Investigation of the Immediate Effects of Humming on Vocal Fold Vibration Irregularity Using Electroglottography and High-speed Laryngoscopy in Patients With Organic Voice Disorders

The Immediate Impact of Targeted Exercises on Voice Characteristics in Female Speakers With Phonotraumatic Vocal Fold Lesions

OBJECTIVE

To examine the immediate impact of 30 minutes of targeted voice exercises on measures of vocal function and lesion characteristics in female speakers with phonotraumatic vocal fold lesions (PVFLs).

STUDY DESIGN

Prospective cohort study.

METHOD

Twenty-nine (n = 29) female subjects with PVFLs completed a 30 minutes targeted voice exercise protocol and a multidimensional voice analysis was conducted immediately pre and post-exercise. Analysis included expert perceptual evaluation of connected speech and stroboscopy recordings, instrumental analysis by selected aerodynamic and acoustic parameters, and self-ratings of effort and vocal function by participants. The direction and magnitude of the change from pre- to post-exercise for each individual across parameters was assessed against a Minimal Clinically Important Difference criteria.

RESULTS

Variability was observed among participants in their response to exercise and across parameters. Multidirectional change in function was demonstrated across instrumental parameters, with observations of both improvement and decline. The most consistent change observed was a reduced PTP post-exercises for 38% of participants (n = 11), and the greatest magnitude of change was observed in aerodynamic measures of airflow and pressure, and the acoustic parameter semitone range. Variability in the direction of change across instrumental measures was observed for 24% of participants (n = 7), while consistent improved function was seen for 45% (n = 13), declined function for 17% (n = 5) and no change for 14% (n = 4). Participant's self-reported effort and function post-exercise was also multidirectional, with the greatest number reporting improvement. Comparatively little change was observed in perceptual evaluation of speech and stroboscopy recordings. Findings suggest that individuals with all lesion types, sizes and liabilities have the potential to improve vocal function immediately post-exercises according to instrumental measures, with the greatest magnitude of change observed in participants with large lesions. Although participants' characteristics did not differentiate, those with nodules or polyps tended to report improvement in function and reduced effort post-exercise, whereas those with a diagnosis of pseudocyst/s or a unilateral lesion appeared to report no change or declined function.

CONCLUSION

Change in measures of vocal function was observed in female speakers with PVFLs immediately following a 30 minutes targeted exercises protocol. Many demonstrated improvement but a high degree of variability was observed in the way speakers respond, and it is likely an individual's response is influenced by a range of factors. Self-rating scales, along with key instrumental parameters sensitive to the presence of PVFLs, may prove most useful in tracking initial change in the immediate and short-term duration in this population, and in assessing stimulability and candidacy for therapy. Further exploration is warranted of stimulability for immediate and cumulative change to achieve sustained improvement in function and efficiency across time.

Semi-occluded Nasal Tract Exercises (SONTEs): Nasal Tube in Water Exercises Using Nasal Consonants

OBJECTIVE

This study analyzes the effects of the vocal exercises called semi-occluded nasal tract exercises (SONTEs), which were carried out with a new appliance that extends the nasal cavity as a part of the vocal tract. The acoustic, aerodynamic and electroglottographic (EGG) measurements were compared with those of the traditional semi-occluded vocal tract exercises (SOVTEs) of phonation in water.

METHODS

In this study, 34 women were randomly asked to perform phonation in water for 5 min through the nasal and oral routes with the sounds /m/ and /ɔ/, respectively, using a tube with a submersion depth of 5 cm. The acoustic, aerodynamic and EGG measurements before and after the exercises were analyzed using the appropriate statistical methods.

RESULTS

No significant difference was found in the time and frequency domain parameters before and after the exercises, except for the amplitude perturbation quotient (APQ) values, which decreased after both exercises. In addition, there was no significant difference in any aerodynamic parameters before and after the exercises, but the mean SPL values significantly increased after both exercises. The oral and nasal peak inspiratory flow rates increased after both exercises, but the increase peaked after the SONTEs implementation. As expected, the EGG-jitter and EGG-periodicity values had a reciprocal interaction with each other, while differences were observed between the values of the vocal fold movements measured in both exercises.

