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.

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.

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.

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 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.

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.

Extrinsic Laryngeal Muscle Tension in Primary Muscle Tension Dysphonia with Shear Wave Elastography

OBJECTIVES

It has been assumed that patients with primary muscle tension dysphonia (pMTD) have more extrinsic laryngeal muscle (ELM) tension, but tools to study this phenomenon lack. Shear wave elastography (SWE) is a potential method to address these shortcomings. The objectives of this study were to apply SWE to the ELMs, compare SWE measures to standard clinical metrics, and determine group differences in pMTD and typical voice users before and after vocal load.

METHODS

SWE measurements of the ELMs from ultrasound examinations of the anterior neck, supraglottic compression severities from laryngoscopic images, cepstral peak prominences (CPP) from voice recordings, and self-perceptual ratings of vocal effort and discomfort were obtained in voice users with (N = 30) and without (N = 35) pMTD, before and after a vocal load challenge.

RESULTS

ELM tension significantly increased from rest-to-voiced conditions in both groups. However, the groups were similar in their ELM stiffness levels at SWE at baseline, during vocalization, and post-vocal load. Levels of vocal effort and discomfort and supraglottic compression were significantly higher and CPP was significantly lower in the pMTD group. Vocal load had a significant effect on vocal effort and discomfort but not on laryngeal or acoustic patterns.

CONCLUSION

SWE can be used to quantify ELM tension with voicing. Although the pMTD group reported significantly higher levels of vocal effort and vocal tract discomfort and, on average, exhibited significantly more severe supraglottic compression and lower CPP values, there were no group differences in levels of ELM tension using SWE.

LEVEL OF EVIDENCE

2 Laryngoscope, 133:3482-3491, 2023.

Automated Creak Differentiates Adductor Laryngeal Dystonia and Muscle Tension Dysphonia

OBJECTIVE

The purpose of this study was to determine whether automated estimates of vocal creak would differentiate speakers with adductor laryngeal dystonia (AdLD) from speakers with muscle tension dysphonia (MTD) and speakers without voice disorders.

METHODS

Sixteen speakers with AdLD, sixteen speakers with MTD, and sixteen speakers without voice disorders were recorded in a quiet environment reading aloud a standard paragraph. An open-source creak detector was used to calculate the percentage of creak (% creak) in each of the speaker's six recorded sentences.

RESULTS

A Kruskal-Wallis one-way analysis of variance revealed a statistically significant effect of group on the % creak with a large effect size. Pairwise Wilcoxon tests revealed a statistically significant difference in % creak between speakers with AdLD and controls as well as between speakers with AdLD and MTD. Receiver operating characteristic curve analyses indicated that % creak differentiated AdLD from both controls and speakers with MTD with high sensitivity and specificity (area under the curve statistics of 0.94 and 0.86, respectively).

CONCLUSION

Percentage of creak as calculated by an automated creak detector may be useful as a quantitative indicator of AdLD, demonstrating the potential for use as a screening tool or to aid in a differential diagnosis.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:2687-2694, 2023.

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. 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 in to 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.

Combined treatment of muscle tension dysphonia: voice therapy with instrumental postural rehabilitation

Objectives

This investigation aimed to propose a new rehabilitation technique that combines voice exercises and instrumental postural rehabilitation for patients with muscle tension dysphonia (MTD).

Methods

We enrolled nine dysphonic patients (8 women and 1 man, aged 22-55 years). Voice assessment included strobovideolaryngoscopy, Maximum Phonation Time (MPT), perceptual evaluation by GRBAS scale and patient's self-rating by Italian version of the Voice Handicap Index (VHI). Vestibular function was evaluated by the Bed Side Examination and Video Head Impulse test (VHIT). Postural control was evaluated by Dynamic Posturography (DP) using the Sensory Organization Test (SOT) and analysing the Equilibrium Score (ES) and balance subsystems (somatosensorial, visual, vestibular).

