Kristine Tanner, Ph. D., Department of Communication Disorders, Ray M. Merrill, Ph.D., Department of Health Science, Shawn Nissen, Ph.D., Department of Communication Disorders, and Scott Thomson, Ph.D., Department of Mechanical Engineering

1. Summary of Academic Objectives Met

The purpose of this multidisciplinary Mentoring Environment Grant was to support students as they mastered novel objective methodologies for quantifying voice function. Speech pathology graduates who are skilled in novel technologies to document voice function are significantly more marketable for competitive medical speech-­language pathology employment. The context for education in these novel measures included a series of studies involving the effects of voice dryness and new hydration treatments to improve voice function.

Each student involved in this MEG project obtained novel objective methodologies to quantify voice function. Students were actively engaged in acoustic and physiologic voice measurement techniques including in vivo and ex vivo methodologies, which resulted in competitive skill sets for future medical speech-­ language pathology placements. Several of these students have already been placed in competitive employment environments, and two have begun doctoral work in prestigious Ph.D. programs. Additionally, students have served as authors on numerous national conference presentations and journal publications;; future submissions are also pending. In summary, the present MEG project successfully exceeded all objectives.

2. Evaluation of Mentoring Environment

MEG funding has been matched by the David O. McKay School of Education and Department of Communication and Disorders in the purchase of new high-­speed endoscopy equipment for the benefit of speech-­language pathology training and research. Additionally, the college and department have appropriated space in the John Taylor Building for the support of this mentoring and research. The resulting environment was combined with multi-­level student mentoring in an interactive and supportive research atmosphere. Students were challenged to accomplish the academic goals set forth in the MEG proposal. At the same time, the supportive environment permitted maximum creativity and learning. Students debriefed after the research experience indicated that the environment was highly productive and greatly enhanced the learning process.

3. Academic Deliverables

Students who have participated in the MEG academic deliverables:

BYU Undergraduate Students

• Katharina Burton (Communication Disorders)
• Mark Berardi (Physics & Astronomy)
• Katharina Burton (Communication Disorders)
• Shani Nance (Communication Disorders)
• Aaron Stowell (Communication Disorders)
• Rachelle Winckel (Communication Disorders)

BYU Graduate Students

• Emily Berardi (Communication Disorders)
• Robert Fujiki (Communication Disorders)
• Mallory Hansen (Communication Disorders)
• Victoria Lovett (Communication Disorders)
• Lisa Mattei (Communication Disorders)
• Alison Miner (Communication Disorders)
• Maya Nunez (Communication Disorders)
• Whitney Robb (Communication Disorders)

BYU Doctoral Students

• Kim Stevens (Mechanical Engineering)

Peer-­Reviewed Journal Articles:

• Tanner, K., Nissen, S. L., Merrill, R. M., Miner, A. (graduate student), Channell, R. W., Miller, K. L., Elstad, M. R., Kendall, K. A., & Roy, N. (2015). Nebulized isotonic saline improves voice production in Sjögren’s Syndrome. The Laryngoscope, 125, 2333-­2340. [PMID: 25781583]
• Tanner, K., Fujiki, R. B. (graduate student), Dromey, C., Merrill, R. M., Robb, W. (graduate student), Kendall, K. A., Hopkin, J. A., Channell, R. W., & Sivasankar, M. P. (in press). Laryngeal desiccation challenge and nebulized isotonic saline in healthy male singers and nonsingers: Effects on acoustic, aerodynamic, and self-­perceived effort and dryness measures. Journal of Voice.

Peer-­Reviewed Conference Presentations:

• Stevens, K. A. (doctoral student), Tanner, K., & Thomson, S. L. A Non-­traditional view of the vocal folds: Transcutaneous illumination revisited. Poster presented at the 9th International Conference on Voice Physiology and Biomechanics, Salt Lake City, Utah, April 11, 2014.
• Fujiki, R. B. (graduate student), Robb, W. J. (graduate student), Tanner, K., Dromey, C., Kendall, K. A., Hopkin, J. A., Channell, R. W., & Sivasankar, M. P. The effects of laryngeal desiccation and nebulized isotonic saline in male singers and nonsingers. Poster presented at the American Speech-­Language-­Hearing Association Convention, Orlando, Florida, November 20, 2014.
• Corbin-­Lewis, K., Christensen, K. (graduate student), Kendall, K. A., Tanner, K., & Fujiki, R. B. (graduate student). Quantitative videofluoroscopic swallow study (VFSS) measures: Student training outcomes. Poster presented at the American Speech-­ Language-­Hearing Association Convention, Orlando, Florida, November 20, 2014.
• Miner, A. (graduate student), Tanner, K., Nissen, S. L., Merrill, R. M., Miller, K. L., Lovett, V. (graduate student), Channell, R. W., Elstad, M., Kendall, K. A., & Roy, N. Quantifying the long-­term effects of nebulized saline on voice production in Sjögren’s Syndrome. Poster presented at the American Speech-­Language-­Hearing Association Convention, Orlando, Florida, November 21, 2014. *Meritorious Poster Award
• Tanner, K., Nissen, S. L., Merrill, R. M., Miner, A. (graduate student), Channell, R. W., Miller, K. L., Elstad, M. R., Kendall, K. A., & Roy, N. Nebulized isotonic saline improves voice production in Sjögren’s Syndrome. Poster presented at the American Laryngological Association Spring Meeting at COSM, Boston, Massachusetts, April 23, 2015.
• Tanner, K., Nissen, S.L., Channell, R.W., Berardi, M. (undergraduate student), Berardi, E. (graduate student), Lovett, V. (graduate student), & Stowell, A (undergraduate student). Quantifying changes in vocal fold hydration using relative fundamental frequency (RFF) analysis during connected speech. American Speech-­Language-­ Hearing Association, Denver, Colorado, November 14, 2015.