CONCLUSIONS

SONTEs may be as effective as the conventional SOVTEs because it made tube phonation into water possible through artificial extension of the nasal cavity and increased the resonant effect by using the positive effects based on the principles of SOVTEs.

Symptom Expression Across Voiced Speech Sounds in Adductor Laryngeal Dystonia

OBJECTIVES

Differential diagnosis for adductor laryngeal dystonia (AdLD) is often carried out by comparing symptom expression during sentences with either all voiced or voiced and voiceless consonants. However, empirical research examining the effects of phonetic context on symptoms is sparse. The purpose of this study was to examine whether symptom probabilities varied across voiced speech segments in an all-voiced sentence, and whether this variability was systematic with respect to phonetic features.

METHODS

Eighteen speakers with AdLD read aloud a sentence comprised entirely of voiced speech sounds. Speech segment boundaries and AdLD symptoms (phonatory breaks, frequency shifts, and creak) were labeled separately, and speech segments were coded as symptomatic or asymptomatic based on their temporal overlap. Generalized linear mixed effects models with a binomial outcome variable were used to compare the probability of symptom expression across: 1) all speech segments in the sentence, and 2) four speech sound classes (vowels, approximants, nasals, and obstruents).

RESULTS

Significant symptom variability was found across voiced speech segments in the sentence. Furthermore, the estimated probability of a symptom occurring on vowels and approximants was significantly greater than that of nasals and obstruents.

CONCLUSION

These results indicate that AdLD symptoms are not uniformly distributed across voiced speech segments with systematic variation across speech sound classes.To explain these findings, future work should investigate how the complex interactions between the vocal tract articulators and glottal configurations may influence symptom expression in this population.

Clinician and Patient Perception of a Voice Therapy Program Utilizing a Variably Occluded Face Mask: A Pilot Study

OBJECTIVE

The purpose of this investigation was to assess clinician and patient feedback about voice therapy using a variably occluded face mask (VOFM) and to determine if voice therapy augmented via a VOFM would result in favorable changes in patient self-perceived handicap, as well as acoustic and aerodynamic measures.

METHODS/DESIGN

This pilot study used a prospective, pre-post single group design. Eleven patients with dysphonia due to primary muscle tension dysphonia (8) or benign vocal fold lesions (3) were recruited. Data collected included patient and clinician feedback of voice therapy using a VOFM, voice handicap index (VHI)-10, acoustic and aerodynamic measures. Data were collected before treatment (baseline) and 1-week post-therapy. Wilcoxon signed-rank tests were used to compare data pre- and post-therapy.

RESULTS

Statistically significant improvement was observed for the VHI-10 with a median delta of -7. Clinician feedback generally reported that patients liked the VOFM, using the VOFM within the first two sessions of therapy, and within less than 10 min of use. All clinicians ranked the conversation level of the hierarchy as the most effective level. Three themes emerged from the Therapy Feedback Form: the VOFM was a (1) "Facilitator for Sensation," (2) a "Physical Tool," and that there was (3) "No Program Needed" to use the VOFM in voice therapy. There was a statistically significant improvement in cepstral peak prominence (p = 0.0329) and cepstral spectral index of dysphonia (p = 0.0164) in sustained vowels.

DISCUSSION

This pilot study represents the first investigation into clinician and patient perceptions of using a VOFM. Reported measures via patient perception, as well as clinician perceptions, and some acoustic and aerodynamic measures showed that participants got better with VOFM voice therapy. Last, in general, both clinicians and patients liked utilizing a VOFM in voice therapy.

Comparative analysis of high-speed videolaryngoscopy images and sound data simultaneously acquired from rigid and flexible laryngoscope: a pilot study

High-Speed Videoendoscopy (HSV) is becoming a robust tool for the assessment of vocal fold vibration in laboratory investigation and clinical practice. We describe the first successful application of flexible High Speed Videoendoscopy with innovative laser light source conducted in clinical settings. The acquired image and simultaneously recorded audio data are compared to the results obtained by means of a rigid endoscope. We demonstrated that the HSV recordings with fiber-optic laryngoscope have enabled obtaining consistently bright, color images suitable for parametrization of vocal fold oscillation similarly as in the case of the HSV data obtained from a rigid laryngoscope. The comparison of period and amplitude perturbation parameters calculated on the basis of image and audio data acquired from flexible and rigid HSV recording objectively confirm that flexible High-Speed Videoendoscopy is a more suitable method for examination of natural phonation. The HSV-based measures generated from this kymographic analysis are arguably a superior representation of the vocal fold vibrations than the acoustic analysis because their quantification is independent of the vocal tract influences. This experimental study has several implications for further research in the field of HSV application in clinical assessment of glottal pathologies nature and its effect on vocal folds vibrations.

