Variations in adductor spasmodic dysphonia:Acoustic evidence

Acoustic analysis was used to gain information about the normal, aswell as the abnormal acoustic events associated with adductor spasmodic dysphonia (ADSD). This analysis was completed to determine whether specific acoustic events could be used to differentiate the voice of individuals with ADSD from those with normal voice. A group comparison between 14 women diagnosed with ADSD and 14 women (age-matched) with no evidence of vocal pathology or vocal dysfunction was completed. Phonatory breaks, aperiodicity, and frequency shifts, acoustic parameters previously identified in ADSD, were found throughout sustained vowel productions. The duration of the phonatory breaks and aperiodic segments was calculated and the amount of frequency shift was determined. The location of each acoustic event was marked relative to the onset of the vowel production. The subjects with ADSD presented with normal phonation and various amounts of each of the three acoustic parameters. Aperiodic segments primarily characterized the phonation of ADSD, followed by frequency shifts and phonatory breaks. The location of each of these acoustic events was within the midportion of the vowel production. The advantages of segmenting the acoustic waveform into these measures and separating the spasmodic events from normal phonation when examining laryngeal motor control of spasmodic dysphonics is discussed     

Adductor spasmodic dysphonia and muscular tension dysphonia: Acoustic analysis of sustained phonation and reading

Acoustic phonatory events were identified in 10 women diagnosed with adductor spasmodic dysphonia (ADSD) and compared to 5 women and 5 men diagnosed with muscle tension dysphonia (MTD). The three acoustic parameters examined during sustained vowel production and reading included phonatory breaks, aperiodicity, and frequency shifts. Intra- and intermeasurer correlations showed high reliability for the measures. Findings indicated that those with ADSD produced a greater number of aberrant acoustic events than those with MTD. The results suggested that: (1) only those with ADSD show evidence of phonatory breaks during vocalization, albeit a sustained vowel or voicing during reading; (2) those with ADSD demonstrate greater variation in the type of aberrant acoustic events produced as a function of speech task. The latter point suggests that control of the larynx varies as a function of task demand, a finding not evident in the functionally based disorder of MTD. MTD is a disorder that often presents itself in a similar clinical manner to ADSD because of its perceptual commonalties and resembling laryngoscopic characteristics. The acoustic analysis presented in this study could be used as a method to assist in distinguishing between the two disorder types.     

Adductor spasmodic dysphonia: case reports withacoustic analysis following botulinum toxin injection and acupuncture

We analyzed frequency and duration parameters of voice and speech in two men with adductor spasmodic dysphonia (SD). One was treated with botulinum toxin injection; the other received acupuncture therapy. Im provement after acupuncture therapy in terms of standard deviation of fundamental frequency, acoustic perturbation measurements, durational measurements of voice and speech, and spectrographic analysis was comparable to the results achieved with botulinum toxin injection. Voice and speech parameters were stable I year after acupuncture therapy.     

Botulinum Toxin Therapy for Abductor Spasmodic Dysphonia

Botulinum toxin has been widely accepted as an effective therapy for controlling the symptoms of adductor spasmodic dysphonia (ADSD). Reported experience with botulinum treatment for abductor spasmodic dysphonia (ABSD) has been less impressive. Factors that may impair outcomes for ABSD include differences in the pathophysiology of ADSD and ABSD and limitation of maximal dose from airway restriction with posterior cricoarytenoid muscle (PCA) weakness. We report our experience with botulinum injection of the PCA with an asymmetric dose escalation protocol, based on clinical observations that in ABSD, abductor spasms are often stronger on one side, usually the left. The nondominant side was injected with 1.25 units. Dominant side dose began at 5 units, with step-wise increments of 5 units per week until one of three endpoints was reached: Elimination of breathy voice breaks, complete abductor paralysis of the dominant side, or airway compromise. Fourteen of 17 patients achieved good or fair voice, with dominant-side doses ranging from 10 to 25 units. Exercise intolerance limited PCA dose in two patients. One patient had persisting breathiness that improved with medialization thyroplasty. Asymmetric botulinum toxin injection into PCA muscles can suppress abductor spasm in patients with ABSD, but breathiness may persist, because of inadequate glottal closure.     

