Acoustic Measures of Symptoms in Abductor Spasmodic Dysphonia

Speech of patients with abductor spasmodic dysphonia (ABSD) was analyzed using acoustic analyses to determine: (1) which acoustic measures differed from controls and were independent factors representing patients' voice control difficulties, and (2) whether acoustic measures related to blinded perceptual counts of the symptom frequency in the same patients. Patients' voice onset time for voiceless consonants in speech were significantly longer than the controls (p = 0.015). A principle components analysis identified three factors that accounted for 95% of the variance: the first factor included sentence and word duration, frequency shifts, and aperiodic instances; the second was phonatory breaks; and the third was voice onset time. Significant relationships with perceptual counts of symptoms were found for the measures of acoustic disruptions in sentences and sentence duration. Finally, a multiple regression demonstrated that the acoustic measures related well with the perceptual counts (r² = 0.84) with word duration most highly related and none of the other measures contributing once the effect of word duration was partialed out. The results indicate that some of the voice motor control deficits, namely aperiodicity, phonatory breaks, and frequency shifts, which occur in patients with ABSD, are similar to those previously found in adductor spasmodic dysphonia. Results also indicate that acoustic measures of intermittent disruptions in speech, voice onset time, and speech duration are closely related to the perception of symptom frequency in the disorder.     

Clinical Characteristics and Voice Analysis of Patients With Mutational Dysphonia: Clinical Significance of Diplophonia and Closed Quotients

The aim of this study was to investigate the acoustic and electroglottographic characteristics of patients with mutational dysphonia before and after voice therapy. The clinical records of 15 patients with mutational dysphonia were reviewed, and their voice recordings were analyzed with the help of the Lx Speech Studio program (Laryngograph Ltd, London, UK). After voice therapy combined with the manual compression method, the subjects' voices lowered in pitch and improved in quality. In addition, we classified the mutational dysphonia into four categories according to the presence of diplophonia and closed quotients. The most common type among the categories was characterized by a bimodal distribution of fundamental frequency (diplophonia), accompanied by a low closed quotient (falsetto voice) at high frequencies. However, the results also showed that mutational dysphonia cannot be generalized as always having a falsetto voice, as shown in other types. The effect of therapy was different for each type, and those cases with both diplophonia and a non-trained falsetto voice could be treated more readily. Consequently, the diplophonia and closed quotient, which were easily analyzed using Lx Speech Studio program, are important factors in the classification of mutational dysphonia. Identification of these characteristics may affect treatment choices, facilitate monitoring of the efficacy of therapy, and aid in estimating prognosis.     

Extrinsic Laryngeal Muscular Tension in Patients with Voice Disorders

The objective of this study was to establish a standard clinical evaluation tool for assessment by palpation of extrinsic laryngeal muscular tension (ELMT) and investigate the relationship between ELMT and different voice disorder diagnosis categories, particularly muscle misuse dysphonia (MMD), and the presence or absence of gastroesophageal reflux (GER). A palpation technique and tension grading system for four separate muscle groups (suprahyoid, thyrohyoid, cricothyroid, and pharyngolaryngeal) were established. 465 patients, 65% female and 35% male, were assessed sequentially and ELMT results were analyzed in relation to diagnosis and reflux status. A strong relationship was found between thyrohyoid muscle tension and both GER and MMD (p < or = 0.01). Thyrohyoid muscle tension is the only group that demonstrated a significant relationship with MMD. No significant difference in the ELMT scores was found between GER and non-GER patients, although a possible causal relationship was found between MMD type 3 and reflux. It is postulated that palpation of extrinsic laryngeal muscles can yield important information about internal laryngeal postures and diagnosis of muscle misuse voice disorders, particularly MMD type 3 (anteroposterior supraglottic compression). Integration of this technique into routine laryngeal examination can be a significant aid to diagnostic accuracy.     

Use of topical lidocaine in the treatment of muscle tension dysphonia

This investigation explored the potential usefulness of topical lidocaine in the treatment of muscle tension dysphonia. Three patients with this disorder, who were previously unresponsive to standard voice therapy, were treated with lidocaine. In each case, the outcome was prompt, clinically significant, and sustained. Persistently high-pitched and shrill vocal quality was converted to near normal voice patterns within 15 minutes after transcricothyroid membrane lidocaine injection. We suggest that this temporary and simple laryngeal and tracheal anesthetic technique may have helped to break the perverse cycle of hyperactive glottal and supraglottal muscle contractions evident in each of these patients during phonation efforts. We discuss the possible sensorimotor mechanism of action of this therapeutic technique.     

