Aerodynamic and Acoustic Characteristics of Voice in Prader-Willi Syndrome

Prader-Willi syndrome (PWS) is a multisystem disorder caused by DNA abnormalities involving chromosome 15. Major characteristics are infant hypotonia, hypogonadism, mental retardation, a short stature, atypical facial appearance, and the onset of obesity due to insatiable hunger in early childhood. Also, speech and language abnormalities have been reported including voice disorders. These have seldom been studied in detail, however. This paper reports the results of an acoustic and aerodynamic investigation of the voice in 22 individuals with PWS. Two age groups were distinguished, a group of children [chronological age (CA) 6 years, 7 months through 11 years, 7 months; total intelligence quotient (TIQ) 40-88] and a group of adolescents and adults (CA 17 years, 1 month through 29 years, 5 months; TIQ 41-94). Both aerodynamic and acoustic parameters were obtained and compared with normative data from the Belgian Study Group on Voice Disorders. It was found that voice difficulties do commonly occur in individuals with PWS including impairment of frequency levels, voice quality, and poor aerodynamic capabilities.     

A study of the effectiveness of voice therapy in the treatment of 45 patients with nonorganic dysphonia

Forty-five patients diagnosed as having nonorganic dysphonia were assigned in rotation to 1 of 3 groups. Patients in group 1 received no treatment and acted as a control group. Patients in groups 2 and 3 received a program of indirect therapy and direct with indirect therapy, respectively. A range of qualitative and quantitative measures were carried out on all patients before and after treatment to evaluate change in voice quality over time. Results revealed a significant difference between the 3 treatment groups in the amount of change for the voice severity, electrolaryngograph, and shimmer measurements and on ratings provided by a patient questionnaire (P<0.05). However, other measures failed to show significant differences between the 3 groups. Most of the patients (86%) in group 1 showed no significant change on any of the measures. Some patients in treatment group 2 (46%) showed significant change in voice quality. Fourteen out of 15 patients (93%) in treatment group showed significant changes in voice quality.     

Vocal Improvement After Voice Therapy in Unilateral Vocal Fold Paralysis

Unilateral vocal fold paralysis (UVFP) is associated with changes in acoustic and aerodynamic voice measurements and can have a significant impact on a patient's quality of life. Few objective data regarding the efficacy of voice therapy for UVFP exist. The aim of this study was to retrospectively analyze voice modifications in a group of patients with UVFP before and after voice therapy. Forty patients with UVFP of different etiology were included in the study. Each subject had voice therapy with an experienced speech/language pathologist twice a week; the mean number of sessions was 12.6. A multidimensional assessment protocol was used; it included videoendoscopy, the maximum phonation time (MPT), the GIRBAS scale, spectrograms and a perturbation analysis, and the Voice Handicap Index (VHI). Pre- and posttreatment data were compared by means of the Wilcoxon and Student's t tests. A complete glottal closure was seen in 8 patients before voice therapy and in 14 afterward. Mean MPT increased significantly. In the perceptual assessment, the difference was significant for five out of six parameters. A significant improvement was found on spectrographic analysis; as for perturbation analysis, the differences in jitter, shimmer, and noise-to-harmonic ratio values were significant. VHI values showed a clear and significant improvement. A significant improvement of voice quality and quality of life after voice therapy is an often reached and reasonable goal in patients with UVFP.     

Voice field measurements—a new method of examination: the influence of hearing on the human voice

