neck region for palpatory assessment. These 11 items were divided into 13 different items (neck locations) based on the opinions of the experts. The content validity ratio values of all scale items were higher than 0.78. The content validity index (CVI) value for each of the items of the scale was higher than 0.79 and for the entire scale CVI (S-CVI) was 0.915. The results of the reliability of the LPPS items were satisfactory with weighted kappa values ranging from 0.655 to 1 for the test-retest and 0.77-1 for the inter-rater reliability. Convergent validity of the LPPS was shown with a significant positive correlation (r = 0.68) between the LPPS and the pain severity of vocal tract discomfort (P < 0.001). Moreover, MTD patients had more pain severity than the control group in all items of the LPPS (P < 0.05) except for the submental item (P = 0.89). These results indicate that the LPPS can differentiate MTD patients from healthy subjects. The final version of the LPPS includes 13 potential pain locations. The severity of pain at each of these locations is determined on a numeric pain rating scale of zero (no pain) to ten (the most severe pain).

CONCLUSION

The study showed that the LPPS is a valid and reliable scale to assess pain in MTD patients during palpation evaluations. More studies are recommended for further psychometric evaluation of the LPPS including responsiveness to change (the use in before-and-after intervention studies) and concurrent validity of the LPPS. The LPPS can be used for clinical and research purposes.

Characterization of Primary Muscle Tension Dysphonia Using Acoustic and Aerodynamic Voice Metrics

OBJECTIVES/HYPOTHESIS

The objectives of this study were to (1) identify optimal clusters of 15 standard acoustic and aerodynamic voice metrics recommended by the American Speech-Language-Hearing Association (ASHA) to improve characterization of patients with primary muscle tension dysphonia (pMTD) and (2) identify combinations of these 15 metrics that could differentiate pMTD from other types of voice disorders.

STUDY DESIGN

Retrospective multiparametric METHODS: Random forest modeling, independent t-tests, logistic regression, and affinity propagation clustering were implemented on a retrospective dataset of 15 acoustic and aerodynamic metrics.

RESULTS

Ten percent of patients seen at the New York University (NYU) Voice Center over two years met the study criteria for pMTD (92 out of 983 patients), with 65 patients with pMTD and 701 of non-pMTD patients with complete data across all 15 acoustic and aerodynamic voice metrics. PCA plots and affinity propagation clustering demonstrated substantial overlap between the two groups on these parameters. The highest ranked parameters by level of importance with random forest models-(1) mean airflow during voicing (L/sec), (2) mean SPL during voicing (dB), (3) mean peak air pressure (cmH2O), (4) highest F0 (Hz), and (5) CPP mean vowel (dB)-accounted for only 65% of variance. T-tests showed three of these parameters-(1) CPP mean vowel (dB), (2) highest F0 (Hz), and (3) mean peak air pressure (cmH2O)-were statistically significant; however, the log2-fold change for each parameter was minimal.

CONCLUSION

Computational models and multivariate statistical testing on 15 acoustic and aerodynamic voice metrics were unable to adequately characterize pMTD and determine differences between the two groups (pMTD and non-pMTD). Further validation of these metrics is needed with voice elicitation tasks that target physiological challenges to the vocal system from baseline vocal acoustic and aerodynamic ouput. Future work should also place greater focus on validating metrics of physiological correlates (eg, neuromuscular processes, laryngeal-respiratory kinematics) across the vocal subsystems over traditional vocal output measures (eg, acoustics, aerodynamics) for patients with pMTD.

LEVEL OF EVIDENCE

II.