Differential diagnosis of spasmodic dysphonia: A kinematic perspective

Although originally considered an hysterical functional disorder, spasmodic dysphonia (SD) appears to be a heterogeneic symptom complex that is associated with several neurological diseases. Perceptual, acoustic, and electromyographic studies have not clearly differentiated the underlying pathologies that result in spasmodic phonatory dysfunction. Kinematic analysis of documented laryngeal examinations during phonation and respiration indicates that particular different movement disorders affect laryngeal function and are associated with spasmodic phonatory characteristics. The particular features of dystonia, tremors, myoclonus, and progressive supranuclear pathology should be recognized, since they may present with disease focal to the laryngeal muscles. Other movement disorders may also be associated with spasmodic phonatory abnormalities, but are less likely to be focal. Treatment of SD signs and symptoms is more likely to be successful and assessments of treatment more likely to be meaningful if the underlying pathophysiology of spasmodic phonatory behavior is identified.     

Longitudinal Effects of Botulinum Toxin Injections on Voice-Related Quality of Life (V-RQOL) for Patients with Adductory Spasmodic Dysphonia

Adductory spasmodic dysphonia is a focal dystonia of laryngeal muscles. Patients with this disorder typically have severe vocal difficulties, with significant functional, social, and emotional consequences. There is no widely accepted cure for this condition, however, botulinum toxin injections of the thyroarytenoid muscles are considered by most voice clinicians to be the state of the art treatment. Based on extensive experience treating patients for adductory spasmodic dysphonia, we feel that traditional means of voice assessment do not adequately measure either the disease severity or the treatment outcomes. That is, listening to or acoustically analyzing limited phonatory samples does not capture the functional, social, and emotional consequences of this disorder. These consequences will be reflected in a patient's voice-related quality of life (V-RQOL). Using a validated voice outcomes instrument, the V-RQOL Measure, the purpose of this study was to quantify longitudinal changes in the V-RQOL of patients with adductory spasmodic dysphonia who are undergoing botulinum toxin injections. Twenty-seven consecutive new patients presenting with dysphonia to our institution during an 18-month period were diagnosed with adductory spasmodic dysphonia, and treated patients were evaluated prospectively using the V-RQOL Measure. Results indicated that (1) V-RQOL was initially very low for these patients, (2) botulinum toxin injections improved it significantly for each injection cycle studied, and (3) the magnitude of the treatment effect appears to change across injections.     

Laryngeal Botulinum Toxin Injection: Can It Be a Cause of Obstructive Sleep Apnea as an Adverse Effect?

Spasmodic dysphonia is a chronic voice disorder that is characterized by involuntary spasms of the laryngeal muscles during speech production. Botulinum toxin injection into to the laryngeal muscles is the most common and effective treatment of choice for symptoms of spasmodic dysphonia. We present a 44-year-old man with adductor spasmodic dysphonia who was diagnosed as having upper airway obstruction in a polysomnographic examination during sleep after a botulinum toxin injection.     

Spastic/spasmodic vs. tremulous vocal quality: motor speech profile analysis

Strained, strangled, and tremulous vocal qualities that are typically seen in adductor spasmodic dysphonia (ADSD), voice tremor (Tremor), and the spastic dysarthria of amyotrophic lateral sclerosis (ALS) may sound similar and be difficult to differentiate. The purpose of this study was to determine if these vocal qualities of neurologic origin could be differentiated on the basis of acoustic and motor speech parameters. Three groups of subjects (ADSD, ALS, and Tremor) were analyzed by the Motor Speech Profile System (Kay Elemetrics, Lincoln Park, NJ) for fundamental frequency (Fo), standard deviation of Fo, diadochokinetic rate (ddk), standard deviation of ddk, mean intensity and standard deviation of ddk, frequency and amplitude variability in connected speech, and speaking rate in connected speech. Profiles of the three groups are presented with the significant features that differentiated one from the other.     

Objective Voice Analysis for Dysphonic Patients: A Multiparametric Protocol Including Acoustic and Aerodynamic Measurements