There are various methods to evaluate voice parameters. Original software was used to assess the voice quality by the staff of AUDIO-Fon centr Brno, Czech Republic. A group of hereditary deaf persons was examined. Deaf persons have all of the biological conditions to make voice except for the possibility of acoustic feedback. We examined the voices of 35 persons (20 men and 15 women) with hereditary profound hearing impairments, and we compared voice parameters with the voice of intact persons. To measure we used special software called voice field measurements (VFMs). The program graphically records voice frequency and intensity. VFM is an objective method that enables the assessment of basic physical voice characteristics. It is suitable for the examination of both intact and disturbed voice. The voice of the deaf has a higher basic voice frequency in men as well as in women. This type of voice production, ie, childlike voice, which is fixed only by a motor stereotype, is much more demanding for a mature larynx. Hearing influences both the voice development and speech production. The voice of persons with hearing impairments has a higher basic voice frequency regardless of their sex. This type of voice production, which is fixed only by a motor stereotype, ie, child voice, is much more demanding for a larynx of an adult. Thus, phonation of deaf people is more demanding and their voice production needs greater effort. Deaf people, despite an intact phonic apparatus, cannot produce more than one type of voice. They cannot modulate their voices concerning the frequency and dynamics. They cannot change their voices continually. The voice is limited in both of these parameters (frequency and dynamics). If a deaf person wants to change a voice characteristic, it is possible only by discontinuous changes-"skipping."     

Clinical Analysis of Voice Change as a Parameter of Premenstrual Syndrome

We have evaluated the relationship between voice change and premenstrual syndrome (PMS) by comparing acoustic measurements made during the follicular phase and the premenstrual phase. Twenty-eight women were followed for 2 months for this study. Each participant was asked to produce an /a/ sound for 5 seconds at the midfollicular phase of the menstrual cycle and then 2-3 days before menstruation. Each voice sample was stored and analyzed by the Dr. Speech Science program. The voice data collected from all subjects during the two phases were compared. After that, the subjects were divided into a PMS-positive and PMS-negative group according to the criteria cited in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV); the voice data from each group were compared separately between the two phases. There was no significant difference in the acoustic parameters between the two phases in all subjects (N = 28). In the PMS-positive group (N = 16), jitter was significantly increased during the premenstrual phase compared to the follicular phase (p = 0.048). The patient's PMS score was not correlated with the severity of voice change. We conclude that the change of voice parameter was objectively identified in the PMS-positive group, therefore more careful voice habituation is required during the premenstrual phase in that group.     

The Effectiveness of Group Therapy for Students With Mild Voice Disorders: A Controlled Clinical Trial

Previous studies of students studying to be teachers have indicated that these students commonly have voice disorders. Ideally, voice disorders should be treated before students start their work as teachers, but the resources for this treatment are often limited. This study examines whether group voice therapy is effective for teacher students. Accordingly, 20 teacher students with mild voice disorders received group voice therapy (in three small groups), whereas 20 students with similar voice disorders served as a control group and consequently did not receive voice therapy. Two out of three outcome measures (perceptual evaluation of voice quality and a questionnaire on the occurrence of vocal symptoms) indicated significant changes in the treatment group compared with the control group. No differences between groups were noted in the laryngeal status. The results suggest that group voice therapy seems to be an effective method to treat students with mild voice disorders.     

Objective and Subjective Evaluation of Voice Quality in Multiple Sclerosis

The aim of this comparative, controlled, cross-sectional study is to evaluate the voice quality in patients with multiple sclerosis (MS) by subjective and objective methods. Female patients with MS (n=27) and age- and sex-matched healthy controls (n=27) were included in this study. Vocal functions were evaluated by a multidimensional set composed of videolaryngostroboscopic examination, acoustic analysis, and subjective measurements (GRBAS and "Voice Handicap Index"). Jitter percent, shimmer percent, and soft phonation index (SPI) values were higher in MS patients compared to controls (Jitt, P=0.001; Shim, P=0.033; SPI P<0.0001). Maximum phonation time was significantly shorter for MS patients compared to controls (P<0.0001). Stroboscopic examination revealed that 16 out of 27 MS patients have a "posterior chink" as glottic closure pattern with higher SPI values (40%). Noise to harmonic ratio (NHR) and mean fundamental frequency (F0) values were similar for MS and control groups (NHR, P=0.737; F0, P=0.976). In this study, most of the MS patients had dysphonia due to weakness of voice. MS tends to worsen acoustic parameters including fundamental frequency, SPI, and jitter values. These results are consistent with the more asthenic voice quality observed in MS group.     