The Impact of Languages and Cultural Backgrounds on Voice Quality Analyses

OBJECTIVE

The aim of this study was to verify the influence of different cultural backgrounds and languages on the perception of voice quality. Another aim was to evaluate the correlation between clinical auditory-perceptual judgments with acoustic measurements, such as the acoustic voice quality index (AVQI) and the acoustic breathiness index (ABI), i.e., their effect on the concurrent validity.

METHODS

Brazilian and European participants rated 2 culturally and linguistically different datasets (i.e., 150 Brazilian Portuguese and 218 German voice sample sets), with each dataset containing concatenated voice samples of continuous speech and sustained phonation. The raters evaluated the vocal quality in terms of the overall voice quality and breathiness. Intra- and interrater reliabilities were also tested. The psychometric qualities of the AVQI and the ABI (concurrent validity and diagnostic accuracy) were analyzed, considering the perceptual ratings of Brazilian and European participants for each dataset.

RESULTS

Rater reliability decreased for nonnative participants when evaluating the nonnative dataset. Brazilian raters perceived the German voices as more severe, whereas German raters considered the overall voice quality of Brazilian voices as less severe than native raters. The concurrent validity of the AVQI and the ABI, i.e., the agreement with the auditory-perceptual evaluations, was high irrespectively of the group of participants. The diagnostic accuracy, which refers to the ability to identify a deviated voice, was higher, considering the perceptual evaluations of native listeners.

CONCLUSIONS

Brazilian raters classified voice quality as more deviated, and the Brazilian voice samples were measured to be less severe (a possible language characteristic). Further studies are necessary to verify whether there was a task or sample consequence or if adjustments to the AVQI and ABI equations are required for Brazilian Portuguese.

Do Professionals Who Use the Voice in a Journalistic Context Benefit from Humming as a Semi-occluded Vocal Tract Exercise?

INTRODUCTION

Many vocal enhancement and rehabilitation programs for voice professionals define vocal exercises without analyzing their effects on that specific population in which they will be applied, in the established dose and often without considering the presence and absence of vocal alteration. Journalists have sought the voice clinic due to new professional vocal demands and a vocal program is being elaborated.

OBJECTIVE

To determine the immediate effect of humming in professionals with and without voice disorders who work under high vocal demand in a journalistic context.

METHOD

Thirty-six individuals who completed the Dysphonia Risk Screening Protocol and underwent voice recording participated in the study. Three speech therapists defined the presence and/or absence of vocal changes by consensus. Subsequently, five repetitions of humming were proposed; the exercises lasted five seconds each and were separated by five seconds of complete silence, and recordings were made before and after the exercise (vowel and phrase). For the pre and post comparison between the groups with and without vocal changes, acoustic measurements and spectrogram, including the classification of the signal type, were performed.

RESULTS

The sample had a similar distribution of men and women and a mean age of 39.9 years. Most of the professionals were journalists or reporters. The risk of dysphonia was high for half of the sample, and the presence of vocal changes, predominantly mild ones, was identified in 56%. After the exercise, a decrease in noise at low frequencies and an improvement in the series of harmonics and the signal type were observed in both groups; a decrease in irregularity was observed only in the participants without vocal changes.

CONCLUSION

The proposed humming exercise had an immediate positive effect on the voice of professionals working in a journalistic context, and the changes were particularly evident in aspects of the voice that were initially altered.

Nasal Resistance (NR) Technique: A Novel Approach to Improve Glottal Adduction

OBJECTIVE

Several techniques have been practiced in the field of voice therapy to balance glottal pressures and improve glottal adduction. As such, Semioccluded Vocal Tract Exercises using narrow diameter straws have shown promise as a technique to increase glottal contact as reflected by Closed Quotients (CQ) measured from electroglottograph (EGG). This study explored the effect of nasal resistance (NR) technique, a manually induced NR approach, on glottal adduction in phononormal subjects as a possible new therapeutic technique to assist in glottal closure.

