Role of the soft palate in laryngeal functions and selected voice qualities. Simultaneous velolaryngeal videoendoscopy

Measurement of Pharyngeal Air Pressure During Phonation Using High-Resolution Manometry

Purpose The study of air pressure in the vocal tract is essential to understanding vocal function. Changes in vocal tract shape during different phonatory gestures are hypothesized to produce nonuniform air pressure across lower vocal tract locations. Current methods of air pressure measurement, however, are limited to a single location in the anterior oral cavity. The purposes of this study were (a) to assess the feasibility of a novel method of simultaneously measuring phonatory air pressure at multiple locations across the lower vocal tract using high-resolution pharyngeal manometry (HRM) and (b) to compare pressure across locations and among phonatory tasks. Method Two subjects underwent HRM while performing phonatory tasks. A catheter was passed transnasally and air pressure was measured simultaneously at five locations between the velopharyngeal port and the upper esophageal sphincter. Descriptive statistics were calculated for each location by task, and for each task averaged across locations. Results HRM was well tolerated, and air pressures from multiple locations in the lower vocal tract were able to be obtained simultaneously. During vocal tract semi-occlusion tasks, air pressures differed by location. Pressures averaged across locations demonstrated a pattern of increasing pressure with increasing semi-occlusion. Conclusions HRM is feasible for measuring air pressure simultaneously at multiple locations in the lower vocal tract during phonation with high spatial and temporal resolution, providing rich data to augment understanding of vocal function. The high spatial and temporal resolution yielded by this new method, paired with preliminary evidence that pressures change by location as a function of phonatory task, may be useful in future assays exploring differences in lower vocal tract air pressures between normal and disordered populations.

A Nonrandomized Trial for Student Teachers of an In-Person and Telepractice Global Voice Prevention and Therapy Model With Estill Voice Training Assessed by the VoiceEvalU8 App

Purpose This study investigated the effects of the in-person and telepractice Global Voice Prevention and Therapy Model (GVPTM) treatment conditions and a control condition with vocally healthy student teachers. Method In this single-blinded, nonrandomized trial, 82 participants completed all aspects of the study. Estill Voice Training was used as the stimulability component of the GVPTM to train multiple new voices meeting all the vocal needs of the student teachers. Outcomes were assessed using acoustic, perceptual, and aerodynamic measures captured by the VoiceEvalU8 app at pre and post in fall and during student teaching in spring. Results Significant improvements were achieved for several acoustic and perceptual measures in the treatment conditions, but not in the control condition. The in-person and telepractice conditions produced similar results. The all-voiced phrase and connected speech were more successful in demonstrating voice change for some of the perturbation measures as compared to sustained /a/. Conclusions The treatment conditions were successful in improving the participants' voices for fundamental frequency and some acoustic perturbation measures while maintaining the improvements during student teaching. In addition, the treatment conditions were successful in decreasing the negative impact of voice-related quality of life and vocal fatigue during student teaching. Future research should address the effectiveness of the various components of the GVPTM, the application of the GVPTM with patients with voice disorders, the relevance of defining auditory-perceptual terms by the anatomy and physiology of the voice production system (i.e., Estill Voice Training), and the continued use of the VoiceEvalU8 app for clinical voice investigations. Supplemental Material https://doi.org/10.23641/asha.13626824.

Functional Voice Assessment and Therapy Methods Supported by Telepractice, VoiceEvalU8, and Estill Voice Training

Functional assessment and therapy methods are necessary for a client-centered approach that addresses the client's vocal needs across all environments. The purpose of this article is to present the approach with the intent to encourage discussion and implementation among educators, clinicians, researchers, and students. The functional approach is defined and its importance is described within the context of the World Health Organization's International Classification of Functioning, Disability, and Health with support provided by synchronous and asynchronous telepractice, the VoiceEvalU8 app, server, and web portal, and a framework that defines voice qualities (e.g., resonance, twang, loud, and others) by the anatomy and physiology of the voice production system (i.e., Estill Figures for Voice). Case scenarios are presented to highlight application of the functional voice approach.