Intensive voice treatment in parkinson disease: Laryngostroboscopic findings

As part of ongoing research to investigate and document the efficacy of intensive voice therapy to improve functional communication in patients with idiopathic Parkinson disease, 45 patients were enrolled in a controlled, randomized, prospective study. Pre- to posttreatment comparisons are presented here on 22 of those patients who underwent laryngeal imaging examination. Of the 22 patients, 13 patients received intensive therapy aimed at increasing vocal and respiratory effort (VR), whereas nine received intensive therapy aimed at increasing respiratory effort (R) only. All patients had a pretreatment evaluation that included two (but sometimes only one) voice recordings and an otolaryngologic examination with laryngostroboscopy. At the completion of 4 weeks of therapy (16 sessions), two voice recordings were made, and laryngostroboscopy was again performed. The pre- and posttherapy videolaryngostroboscopy tapes were then randomized and rated by four judges. Raters' findings were then compared with vocal intensity measured before and after therapy. The VR therapy group showed improvements on laryngostroboscopic variables: less glottal incompetence and no significant change in supraglottal hyperfunction after therapy. No differences were observed in the R-only group. The mean intensity increase in the VR therapy group was 12.5 dB, compared with a decrease of 1.9 dB in the R-only group. These findings suggest that in patients with Parkinson disease, intensive therapy focusing on phonatory effort improves adduction of the vocal folds as assessed by laryngostroboscopy. Differences in laryngeal function in these patients observed with fiberoptic laryngoscopy and rigid telescopic laryngoscopy are discussed.     

Vocal quality characteristics in children with cleft palate: a multiparameter approach

The main purpose of the present study was to examine the vocal quality and to investigate the effects of gender on vocal quality in 28 children with a unilateral or bilateral cleft palate. In this study, the vocal quality was determined using videolaryngostroboscopic and perceptual evaluations, aerodynamic, voice range, acoustic, and dysphonia severity index (DSI) measurements. The DSI is based on the weighted combination of four voice measurements and ranges from +5 to -5 for, respectively, normal and severely dysphonic voices. Additional objectives were to compare the vocal quality characteristics of children with cleft palate with the available normative data and to investigate the impact of the cleft type on vocal quality. Gender-related vocal quality differences were found. The male cleft palate children showed an overall vocal quality of +0.62 with the presence of a perceptual slight grade of hoarseness and roughness. The female vocal quality had a DSI value of +2.4 reflecting a perceptually normal voice. Irrespective of the type of cleft, all subjects demonstrated a significantly lower DSI-value in comparison with the available normative data. The results of the present study have provided valuable insights into the vocal quality characteristics of cleft palate children.     

Voice Change in Seasonal Allergic Rhinitis

Voice problems are seldom reported in pollen allergy, although the allergic reaction involves the entire airways. The objective of this study was to investigate voice dysfunction during the pollen season in patients with allergic rhinitis. Thirty patients with verified birch pollen allergy and 30 controls were investigated twice, during the pollen season and outside the pollen season. Both times they scored respiratory and voice symptoms, the latter with the validated questionnaire Voice Handicap Index (VHI), and performed standardized voice recordings. These recordings were analyzed in a controlled manner by a professional voice therapist. During the allergy season, patients reported more respiratory and voice symptoms compared with controls. Those with blinded scored voice dysfunction scored their voice quality during springtime as 31 mm (95% confidence interval [CI] 20-42 mm), compared with 13 mm (95% CI 6-21 mm for participants without voice dysfunction (P<0.01). Furthermore, the group with experienced voice dysfunction scored significantly higher on the VHI in the functional and physical domains and in the total VHI score. Although voice problems during the pollen season are rarely discussed, in allergic rhinitis the larynx may also be involved. These findings support that some patients experience voice change, an experience which can be objectively confirmed.     