Voice handicap index change following treatment of voice disorders

Outcome measurements of voice disorders is an important new area for both the evaluation of voice-disordered patients and evaluation of treatment efficacy. The Voice Handicap Index (VHI) measures the patient's perception of the impact of his or her voice-disorder. The VHI was used in this study to measure the changes of the patient's perception following treatment for four different voice disorders. The VHI showed a significant change following treatment for unilateral vocal fold paralysis, vocal cyst/polyp, and muscle tension dysphonia. Results of this paper indicate that the VHI is a useful instrument to monitor the treatment efficacy for voice disorders.     

The Prevalence of Childhood Dysphonia: A Cross-Sectional Study

There is only very limited information on the prevalence of voice disorders, particularly for the pediatric population. This study examined the prevalence of dysphonia in a large cohort of children (n = 7389) at 8 years of age. Data were collected within a large prospective epidemiological study and included a formal assessment by one of five research speech and language therapists as well as a parental report of their child's voice. Common risk factors that were also analyzed included sex, sibling numbers, asthma, regular conductive hearing loss, and frequent upper respiratory infection. The research clinicians identified a dysphonia prevalence of 6% compared with a parental report of 11%. Both measures suggested a significant risk of dysphonia for children with older siblings. Other measures were not in agreement between clinician and parental reports. The clinician judgments also suggested significant risk factors for sex (male) but not for any common respiratory or otolaryngological conditions that were analyzed. Parental report suggested significant risk factors with respect to asthma and tonsillectomy. These results are discussed in detail.     

Outcome of laryngeal manual therapy in four Dutch adults with persistent moderate-to-severe vocal hyperfunction: a pilot study

A relatively new management strategy for the treatment of voice disorders is the use of laryngeal manual therapy. The main purpose of the present pilot study is to document the outcome of vocal quality after a well-defined laryngeal manual therapy (LMT) program. Four Dutch professional voice users with a persistent moderate or severe muscle tension dysphonia were studied pretreatment (1 week before LMT) and posttreatment (1 week) after completion of manual therapy (25 sessions). These subjects had received several months of traditional voice therapy, without any success. To measure and compare, the effect of LMT objective and subjective assessment techniques were used. Perceptual voice assessment included a perceptual rating of the voice using the GRBAS scale. Furthermore, the vocal quality in this population was modeled by means of the Dysphonia Severity Index (DSI). All of the subjects selected for LMT showed improvement in perceptual vocal quality and DSI values. As the DSI is a weighted variable including aerodynamic and acoustic measures, small improvements (closer to 5) are very indicative of vocal quality improvement.¹ The use of LMT in professional voice users with persistent moderate-to-severe muscle tension dysphonia, especially in some subjects who have not responded to traditional voice therapy, is supported by this pilot study.     

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.     

Psychogenic dysphonia: Peeling back the layers

Resolution of psychogenic dysphonia is often quick and effortlessfor client and therapist alike. In such instances, the therapeutic interventions are simple and straightforward, insights are reached without difficulty, and once normal voice has been established, resumption of dysphonia or other psychosomatic symptoms rarely occurs. Sometimes, however, psychogenic dysphonia is extremely difficult to overcome, requiring considerable time, effort, and determination on the part of the client, coupled with confident, skilled persistence and psychotherapeutic insight from the therapist. In such cases one feels a sense of working through many complex layers before obtaining satisfactory voice or reaching an understanding of the psychogenic factors that precipitated onset and/or maintenance of the dysphonia.

Two cases that illustrate this involved process of peeling back the layers are presented. For resolution of severe psychogenic dysphonia, the therapist must be able to recognize and establish the complex relationship between the neurophysiological, intrapsychic, and interpersonal levels of function as they affect the client's voice and person, as a whole. This work requires considerable courage and skill on the part of the therapist to question, explore, change direction, and select alternative approaches. It is important that the problem can be resolved with a depth of understanding which is relevant for the client, and with due attention to the social context and wider systems of which he or she is a part.     

