MyotonPRO as a new valid tool for measuring cervical muscle tension. A reliability study.

OBJECTIVE: The main objective of this study is to test the reliability of a non-invasive objective method for the measurement of biomechanical parameters of cervicofacial muscle groups, with the purpose of diagnosis and evaluation of voice disorders' treatments, especially focused on muscle tension dysphonia. STUDY DESIGN: Prospective study. METHODS: The device used is a handheld myotonometer (MyotonPRO) that measures biomechanical and viscoelastic properties in superficial soft tissues frequency, stiffness, elasticity, relaxation time and creep. It is used in the field of medicine, sport and research. This pilot study includes 10 subjects, who have been measured in the masseter, sternocleidomastoid, orbicularis oris, semispinalis capitis, suprahyoid, infrahyoid and trapezius muscles on each side. Measurements were performed by 2 evaluators to assess inter-evaluator reliability. Subsequently, one of them repeated the measurements to assess intra-evaluator reliability. RESULTS: The results revealed good to excellent inter-rater reliability for the masseter, sternocleidomastoid, trapezius and suprahyoid muscles, with lower ICCs for the stiffness and creep properties. Intra-rater reliability was good to excellent for the masseter, sternocleidomastoid, semispinalis capitis and suprahyoid muscles. The lowest ICCs were found in the stiffness and creep properties. CONCLUSION: The use of a myotonometer to measure the mechanical properties of selected cervical and orofacial muscles is a reliable and reproducible method. Future research is needed to establish an association between the properties of these muscles and their role in voice disorders, as well as to determine whether this tool can aid diagnosis with quantifiable and objectifiable indicators, and for monitoring and treatment efficacy.

Relative Fundamental Frequency: Only for Hyperfunctional Voices? A Pilot Study.

(1) Background: Assessing phonatory disorders due to laryngeal biomechanical alterations requires aerodynamic analysis, assessing subglottic pressure, transglottic flow, and laryngeal resistance. This study explores whether the acoustic parameter, the relative fundamental frequency (RFF), can be studied using the current acoustic analysis protocol at the University of Navarra's voice laboratory and its association with pathologies linked to laryngeal biomechanical alterations. (2) Methods: A retrospective cohort study included patients diagnosed with muscular tension dysphonia, organic lesions of the vocal fold, and vocal fold paralysis (VFP) at the Clínica Universidad de Navarra from 2019 to 2021. Each patient underwent endoscopic laryngeal exploration, followed by acoustic study, RFF calculation, and an aerodynamic study. Additionally, a control group was recruited. (3) Results: 79 patients and 22 controls were studied. Two-way ANOVA showed significant effects for groups and cycles in offset and onset cycles. Statistically significant differences were observed in cycle 1 onset among all groups and in cycles 1 and 2 between the control group and non-healthy groups. (4) Conclusions: RFF is a valuable indicator of phonatory biomechanics, distinguishing healthy and pathological voices and different disorders. RFF in onset cycles offers a cost-effective, accurate method for assessing biomechanical disorders without complex aerodynamic analyses. This study describes RFF values in VFP for the first time, revealing differences regardless of aerodynamic patterns.

Clinical Characteristics of Individuals Presenting to Physiotherapy for Voice and Throat Care: A Retrospective Case Notes Review.

BACKGROUND: Currently, little is known about the characteristics of individuals presenting for physiotherapy care with voice and throat problems. PURPOSE: The aim of this study is to describe the demographic and clinical characteristics of individuals presenting to physiotherapy for voice and throat-related problems, and to use this information to clarify the role of physiotherapy in the management of people with voice and throat problems. METHODS: A retrospective clinical case notes review was conducted of all clients who accessed physiotherapy for voice and throat problems at a private practice based in Christchurch within a 12-month period from 1st October 2020 to 1st October 2021. RESULTS: Data were analyzed from 53 patient charts. The typical profile of an individual accessing physiotherapy for voice and throat problems were female (n = 37), NZ European (n = 26), singer (n = 43), with chronic problems (n = 20), of a nontraumatic origin (n = 45). Voice problems were present in 39 cases and muscle-related problems were present in 42 cases. Treatment primarily included manual therapy and various modes of exercise therapy. CONCLUSIONS: The clinical characteristics described offer insight into the demographic and clinical characteristics of individuals accessing physiotherapy services for voice and throat problems. A high prevalence of muscle-related problems and wider issues were identified, consistent with the physiotherapy skill set. Physiotherapy appears to complement existing ENT or SLT services by identifying and managing muscle-related voice problems and addressing wider factors contributing to voice and throat problems.