Communicative Suitability of Voice Following Radiotherapy for T1 Glottic Carcinoma: Testing the Reliability of a Rating Instrument

The objective of the study was to determine whether a communicative suitability rating instrument could be used in a meaningful way to assess functionality of voice following radiotherapy for T1 glottic cancer. Seventeen naive listeners judged the suitability of voice of a patient group with T1 glottic carcinoma (n = 20) just before treatment, a group of patients (n = 40) after radiotherapy, and a matched control group (n = 20) of normal speakers. Listeners rated suitability on a 10-point scale for 10 speaking situations, which supposedly make different demands. In order to validate scores on communicative suitability, ratings were related to perceptual voice quality evaluations and videolaryngostroboscopic evaluations. Results indicate that the concept of measuring listener judgments of communicative suitability of voice is basically sound. Raters are reliable and can discriminate between groups of normal and pathological voices. Patients with T1 glottic carcinoma (assessed before the start of treatment) have on average the least suitable voices. Following radiotherapy suitability is, on average, improved, but does not approach the suitability of normal voices. Ratings on communicative suitability were clearly related to perceptual voice quality aspects and videolaryngostroboscopic evaluations. A subset of three communicative suitability rating scales is recommended as part of the protocol for evaluating voice outcome after radiotherapy for early glottic cancer, besides perceptual evaluation of voice quality by trained and naive raters, videolaryngostroboscopy, acoustical analyses, and self-ratings of vocal performance.     

Efficacy of a Behaviorally Based Voice Therapy Protocol for Vocal Nodules

The aim of this study was to assess the effects on vocal function of voice therapy for vocal nodules. Perceptual and physiological progressive changes were examined during a strictly structured, behaviorally based voice therapy protocol in which 11 women with vocal nodules participated. Randomized audio recordings from pretherapy and from each of the therapy approaches (vocal hygiene, respiration, direct facilitation, carryover) were used for perceptual evaluations. Six speech-language pathologists rated ten voice quality parameters. Two evaluation procedures were performed and compared. Interlistener reliability was sufficiently high in both tests. Significant effects of therapy were found for decreased overall dysphonia, press, instability, gratings, roughness, vocal fry, and "scrape." Nonsignificant group effects were found for breathiness, aphonic instances, and lack of sonority. No significant parameter changes occurred between baseline assessment and the completion of the initial (vocal hygiene) phase of therapy. Significant changes were found following the direct facilitation and respiration phases of therapy. Videostroboscopic evaluations made by two laryngologists showed that in no case were the nodules completely resolved. However, the nodules had decreased in size and edema was reduced after therapy for all clients, but one. Combined results suggest: (1) Alterations in vocal function were reflected in perceptual parameters, and (2) the voice therapy had a positive effect on voice quality, vocal status, and vocal function for the majority of the vocal nodule clients.     

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.     

A Novel Treatment for Hypophonic Voice: Twang Therapy

A hypophonic voice, characterized perceptually as weak and breathy, is associated with voice disorders such as vocal fold atrophy and unilateral vocal fold paralysis. Although voice therapy programs for hypophonia typically address the vocal folds or the sound source, twang voice quality was examined in this study as an alternative technique for increasing vocal power by altering the epilarynx or the sound filter. OBJECTIVE: This study investigated the effect of twang production on physiologic, acoustic, and perceived voice handicap measures in speakers with hypophonia. DESIGN/METHODS: This prospective pilot study compared the vocal outcomes of six participants with hypophonia at pre- and posttreatment time points. Outcome measures included mean airflow rate, intensity in dB sound pressure level (SPL), maximum phonation time, and self-report of voice handicap. RESULTS: All subjects improved in at least three of the four vocal outcome measures. Wilcoxon signed-rank test of paired differences revealed significant differences between pre- and posttherapy group means for airflow rate, SPL, and Voice Handicap Index scores. CONCLUSION: The twang voice quality as a manipulation of the sound filter offers a clinical complement to traditional voice therapies that primarily address the sound source.     