Upcoming Presentations and Journal Submissions:

• Tanner, K., Smith, M. E., Dromey, C., Berardi, M. L. (undergraduate student), Mattei, L., M. (graduate student), Wisco, J. J., Hunter, E., J., & Thomson, S. L. Effects of subglottic stenosis and cricotracheal resection on voice production in adult females. Upcoming presentation at the Combined Otolaryngology Spring Meetings (May 2016) and submission to The Laryngoscope.
• Tanner, K., Berardi, M. L., Dromey, C., Stevens, K., Hansen, M., Nunez, M., Titze, I. R., Sivasankar, M. P. An ex vivo model for the prevention of vocal fold dehydration using prophylactic aerosolized saline. Upcoming presentation at the Voice Foundation Annual Symposium and submission to the Journal of Voice.
• Tanner, K., Berardi, M. L., Nissen, S. L., Lovett, V. Quantifying changes in vocal fold hydration using relative fundamental frequency (RFF) analysis during connected speech. Journal of Speech, Language, & Hearing Research.

4. Description of Results

4.1 Acoustic Analysis of Voice Production

Relative fundamental frequency (RFF) analysis involves the comparison of periods between glottal pulses during vowels immediately prior to and following a voiceless consonant. The durations of the periods prior to the voiceless consonant (i.e., voicing offset) and following the voiceless consonant (i.e., voicing onset) are compared to periods during the vowel steady state, operationally defined as the 10^th cycle from the voiceless consonant. Unlike many acoustic measures of voice production, RFF analysis is also possible with connected speech samples. RFF characteristics seem to differ between children and adults (Watson, 1998), men and women (Robb & Smith, 2002), and between those with and without certain disease processes such as Parkinson’s Disease (Goberman & Blomgren, 2008). Recent research indicates that RFF differs predictably between individuals with normal versus disordered voices (Lien & Stepp, 2013;; Stepp, Hillman, & Heaton, 2010). Additionally, RFF has been shown to reliably track voice change following improvement with treatment (Stepp, Merchant, Heaton, & Hillman, 2011). Therefore, RFF shows promise as a measure of voice disorder severity and voice change with treatment.

It has been hypothesized that several voice production factors—including vocal fold abduction/adduction, transglottal airflow, and vocal fold tension—might have particular influence on offset and onset associated with RFF (Lofqvist, Koenig, & McGowan, 1995). For example, it is possible that individuals with Parkinson’s Disease might control voicing offset predominantly using vocal fold abduction versus manipulating vocal fold tension (Goberman & Blomgren, 2008). Similarly, functional changes in vocal fold tension might explain corresponding changes in RFF in individuals with muscle tension dysphonia and vocal nodules (Stepp et al., 2010;; 2011). Due to its sensitivity to functional voice changes, RFF might be a useful measure to identify individuals who are at-­risk for developing voice disorders (Stepp et al., 2011). However, additional research is needed regarding the use of RFF to quantify voice changes related to various causative factors and across different patient populations.

Preliminary analyses indicated that RFF values were approximately .40 semitones greater during the hydration treatment versus non-­treatment conditions. These increases were statistically significant for voicing onset based on Freidman tests for related samples (p < .05). Intrajudge reliability was calculated for 15% of repeated analyses. A Spearman correlation of .85 (p < .001) and an average absolute difference of .26 semitones demonstrated acceptable levels of measurement reliability. Analysis of the results indicated that baseline RFF values were in the voice-­ disordered range based on recent studies involving speakers with typical versus disordered voices (Lien et al., 2013;; Stepp et al., 2010;; 2011). Additionally, average RFF values improved following nebulized saline treatment during morning and evening offset cycle 10 and morning onset cycle 1 tokens;; these improvements were statistically significant at the .05 alpha level for the morning onset cycle 1 tokens. In general, these results indicate that RFF may be a sensitive measure for voice severity in the Primary Sjogren’s Syndrome population;; RFF might also be sensitive to functional changes in voice production with vocal fold hydration treatment.