Results

All cases underwent different types of voice exercises combined with balance training based on NeuroCom Balance Master Protocols, once a week for six 35-minutes sessions. After therapy, an improvement in MPT, VHI, GRBAS scores and endoscopic laryngeal features was obtained. DP results at baseline were normal and after therapy we showed a slight improvement of ES (somatosensorial and visual components).

Conclusions

A combined rehabilitation technique for MTD, by improving the attention to postural control, allows for significant improvement in vocal symptoms.

Postacute COVID-19 Laryngeal Injury and Dysfunction

Objective

Patients with COVID-19 are at risk for laryngeal injury and dysfunction secondary to respiratory failure, prolonged intubation, and other unique facets of this illness. Our goal is to report clinical features and treatment for patients presenting with voice, airway, and/or swallowing concerns postacute COVID-19.

Study Design

Case series.

Setting

Academic tertiary care center.

Methods

Patients presenting with laryngeal issues following recovery from COVID-19 were included after evaluation by our laryngology team. Data were collected via retrospective chart review from March 1, 2020, to April 1, 2021. This included details of the patient’s COVID-19 course, initial presentation to laryngology, and subsequent treatment.

Results

Twenty-four patients met inclusion criteria. Twenty (83%) patients were hospitalized, and 18 required endotracheal intubation for a median (range) duration of 14 days (6-31). Ten patients underwent tracheostomy. Patients were evaluated at a median 107 days (32-215) after their positive SARS-CoV-2 test result. The most common presenting concerns were dysphonia (n = 19, 79%), dyspnea (n = 17, 71%), and dysphagia (n = 6, 25%). Vocal fold motion impairment (50%), early glottic injury (39%), subglottic/tracheal stenosis (22%), and posterior glottic stenosis (17%) were identified in patients who required endotracheal intubation. Patients who did not need intubation were most frequently treated for muscle tension dysphonia (67%).

Conclusion

Patients may develop significant voice, airway, and/or swallowing issues postacute COVID-19. These complications are not limited to patients requiring intubation or tracheostomy. Multidisciplinary laryngology clinics will continue to play an integral role in diagnosing and treating patients with COVID-19–related laryngeal sequelae.

Clinical and Electromyographic Assessment of Swallowing in Individuals with Functional Dysphonia Associated with Dysphagia Due to Muscle Tension or Atypical Swallowing

Introduction: Over the past few years, attention has been paid to the coexistence of dysphonia with dysphagia, in the context of functional disorders. The aim of this work was to objectify logopaedic examination of dysphonic patients with coexisting swallowing difficulties by surface electromyography. Methods: The material of the work included 58 patients with muscle tension dysphonia (MTD). Each patient underwent otolaryngologic, phoniatric and logopaedic examination. We collected information about medical history and asked patients to fill out Reflux Symptom Index (RSI), Eating Assessment Tool (EAT-10), Dysphagia Handicap Index (DHI) and Swallowing Disorder Scale (SDS). The algorithm of dysphagia diagnostics in our clinic assumes parallel surface electromyography (SEMG) during Functional Endoscopic Evaluation of Swallowing. Results: In comparison to patients suffering from atypical swallowing, patients with muscle tension dysphagia (MTDg) obtained higher values from almost all questionnaires. Logopaedic evaluation revealed abnormalities in the structure and efficiency of the articulatory organs and in the assessment of primary functions. Patients with more abnormalities in logopaedic examination had significantly higher infrahyoid muscle activity during swallowing observed in EMG. Patients with non-normative swallowing pattern had significantly greater asymmetry of the average and maximum amplitude of masseters, as well as submental muscles. Patients with higher percent of muscles asymmetry gained higher scores in questionnaires. Conclusions: Surface electromyography objectifies logopaedic examination of patients with swallowing difficulties. The results of this work showed that, apart from longer swallows, patients with MTDg differ from patients with non-normative swallowing patterns in the muscle activity measured by SEMG, abnormalities in logopaedic evaluation and the severity of complaints reported by patients.