A mixed-method feasibility study of the use of the Complete Vocal Technique (CVT), a pedagogic method to improve the voice and vocal function in singers and actors, in the treatment of patients with muscle tension dysphonia: a study protocol

BACKGROUND

Muscle tension dysphonia (MTD) results from inefficient or ineffective voice production and is the cause of voice and throat complaints in up to 40% of patients presenting with hoarseness. Standard treatment is voice therapy (SLT-VT) delivered by specialist speech therapists in voice disorders (SLT-V). The Complete Vocal Technique (CVT) is a structured, pedagogic method which helps healthy singers and other performers optimise their vocal function enabling them to produce any sound required. The aim of this feasibility study is to investigate whether CVT administered by a trained, non-clinical CVT practitioner (CVT-P) can be applied to patients with MTD before progressing to a pilot randomised control study of CVT voice therapy (CVT-VT) versus SLT-VT.

METHODS/DESIGN

In this feasibility study, we use a mixed-method, single-arm, prospective cohort design. The primary aim is to demonstrate whether CVT-VT can improve the voice and vocal function in patients with MTD in a pilot study using multidimensional assessment methods. Secondary aims are to assess whether (1) a CVT-VT study is feasible to perform; (2) is acceptable to patients, the CVT-P and SLT-VTs; and (3) whether CVT-VT differs from existing SLT-VT techniques. A minimum of 10 consecutive patients with a clinical diagnosis of primary MTD (types I-III) will be recruited over a 6-month period. Up to 6 video sessions of CVT-VT will be delivered by a CVT-P using a video link. The primary outcome will be a change in pre-/post-therapy scores of a self-reported patient questionnaire (Voice Handicap Index (VHI)). Secondary outcomes include changes in throat symptoms (Vocal Tract Discomfort Scale), acoustic/electroglottographic and auditory-perceptual measures of voice. Acceptability of the CVT-VT will be assessed prospectively, concurrently and retrospectively both quantitatively and qualitatively. Differences from SLT-VT will be assessed by performing a deductive thematic analysis of CVT-P transcripts of therapy sessions.

CONCLUSION

This feasibility study will provide important data to support whether to proceed with a randomised controlled pilot study focusing on the effectiveness of the intervention compared to standard SLT-VT. Progression criteria will be based on demonstrating a positive outcome in treatment, successful delivery of the pilot study protocol, acceptability to all stakeholders and satisfactory recruitment rates.

TRIAL REGISTRATION

ClinicalTrials.gov website ( NCT05365126 Unique Protocol ID: 19ET004). Registered on 06 May 2022.

Methods of Measuring Laryngeal Muscle Tension in Patients with Muscle Tension Dysphonia: A Scoping Review

BACKGROUND

In clinical practice and research relating to Muscle Tension Dysphonia (MTD), several laryngeal muscle tension measurement methods are used to diagnose, to identify specific muscle strengths and deficits, and to measure therapeutic outcomes. The variety and reliability of available measurement methods presents challenges within diagnosis and treatment. The lack of methodical standardization presents a barrier to homogeneous practice in this area. There is a need for a comprehensive scoping review of laryngeal muscle tension measurement methods.

STUDY DESIGN

Scoping review.

OBJECTIVES

(1) To identify current methods of laryngeal muscle measurement which have been developed or tested with people with MTD; and (2) To identify the construct/s measured, reliability, validity, ability to detect change, efficiency and accessibility of identified methods.

METHOD

This scoping review was conducted using the Arksey and O'Malley framework. Studies were identified through searches of 4 major databases. The reviewer independently assessed titles, abstracts, and full-text articles.

RESULTS

Twenty seven papers published from 2000 to 2022 that satisfied the inclusion criteria were selected from 194 studies. The papers showed a variety of approaches with regards to the measurement of laryngeal activity and tension in subjects with MTD. Just over a quarter (25.9%) were reviews of the validity of assessment methods of MTD, including surface electromyography (sEMG), while 22.2% discussed surface electromyography as a measurement of muscle activity in subjects with MTD. 96.3% used a published methodological framework.

CONCLUSIONS

Assessment methods for Primary MTD are multifaceted, including patient history, laryngoscopic examination, and voice-related musculoskeletal features. Potential use of objective measurement methods, including sEMG, Real Time Elastosonography, Magnetic Resonance Imaging was noted. Due to variability in assessment methods and results, there is a need for greater objective practical methodological standardization to ensure accurate diagnosis, appropriate care, and chart patient progress.