Assessment of Tongue Position and Laryngeal Height in Two Professional Voice Populations

Purpose To advance our current knowledge of singer physiology by using ultrasonography in combination with acoustic measures to compare physiological differences between musical theater (MT) and opera (OP) singers under controlled phonation conditions. Primary objectives addressed in this study were (a) to determine if differences in hyolaryngeal and vocal fold contact dynamics occur between two professional voice populations (MT and OP) during singing tasks and (b) to determine if differences occur between MT and OP singers in oral configuration and associated acoustic resonance during singing tasks. Method Twenty-one singers (10 MT and 11 OP) were included. All participants were currently enrolled in a music program. Experimental procedures consisted of sustained phonation on the vowels /i/ and /ɑ/ during both a low-pitch task and a high-pitch task. Measures of hyolaryngeal elevation, tongue height, and tongue advancement were assessed using ultrasonography. Vocal fold contact dynamics were measured using electroglottography. Simultaneous acoustic recordings were obtained during all ultrasonography procedures for analysis of the first two formant frequencies. Results Significant oral configuration differences, reflected by measures of tongue height and tongue advancement, were seen between groups. Measures of acoustic resonance also showed significant differences between groups during specific tasks. Both singer groups significantly raised their hyoid position when singing high-pitched vowels, but hyoid elevation was not statistically different between groups. Likewise, vocal fold contact dynamics did not significantly differentiate the two singer groups. Conclusions These findings suggest that, under controlled phonation conditions, MT singers alter their oral configuration and achieve differing resultant formants as compared with OP singers. Because singers are at a high risk of developing a voice disorder, understanding how these two groups of singers adjust their vocal tract configuration during their specific singing genre may help to identify risky vocal behavior and provide a basis for prevention of voice disorders.

Spectrum Effects of a Velopharyngeal Opening in Singing

The question whether or not a velopharyngeal opening is advantageous in singing has been discussed for a very long time among teachers of singing. The present investigation analyzes the acoustic consequences of a large, a narrow, and a nonexistent velopharyngeal opening (VPO). A divided flow mask (nasal and oral) connected to flow transducers recorded the nasal and oral DC flows in four female and four male classically trained singers while they sang vowel sequences at different pitches under these three experimental conditions. Acoustic effects were analyzed in three long-term average spectra parameters: (i) the sound level at the fundamental frequency, (ii) the level of the highest peak below 1 kHz, and (iii) the level of the highest peak in the 2-4 kHz region. For a narrow VPO, an increase in the level of the highest peak in the 2-4 kHz region was observed. As this peak is an essential voice component in the classical singing tradition, a narrow VPO seems beneficial in this type of singing.

Singing Teachers and Voice Science - An Evaluation of Voice Teaching in Australian Tertiary Institutions

The article documents a qualitative research project which evaluated the voice pedagogy of singing teachers in Australian tertiary institutions, particularly in relation to their use of recent voice science findings. The literature of voice science relevant to singing was surveyed and extended interviews were conducted with 50 singing teachers. Using the methodology of grounded theory, the interview data were analysed in categories identified as common to both voice science and practitioner understandings. It was clear from the results of the study that most singing pedagogy in Australian tertiary institutions is practised with incomplete knowledge of vocal physiology and acoustics, and/or misinformation with respect to some aspects of vocal functioning.

Since the results of physiological, acoustic and other scientific research conducted in recent decades constitute a valuable addition to the body of knowledge traditionally used in singing pedagogy, the study has implications for the professional education of singing teachers for the 21st century.

Clinical investigation of the Global Voice Therapy Model

The purpose of this study was to investigate the effect of the Global Voice Therapy Model (GVTM) on acoustic, aerodynamic, and perceptual voice measures of four adults seeking voice therapy for a voice disorder. A speech-language pathologist facilitated speaking voice therapy with the four participants using the GVTM. Participants completed acoustic, aerodynamic, and perceptual voice measures at pre- and post-therapy time points. Differences were seen in the voice measures from pre- to post-therapy. The GVTM was successful in facilitating an improvement in the acoustic, aerodynamic, and perceptual measures of the participants.

The perception of two vocal qualities in a synthesized vocal utterance: ring and pressed voice

Two vocal qualities, ring quality and pressed quality, were analyzed perceptually. Listeners were asked to rate (on a scale from 0 to 10) the "amount of ring" in one listening and the "amount of pressedness" in another listening. The stimulus was the synthesized utterance /ya-ya-ya-ya-ya/. In the continuum representation of ring, the skewing quotient and the cross section of the epilaryngeal tube area were systematically varied, independently and by a covariation rule. In the continuum representation of pressed, the flow amplitude and open quotient were similarly varied. Results indicated that the crossover point between ring and no ring occurred with an epilaryngeal area of around 1.0 cm2, and the crossover point between pressed and not pressed quality occurred at an open quotient of about 0.4. Fundamental frequency also had an effect on the perceptions, with a higher fundamental frequency receiving higher ratings of ring and pressed for otherwise the same parameters. Listeners demonstrated highly variable perceptions in both continua with poor intersubject, intrasubject, and intergroup reliability.

