Efficacy of Phonosurgery, Logopedic Voice Treatment and Vocal Pedagogy in Common Voice Problems of Singers

Return to Vocal Performance Following Microlaryngoscopy in Singers

INTRODUCTION

Although microlaryngoscopy has been recognized to be effective in addressing lesions in vocal performers, no detailed information regarding return to performance (RTP) following surgery exists. We describe our experience and offer proposals to establish standardized criteria for RTP among vocal performers.

METHODS

Records for adult vocalists who underwent microlaryngoscopy for benign vocal fold (VF) lesions and had a clearly documented RTP date between 2006 and 2022 were reviewed. Patient demographics, diagnoses, interventions, and postsurgical care before and after RTP were described. The need for medical and procedural interventions and rate of reinjury were used to determine the success of RTP.

RESULTS

Sixty-nine vocal performers (average age: 32.8 years, 41 [59.4%] female, 61 [88.4%] musical theater) underwent surgery for 37 (53.6%) pseudocysts, 25 (36.2%) polyps, 5 (7.2%) cysts, 1 (1.4%) varix, and 1 (1.4%) mucosal bridge. Fifty-seven (82.6%) underwent voice therapy. The average time to RTP was 65.0 ± 29.8 days. Prior to RTP, six (8.7%) experienced VF edema requiring oral steroids and one (1.4%) underwent a VF steroid injection. Within 6 months following RTP, eight (11.6%) received oral steroids for edema and three underwent procedural interventions (two steroid injections for edema/stiffness, one injection augmentation for paresis). One patient experienced pseudocyst recurrence.

CONCLUSIONS

Return to vocal performance at an average of 2 months following microlaryngoscopy for benign lesions appears overwhelmingly successful, with low rates of need for additional intervention. There is a need for validated instruments to better measure performance fitness to refine and possibly accelerate RTP.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:329-334, 2024.

Pre and Post-operative Voice Therapy Intervention for Benign Vocal Fold Lesions: A Systematic Review

Benign vocal fold lesions cause dysphonia by preventing vocal fold closure, causing irregular vibration and increasing compensatory muscle tension. Voice therapy delivered in addition to phonosurgery may improve voice and quality of life outcomes but the evidence base is lacking and what constitutes voice therapy for this population is not defined. The purpose of this systematic review is to critically evaluate the evidence for pre and post-operative voice therapy to inform the development of an evidence based intervention.

STUDY DESIGN

Systematic Review.

METHODS

Electronic databases were searched using key terms including dysphonia, phonosurgery, voice therapy and outcomes. Eligible articles were extracted and reviewed by the authors for risk of bias and for information regarding the content, timing and intensity of any pre and post-operative voice therapy intervention.

RESULTS

Of the 432 articles identified, 35 met the inclusion criteria and were included in the review. 5 were RCTs, 2 were individual cohort studies, 1 was a case control study and 26 were case series. There was considerable heterogeneity in participant characteristics. Information was frequently lacking regarding the content timing and intensity of the reported voice therapy intervention, and where present, interventions were highly variable.

CONCLUSION

Reporting in relevant literature is limited in all aspects of content, timing and intensity of intervention. Further intervention development work is required to develop a robust voice therapy treatment intervention for this population, before effectiveness work can commence.

Harnessing Machine Learning in Vocal Arts Medicine: A Random Forest Application for "Fach" Classification in Opera

Vocal arts medicine provides care and prevention strategies for professional voice disorders in performing artists. The issue of correct "Fach" determination depending on the presence of a lyric or dramatic voice structure is of crucial importance for opera singers, as chronic overuse often leads to vocal fold damage. To avoid phonomicrosurgery or prevent a premature career end, our aim is to offer singers an improved, objective fach counseling using digital sound analyses and machine learning procedures. For this purpose, a large database of 2004 sound samples from professional opera singers was compiled. Building on this dataset, we employed a classic ensemble learning method, namely the Random Forest algorithm, to construct an efficient fach classifier. This model was trained to learn from features embedded within the sound samples, subsequently enabling voice classification as either lyric or dramatic. As a result, the developed system can decide with an accuracy of about 80% in most examined voice types whether a sound sample has a lyric or dramatic character. To advance diagnostic tools and health in vocal arts medicine and singing voice pedagogy, further machine learning methods will be applied to find the best and most efficient classification method based on artificial intelligence approaches.