4.2.1 Physiologic Analysis of Voice Production

Summary: Objectives. This study examined the effects of a laryngeal desiccation challenge and nebulized isotonic saline on voice production in young, healthy male singers and nonsingers.

Study Design. Prospective, double-­blind, within-­subjects experimental design.

Methods. Participants included 10 male university-­trained singers and 10 age-­ matched nonsingers (mean age = 21.8 years;; range = 18-­26 years) who underwent a 30-­minute oral breathing laryngeal desiccation challenge using medical grade dry air (<1% relative humidity) on 2 occasions in consecutive weeks. Following the challenge, participants received either 3 mL or 9 mL of nebulized isotonic saline (0.9% Na⁺Cl^–­);; order of administration was counterbalanced. Phonation threshold pressure (PTP), the cepstral spectral index of dysphoniaTM (CSID) for sustained vowels and connected speech, and self-­perceived vocal effort, mouth dryness, and throat dryness were measured at each recording (baseline, post-­challenge, and at 5, 35, and 65 minutes post-­treatment).

Results. Self-­perceived effort and dryness measures increased (worsened) after desiccation challenge and decreased (improved) after nebulized treatment (p < .05). No consistent changes were observed for PTP or CSID over time. Overall, singers demonstrated significantly lower vocal effort and CSID as compared with nonsingers. Conclusions. Young, vocally-­healthy males may not experience physiologic changes in voice production associated with laryngeal desiccation and nebulized saline treatments;; however, self-­reported increases in vocal effort which are associated with dryness symptoms might improve with nebulized treatments. Future hydration research should consider age and sex variables.

4.2.2 Physiologic Analysis of Voice Production

Objectives: Ex vivo models of vocal fold surface hydration have established important relationships between hydration state and voice function. The present study employed an ex vivo animal model to determine if prophylactic aerosolized saline could prevent the adverse effects of a laryngeal desiccation challenge on voice production.

Method: Bench-­mounted porcine larynges received incremental (1-­minute) doses of aerosolized isotonic saline (0.9% Na+Cl-­) via an ultrasonic nebulizer situated directly above the vocal folds via custom tubing. PTP was measured at 1-­minute intervals. Following 15 minutes of aerosolized saline administration, larynges received 1-­minute increments of desiccated air (<1% relative humidity). Again. PTP was measured at each 1-­minute interval until the vocal folds ceased to vibrate. These results were compared to control larynges receiving 1-­minute increments of desiccated air without prophylactic treatment. Results: Significant decreases in PTP were observed following 15 minutes of aerosolized saline compared to no treatment. Following 5 minutes of laryngeal desiccation, PTP returned to baseline values for larynges treated with aerosolized saline;; PTP from control larynges was significantly greater than baseline. Discussion: The results from this study indicate that aerosolized saline may be used to prevent the adverse effects of laryngeal desiccation on voice function. This study advances important theoretical constructs related to dehydration-­related voice disorder prevention in a more physiologically realistic mechanical model.

4.2.3 Comparison of Subjective versus Objective Measures

Objective: This study examined the effects of a topical vocal fold hydration treatment on voice production over time.

Study Design: Prospective, longitudinal, within-­subjects A (baseline), B (treatment), A (withdrawal/reversal), B (treatment) experimental design.

Methods: Eight individuals with Primary Sjögren’s Syndrome (SS)—an autoimmune disease causing laryngeal dryness—completed an 8-­week A-­B-­A-­B experiment. Participants performed twice-­daily audio recordings of connected speech and sustained vowels, and rated vocal effort, mouth dryness, and throat dryness. Two-­ week treatment phases introduced twice-­daily 9 mL doses of nebulized isotonic saline (0.9% Na⁺Cl^–­). Voice handicap and patient-­based measures of SS disease severity were collected before and after each two-­week phase. Connected speech and sustained vowels were analyzed using the Cepstral Spectral Index of Dysphonia (CSID).™ Acoustic and patient-­based ratings during each baseline and treatment phase were analyzed and compared.

Results: Baseline CSID and patient-­based ratings were in the mild-­to-­moderate range. CSID measures of voice severity improved by approximately 20% with nebulized saline treatment and worsened during treatment withdrawal. Post-­treatment CSID values fell within the normal-­to-­mild range. Similar patterns were observed in patient-­ based ratings of vocal effort and dryness. CSID values and patient-­based ratings correlated significantly (p < .05). Conclusion: Nebulized isotonic saline improves voice production based on acoustic and patient-­based ratings of voice severity. Future work should optimize topical vocal fold hydration treatment formulations, dose, and delivery methodologies for various patient populations. This study lays groundwork for future topical vocal fold hydration treatment development to manage and possibly prevent dehydration-­related voice disorders.

5. Description of Budgetary Spending

Budgetary spending followed the proposed budget in the original MEG application. Briefly, funds were primarily applied to support students during research training during experimental research. Funds were also used to support student travel to present their research at national conferences. Additionally, funds were used to purchase research materials and supplies to perform research activities.