Characterization of Functional Dysphonia: Pre- and Post-Treatment Findings

OBJECTIVES

Functional dysphonia (FD) is one of the possible presentations of chronic dysphonia. Defined as dysphonia without gross abnormality of the larynx, FD manifests as aberrant muscle contractions resulting in mild-to-severe dysphonia. Despite increasing clinical awareness, diagnosis, and treatment strategies for FD remain challenging.

STUDY DESIGN

Institutional review board.

METHODS

A retrospective review of videostroboscopic examinations and EMR data from 109 patients treated for FD was performed. Videostroboscopy was analyzed by two independent reviewers and classified by laryngeal posturing and observer-rated quality of voice. Medical records were reviewed and patient characteristics, history of disease, and survey responses were collected. Statistics were calculated using JMP and SAS packages.

RESULTS

A total of 85.1% of subjects were female and the average voice handicap index (VHI30) score was 71.0/120. Average time to diagnosis of FD was 688 days and average time from diagnosis to treatment was 3.7 days. 44.0% of patients exhibited hyperadducted laryngeal posturing, 31.9% hypoadducted, and 24.2% showed a mixed posture. 98% of patient voices improved after treatment. 85% returned to normal voice and 10% maintained a mild residual dysphonia.

CONCLUSION

We describe here a large cohort of patients affected by FD, including clinical presentation and videostroboscopic findings. Our data show that most individuals with FD improve after specialized voice therapy once correctly diagnosed but that correct diagnosis and proper treatment was often significantly delayed.

LEVEL OF EVIDENCE

4-Case-series Laryngoscope, 131:E1957-E1964, 2021.

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.

Correlation of Glottic Gap and Voice Impairment in Presbyphonia

OBJECTIVE/HYPOTHESIS

The objective of this study was to investigate the glottic gap area as a significant marker for the severity of presbyphonia as it relates to patient-reported outcome measures (Voice Handicap Index-10 [VHI-10]) and stroboscopic findings.

STUDY DESIGN

Retrospective case-control study conducted in an academic tertiary voice center.

METHODS

Patients seen at a tertiary voice clinic who were diagnosed with presbyphonia without other organic laryngeal pathology from January 2014 to December 2017 were included. Clinical data and laryngeal videostroboscopy videos were collected. Still images at the point of vocal process approximation during adduction were captured, and the glottic gap area was measured using ImageJ. These were compared to a control cohort. Correlations were made using Wilcoxon rank sum test, Mann-Whitney U test, and Pearson correlation coefficients.

RESULTS

Thirty-three patients were included. Inter-rater reliability of glottic area measurement was strong (intraclass correlation coefficient = 0.73, P < .001). Compared to controls, presbyphonia patients had a larger glottic gap area (P < .001) and greater open-phase quotient on laryngeal videostroboscopy (P < .001). Larger glottic gap area did not correlate with patient-reported vocal function as measured by VHI-10 (P = .79) and did not correlate with presence of secondary muscle tension dysphonia (P = .99). In the presbyphonia cohort, the glottic gap area did not correlate with age (P = .29).

CONCLUSIONS

Glottic gap area at the point of vocal process approximation during phonation can be reliably measured. Patients with presbyphonia have a larger glottic gap area and greater open-phase quotient on stroboscopy, but these do not correlate with patient-reported voice impairment or the presence of secondary muscle tension dysphonia (MTD). These data suggest that dysphonia severity in presbyphonia is not fully explained by a glottic gap or secondary MTD alone.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1594-1598, 2021.

Injection laryngoplasty as adjunct treatment method for muscle tension dysphonia: Preliminary findings

Objectives

This study examined the effectiveness of injection laryngoplasty (IL) in muscle tension dysphonia (MTD) patients who did not fully respond to voice therapy. It was hypothesized that IL would improve voice quality and voice‐related quality of life measures in MTD.