Psychogenic voice disorders and traumatic stress experience: a discussion paper with two case reports

Psychogenic dysphonia refers to loss of voice where there is insufficient structural or neurological pathology to account for the nature and severity of the dysphonia, and where loss of volitional control over phonation seems to be related to psychological processes such as anxiety, depression, conversion reaction, or personality disorder. Such dysphonias may often develop post-viral infection with laryngitis, and generally in close proximity to emotionally or psychologically taxing experiences, where "conflict over speaking out" is an issue. In more rare instances, severe and persistent psychogenic dysphonia may develop under innocuous or unrelated circumstances, but over time, it may be traced back to traumatic stress experiences that occurred many months or years prior to the onset of the voice disorder. In such cases, the qualitative nature of the traumatic experience may be reflected in the way the psychogenic voice disorder presents. The possible relationship between psychogenic dysphonia and earlier traumatic stress experience is discussed, and the reportedly low prevalence of conversion reaction (4% to 5%) as the basis for psychogenic dysphonia is challenged. Two cases are presented to illustrate the issues raised: the first, a young woman who was sexually assaulted and chose to "keep her secret," and the second, a 52-year-old woman who developed a psychogenic dysphonia following a second, modified thyroplasty for a unilateral vocal fold paresis.     

Combined-modality treatment of adductor spasmodic dysphonia with botulinum toxin and voice therapy

A combined-modality treatment program consisting of botulinum toxin injection (Botox) and voice therapy was used to treat 17 subjects diagnosed with adductor spasmodic dysphonia (ADD SD). Ten subjects with ADD SD served as the control and were given Botox only. Voice therapy after Botox injection was directed toward reducing the hyperfunctional vocal behaviors, primarily glottal overpressure at voice onset and anterior-posterior squeezing. The results indicated that subjects who underwent combined-modality treatment maintained significantly higher mean airflow rates for significantly longer periods. Moreover, there was a carryover effect in these patients when they received Botox only. Adductor spasmodic dysphonia is treated most effectively when intrinsic laryngeal muscle spasms are reduced or eliminated by Botox injection and extrinsic hyperfunctional vocal behaviors are treated with voice therapy     

Botulinum toxin in the treatment of recalcitrant mutational dysphonia

Mutational falsetto is the failure of the normal drop in vocal pitch at puberty. Voice therapy almost always achieves an appropriate pitch; however, in cases of failure, surgical treatment has also been recommended. We report a case of a 47-year-old man with an above-average fundamental frequency and a thin voice quality in the absence of any signs of androgen insufficiency. Laryngeal examination revealed atrophy of the vocalis muscle. Voice therapy was unsuccessful in achieving a stable voice. Injection of 15 units of botulinum toxin into each cricothyroid muscle initially resulted in aphonia, but the voice returned by 1 week. Average fundamental frequency was 84 Hz at 1 week, 104 Hz at 1 month, and 100 Hz at 1 year. We hypothesize that mutational dysphonia is an habitual dysfunction of the voice with inappropriate activation of the cricothyroid muscle and disuse of laryngeal adductor muscles. Temporary deactivation of the cricothyroid muscle enforces adoption of a more appropriate vocal mechanism. Botulinum toxin as an adjunct to voice therapy should be considered before surgical alteration of the glottis in patients with recalcitrant mutational falsetto.     

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.     

Vocal stability in functional dysphonic versus healthy voices at different times of voice loading

Functional (nonorganic) dysphonia is often characterized by vocal instability. The purpose of the prospective study was to examine whether there is a difference in vocal instability of functional dysphonic voices compared with healthy ones, this means whether electroglottographic perturbation values differ (1) between healthy and dysphonic voices and (2) between two subgroups of the dysphponic voices (hpertonic and hypotonic dysphonic voices). Twenty-three patients with hypertonic functional dysphonia, 9 with hypotonic functional dysphonia and 31 healthy nonsmokers, were each examined electroglottographically before (Ex 1), immediately after (Ex 2), and 1 hour after (Ex 3) voice loading. Perturbations of frequency, amplitude, quasi-open-quotient, and contact-index were calculated from the EGG signal. At all three times of examination, hypertonic dysphonic voices showed higher perturbations than healthy voices, and they had higher perturbations than hypotonic dysphonic voices before and 1 hour after voice loading. Hypotonic dysphonic voices showed higher perturbations than healthy voices only 1 hour after voice loading. Voice loading induced different reactions in dysphonic voices: Some voices showed increased perturbations, and others exhibited normal or even decreased perturbation immediately after voice loading. Examination of electroglottographic-derived perturbations immediately after voice loading seems not to be useful. Differentiation of hypertonic and hypotonic dysphonic voices was possible with an estimated sensitivity of 88.9% and a specificity of 87.0% by using the sum of the amplitude-perturbation and the quasi-open-quotient-perturbation measured before voice loading.     