Role of flexible laryngoscopy in evaluating aspiration

Flexible fiberoptic laryngoscopy is used to evaluate dysphagia, but its clinical utility has not been compared to that of the videofluorographic swallowing study (VFSS). This study correlates parameters of both procedures and identifies laryngoscopic predictors of aspiration in 105 patients. Presence of aspiration, pharyngeal residue, laryngeal sensation, vocal cord mobility, and glottic closure during flexible laryngoscopy (FL), and gag reflex were correlated with aspiration during the VFSS. An algorithm for laryngoscopically detecting aspiration was synthesized. Aspiration (p = .004) and pharyngeal residue (p < .00001) were highly correlated between the two studies. Aspiration during the VFSS was correlated with pharyngeal residue (p < .00001) and laryngeal sensation (p = .027) during FL, but not glottic closure (p = .169) nor vocal cord mobility (p = .056). Patients with a normal gag reflex and without aspiration or pharyngeal residue during FL had a 2.94% risk of aspiration during the VFSS. Flexible laryngoscopy can be used as a relatively safe, portable screening test for aspiration, but cannot always replace the VFSS to identify the presence or cause of aspiration.

The Use of Video in ENT Endoscopy: Its Value in Teaching

Videography is the most practical and effective method of documenting and teaching ENT endoscopy. Videography allows: (1) documentation of anatomy, physiology and pathology of deep structures of the ear, nose and throat; (2) teaching of delicate surgical procedures such as functional endoscopic sinus surgery (FESS), laryngeal surgery, and other endoscopic procedures; (3) instantaneous production of high quality hard copies of video images for teaching and patient records; (4) instant replay and repeated viewing by a slow motion or frame-by-frame analysis; (5) simultaneous viewing by a small or large audience; and (6) image digitalization for storage in the computer for later analysis. The author describes the value of videography in ENT endoscopy, namely video-otoscopy, video rhinoscopy and video-laryngoscopy. The use of video in endoscopy will continue to play a vital role in Continuing Medical Education (CME).

Videoendoscopic diagnosis and correction of velopharyngeal stress incompetence in a bassoonist

Musicians who play woodwind or brass instruments must generate extremely high intraoral pressures to achieve normal tone and volume in their music. Intraoral pressures of 130 mm Hg can be reached, while normal speech rarely exceeds 6 mm Hg. The inability to maintain an effective seal between the soft palate and the pharyngeal wall can manifest as difficulty in holding high notes or in playing sustained music compositions, or noise production from turbulent nasal cavity emissions. Throughout the literature, there are few reports of these entities. We will present the case of a 31-year-old concert bassoonist who complained of "noise from her head" only when she played the bassoon. This resulted in numerous failed auditions and threatened her professional career. The diagnosis of velopharyngeal stress incompetence, as well as the Teflon injection augmentation procedure, was done under local anesthesia with the subject playing the bassoon. The use of videoendoscopic techniques allowed accurate, reproducible assessment of the defect and the operative procedure, and assisted in postoperative evaluation.

Endoscopic and videofluoroscopic evaluations of swallowing and aspiration

A new procedure for evaluating oropharyngeal dysphagia utilizing fiberoptic laryngoscopy was compared to the videofluoroscopy procedure. Twenty-one subjects were given both examinations within a 48-hour period. Results of the fiberoptic endoscopic evaluation of swallowing (FEES) and videofluoroscopy examinations were compared for presence or absence of abnormal events. Good agreement was found, especially for the finding of aspiration (90% agreement). The FEES was then measured against the videofluoroscopy study for sensitivity, specificity, positive predictive value, and negative predictive value. Sensitivity was 0.88 or greater for three of the four parameters measured. Specificity was lower overall, but was still 0.92 for detection of aspiration. It was concluded that the FEES is a valid and valuable tool for evaluating oropharyngeal dysphagia. Some specific patients and conditions that lend themselves to this procedure are discussed.

Supraglottic contributions to pitch raising. Videoendoscopic study with spectroanalysis

Several questions pertaining to pitch raising recur frequently. Does the larynx rise with the production of higher frequencies? What happens to the pharyngeal walls between the soft palate and the larynx when the fundamental frequency is raised? How does the soft palate participate in pitch raising? To answer these questions, the present study was undertaken with the recently described simultaneous velolaryngeal endoscopy technique. Nine professional singers were asked to find the limits of their vocal range in any of six voice qualities: speech, falsetto, cry/sob, twang, belting, and opera. Simultaneous activities of the larynx, the pharyngeal walls, and the soft palate were submitted to videoendoscopy with synchronous voice recording and studied with spectroanalysis of discrete segments of the total phonation range. Our dual endoscopic study showed that 1) the larynx rose in all subjects with the production of higher frequencies, 2) with the highest fundamental frequency, the lateral pharyngeal walls significantly contracted toward the midline in an "upside-down V shape," creating a very narrow pharyngeal tube, and 3) the soft palate lifted and the velopharyngeal port narrowed considerably with higher frequencies.