Immediate Effects of Combining Kinesio Tape with Voice Therapy in Patients with Muscle Tension Dysphonia

INTRODUCTION

The present study investigated the immediate effect of adding Kinesio taping along with voice therapy for the treatment of muscle tension dysphonia patients.

MATERIALS AND METHODS

Twenty patients with primary muscle tension dysphonia (MTD) (12 males and 8 females) with a mean age of 36.95 ± 9.58 years participated in the study. Participants were assigned to two groups: one group (6 males and 4 females) received only traditional voice therapy (VT) and the other group (6 males and 4 females) received Kinesio taping (KT) and voice therapy (VT). The VT group received laryngeal manual therapy (LMT) (for 15 minutes) and voice therapy techniques including humming, chewing, and yawn-sigh (for 15 minutes). The VT + KT group received both KT and the same VT as the first group. KT was applied to the sternocleidomastoid, infralaryngeal, and supralaryngeal muscles of the neck. Auditory-perceptual assessments using CAPE-V, acoustic voice analysis, and assessments of vocal tract discomfort and pain were used to evaluate the effects of a single treatment session. The Wilcoxon and Mann-Whitney U tests were used for data analysis.

RESULTS

The results of within-group comparison of the auditory-perceptual assessment (overall severity, roughness, breathiness, and strain) in both sustained vowels and connected speech tasks showed a significant reduction in all mentioned items in both groups (P < 0.05). Acoustic voice analysis showed significant improvement of HNR in the KT + VT group for both sustained vowels and connected speech tasks, and significant improvement of jitter in the VT group for sustained vowels (P < 0.05). Regarding vocal tract discomfort, the symptom of tightness in the KT + VT group, irritability and pain in the VT group, and the overall score of vocal tract discomfort in both groups, significantly decreased (P < 0.05). A significant decrease in pain severity in the front of the neck, throat, and larynx was reported by MTD patients in both groups (P < 0.05). Between-group comparisons indicated a significant difference only in the pain item of the VTD scale (P < 0.05) with greater pain decrease for the VT group. Comparison of the mean of differences showed that the VT group reduced irritability more than the KT + VT group (P < 0.05).

CONCLUSION

The present study showed that voice therapy with and without Kinesio taping can improve patients' voice quality (auditory-perceptual and acoustic voice analysis) and reduce vocal tract discomfort and pain in MTD patients after one therapy session. Moreover, MTD patients treated with KT + VT did not experience more significant improvements compared to those treated with VT alone. More studies in this area are recommended to better determine the effects of KT in MTD patients especially for long term effects of KT.

Effect of Electrical Stimulation on the Treatment of Dysphonia: A Systematic Review

OBJECTIVES

The aim of this study was to review systematically the literature and to investigate the effects of electrical stimulation in treating dysphonia.

STUDY DESIGN

This is a systematic review.

METHODS

The publications indexed on the MEDLINE, LILACS, PubMed, Web of Science, and SciELO databases were searched. Original articles with experimental, clinical trial and randomized studies involving a control group and approaching dysphonia treatment with electrical stimulation in humans, regardless of age, gender, or race were included. Those excluded were theses, editorials, comments and opinions, reflexive articles, case studies, experimental studies with animals, models, projects, reports and technical reports, and review articles, as well as articles approaching other alterations, not related to dysphonia.

RESULTS

Eleven articles were found and it evaluated the effects of neuromuscular electrical stimulation (NMES) and transcutaneous electrical nerve stimulation on dysphonia caused by vocal fold paralysis, spasmodic dysphonia, behavioral dysphonia, and in patients with vocal fold nodules. The methodological analysis of the articles through the PEDro scale resulted in a mean score of 5.18; the studies were classified as either high quality (N = 3) or fair quality (N = 8). The results indicated that electrical stimulation had a therapeutic effect on various aspects of dysphonia. However, due to the high risk of bias and the heterogeneity of the studies, it is not possible to state the effectiveness of electrical stimulation in treating dysphonia.