The purpose was to determine the clinical value of a multiparametric objective voice evaluation protocol including acoustic and aerodynamic parameters measured mainly on a sustained /a/. This was done by comparison with perceptual analysis of continuous speech by a jury composed of 6 experienced listeners. Voice samples (continuous speech) from 63 male patients with dysphonia and 21 control subjects with normal voices were recorded and assesed by a jury of listeners. The jury was instructed to classify voice samples according to the G (overall dysphonia) component of the GRBAS score on a 4-point scale ranging from 0 for normal to 3 for severe dysphonia. Objective parameters were recorded on an EVA^® workstation. As usual with this type of system, parameters were measured mainly on a sustained /a/. Measured parameters included fundamental frequency (F₀), intensity, jitter, shimmer, signal-to-noise ratio, Lyapunov coefficient (LC), oral airflow (OAF), maximum phonatory time (MPT), and vocal range (range). Estimated subglottic pressure (ESGP) was determined on a series of /pa/. Discriminant analysis was performed to detect correlation between jury classification and combinations of parameters. Results showed that a nonlinear combination of only six parameters (range, LC, ESGP, MPT, signal-to-noise ratio, and F₀) allowed 86% concordance with jury classification. Discussion deals with the relative importance of the different objective parameters for discriminant analysis. Special emphasis is placed on two measurements rarely made in routine clinical workup, i.e., estimated subglottic pressure and Lyapunov coefficient.     

Symptomatology of adductor spasmodic dysphonia: A physiologic model

Vocal symptomatology of adductor spasmodic dysphonia (SD) is reviewed critically from historical, epidemiologic, and clinical perspectives. A model of symptomatology of this disorder based on a large patient population, and clinical and physiologic observations is advanced. The model incorporates crucial symptomatic and asymptomatic phonatory and nonphonatory physiologic parameters of laryngeal behavior in these patients. These parameters include vocal fold contact area, vocal fold collision force, glottic compression, and subglottic air pressure. Inappropriate efferent discharges from brain-stem basal ganglia are hypothesized as causing overadduction of the vocal folds in phonation, generating the basic and fundamental vocal symptom of adductor SD—strained, strangled, overpressured voice quality. Cortical loops are implicated as accountable for compensatory vocal behavior, not as the primary site of the disorder. Symptom occurrence, variability, magnitude, effects, and failure of treatment approaches, as well as recurrence of symptoms after ablative or invasive procedures, are explained by this model. The model also predicts that symptomatology of adductor spasmodic dysphonia is unique to this disorder and that symptoms are phonotopically organized. The minimal diagnostic battery based on the model is presented, and it is shown how this battery aids in the differential diagnosis of adductor SD and other phonatory disorders that closely mimic the vocal symptoms of adductor spasmodic dysphonia, including tremor.     

A comparison of injection techniques using botulinum toxin injection for treatment of the spasmodic dysphonias

The benefit duration and side effects following effective treatment of spasmodic dysphonia or voice tremor using botulinum toxin injection were studied following 477 open trial unilateral or bilateral injections provided to 178 patients. A comparison of unilateral and bilateral injections in male and female patients with adductor spasmodic dysphonia demonstrated an increased benefit duration following unilateral injections in women, longer periods of breathiness in men than in women following bilateral or unilateral injections, and a trend for reduced benefit durations following repeated treatments using bilateral injections. Outcomes were similar in the adductor spasmodic dysphonia and vocal tremor groups following thyroarytenoid injection while benefit durations were reduced and side effects lasted longer in patients with abductor spasmodic dysphonia following cricothyroid injections. Long-term benefit > 1 year occurred in 12.3% of patients following injection.     

Classification of Dysphonic Voice: Acoustic and Auditory-Perceptual Measures

The purpose of this study was (1) to determine the relationship between acoustic measures and auditory-perceptual dimensions of overall voice severity and pleasantness and (2) to evaluate the ability of acoustic and auditory-perceptual measures to discriminate normal from dysphonic voices. Thirty adult dysphonic speakers and six, age-matched normal control speakers were asked to provide oral reading samples of the Rainbow Passage. Acoustic analysis of the speech samples was used to identify abnormal phonatory events associated with dysphonia. The acoustic program calculated long-term average spectral measures, glottal noise measures, and those measures based on linear prediction (LP) modeling. Twelve adult listeners judged overall voice severity and pleasantness from the connected speech samples using direct magnitude estimation (DME) procedures. The acoustic measures accounted for 48% of overall voice severity and 40% of voice pleasantness for dysphonic speakers. The classification performance of the acoustic measures and auditory-perceptual measures was quantified using logistic regression analysis. When acoustic measures or auditory-perceptual measures were considered in isolation, classification was generally accurate and similar across measures. Classification accuracy improved to 100% when acoustic and auditory-perceptual measures were combined. These data provide further support for use of both auditory-perceptual evaluation and acoustic analyses for classifying and evaluating dysphonia.     

