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.     

Acoustic Analysis of Voice Quality with or without False Vocal Fold Displacement After Cordectomy

Conventional cordectomy by means of a laryngofissure is one of the therapeutic options for treatment of early glottic cancer. To improve the poor voice quality related to this kind of operation, many authors have developed different techniques to repair the mucosal defect. We analyzed voice quality acoustically and compared it after cordectomy alone and after cordectomy with the reconstruction of the vocal cord in a group of 14 patients affected by T1 glottic carcinoma. All the patients underwent postoperative speech therapy. Three patients who underwent cordectomy with reconstruction showed the presence of diplophonia, while two patients without reconstruction showed the presence of bitonality. The differences of the acoustic parameters (jitter, shimmer, harmonic-to-noise ratio) between the two groups of patients were not statistically significant. Reconstruction of the vocal cord does not seem to improve voice quality after cordectomy even in combination with postoperative speech therapy.     

The Relationship Between VHI Scores and Specific Acoustic Measures of Mildly Disordered Voice Production

This study was designed to examine the relationship between the Voice Handicap Index (VHI) and acoustic measures of voice samples common in clinical practice. Fifty participants, 38 women and 12 men, ranging in age from 19 to 80 years, with a mean age of 49 years, served as participants. Of these 50 participants, 17 participants could be included in the acoustic analysis of voice based on measures of error calculated with the TF32 software. All participants completed the VHI and provided voice samples including three trials of the sustained vowel /A/ at a comfortable loudness level as well as a connected speech sample consisting of the Zoo Passage. Acoustic measures were made with TF32 and Cool Edit software and included fundamental frequency, jitter %, shimmer %, signal-to-noise ratio, mean root-mean-square intensity, fundamental frequency standard deviation, aphonic periods, and breath groups. Results indicate that these measures were not predictive of overall VHI score, and no cohesive or predictable pattern was identified when comparing individual measures with overall VHI or with each subscale item. Likely contributions to this lack of correlation and subsequent clinical implications are discussed, as well as the direction for further research.     

Voice-over: Perceptual and Acoustic Analysis of Vocal Features

Voice-overs are professional voice users who use their voices to market products in the electronic media. The purposes of this study were to (1) analyze voice-overed and non-overed productions of an advertising text in two groups consisting of 10 male professional voice-overs and 10 male non-voice-overs; and (2) determine specific acoustic features of voice-over productions in both groups. A na?ve group of listeners were engaged for the perceptual analysis of the recorded advertising text. The voice-overed production samples from both groups were submitted for analysis of acoustic and temporal features. The following parameters were analyzed: (1) the total text length, (2) the length of the three emphatic pauses, (3) values of the mean, (4) minimum, (5) maximum fundamental frequency, and (6) the semitone range. The majority of voice-overs and non-voice-overs were correctly identified by the listeners in both productions. However voice-overs were more consistently correctly identified than non-voice-overs. The total text length was greater for voice-overs. The pause time distribution was statistically more homogeneous for the voice-overs. The acoustic analysis indicated that the voice-overs had lower values of mean, minimum, and maximum fundamental frequency and a greater range of semitones. The voice-overs carry the voice-overed production features to their non-voice-overed production.     

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.     

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.     

Common Practices of Voice Therapists in the Evaluation of Patients

This study surveys voice therapists regarding common diagnostic practices in patients referred for therapy with the diagnosis of muscle tension dysphonia (broadly defined as the "hyperfunctional" component of the dysphonia). Through postings on the e-mail list of the ASHA special interest division on voice, speech pathologists with at least 3 years' experience in stroboscopy and acoustic instrumentation were invited to complete the survey. Results from 53 completed surveys demonstrated that voice quality and patient self-perception are the sole assessments performed by all therapists. Voice quality, observation of body posture and movement, and probing the patient's ability to alter voice production are each significantly more likely to be performed than the more objective stroboscopic, acoustic, aerodynamic, and EGG assessments. Further, the tasks of defining specific therapy session goals and helping the patient to achieve a particular target skill are considered best served by measures of vocal quality, observation of body position and movement, and judging the patient's ability to alter voice production. For definition of the overall therapy goal, stroboscopy and patient perception scales are added to all of the subjective assessment measures as being important. Acoustic data are considered most important for patient reinforcement and outcomes assessment. Implications of these findings are discussed, and topics for further exploration are identified.     

Current and Emerging Concepts in Muscle Tension Dysphonia: A 30-Month Review

The modern theory of hoarseness is that there are multifactorial etiologies contributing to the voice problem. The hypothesis of this study is that muscle tension dysphonia is multifactorial with various contributing etiologies. METHODS: This project is a retrospective chart review of all patients seen in the Voice Speech and Language Service and Swallowing Center at our institution with a diagnosis of muscle tension (functional hypertensive) dysphonia over a 30-month period. A literature search and review is also performed regarding current and emerging concepts of muscle tension dysphonia. RESULTS: One hundred fifty subjects were identified (60% female, 40% male, with a mean age of 42.3 years). Significant factors in patient history believed to contribute to abnormal voice production were gastroesophageal reflux in 49%, high stress levels in 18%, excessive amounts of voice use in 63%, and excessive loudness demands on voice use in 23%. Otolaryngologic evaluation was performed in 82% of patients, in whom lesions, significant vocal fold edema, or paralysis/paresis was identified in 52.3%. Speech pathology assessment revealed poor breath support, inappropriately low pitch, and visible cervical neck tension in the majority of patients. Inappropriate intensity was observed in 23.3% of patients. This set of multiple contributing factors is discussed in the context of current and emerging understanding of muscle tension dysphonia. CONCLUSIONS: Results confirm multifactorial etiologies contributing to hoarseness in the patients identified with muscle tension dysphonia. An interdisciplinary approach to treating all contributing factors portends the best prognosis.     

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.