A Conceptual Framework and Treatment Taxonomy for Respiratory Lung Volume Training (RLVT).

OBJECTIVES: The purpose of this study was to describe the theoretical and procedural framework of a novel intervention, Respiratory Lung Volume Training (RLVT), and to implement a standardized treatment taxonomy to operationalize the RLVT treatment paradigm. STUDY DESIGN: This study involved a prospective design with a consensus treatment classification process. METHODS: The RLVT paradigm was developed based on biomechanical constructs governing the interactions of the respiratory and phonatory systems in voice production and principles of motor learning theory. In RLVT, higher levels of lung volume (LV) during speech are trained using multiple speech breathing strategies while providing real-time visual biofeedback with superimposed guidelines for desired LV initiation and termination levels. For people with primary muscle tension dysphonia (MTD), RLVT can capitalize on nonmuscular respiratory forces to increase efficiency of voice production with reduced speaking effort. To define and operationalize the treatment components of RLVT, six investigators with training in RLVT used the Rehabilitation Treatment Specification System to delineate the treatment targets, mechanisms of action, ingredients and dosing through a multistage, consensus decision-making process. RESULTS: The finalized taxonomy for RLVT included four treatment targets, with three addressing the area of Respiratory Function and one addressing Somatosensory Function. For each treatment target, three categories of ingredients were defined: (1) provide opportunities to practice breathing during voicing/speech, (2) provide feedback, and (3) provide volition ingredients. Within each ingredient category, three to seven specific ingredients were ultimately defined to further operationalize RLVT. CONCLUSIONS: The RLVT paradigm is a theoretically driven approach for optimizing speech breathing patterns to increase efficient voice production in people with primary MTD. By applying a standardized, systematic treatment taxonomy system to specify the components of RLVT, future researchers and clinicians can implement RLVT with improved fidelity and consistency to optimize treatment outcomes.

Vocal Effort and Acoustic Analysis of Gargle Phonation Versus Water Swallow in Patients With Muscle Tension Dysphonia: A Clinical Trial.

PURPOSE: To determine the effects of gargle phonation (GP) on self-perceived vocal improvement, vocal effort, acoustic parameters, and speech rate in patients with muscle tension dysphonia (MTD). We hypothesized that GP would improve voice, reduce phonatory effort, and alter acoustic and speech measures. STUDY DESIGN: Prospective randomized, single-blind cross-over clinical trial METHODS: Thirty-four participants (26 females, 8 males; average age 53 years) who were diagnosed with MTD completed the Voice Handicap Index-10 (VHI-10) and were assigned three study conditions: Baseline (B), GP, and Water Swallow (WS; sham), presented in one of two counterbalanced orders B-WS-GP (WS1st) or B-GP-WS (GP1st). Participants recorded stimuli from the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) and rated their perceived vocal effort and vocal improvement. F0, vocal intensity, cepstral peak prominence (CPP), and speaking rate were measured. RESULTS: Average VHI-10 scores by group were 16 (min/max 2-29) for WS1st and 15 (min/max 3-40) for GP1st. About 73.5% reported more vocal improvement after GP, 17.65% after WS, and 8.8% noted no difference between conditions. Reduced effort was reported after GP, compared to B (P < 0.001) and WS (P = 0.005). Lower effort was also reported after the WS condition, compared to B (P = 0.011). Key acoustic findings included an increase in F0 after GP for sustained /i/ for females. CPP was significantly higher for females reading CAPE-V sentences after GP, when GP preceded WS, compared to B (P = 0.004) and WS (P = 0.003). Speech rate was faster for females after GP versus B (P = 0.029). CONCLUSIONS: GP may be beneficial in the treatment of MTD. CPP may be a useful marker for vocal improvement after GP for women with mild MTD. Further studies would benefit from having more male participants and those with moderate and severe MTD.