Methods

A retrospective review was conducted on 37 patients with a primary diagnosis of MTD who underwent IL following a suboptimal response to voice therapy (mean age = 43.0 years; standard deviation [SD] = 13.4; range = 23 to 71). Outcome measures included laryngoscopic signs of supraglottic constriction, Voice Handicap Index‐10 (VHI‐10) scores, maximal phonation time, vowel fundamental frequency (F0), standard deviation of F0 (F0SD), harmonics‐to‐noise ratio (HNR), and smoothed cepstral peak prominence. These were compared between baseline and within 3 months following the IL procedure.

Results

There was significant decrease in supraglottic constriction. Mean (SD) of VHI‐10 scores decreased from 25.4 (5.7) at baseline to 15.3 (9.3) following IL. This improvement in VHI‐10 was observed in patients with and without baseline glottal insufficiency (GI). Mean (SD) of HNR (decibels) increased from 21.1 (5.4) at baseline to 22.8 (4.3) after IL. Only patients with GI demonstrated a significant improvement in HNR from baseline to post‐IL. No statistically significant differences in other acoustic measures were observed.

Conclusions

IL resulted in positive changes in voice‐related quality of life in MTD patients with and without GI. Acoustically, only those with GI demonstrated an increase in HNR following IL. Further studies are needed to examine the effects of IL in MTD.

Level of Evidence

4 Laryngoscope, 130:980–985, 2020

Comorbid Dysphagia and Dyspnea in Muscle Tension Dysphonia: A Global Laryngeal Musculoskeletal Problem

Objective

To characterize the associated symptoms of dysphagia and dyspnea among patients presenting with muscle tension dysphonia (MTD).

Study Design

Retrospective chart review performed over a 14-month period from October 2014 to December 2015.

Setting

Voice and swallowing center of a tertiary academic medical center.

Subjects and Methods

Thirty-eight patients with MTD were included for analysis. Clinical data were collected and analyzed, including perceptual voice evaluation and patient-reported outcomes measures.

Results

Among patients with a diagnosis of MTD, the incidence of reported dysphagia during clinical history and examination was 44.7%. Among patients with MTD, 60.5% had an EAT-10 (10-item Eating Assessment Tool) score ≥3 (ie, abnormal). Patients who reported dysphagia and/or had abnormal EAT-10 score (≥3) had significantly greater voice impairment than that of patients without dysphagia (P = .02). Patients who reported dysphagia also had significantly higher Clinical COPD Questionnaire scores than those of patients who reported only dysphonia (P = .002).

Conclusions

Patients presenting for dysphonia who are diagnosed with MTD have a high rate of comorbid dysphagia. Patients who reported dysphagia had significantly higher self-reported voice impairment and greater severity of breathing dysfunction as measured by the Clinical COPD Questionnaire. The coincidence of these symptoms in this patient cohort may suggest an underlying pathophysiology that has yet to be elucidated. Further prospective studies are needed to clarify the underlying cause of dysphagia and breathing dysfunction in the setting of MTD and to investigate diagnostic and therapeutic paradigms.

Chemodenervation of the Larynx

Botulinum neurotoxin (BoNT) has existed for thousands of years; however, it was not medically utilized until investigations into its therapeutic use began in sincerity during the late 1970s and 1980s. This, coupled with the reclassification of spasmodic dysphonia as a focal dystonia, led to the use of chemodenervation for this disorder, which has since become a refined technique. Indeed, due to its safety and efficacy, BoNT has been investigated in multiple neurolaryngology disorders, including spasmodic dysphonia, vocal tremor, and muscle tension dysphonia. BoNT has been shown to be a useful and safe adjunct in the treatment for these disorders and may reduce or eliminate oral pharmacotherapy and/or prevent the need for a surgical intervention. We present the historical background, development, proposed mechanisms of action, uses, and techniques for administering BoNT for laryngeal disorders, with a particular focus on spasmodic dysphonia.

Cortical Silent Period Reveals Differences Between Adductor Spasmodic Dysphonia and Muscle Tension Dysphonia

BACKGROUND

The pathophysiology of adductor spasmodic dysphonia (AdSD), like other focal dystonias, is largely unknown.