Postoperative Voice Surgical Outcomes in Professional Singers vs Non-Singers

OBJECTIVES

Professional singers often are described as vocal athletes, and just as professional athletes get injured, injuries to professional singers can occur during practice and performances. In other fields of medicine, research has shown that competitive sports athletes recover more quickly after orthopedic surgical procedures compared to non-athletes. The purpose of this study was to determine whether similar differences occur with voice patients by comparing voice surgical outcomes between professional singers and non-singers.

METHODS

A retrospective cohort study was conducted that included a consecutive sample of 194 adult subjects who underwent voice surgical procedures in the operating room. All surgeries were performed by the same surgeon, the senior author of this study (RTS). Data were reviewed for patients with medical records between January 1, 2010 to February 1, 2022. Subjects who reported receiving income from singing or reported studying voice at a collegiate level or higher were classified as professional singers. Subjects reporting careers in all other professions, including unpaid avocational singers or singers without formal training, were assigned to the non-singer control group. The data were analyzed using SPSS statistical software. Statistical significance was determined using independent samples t test for continuous variables and Fisher's exact test or binary logistic regression for binary outcomes.

RESULTS

There were 194 subjects included in this study (43.81% male/56.19% female). The average age was 42.60 ± 15.17. Ninety subjects were professional singers and 104 were non-singers. Revision of surgical plan was significantly different for professional singers compared to non-singers (14.44% versus 0%, P < 0.001). The rate of postoperative complications did not differ significantly between the singer and non-singer groups, even when adjusting for other factors. Professional singers presented with slightly more severe vocal fold hemorrhages on the first postoperative visit compared to non-singers (1.73 ± 0.73 versus 1.32 ± 0.65, P = 0.003), but there was no difference by the second visit. Following surgery, professional singers adhered to a longer duration of voice rest. However, both groups participated equally in voice therapy postoperatively.

CONCLUSIONS

No differences were found in operative complications between professional singers and non-singers. This study describes outcomes and considerations in patient care for professional singers. It also provides insight into potentially modifiable factors, such as voice rest, that could impact patient care postoperatively.

New objective timbre parameters for classification of voice type and fach in professional opera singers

Voice timbre is defined as sound color independent of pitch and volume, based on a broad frequency band between 2 and 4 kHz. Since there are no specific timbre parameters, previous studies have come to the very general conclusion that the center frequencies of the singer's formants are somewhat higher in the higher voice types than in the lower ones. For specification, a database was created containing 1723 sound examples of various voice types. The energy distribution in the frequency bands of the singer's formants was extracted for quantitative analysis. When the energy distribution function reached 50%, the corresponding absolute frequency in Hz was defined as Frequency of Half Energy (FHE). This new parameter quantifies the timbre of a singing voice as a concrete measure, independent of fundamental frequency, vowel color and volume. The database allows assigning FHE means ± SD as characteristic or comparative values for sopranos (3092 ± 284 Hz), tenors (2705 ± 221 Hz), baritones (2454 ± 206 Hz) and basses (2384 ± 164 Hz). In addition to vibrato, specific timbre parameters provide another valuable feature in vocal pedagogy for classification of voice type and fach according to the lyric or dramatic character of the voice.

Voice Therapy Expectations for Injured Singers

OBJECTIVES/HYPOTHESIS

Voice therapy is a mainstay treatment modality in the management of phonotrauma in singers. However, the typical duration of therapy an injured singer undergoes is unknown. The primary aims of the study were to determine (1) the number of therapy sessions preceding a decision for surgery and (2) the number of sessions and length of time to achieve improvement in singers who did not undergo surgery. Whether specific singer factors were associated with the length of therapy was also investigated.