Coping strategies, personality, and voice quality in patients with vocal fold nodules and polyps

Emotional state affects the physiological mechanism involved inphonation. Differences in acoustical parameters of the voice under stress have been attributed to the coping mechanism used, which is based on the individual's perception of the situation. This study examines the relationship between coping strategies, personality, and voice in female subjects, ranging in age from 19.3–55.7 years, diagnosed with vocal nodules or polyps. The differences between coping strategies and personality are examined and compared with another group with no history of voice pathology. The relationship of personality and coping strategies to voice quality variables is reported. Results show that patients use emotional coping strategies more and cognitive coping strategies less than the comparison group. Type of voice pathology was found to be related to dominance, and a number of coping and personality variables were found to correlate significantly with voice quality.     

An investigation of the Voice Handicap Index with Speakers of Portuguese: Preliminary data

Although the Voice Handicap Index (VHI) has been recognized as a useful tool for quantifying American English speakers' perceived consequences of voice disorder, it has not yet been widely applied in the clinic to study dysphonic patient populations, or tested with a normally speaking population. The purpose of this investigation was to obtain information about the VHI in a group of Portuguese speakers with voice complaints compared with an age- and gender-matched group of speakers without voice complaints. The results demonstrate that speakers with voice complaints have overall VHI total scores significantly higher than speakers without voice complaints (p < 0.001). This is also true for all VHI subscores in the emotional (p < 0.001), functional (p < 0.05), and physical (p < 0.001) domains. So, the assumption that a group with voice complaints has higher voice handicap impact than the matched control comparison group is justified for Portuguese speakers.     

Voice Therapy Improves Quality of Life in Age-Related Dysphonia: A Case-Control Study

The objective of the study is to determine the efficacy of voice therapy in the treatment of age-related dysphonia. The study was conducted using a retrospective case-control chart review. The medical records of 54 patients older than 60 years diagnosed with age-related dysphonia without complicating diagnoses were reviewed. Patients who chose to undergo voice therapy were grouped as cases. Patients who chose not to undergo voice therapy were grouped as controls. The voice-related quality of life (VRQOL) measure was used to measure outcomes before and after treatment in cases and at a minimum 2-month follow-up in controls. Of the 54 patients, 19 (10 female, 9 male; mean age 73 years) chose to undergo voice therapy and filled in >1 VRQOL questionnaire. Six patients (3 female, 3 male; mean age 66 years) chose not to undergo voice therapy and filled in >1 VRQOL questionnaire. The 19 cases experienced a mean improvement in VRQOL score of 19.21 (2-tailed matched pairs t test P=0.00038) after a mean of 4.1 voice therapy sessions and 5.1 months. The six controls experienced a mean change in VRQOL score of 0.42 (2-tailed matched pairs t test P=0.96) after a mean of 3.3 months. Voice therapy leads to statistically significant improvement in the VRQOL life in elderly patients with age-related dysphonia. It is an efficacious noninvasive therapy for this disease.     

The Relationship Between Perceptual Evaluation and Objective Multiparametric Evaluation of Dysphonia Severity

SUMMARY: The purpose of this study was to investigate the usefulness of the Dysphonia Severity Index (DSI) as an objective multiparametric measurement in assessing dysphonia. The DSI was compared with the score on Grade of the GRBAS scale. Investigated was also whether the DSI is related to severity of dysphonia, which was represented by different diagnosis groups. Furthermore, it was investigated whether the DSI can differentiate between a group of patients and a control group. A total of 294 patients with different voice pathologies were included. A control group consisted of 118 volunteers without any voice complaints. The voices of all participants were perceptually evaluated on Grade, and the DSI was measured. The groups of patients with voice complaints have a lower DSI and higher scores on Grade than the control group. The DSI was significantly lower when the score on Grade was higher. The DSI discriminates between patients with nonorganic voice disorders, vocal fold mass lesions, and vocal fold paresis/paralysis. To determine whether the DSI discriminates between patients and controls, the sensitivity and specificity for different DSI cutoff points were calculated. With a DSI cutoff of 3.0, maximum sensitivity (0.72) and specificity (0.75) were found. We conclude that the DSI is a useful instrument to objectively measure the severity of dysphonia.