Optimal Duration for Voice Rest After Vocal Fold Surgery: Randomized Controlled Clinical Study

Seven Days of Voice Rest Post-phonosurgery Is Not Better than 3 days: A Prospective Randomized Short-term Outcome Study

OBJECTIVE

The aim of the study is to compare the short-term effect of 7 versus 3 days of voice rest (VR) on objective vocal (acoustic) parameters following phonosurgery.

METHODS

A prospective randomized study conducted at a tertiary referral medical center. Patients with vocal fold nodules, polyps, or cysts and scheduled for phonosurgery were recruited from the Voice Clinic. They were randomized into groups of 7- or 3-day postoperative VR periods and their voices were recorded preoperatively and at 4-week postoperatively. A mixed linear model statistical analysis (MLMSA) was used to compare pre- and postoperative jitter, shimmer, harmonic-to-noise ratio, and maximum phonation time between the two groups.

RESULTS

Sixty-five patients were recruited, but only 34 fully complied with the study protocol, and their data were included in the final analysis (19 males, 20 females; mean age: 40.6 years; 17 patients in the 7-day VR group and 16 in the 3-day VR group). The groups were comparable in age, sex, and type of vocal lesion distribution. The preoperative MLMSA showed no significant group differences in the tested vocal parameters. Both groups exhibited significant (p < 0.05) and comparable improvement in all vocal parameters at postoperative week 4.

CONCLUSIONS

A VR duration of 7 days showed no greater benefit on the examined vocal parameters than the 3-day protocol 4-week postoperatively. Our results suggest that a 3-day VR regimen can be followed by patients who undergo phonosurgery without compromising the vocal results. Larger-scale and longer-duration studies are needed to confirm our findings.

LEVEL OF EVIDENCE

2 Laryngoscope, 134:4661-4666, 2024.

Is Postoperative Voice Rest Unnecessary? A Systematic Review and Meta-analysis of Voice Rest Recommendation Outcomes

BACKGROUND

Voice rest (VR) is widely recommended after microlaryngeal surgery to facilitate recovery and improve voice outcomes. Our study is the first systematic review and meta-analysis summarizing the impact of postoperative absolute voice rest (AVR) and no voice rest (NVR) instructions on voice outcomes.

METHODS

PubMed, Embase, and Cochrane Library databases were searched using "voice rest laryngeal surgery" and "postoperative voice rest" for articles published before December 2022. Risk of bias was assessed using ROBINS-I and RoB2 tools. Meta-analysis using a random effects model was performed for studies comparing Voice Handicap Index (VHI-10) outcomes between NVR and AVR. Analysis was performed in R Studio.

RESULTS

In total, 255 articles were reviewed, 24 underwent full-text screening, and nine met inclusion criteria. Four randomized control trials (RCT) and one retrospective review compared AVR durations (range: 2-10days). Four studies (two cohort, one cross-sectional, and one RCT) compared AVR to NVR. All studies had risk of bias (ROBINS-I: two moderate, two serious; RoB2: five with concerns). Comparing AVR durations, two found no difference between short and long duration, while two reported improved outcomes for the short cohort. In studies comparing AVR to NVR, all concluded no significant difference in outcomes. Pooled analysis of three studies (355 patients) comparing NVR and AVR demonstrated no significant differences in pre- and postoperative VHI-10 change (mean difference=-0.87; 95% CI, -2.51 to 0.77; P = 0.27).

CONCLUSION

Systematic review findings indicate postoperative VR may not lead to improved voice outcomes, and a meta-analysis demonstrated no difference in VHI-10 outcomes between AVR and NVR.

LEVEL OF EVIDENCE: 2

Clinical Voice Outcomes for Two Voice Rest Protocols after Phonomicrosurgery

OBJECTIVES

Voice rest is commonly recommended for patients with benign vocal fold lesions (BVFLs) after phonomicrosurgery. The study compares the clinical voice outcomes of two protocols, 7-day complete voice rest (CVR) and 3-day CVR followed by 4-day relative voice rest (CVR + RVR), for patients with BVFLs after phonomicrosurgery.

STUDY DESIGN

Prospective, randomized controlled trial.

METHOD

Patients with BVFLs undergoing phonomicrosurgery were recruited prospectively and randomly assigned to either protocol. Outcomes were assessed on objective measures of acoustics (fundamental frequency, frequency range, mean intensity, cepstral peak analysis) and aerodynamics (vital capacity, airflow rate, subglottal pressure, phonation threshold pressure), as well as subjective measures, both provider-reported through the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V), and patient-reported through the Voice Handicap Index (VHI). Clinical measures were collected at three-time points: preoperatively, 1-week postoperatively (on voice rest), and 1-month postoperatively. In addition, adherence was estimated using a vocal dosimeter.

RESULTS

Twenty-five patients were recruited and randomized to 7-day CVR (n = 13) and CVR + RVR regimen (n = 12). Statistically significant changes were found within both groups for subglottal pressure (p = 0.03) and VHI score (p < 0.001) comparing pre-operative baseline to 1-month postoperative follow-up. There were no statistically significant differences between the groups. Regardless of group assignment, a significant decrease in overall severity ratings for the CAPE-V was found by comparing the preoperative scores to postoperative scores at 1-week (p < 0.001) and 1-month (p < 0.001).

CONCLUSION

Both groups improved their overall voice quality comparably 1 month after undergoing phonomicrosurgery as measured by objective and subjective parameters.