Relationships Between Vocal Fold Adduction Patterns, Vocal Acoustic Quality, and Vocal Effort in Individuals With and Without Hyperfunctional Voice Disorders.

OBJECTIVES/HYPOTHESIS: Increased vocal effort and aberrant vocal quality are often attributed to vocal fold hyperadduction in hyperfunctional voice disorders. However, there are currently no established methods to quantify vocal fold adduction beyond subjective descriptors in this clinical population. Furthermore, relationships between vocal fold adduction patterns, vocal effort severity, and vocal quality are not well characterized. Therefore, the objectives of this study were to (1) quantify vocal fold adduction, applying a previously validated method developed for patients with vocal fold paralysis, and (2) correlate these measures with acoustic vocal quality and self-perceived measures of vocal effort severity. METHODS: A deep learning program, Automated Glottic Action Tracking using artificial Intelligence, was used to track glottic angle configurations and vocal fold adduction velocities on laryngoscopic videos across 60 laryngoscopies (20 primary muscle tension dysphonia [pMTD], 20 phonotraumatic lesions, and 20 healthy controls). Voice samples were also acquired, and cepstral peak prominence (CPP) and H1-H2 acoustic measures were used to quantify vocal quality. Participants were also asked to rate their vocal effort on a 100 mm visual analog scale. RESULTS: There were no significant group differences in glottic angle configurations or vocal fold adduction velocities, although there were trends toward increased peak vocal fold adduction velocities in patients with hyperfunctional voice disorders compared to controls. Vocal effort was significantly higher in the two hyperfunctional groups compared to controls. CPP was significantly lower in the pMTD group, but there were no group differences in acoustic parameters between any of the other groups or for H1-H2 values. CONCLUSION: Despite significantly more vocal effort reported in patients with hyperfunctional voice disorders, there were no significant group differences in vocal fold adduction patterns. These findings suggest other physiologic mechanisms may also be responsible for the symptoms and genesis of pMTD and benign vocal fold lesions.

The Efficacy of the Manual Circumlaryngeal Therapy for Muscle Tension Dysphonia: A Systematic Review and Meta-analysis.

OBJECTIVE: Muscle tension dysphonia (MTD) is the most common functional voice disorder. Behavioral voice therapy is the front-line treatment for MTD, and laryngeal manual therapy may be a part of this treatment. The objective of this study was to investigate the effect of manual circumlaryngeal therapy (MCT) on acoustic markers of voice quality (jitter, shimmer, and harmonics-to-noise ratio) and vocal function (fundamental frequency) through a systematic review with meta-analysis. DATA SOURCES: Four databases were searched from inception to December 2022, and a manual search was performed. REVIEW METHODS: The PRISMA extension statement for reporting systematic reviews incorporating a meta-analysis of health care interventions was applied, and a random effects model was used for the meta-analyses. RESULTS: We identified 6 eligible studies from 30 studies (without duplicates). The MCT approach was highly effective on acoustics with large effect sizes (Cohen's d > 0.8). Significant improvements were obtained in jitter in percent (mean difference of -.58; 95% CI -1.00 to 0.16), shimmer in percent (mean difference of -5.66; 95% CI -8.16 to 3.17), and harmonics-to-noise ratio in dB (mean difference of 4.65; 95% CI 1.90-7.41), with the latter two measurements continuing to be significantly improved by MCT when measurement variability is considered. CONCLUSION: The efficacy of MCT for MTD was confirmed in most clinical studies by assessing jitter, shimmer, and harmonics-to-noise ratio related to voice quality. The effects of MCT on the fundamental frequency changes could not be verified. Further contributions of high-quality randomized control trials are needed to support evidence-based practice in laryngology. Laryngoscope, 134:18-26, 2024.

Laryngological Symptomatology in Patients with Ehlers-Danlos Syndrome.