SUBJECTS

Thirty-four vocally healthy adult females qualified for this study. All subjects were reportedly and perceptually normal.

METHODS

Subjects were instructed to perform tasks including (a) steady modal phonation, (b) straw phonation, (c) humming, and (d) NR technique in a random order. EGG measures included calculation of the CQ and jitter during the mid-section of each stimuli for a minimum of 10 EGG cycles. One-way repeated measures ANOVAs and Bonferroni post-hoc comparisons were calculated to determine differences between each phonatory task for the outcome measures of CQ and jitter.

RESULTS

Analyses revealed that the mean CQ was significantly different in all the tasks performed with humming (33.99%) at the lowest and NR technique at highest (43.88%). Though the CQ of straw phonation (40.53%) was higher than modal steady phonation (36.65%), jitter was found to be significantly lower for NR technique (0.23%). Jitter during straw phonation (0.43%) did not differ significantly from modal phonation (0.44%).

CONCLUSION

These results provide preliminary evidence that NR technique can increase CQ with lower levels of jitter compared to straw phonation using a narrow diameter of 2 mm. Future studies should expand enrollment to men, larger age ranges, and patients with hypofunctional symptoms (eg, Parkinson disease) to evaluate the potential benefits of NR as a therapeutic technique.

Influence of Analyzed Sequence Length on Parameters in Laryngeal High-Speed Videoendoscopy

Laryngeal high-speed videoendoscopy (HSV) allows objective quantification of vocal fold vibratory characteristics. However, it is unknown how the analyzed sequence length affects some of the computed parameters. To examine if varying sequence lengths influence parameter calculation, 20 HSV recordings of healthy females during sustained phonation were investigated. The clinical prevalent Photron Fastcam MC2 camera with a frame rate of 4000 fps and a spatial resolution of 512 × 256 pixels was used to collect HSV data. The glottal area waveform (GAW), describing the increase and decrease of the area between the vocal folds during phonation, was extracted. Based on the GAW, 16 perturbation parameters were computed for sequences of 5, 10, 20, 50 and 100 consecutive cycles. Statistical analysis was performed using SPSS Statistics, version 21. Only three parameters (18.8%) were statistically significantly influenced by changing sequence lengths. Of these parameters, one changed until 10 cycles were reached, one until 20 cycles were reached and one, namely Amplitude Variability Index (AVI), changed between almost all groups of different sequence lengths. Moreover, visually observable, but not statistically significant, changes within parameters were observed. These changes were often most prominent between shorter sequence lengths. Hence, we suggest using a minimum sequence length of at least 20 cycles and discarding the parameter AVI.

Treatment Effectiveness of Novafon Local Vibration Voice Therapy for Dysphonia Treatment

BACKGROUND

The objective of this study was to explore the effectiveness of the five-week Novafon local vibration voice therapy (NLVVT) program with and without Novafon local vibration for dysphonia treatment.

METHODS

Twenty-two voice-disordered subjects were divided into two groups. The intervention group (IG) performed the NLVVT program and the control group (CG) had the same voice exercises of this program without local vibration.

RESULTS

After NLVVT, the IG showed significantly high results in all parameters of acoustics, multiparametric indices, and self-evaluation (all P values < 0.01). The CG revealed mostly much significantly lower results (P values < 0.05) or nonsignificant results for these parameters after the treatment. The intergroup comparison under consideration before and after NLVVT showed a large and significant treatment effect in voice quality (ie, narrowband spectrograms, and Acoustic Voice Quality Index), in which the IG had better treatment results. The aerodynamic measurement showed no significant changes for both groups after NLVVT (P value > 0.05).

CONCLUSION

After the NLVVT program both groups showed significant improvements of various voice measurements, in which the IG revealed better treatment results than the CG. However, next to voice exercises an extra benefit for local vibration with the Novafon appliance was assessed in voice quality.