Psychogenic spasmodic dysphonia: A case study with expert opinions

Spasmodic (spastic) dysphonia (SD) is considered by some to be a neurologic syndrome and by others a symptom complex of multiple etiologies, neurologic and psychogenic. A case of a 26-year-old female psychiatric nurse with psychogenic SD (PSD) is presented. The dysphonia was alleviated within one session of voice therapy. Psychogenic etiology was established by the author, based on three diagnostic criteria—symptom incongruity, symptom reversibility, and symptom psychogenicity. Seven nationally recognized voice experts listened to audio-recorded samples of the patient's pre- and posttherapy voice during conversational speech. The experts agreed that the dysphonia was psychogenic and characterized it as staccato-like speech, effortful phonation, and interrupted flow of speech; six characterized it with intermittent voice arrests (voice stoppages); five with hoarse-harsh voice; and four with waxing and waning, strained-strangled phonation. These are often described as salient features of SD. Nevertheless, the experts disagreed among themselves as to whether the dysphonia was characteristic of SD and should be labeled as such. The author argues that as long as the voice characteristics and pathophysiologic findings that constitute SD are not well delineated, and as long as the diagnosis of SD is based on symptoms alone, patients with psychogenic or poorly understood voice disorders are likely to be misdiagnosed with organic (neurologic) SD and thus subjected to undue medical treatment. The author also argues that the debate over the etiology of SD can be resolved if SD is considered a neurologic syndrome, PSD a nonorganic phonatory disorder that mimics the syndrome, and if the voice symptoms and pathophysiologic characteristics of SD are well defined and agreed on.     

Analysis of factors affecting botulinum toxin results in spasmodic dysphonia

This study was designed to investigate how variations in patterns of injection could improve the efficacy of botulinum toxin injections in relieving the symptoms of adductor spasmodic dysphonia. A total of 64 adductor spasmodic dysphonia patients who were injected using indirect laryngoscopic localization (for a total of 426 injections) were analyzed retrospectively using their own subjective data on duration of voice improvement, optimal voice improvement, breathiness side effects, and intervals between treatments. Injection to both the thyroarytenoid (TA) and the lateral cricoarytenoid (LCA) simultaneously gave the best voice results; the overall improvement from baseline was the longest lasting, and the period during which the voice was the best was the longest lasting. TA + LCA also gave the shortest duration of undesirable breathiness side effect. On the basis of these data, it seems reasonable to recommend that initial botulinum toxin therapy for adductor spasmodic dysphonia patients should be a single unilateral injection placed strategically at the posterior portion of the TA and directed toward the LCA so that both muscle groups are affected.     

Acoustic analysis of voice in individuals with amyotrophic lateral sclerosis and perceptually normal vocal quality

Currently, early phonatory changes in amyotrophic lateral sclerosis(ALS) are not well understood. The aim of this study was to compare acoustic parameters of voice in ALS subjects who demonstrated perceptually normal vocal quality on sustained phonation with a control group. We hypothesized that objective analysis of voice would reveal significant differences on specific acoustic parameters of voice compared to the control group. Results revealed statistically significant differences between the two groups on measures related to frequency range and phonatory stability. The findings suggest that early bulbar signs affecting the laryngeal system may be present in patients with ALS before the occurrence of perceptually aberrant vocal characteristics.     

Acoustic Measures of Phonatory Improvement Secondary to Treatment by Oral Corticosteroids in a Professional Singer: A Case Report

Short-term administration of corticosteriods is sometimes indicated for professional voice users experiencing laryngeal edema and/or inflammation. Unfortunately, no data are available to document the effectiveness of these medications to improve phonatory parameters. We present a case report of a 32-year-old male professional singer with vocal fold edema experiencing imminent vocal demands who was prescribed a 6-day course (dose-pack) of oral methyl prednisolone. Endoscopic and stroboscopic evaluations were completed premedication and postmedication, and acoustic measures of phonatory function were obtained premedication, 3 days during the dose cycle, 5 days during the dose cycle, and 1 day postmedication. Postmedication results revealed an increase in fundamental frequency (F0) and large decreases in jitter, shimmer, long-term frequency, and amplitude variability. These corresponded with patient and evaluator perceptual measures of improved voice, and with endoscopic observations of reduced edema. The benefits and risks of corticosteroid therapy are discussed, specific to their use in the professional voice population.     