Laryngological manifestations of connective tissue diease with hypermobility such as ehlers-danlos syndrome (EDS) are not well defined in the literature. EDS is an inherited, hetrogeneous, connective tissue disorder characterized by joint hypermobility, skin extensibility, and joint dislocations. A case series of 9 patients is presented with varying laryngological complaints. Common comorbities include postural orthostatic tachycardia syndrome (POTS), fibromyalgia, irritable bowel syndrome (IBS), and gastroesophageal reflux disease (GERD)/laryngopharyngeal reflux disease (LPRD). Six patients were singers. Videostroboscopic parameters and treatment courses are described. It may be beneficial to view patients with EDS and laryngological complaints through a holistic lens as many may need interdisciplinary assessment and management. Laryngoscope, 134:894-896, 2024.

Optical Flow Analysis of Paralaryngeal Muscle Movement.

OBJECTIVES: The paralaryngeal muscles are thought to be hyperfunctional with phonation in patients with primary muscle tension dysphonia (pMTD). However, objective, quantitative tools to assess paralaryngeal movement patterns lack. The objectives of this study were to (1) validate the use of optical flow to characterize paralaryngeal movement patterns with phonation, (2) characterize phonatory optical flow velocities and variability of the paralaryngeal muscles before and after a vocal load challenge, and (3) compare phonatory optical flow measures to standard laryngoscopic, acoustic, and self-perceptual assessments. METHODS: Phonatory movement velocities and variability of the paralaryngeal muscles at vocal onsets and offsets were quantified from ultrasound videos and optical flow methods across 42 subjects with and without a diagnosis of pMTD, before and after a vocal load challenge. Severity of laryngoscopic mediolateral supraglottic compression, acoustic perturbation, and ratings of vocal effort and discomfort were also obtained at both time points. RESULTS: There were no significant differences in optical flow measures of the paralaryngeal muscles with phonation between patients with pMTD and controls. Patients with pMTD had significantly more supraglottic compression, higher acoustic perturbations, and higher vocal effort and vocal tract discomfort ratings. Vocal load had a significant effect on vocal effort and discomfort but not on supraglottic compression, acoustics, or optical flow measures of the paralaryngeal muscles. CONCLUSION: Optical flow methods can be used to study paralaryngeal muscle movement velocity and variability patterns during vocal productions, although the role of the paralaryngeal in pMTD diagnostics (e.g., vocal hyperfunction) remains suspect. LEVEL OF EVIDENCE: 2 Laryngoscope, 134:1792-1801, 2024.

The Impact of Foreign Language Accent on Expert Listeners' Auditory-Perceptual Evaluations of Dysphonia.

INTRODUCTION: Auditory-perceptual evaluations of dysphonia, though essential for comprehensive voice evaluation, are subject to listener bias. Knowledge of an underlying voice disorder can influence auditory-perceptual ratings. Accented speech results in increased listener effort and delays in word identification. Yet, little is known about the impact of foreign language accents on auditory-perceptual ratings for dysphonic speakers. The purpose of this work was to determine the impact of a foreign language accent on experts' auditory-perceptual ratings of dysphonic speakers. METHODS: Twelve voice-specializing SLPs who spoke with a General American English (GAE) accent rated vocal percepts of 28 speakers with a foreign language accent and 28 with a GAE accent, all of whom had been diagnosed with a voice disorder. Speaker groups were matched based on sex, age, and mean smoothed cepstral peak prominence. Four linear mixed-effects models assessed the impact of a foreign language accent on expert auditory-perceptual ratings of the overall severity of dysphonia, roughness, breathiness, and strain. RESULTS: The twelve raters demonstrated good inter- and intra-rater reliability (ICC[3, k] = .89; mean ICC = .89). The linear mixed-effects models revealed no significant impact of foreign language accent on ratings of overall severity of dysphonia, roughness, breathiness, or strain. CONCLUSION: Despite the possibility of increased listener effort and bias, foreign language accent incongruence had no effect on expert listeners' auditory-perceptual evaluations for dysphonic speakers. Findings support the use of auditory-perceptual evaluations for voice disorders across sociolinguistically diverse populations. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:2272-2276, 2024.

Indications and Short-Term Outcomes for In-Office Therapeutic Superior Laryngeal Nerve Block.