Preliminary study of Novafon local vibration voice therapy for dysphonia treatment

Background: The objective of this study was to explore the effectiveness of a five-week Novafon local vibration voice therapy (NLVVT) program for dysphonia treatment.Methods: Eleven dysphonic subjects participated in this specific program.Results: Treatment effects were assessed during (i.e. weekly) and after NLVVT. Large and significant treatment effects were revealed in acoustics (i.e. spectrography), and multiparametric indices (i.e. Acoustic Voice Quality Index (AVQI), and Dysphonia Severity Index (DSI)) during and after NLVVT (all p values < .01). Additionally, self-evaluation (i.e. Voice Handicap Index (VHI)) showed a significant improvement after NLVVT (p < .01). Gender independent voice range profile parameters (i.e. acoustics) only showed significant effects after treatment (p ≤ .01), but not during the treatment. Finally, aerodynamic measurement (i.e. phonation quotient) showed low treatment effects after NLVVT, which were not significant (p > .05).Conclusions: The preliminary results showed that NLVVT might be successful in voice treatment. Large treatment effects might be expected in AVQI, DSI, spectrography and VHI after using NLVVT. Other voice characteristics showed smaller treatment effects (i.e. voice range profile parameters) or no meaningful treatment effects (i.e. phonation quotient).

Investigation of Flexible High-Speed Video Nasolaryngoscopy

OBJECTIVE

High-speed videolaryngoscopy is widely used in voice practices as a complement to videostroboscopy, especially when it is desired to visualize asymmetric and nonperiodic vocal fold vibration or voice onset and offset. Because of the requirement for greater illumination at higher frame rates, the high-speed exam is usually performed with a rigid transoral laryngoscope. Although it is possible to obtain color high-speed video images with a flexible fiberoptic nasoendoscope, the results are often disappointing because of the inability to provide adequate lighting inside the larynx. This paper will present the results of a systematic exploration of tools and techniques to optimize the image brightness of flexible color high-speed videolaryngoscopy exams using the KayPENTAX Model 9710 Color High-Speed Video (CHSV) System.

METHODS

The KayPENTAX CHSV System was used with three PENTAX flexible fiberoptic nasolaryngoscopes and a new supplemental light fiber bundle to perform high-speed examinations of healthy vocal folds. Variables of the investigation included camera frame rate, camera sensitivity (color head versus black-and-white head), optics (camera lens focal length), light coupling, nasoendoscope outer diameter, and endoscopy technique (visually perceived distance of the distal tip of scope from the glottal plane).

RESULTS AND CONCLUSIONS

The manipulation of camera gain, the proper selection of lens coupler focal length, and the adjustment of scope distal tip distance from the glottal plane were found to be most effective for optimizing image brightness, whereas the supplemental light fiber bundle provided minimal benefits. Other factors considered include patient comfort, practicality, and ease of use by the clinician.

Measurement of the Maximum Frequency of Electroglottographic Fluctuations in the Expiration Phase of Volitional Cough as a Functional Test for Cough Efficiency

The hypotheses of the present study were that the maximum frequency of fluctuation of electroglottographic (EGG) signals in the expiration phase of volitional cough (VC) reflects the cough efficiency and that this EGG parameter is affected by impaired laryngeal closure, expiratory effort strength, and gender. For 20 normal healthy adults and 20 patients diagnosed with unilateral vocal fold paralysis (UVFP), each participant was fitted with EGG electrodes on the neck, had a transnasal laryngo-fiberscope inserted, and was asked to perform weak/strong VC tasks while EGG signals and a high-speed digital image of the larynx were recorded. The maximum frequency was calculated in the EGG fluctuation region coinciding with vigorous vocal fold vibration in the laryngeal HSDIs. In addition, each participant underwent spirometry for measurement of three aerodynamic parameters, including peak expiratory air flow (PEAF), during weak/strong VC tasks. Significant differences were found for both maximum EGG frequency and PEAF between the healthy and UVFP groups and between the weak and strong VC tasks. Among the three cough aerodynamic parameters, PEAF showed the highest positive correlation with the maximum EGG frequency. The correlation coefficients between the maximum EGG frequency and PEAF recorded simultaneously were 0.574 for the whole group, and 0.782/0.717/0.823/0.688 for the male/female/male-healthy/male-UVFP subgroups, respectively. Consequently, the maximum EGG frequency measured in the expiration phase of VC was shown to reflect the velocity of expiratory airflow to some extent and was suggested to be affected by vocal fold physical properties, glottal closure condition, and the expiratory function.