Spasmodic dysphonia symptoms as initial presentation of amyotrophic lateral sclerosis

A patient initially diagnosed with adductor-type spasmodic dysphonia was referred for botulinum toxin (Botox) injections, but found on subsequent evaluation to have amyotrophic lateral sclerosis, and therefore Botox was not administered. This unique case underscores the need to delay botulinum toxin treatments in any patient with recent onset symptoms, and to obtain thorough motor speech and voice, otolaryngologic, and neurologic evaluation in all patients prior to consideration for injection.     

Objective Indices of Perceived Vocal Strain

BackgroundA limited number of experiments have investigated the perception of strain compared to the voice qualities of breathiness and roughness despite its widespread occurrence in patients who have hyperfunctional voice disorders, adductor spasmodic dysphonia, and vocal fold paralysis among others.ObjectiveThe purpose of this study is to determine the perceptual basis of strain through identification and exploration of acoustic and psychoacoustic measures.MethodsTwelve listeners evaluated the degree of strain for 28 dysphonic phonation samples on a five-point rating scale task. Computational estimates based on cepstrum, sharpness, and spectral moments (linear and transformed with auditory processing front-end) were correlated to the perceptual ratings.ResultsPerceived strain was strongly correlated with cepstral peak prominence, sharpness, and a subset of the spectral metrics. Spectral energy distribution measures from the output of an auditory processing front-end (ie, excitation pattern and specific loudness pattern) accounted for 77–79% of the model variance for strained voices in combination with the cepstral measure.ConclusionsModeling the perception of strain using an auditory front-end prior to acoustic analysis provides better characterization of the perceptual ratings of strain, similar to our prior work on breathiness and roughness. Results also provide evidence that the sharpness model of Fastl and Zwicker (2007) is one of the strong predictors of strain perception.     

A report on alterations to the speaking and singing voices of four women following hormonal therapy with virilizing agents

Four women aged between 27 and 58 years sought otolaryngological examination due to significant alterations to their voices, the primary concerns being hoarseness in vocal quality, lowering of habitual pitch, difficulty projecting their speaking voices, and loss of control over their singing voices. Otolaryngological examination with a mirror or flexible laryngoscope revealed no apparent abnormality of vocal fold structure or function, and the women were referred for speech pathology with diagnoses of functional dysphonia. Objective acoustic measures using the Kay Visipitch indicated significant lowering of the mean fundamental frequency for each woman, and perceptual analysis of the patients' voices during quiet speaking, projected voice use, and comprehensive singing activities revealed a constellation of features typically noted in the pubescent male. The original diagnoses of a functional dysphonia were queried, prompting further exploration of each woman's medical history, revealing in each case onset of vocal symptoms shortly after commencing treatment for conditions with medications containing virilizing agents (eg, Danocrine (danazol), Deca-Durabolin (nandrolene decanoate), and testosterone). Although some of the vocal symptoms decreased in severity with the influences from 6 months voice therapy and after withdrawal from the drugs, a number of symptoms remained permanent, suggesting each subject had suffered significant alterations in vocal physiology, including muscle tissue changes, muscle coordination dysfunction, and propioceptive dysfunction. This retrospective study is presented in order to illustrate that it was both the projected speaking voice and the singing voice that proved so highly sensitive to the virilization effects. The implications for future prospective research studies and responsible clinical practice are discussed.     

The Effects of a Specific Speech and Language Training Program on Students of a Radio Announcing Course

The purpose of this study was to determine whether individuals show differences in speech and voice during reading of the same news before and after attending a radio announcing course. Twenty-five students of a Radio Announcing Course in Sao Paulo city, 17 men and 8 women, aged 19 to 55 years, participated in this study. The readings were recorded in a professional audio studio, and the speech samples were submitted to perceptual and acoustic analysis. For the perceptual analysis, the samples were randomly presented in pairs and five trained speech pathologists identified each recording as pre- and posttraining, and also justified their choices by indicating what parameters better based their judgment: type of voice, articulation and pronunciation, loudness, pitch, resonance, speech rate, respiratory coordination, and use of emphasis. The acoustic parameters analyzed were mean, minimum, and maximum fundamental frequency, frequency range, text duration, and pause duration. The perceptual analysis showed that the posttraining speech samples were considered the best productions in 80% of the evaluations. Emphasis characterized the readings (70.4%), followed by type of voice (44.8%) and pitch (40.8%). Acoustic analysis showed higher mean fundamental frequency and increase of frequency range posttraining. These results indicated richer modulation in the posttraining readings. There are differences in the readings of the same news pre- and posttraining in a radio announcing course, and the posttraining reading was considered the best production, indicating the positive effect of the training.