OBJECTIVE: Superior laryngeal nerve (SLN) block consists of injection of steroid and anesthetic at the internal branch of the SLN entry site. Prior case series have demonstrated beneficial effects on neurogenic cough. SLN blocks have also recently shown benefit for paralaryngeal pain. We describe short-term outcomes for multiple symptoms of irritable larynx syndrome (ILS) including neurogenic cough, dysphonia related to laryngeal hypersensitivity, inducible laryngeal obstruction (ILO), paralaryngeal pain, and isolated globus. METHODS: Retrospective review from 2 institutions of patients undergoing a single SLN block for the indications listed. Variables include age, sex, indication(s), known vagus neuropathy, and patient-reported outcomes at short-term follow-up. RESULTS: A total of 209 patients were included (59 males, 150 females; age: 58 ± 13 years). Twenty-six patients (12%) had a history of a vagus nerve injury. Indications included neurogenic cough (n = 149), dysphonia related to laryngeal hypersensitivity (n = 66), paralaryngeal pain (n = 50), ILO (n = 23), and isolated globus (n = 3). Some patients had multiple indications. Significant improvements in patient-reported measures occurred after a single SLN block within 2 to 4 weeks for neurogenic cough (cough severity index; 25.2 ± 11.2 to 19.0 ± 12.8; P < .001), dysphonia (voice handicap index-10; 22.1 ± 12.2-18.0 ± 13.3; P = .005), and ILO (dyspnea index; 21.0 ± 14.9-14.7 ± 15.7; P = .017). Subjective pain improved in 23 of 39 patients with paralaryngeal pain. There was no observed improvement for isolated globus. Presence of known vagal neuropathy or therapy around the time of SLN block did not affect outcome. CONCLUSION: SLN block can be an effective component of treatment for a variety of ILS symptoms. Patients may experience some improvement after 1 injection. LAY SUMMARY: Symptoms of irritable larynx syndrome, such as neurogenic cough, paralaryngeal pain, inducible laryngeal obstruction, and dysphonia related to laryngeal hypersensitivity can be challenging to manage. In-office Superior Laryngeal Nerve blocks can serve as a quick, well tolerated, adjunctive treatment with positive short-term outcomes. LEVEL OF EVIDENCE: 4.

The Effect of Adding Cricothyroid Visor Maneuver to Voice Facilitating Techniques on Improving Voice in Individuals With Primary Muscle Tension Dysphonia: A Pilot Randomized Clinical Trial.

OBJECTIVES: The purpose of the present study was to examine the effect of adding a cricothyroid visor maneuver to conventional voice-facilitating techniques on voice quality and reported symptoms in patients with primary muscle tension dysphonia. METHODS: This was a double-blind two parallel-group clinical trial in which 20 adult patients participated through convenience sampling. Participants were allocated to intervention (combined treatment) and control (conventional treatment) groups. The intervention was performed for both groups for five sessions, twice a week. The two groups were compared after the intervention for primary outcome measures including maximum phonation time, jitter, shimmer, harmonic-to-noise ratio, and consensus auditory-perceptual evaluation of voice, and for secondary outcome measures including the voice handicap index, the voice activity and participation profile, the voice-related pain scale, and the vocal tract discomfort scale. RESULTS: Within-group primary outcome comparison showed that both groups showed significant improvement in maximum phonation time and consensus auditory-perceptual evaluation of voice indices after treatment. the between-group comparison showed that the maximum phonation time increased significantly in the intervention group after the treatment (P = 0.03) and the effect size was large (es = 1.05). within-group secondary outcome comparison showed that all indices improved significantly in both groups except for the voice-related pain scale frequency. The between-group comparison showed that except for voice-related pain scale frequency, the intervention group reported significantly more improvement in all other self-reporting indices with a large effect size. CONCLUSIONS: The study showed that adding cricothyroid visor maneuver to conventional voice-facilitating techniques, compared to conventional treatment alone, resulted in a significant increase in maximum phonation time, reduction in pain and vocal tract discomfort, increase in activity and participation, and improvement in voice-handicapped index in primary muscle tension dysphonia patients. Therefore adding cricothyroid visor maneuver to other treatments can be an effective method in improving primary muscle tension dysphonia which needs more studies in the future.