OBJECTIVE

The purposes of this study were to determine (a) cortical excitability differences between AdSD, muscle tension dysphonia (MTD), and healthy controls; (b) distribution of potential differences in cranial or skeletal muscle; and (c) if cortical excitability measures assist in the differential diagnosis of AdSD and MTD.

METHODS

Ten participants with adductor spasmodic dysphonia, 8 with muscle tension dysphonia, and 10 healthy controls received single and paired pulse transcranial magnetic stimulation (TMS) to the primary motor cortex contralateral to tested muscles, first dorsal interosseus (FDI), and masseter. We tested the hypothesis that cortical excitability measures in AdSD would be significantly different from those in MTD and healthy controls. In addition, we hypothesized that there would be a correlation between cortical excitability measures and clinical voice severity in AdSD.

RESULTS

Cortical silent period duration in masseter and FDI was significantly shorter in AdSD than MTD and healthy controls. Other measures failed to demonstrate differences.

CONCLUSION

There are differences in cortical excitability between AdSD, MTD, and healthy controls. These differences in the cortical measure of both the FDI and masseter muscles in AdSD suggest widespread dysfunction of the GABAB mechanism may be a pathophysiologic feature of AdSD, similar to other forms of focal dystonia. Further exploration of the use of TMS to assist in the differential diagnosis of AdSD and MTD is warranted.

Aerodynamic profiles of women with muscle tension dysphonia/aphonia

PURPOSE

In this study, the authors aimed to (a) determine whether phonatory airflows and estimated subglottal pressures (est-Psub) for women with primary muscle tension dysphonia/aphonia (MTD/A) differ from those for healthy speakers; (b) identify different aerodynamic profile patterns within the MTD/A subject group; and (c) determine whether results suggest new understanding of pathogenesis in MTD/A.

METHOD

Retrospective review of aerodynamic data collected from 90 women at the time of primary MTD/A diagnosis.

RESULTS

Aerodynamic profiles were significantly different for women with MTD/A as compared with healthy speakers. Five distinct profiles were identified: (a) normal flow, normal est-Psub; (b) high flow, high est-Psub; (c) low flow, normal est-Psub; (d) normal flow, high est-Psub; and (e) high flow, normal est-Psub.

CONCLUSIONS

This study is the first to identify distinct subgroups of aerodynamic profiles in women with MTD/A and to quantitatively identify a clinical phenomenon sometimes described in association with it-"breath holding"-that is shown by low airflow with normal est-Psub. Results were consistent with clinical claims that diverse respiratory and laryngeal functions may underlie phonatory patterns associated with MTD/A. One potential mechanism, based in psychobiological theory, is introduced to explain some of the variability in aerodynamic profiles of women with MTD/A.

Effects of voice therapy on relative fundamental frequency during voicing offset and onset in patients with vocal hyperfunction

PURPOSE

The purpose of this study was to determine whether the relative fundamental frequency (RFF) surrounding a voiceless consonant in patients with hyperfunctionally related voice disorders would normalize after a successful course of voice therapy.

METHOD

Pre- and posttherapy measurements of RFF were compared in 16 subjects undergoing voice therapy for voice disorders associated with vocal hyperfunction.

RESULTS

A 2-way analysis of variance showed a statistically significant effect of both cycle of vibration near the consonant and therapy phase (pre- vs. post-), with p < .001. A post hoc paired Student's t test showed that posttherapy RFF measurements were significantly higher (more typical; p < .0001) than pretherapy measurements.

CONCLUSIONS

Prior to therapy, participants exhibited lowered RFF values, similar to those found previously (Stepp, Hillman, & Heaton, 2010). After successful completion of voice therapy, RFF values increased toward patterns seen previously in individuals with healthy typical voice. The goal of voice therapy in these patients was to reduce laryngeal muscle tension; therefore, the increase of RFF toward more typical values may be indicative of decreased baseline laryngeal muscle tension resulting from therapy. Results are discussed further in terms of necessary research to incorporate RFF as a clinical measure of vocal hyperfunction.