STUDY DESIGN

Retrospective.

METHODS

Records of singers with phonotraumatic vocal fold lesions seen over a 9-year period at a tertiary care voice center were reviewed.

RESULTS

Sixty singers who underwent surgery and 183 singers who did not undergo surgery were included in the final analysis. In nearly ¾ of the surgical patients, five or fewer voice therapy sessions were completed prior to the decision for surgery. Singers who did not undergo surgery required on average 3-4 sessions before noting improvement. Over 60% of the non-surgical singers improved within 3 months and 84% were judged to be improved by 6 months. Lesion type, professional/amateur status, formal voice training, and having a current voice teacher/coach were not associated with the length of voice therapy.

CONCLUSIONS

The length of voice therapy prior to decision for surgery was limited, and so was the length of therapy leading to initial improvement in singers who did not require surgery. These findings provide a framework for voice therapy expectations and could be reassuring for this unique population.

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.

Performing Arts Medicine

Performing artists are a unique subset of athletes. With the highly repetitive nature of performance training, emphasis on proper technique, ergonomics, and preventive cross-training is vital, as many injuries are due to overuse or poor technique. There are novel medical concerns in performers, including ENT problems, mental health concerns and substance use risks. While music is central to performances, it is also a treatment modality to address cognitive, sensory, and motor dysfunctions in certain neurological conditions. Due to this wide array of issues, it is imperative to understand the specific needs and risks of performers to provide optimal medical care.

Data Collection Methods for the Voice Range Profile: A Systematic Review

Purpose To assess data collection variability in the voice range profile (VRP) across clinicians and researchers, a systematic review was conducted to evaluate the extent of variability of specific data collection points that affect the determination of frequency range and sound level and determine next steps in standardization of a VRP protocol. Method A systematic review was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis checklist. Full-text journal articles were identified through PubMed, Web of Science, Psych Info, ProQuest Dissertations and Theses Global, Google Scholar, and hand searching of journals. Results A total of 1,134 articles were retrieved from the search; of these, 463 were duplicates. Titles and abstracts of 671 articles were screened, with 202 selected for full-text review. Fifty-four articles were considered eligible for inclusion. The information extracted from these articles revealed the methodology used to derive the VRP was extremely variable across the data points selected. Additionally, there were eight common acoustic measures used for statistical analysis described in included studies that were added as a data point. Conclusions The data collection methods for the VRP varied considerably. Standardization of procedures was recommended for clinicians and researchers.

Monitoring the Outcome of Phonosurgery and Vocal Exercises with Established and New Diagnostic Tools

Instrument-assisted measuring procedures expand the options within phoniatric diagnostics by quantifying the condition of the voice. The aim of this study was to examine objective treatment-associated changes of the recently developed vocal extent measure (VEM) and the established dysphonia severity index (DSI) in relation to subjective tools, i.e., self-evaluation via voice handicap index (VHI-12) and external evaluation via auditory-perceptual assessment of hoarseness (H). The findings for H (3 raters' group assessment), VHI-12, DSI, and VEM in 152 patients of both sexes (age range 16–75 years), taken before and 3 months after phonosurgery or vocal exercises, were compared and correlated. Posttherapeutically, all of the recorded parameters improved (p < 0.001). The degree of H reduced on average by 0.5, the VHI-12 score sank by 5 points, while DSI and VEM rose by 1.5 and 19, respectively. The correlations of these changes were significant but showed gradual differences between H and VHI-12 (r = 0.3), H and DSI (r = −0.3), and H and VEM (r = −0.4). We conclude that all investigated parameters are adequate to verify therapeutic outcomes but represent different dimensions of the voice. However, changes in the degree of H as gold standard were best recognized with the new VEM.