Comparative Investigation of Laryngeal Palpation Scale Between Primary and Secondary Muscle Tension Dysphonia.

OBJECTIVES: Muscle tension dysphonia (MTD) is a condition that is often assessed through palpation examination. The laryngeal palpation scale (LPS) is a reliable and valid tool developed to evaluate patients with MTD. MTD is classified into primary (without tissue reactions) and secondary (with tissue reactions). Primary MTD is caused by muscle hyperfunction, while maladaptive compensation typically leads to secondary MTD. The objective of this study was to compare the LPS scores between primary and secondary MTD. METHODS: This study is a cross-sectional analytical comparative study. It included 39 participants (10 men and 29 women) who were divided into two groups: primary MTD and secondary MTD with mass lesions (20 with primary MTD and 19 with secondary MTD). Each type of MTD was diagnosed by a qualified otolaryngologist. The participants were assessed using the LPS, which comprises 45 variables evaluated across three subscales. RESULTS: The results of the current study showed that there is a difference between the primary MTD and secondary MTD in the subscale of patients with symptomatic complaints of the item pain at rest/speaking (Pv = 0.001) and pain level (Pv = 0.019) and the subscale of palpation the item cricothyroid (left) in dynamic conditions (tenderness; Pv = 0.013). In other LPS items, no difference was observed between primary MTD and secondary MTD in all three subscales (Pv ≥ 0.05). CONCLUSIONS: The LPS scores for pain items during rest/speaking and the pain level, as well as the left cricothyroid (tenderness) item, were different between the primary MTD and secondary MTD groups. However, the other LPS items did not show any difference between the primary MTD and secondary MTD groups. Further investigation on palpation findings with LPS in larger samples in both groups and with objective measurements such as electromyography are recommended.

Efficacy of Voice Therapy in Rehabilitation of Muscle Tension Dysphonia in Patients of Nonlaryngeal Head and Neck Cancer: A Sequelae of Chemoradiotherapy.

The association of voice disorders in laryngeal cancers has been studied extensively; however Dysphonia associated with chemo-radiation in non laryngeal Head and Neck cancer (HNC) is a new area of practice in voice clinics. This study thus aimed to evaluate the efficacy of voice rehabilitation among non-laryngeal HNC survivors who were treated with curative RadioTherapy (RT)/Chemoradiotherapy (CRT) in adjunct with or without surgery. This tertiary institutional assessor blinded quasi experimental study after inclusion and exclusion criteria consisted of a study cohort of 128 patients who within 1-3 months of completion of treatment for HNC reported to the laryngology clinic for voice complaints and throat discomfort. All patients underwent documentation of laryngeal endoscopic imaging, acoustics assessment, Aronson's Laryngeal Palpatory Method (LPM) and Voice Handicap Index (VHI). Thereafter they were subjected to Vocal Rehabilitation Therapy (VRT) which constituted of Manual circumlaryngeal therapy, SOVTE, and vocal hygiene program. Re-evaluation of the vocal parameters was done at 6 weeks and 3 months from the start of the VRT. All parameters were significantly altered at 6 weeks and 3 months follow-up. Post VRT the videolaryngoscopic findings showed reduction in abnormal supraglottic MTPs with subsequent good approximation of true cords and reduction of involvement of supralaryngeal activities. The Dysphonia Severity Index (DSI) impairment levels and VHI scores showed significant improvement from the baseline to both at 6 weeks and 3 months of VRT (p < 0.001). DSI and VHI scores even showed significant improvement between 6 weeks to 3 months of therapy. There was highly significant correlation of VRT with/without surgery, with CRT and in non-smokers at 6 weeks and 3 months of VRT. In non-laryngeal head and neck malignancies, VRT offered as early as within 1-3 months of completion of treatment of HNC ameliorates surgical and chemo-radiation induced 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.

Relationships Between Laryngoscopic Analysis Metrics of Supraglottic Compression and Vocal Effort in Primary Muscle Tension Dysphonia.