CONCLUSION

Using electrical stimulation as an evidence-based conventional rehabilitation therapy in the treatment of dysphonia cannot yet be done.

Patient-Reported Factors Associated with the Onset of Hyperfunctional Voice Disorders

OBJECTIVES

Prevention, diagnosis, and treatment of hyperfunctional voice disorders would be improved by better understanding their etiological contributing factors. Therefore, this study estimated the prevalence of etiological factors using self-reported data about disorder onset from a large cohort of patients with Phonotraumatic Vocal Hyperfunction (PVH) and Non-Phonotraumatic Vocal Hyperfunction (NPVH).

METHODS

Retrospective chart review extracted the self-reported rate (gradual, sudden) and events associated (voice use, anxiety/stress, upper respiratory infection [URI]) with disorder onset from 1,577 patients with PVH and 979 patients with NPVH.

RESULTS

Both patient groups reported a gradual onset more than a sudden onset. Voice use was the most frequently reported event for PVH and the NPVH group self-reported all three events at equal frequency. The largest PVH subgroups were associated with voice use while the NPVH subgroups were associated with only voice use, only URI, or only anxiety/stress.

CONCLUSION

The results support the general clinical view that PVH is most strongly related to the gradual accumulated effects of phonotrauma, while NPVH has a more heterogeneous etiology. The identified PVH and NPVH subgroups may have clinical relevance and future work could investigate differences in treatment and outcomes among these subgroups.

Do Phonatory Aerodynamic and Acoustic Measures in Connected Speech Differ Between Vocally Healthy Adults and Patients Diagnosed with Muscle Tension Dysphonia?

OBJECTIVES

One of the presumed etiologies of primary muscle tension dysphonia (MTD) is a respiratory-phonatory disruption resulting in poor phonatory airflow in speech; however, few data exist on the differences between vocally healthy adults and patients diagnosed with MTD. The goal of this study was to compare aerodynamic and acoustic measures of self-perceived vocally healthy adults with patients diagnosed with MTD.

STUDY DESIGN

Retrospective, observational, matched cohort study.

METHODS

Vocally healthy adults age 19-60 years were matched on age, gender, and body mass index (BMI) to patients diagnosed with MTD. Recorded samples of the first four sentences of The Rainbow Passage were analyzed for between-group differences in the following acoustic and aerodynamic dependent measures in connected speech: mean airflow during voicing, breath number, reading passage duration, inspiratory and expiratory durations, phonation time, inspiratory and expiratory volumes, cepstral peak prominence (CPP), CPP standard deviation (CPP SD), low to high ratio (L/H ratio), L/H ratio SD, CPP Fo, CPP Fo SD, cepstral spectral index of dysphonia, and dB sound pressure level (SPL).

RESULTS

One hundred and seventy participants were studied; 85 patients diagnosed with primary MTD and 85 vocally healthy control participants. The two groups differed significantly in mean SPL, duration of the reading passage, and inspiratory and expiratory airflow duration (P ≤ 0.003). No significant differences were observed between the groups on any other phonatory aerodynamic or acoustic measure. Mean SPL, duration of the reading passage, and inspiratory and expiratory airflow durations were lower and longer, respectively, in patients with MTD. Ranges and standard deviations were greater for all aerodynamic and acoustic measurements in patients with MTD.

CONCLUSION

Large variability in aerodynamic and acoustic measurements were observed in patients with primary MTD with no salient differences at the group level compared to vocally healthy participants. Individual phonatory aerodynamic and acoustic profiles should be used when setting goals for patient treatment plans and to track response to treatment for patients with MTD. Taken in its entirety, connected speech from patients diagnosed with MTD essentially reflect normal acoustic and aerodynamic values.