The irritable larynx syndrome

Muscular tension dysphonia, episodic laryngospasm, globus, and cough may be considered to be hyperfunctional laryngeal symptoms. Suggested etiological factors for these symptoms include gastroesophageal reflux, psychological problems, and/or dystonia. We propose a unifying hypothesis that involves neural plastic change to brainstem laryngeal control networks through which each of the above etiologies, plus central nervous system viral illness, can play a role. We suggest that controlling neurons are held in a "spasm-ready" state and that symptoms may be triggered by various stimuli. Inclusion criteria for the irritable larynx syndrome are episodic laryngospasm and/or dysphonia with or without globus or chronic cough; visible or palpable evidence of tension or tenderness in laryngeal muscles; and a definite symptom-triggering stimulus. thirty-nine patients with irritable larynx syndrome were studied. Gastroesophageal reflux was felt or proven to play a major role in a large number of the group (>90%), and about one third were deemed to have psychological causative factors. Viral illness seemed quite prevalent, with one third of patients able to relate the onset of symptoms to a viral illness that we feel might lead to central nervous system changes. Our proposed hypothesis includes a mechanism whereby acquired plastic change to central brainstem nuclei may lead to this form of hyperkinetic laryngeal dysfunction. It gives structure and reason to an array of therapy measures and suggests direction for basic research.     

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.     

Neurovegetative symptoms and complaints before and after voice therapy for nonorganic habitual dysphonia

In a previous study, female patients in all age categories with a nonorganic dysphonia were found to report significantly more autonomic symptoms and complaints than healthy controls. This could not be confirmed for the male subgroup. The present study is to corroborate and nuance this observation by investigating larger groups, and to determine if, after voice therapy, the number of autonomic symptoms and complaints-particularly those ones that have no obvious relation to voice function-decreases. It is a prospective study with a matched control group; 184 patients with nonorganic dysphonia and 126 normal controls answered a questionnaire of 46 questions with 3 subsets and a consistency control. One hundred and one patients received functional voice therapy and completed the questionnaire before and after treatment. A matched control group of 42 normal subjects also filled in the questionnaire two times, with an interval of about 6 months. Neurovegetative symptoms and complaints-voice related and not related-are reported in highly significant excess by patients (especially but not exclusively females) with habitual nonorganic voice disorder. After therapy, there is a highly significant reduction in the number of autonomic symptoms and complaints (related or not related to voice), to such an extent that patients report on average no more general neurovegetative symptoms and complaints than healthy controls (even less). The number of neurovegetative symptoms and complaints connected with voice function is also strongly reduced in patients after therapy, but remains in significant excess when compared with controls.     

Use of acupuncture for the treatment of adductor spasmodic dysphonia: a preliminary investigation

Ten subjects with adductor spasmodic dysphonia participated in a study examining the effects of an acupuncture treatment protocol on their voice disorder. Treatment consisted of eight sessions, and it was designed and performed by two physicians certified in acupuncture. Voice characteristics were evaluated pretreatment and posttreatment using the CSL Motor Speech Profile (MSP), Unified Spasmodic Dysphonia Rating Scale, and Voice Handicap Index (VHI). Subjects also answered a posttreatment questionnaire regarding their experience. Significant pretreatment and posttreatment differences occurred for some MSP measures. Significant differences were found on all three subtests of the VHI, and the average total scores pretreatment and posttreatment differed by 17 points (considered significant according to VHI standardization). Seven of 10 subjects reported improvements in voice production, although expert raters did not detect perceptual changes in voice quality. Possible reasons for the discrepancies between objective measures and self ratings, and implications for further research, are discussed.     

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.     

Psychological correlates of functional dysphonia:An investigation using the Minnesota multiphasic personality inventory

Abnormal psychological factors have been implicated in the development of functional dysphonia (FD). This investigation describes the personality and psychological characteristics of 25 female subjects who had received the diagnosis of FD. In all subjects symptoms were resolved after voice therapy. While vocally asymptomatic, these remitted subjects with FD completed the Minnesota Multiphasic Personality Inventory (MMPI), an objective personality questionnaire. When compared with a medical outpatient control group, the results showed that subjects with FD scored significantly higher on 7 of 10 clinical scales, suggesting an elevated degree of emotional maladjustment. A stepwise logistic discriminant analysis identified 2 clinical scales that provided valuable discriminatory power between the two groups. Scale I (Hs-hypochondriasis), which measures the number and type of reported somatic complaints, and scale 7 (Pt-psychasthenia), a measure of diffuse anxiety, discriminated the groups with 88% sensitivity and 89% specificity. The results suggested that in spite of symptom improvement after voice therapy, the subjects with FD continued to exhibit poor levels of adaptive functioning, which may represent trait-like vulnerability. The clinical implications of these results for voice practitioners are discussed.