PURPOSE: Supraglottic compression is thought to underlie vocal effort in patients with primary muscle tension dysphonia (pMTD). However, the relationship between supraglottic compression and vocal effort in this clinical population remains unclear. Gold standard laryngoscopic assessment metrics for supraglottic compression are also lacking. The goals of this study were to identify metrics proposed in the literature that could distinguish patients diagnosed with pMTD from typical voice users and determine their relationships to the vocal effort. METHODS: Flexible laryngeal endoscopy was performed on 50 participants (25 pMTD, 25 controls). The presence of supraglottic compression was characterized using a categorical (nominal) scale and severity was quantified on ordinal and continuous scales. The three laryngoscopic metrics were correlated with self-perceived ratings of vocal effort on a 100 mm visual analog scale. RESULTS: Inter-rater reliability was strongest for the continuous scale (P's < 0.0001) compared to categorical (P's < 0.001) and ordinal (P's < 0.001) scales. The presence of different supraglottic compression patterns varied in both groups, and there were no significant group differences on categorical (P's > 0.05) scales. Mediolateral (M-L) supraglottic compression was significantly greater in the pMTD group (P < 0.0001), and anteroposterior (A-P) compression was significantly greater in the control group (P = 0.001) using continuous scales. There were no significant relationships between any of the three laryngoscopic metric types and vocal effort ratings (P's > 0.05), except for a significantly positive relationship between anterior-posterior compression on the ordinal scale and vocal effort in the control group (P = 0.047). CONCLUSIONS: Continuous scales are reliable and valid for distinguishing individuals with pMTD from those without voice disorders, especially occupational voice users. M-L supraglottic compression may be a better indicator of pMTD than A-P compression. However, the poor correlation between supraglottic compression and vocal effort suggests that one may not influence the other. Future studies should focus on other mechanisms underlying vocal effort in patients with pMTD.

An Euler-Bernoulli-type beam model of the vocal folds for describing curved and incomplete glottal closure patterns.

Incomplete glottal closure is a laryngeal configuration wherein the glottis is not fully obstructed prior to phonation. It has been linked to inefficient voice production and voice disorders. Various incomplete glottal closure patterns can arise and the mechanisms driving them are not well understood. In this work, we introduce an Euler-Bernoulli composite beam vocal fold (VF) model that produces qualitatively similar incomplete glottal closure patterns as those observed in experimental and high-fidelity numerical studies, thus offering insights into the potential underlying physical mechanisms. Refined physiological insights are pursued by incorporating the beam model into a VF posturing model that embeds the five intrinsic laryngeal muscles. Analysis of the combined model shows that co-activating the lateral cricoarytenoid (LCA) and interarytenoid (IA) muscles without activating the thyroarytenoid (TA) muscle results in a bowed (convex) VF geometry with closure at the posterior margin only; this is primarily attributed to the reactive moments at the anterior VF margin. This bowed pattern can also arise during VF compression (due to extrinsic laryngeal muscle activation for example), wherein the internal moment induced passively by the TA muscle tissue is the predominant mechanism. On the other hand, activating the TA muscle without incorporating other adductory muscles results in anterior and mid-membranous glottal closure, a concave VF geometry, and a posterior glottal opening driven by internal moments induced by TA muscle activation. In the case of initial full glottal closure, the posterior cricoarytenoid (PCA) muscle activation cancels the adductory effects of the LCA and IA muscles, resulting in a concave VF geometry and posterior glottal opening. Furthermore, certain maneuvers involving co-activation of all adductory muscles result in an hourglass glottal shape due to a reactive moment at the anterior VF margin and moderate internal moment induced by TA muscle activation. These findings have implications regarding potential laryngeal maneuvers in patients with voice disorders involving imbalances or excessive tension in the laryngeal muscles such as muscle tension dysphonia.

Bi-Weekly Voice Therapy Versus Weekly Voice Therapy for Muscle Tension Dysphonia.

OBJECTIVES: To compare the outcomes of bi-weekly voice therapy (BWVT) with weekly voice therapy on perception, acoustics, and quality of life for individuals with muscle tension dysphonia (MTD). METHODS: Thirty participants with MTD were enrolled either BWVT (40 min/session, two sessions per week for 4 weeks) or weekly voice therapy (40 min/session, once a week for 8 weeks). Auditory perceptual ratings, acoustic parameters, and the Mandarin version of the voice-related quality of life questionnaire (MV-RQOL) scores were statistically analyzed before and after treatment. RESULTS: There were significant improvements in the voice qualities such as overall grade, roughness, asthenia, and strain in both groups after treatment. Acoustics analyses showed that fundamental frequency, speaking fundamental frequency, jitter, shimmer, and cepstral peak prominence significantly improved in both groups after treatment. For the MV-RQOL questionnaire scores, the result also demonstrated that both groups felt significant improvements in voice-related quality of life after treatment. However, there were no significant differences between the two groups of treatment effects. CONCLUSIONS: Patients with MTD can restore voice qualities and quality of life if they are able to complete a full course of voice therapy, regardless of the intensity of voice therapy. However, if they can receive the BWVT, they would be able to regain their voice faster. The results of this study can be provided as a reference for clinicians when treating patients with MTD.

Use of Motion Capture Technology to Study Extrinsic Laryngeal Muscle Tension and Hyperfunction.

OBJECTIVES: Patients with primary muscle tension dysphonia (pMTD) commonly report paralaryngeal pain and discomfort, and extrinsic laryngeal muscle (ELM) tension and hyperfunction are commonly implicated. However, quantitative physiological metrics to study ELM movement patterns for the characterization of pMTD diagnosis and monitoring of treatment progress are lacking. The objectives of this study were to validate motion capture (MoCap) technology to study ELM kinematics, determine whether MoCap could distinguish ELM tension and hyperfunction between individuals with and without pMTD, and investigate relationships between common clinical voice metrics and ELM kinematics. METHODS: Thirty subjects (15 with pMTD and 15 controls) were recruited for the study. Sixteen markers were placed on different anatomical landmarks on the chin and anterior neck. Movements across these regions were tracked during four voice and speech tasks using two three-dimensional cameras. Movement displacement and variability were determined based on 16 key-points and 53 edges. RESULTS: Intraclass correlation coefficients demonstrated high intra- and inter-rater reliability (p's < 0.001). Other than greater movement displacements around the thyrohyoid space during longer phrasing (reading passage, 30-s diadochokinetics) and more movement variability in patients with pMTD, kinematic patterns between groups were similar across the 53 edges for the four voice and speech tasks. There were also no significant correlations between ELM kinematics and standard voice metrics. CONCLUSION: Results demonstrate the feasibility and reliability of MoCap for the study of ELM kinematics. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:3472-3481, 2023.

Quantification of False Vocal Fold Hyperfunction During Quiet Breathing in Muscle Tension Dysphonia.

BACKGROUND/OBJECTIVES: False vocal fold (FVF) hyperfunction during phonation is thought to be a diagnostic sign of primary muscle tension dysphonia (pMTD). However, hyperfunctional patterns with phonation are also observed in typical speakers. This study tested the hypothesis that FVF posturing during quiet breathing, as measured by the curvature of FVF, could differentiate patients with pMTD from typical speakers. METHODS: Laryngoscopic images were collected prospectively in 30 subjects with pMTD and 33 typical speakers. Images were acquired at the end of expiration and maximal inspiration during quiet breathing, during sustained /i/, and during loud phonation before and after a 30-min vocal loading task. The FVF curvature (degree of concavity/convexity) was quantified using a novel curvature index (CI, >0 for hyperfunctional/convex, <0 for "relaxed"/concave) and compared between the two groups. RESULTS: At end-expiration, the pMTD group adopted a convex FVF contour, whereas the control group adopted a concave FVF contour (mean CI 0.123 [SEM 0.046] vs. -0.093 [SEM 0.030], p = 0.0002) before vocal loading. At maximal inspiration, the pMTD group had a neutral/straight FVF contour, whereas the control group had a concave FVF contour (mean CI 0.012 [SEM 0.038] vs. -0.155 [SEM 0.018], p = 0.0002). There were no statistically significant differences in FVF curvature between groups in either the sustained voiced or loud conditions. Vocal loading did not change any of these relationships. CONCLUSIONS: A hyperfunctional posture of the FVFs during quiet breathing especially at end-expiration may be more indicative of a hyperfunctional voice disorder than supraglottic constriction during voicing. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:3449-3454, 2023.