LEVELS OF EVIDENCE

2. Laryngoscope, 134:2812-2818, 2024.

Early Initiation of Voice Therapy After Microlaryngeal Surgery - A Randomized Control Study

OBJECTIVE

A prospective single blinded randomized control trial was conducted to study if early initiation of voice therapy after microlaryngeal produces a better voice outcome in patients with benign vocal fold lesions.

METHODS

In this Patients undergoing microlaryngeal surgery for benign vocal fold lesions were recruited for the study and underwent voice evaluation and videostroboscopy preoperatively. Participants were randomised into two groups depending on the duration of voice rest-A (2 days voice rest) and B (5 days voice rest). Following the period of voice rest, voice therapy (tube phonation) was carried out for a month. Postoperative evaluation was done at 6 weeks (over telephone) and 3 months (in person visit) follow up. Outcome measures included the VHI-10, auditory-perceptual voice ratings, acoustic analysis and videostroboscopic vibratory ratings.

RESULTS

Of the 50 subjects, 35 completed the follow up evaluation. The overall compliance to absolute voice rest was 43%. Among the various parameters used for voice evaluation, there was no statistically significant difference between the two groups except for jitter, where the improvement in 5 day voice rest group compared to the 2 day voice rest group was statistically significant.

CONCLUSION

Prolonged voice rest after microlaryngeal surgery is difficult to comply with. As there was no significant difference between the two study groups, clinicians may prescribe a shorter duration of voice rest followed by early initiation of voice therapy after microlaryngeal surgery.

Patient Experience With Absolute Voice Rest Following Phonomicrosurgery: A Qualitative Study

OBJECTIVE(S)

Voice rest is commonly recommended following phonomicrosurgery to minimize vocal fold scarring, but associated quality of life (QoL) is low resulting in poor compliance. This study aimed to explore patients' experiences with voice rest following phonomicrosurgery to identify facilitators and barriers.

METHODS

This qualitative study used prospective, typical case technique for purposive sampling of consecutive patients who underwent voice rest following phonomicrosurgery for benign vocal fold lesions. Participants were enrolled at a single tertiary Laryngology center located at Unity Health Toronto - St. Michael's Hospital from 2020 to 2022. Semi-structured virtual interviews were conducted 4 weeks following patients' surgery. All interview transcripts were transcribed verbatim and underwent thematic analysis. Participant recruitment was stopped once thematic saturation was achieved.

RESULTS

Twenty participants were recruited and 4 withdrew due to scheduling conflicts. Sixteen participants completed interviews, all of whom reported minimal impact of postoperative voice rest on QoL. The participants attributed their success to facilitators such as notifying close contacts of their situation beforehand and adopting nonverbal forms of communication. No participant endorsed a negative attitude toward voice rest. Understanding the rationale for voice rest and the consequences of noncompliance were reported to be effective in encouraging compliance.

CONCLUSION

Overall, the participants tolerated voice rest well owing to facilitators such as early preparation, lifestyle modifications, and understanding the rationale for voice rest. Social disconnect and work demands were barriers of voice rest. Moving forward, facilitators and barriers should be addressed in efforts to optimize the voice rest experience for future patient populations.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:361-366, 2024.

Impact of the Severity of Reinke's Edema on the Parameters of Voice

Objective

This study aimed to classify the degree of edema in patients with Reinke's edema (RE) and examine its impact on their voice parameters using both objective and subjective assessment methods.

Methods

Objective and subjective voice data of 104 patients diagnosed with RE between 2018 and 2021 were evaluated retrospectively. RE is classified into 4 groups (types 1, 2, 3, and 4). The evaluation included videolaryngostroboscopic examination, acoustic voice analysis, and aerodynamic measurements, GRBAS, Voice Handicap Index-10 (VHI-10), Voice-Related Quality of Life Scale (V-RQOL), and Reflux Septum Index (RSI).

Results

Patients with type 1 RE had a significantly lower mean age than those with types 3-4. Although there were no significant differences in acoustic and aerodynamic parameters between the groups, it was observed that F0 and the maximum phonation time decreased as the degree of edema increased. The GRBASTotal, G, and R scores of types 1 and 2 were significantly lower than those of types 3 and 4, as were the scores of type 1 S. There were no statistically significant differences between the RE groups in terms of VHI-10, V-RQOL, and RSI scores.

Conclusion

It has been observed that as the severity of RE increases, voice perception and quality (especially types 3 and 4) are negatively affected. Determining the degree of edema will guide the clinician in both the planning of the intervention phase and the follow-up phase.

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.

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.

Pre- and Postoperative Voice Therapy for Benign Vocal Fold Lesions: An International Electronic Delphi Consensus Study

INTRODUCTION

Voice therapy management of benign vocal fold lesions (BVFLs) is variable and there are currently no clinical guidelines. Poor descriptions of voice therapy interventions lead to unwarranted variation in treatment. Triangulation of the current evidence identifies a number of potential best practice elements, but also a number of outstanding questions to be explored. The aim of this study was to refine and gain global consensus on "best practice" for a pre- and postoperative voice therapy intervention for adults with BVFLs.

METHODS

An international sample of expert voice therapists (n = 42) were recruited to take part in this three-round electronic modified Delphi study. Participants were presented with statements concerning a pre- and postoperative voice therapy intervention. Statements were developed from previous research and based on the TIDieR checklist (eg, why, when, what, how?) Participants rated the extent to which they agreed or disagreed with a statement and gave comments to support their response. Consensus was defined as >75% of participants agreeing or strongly agreeing with a given statement. If consensus was not reached, participant comments were used to generate new statements and were rated in the next round. Stability of consensus between rounds was assessed.

RESULTS

The 42 international experts achieved consensus on 33 statements relating to components of a best practice pre- and postoperative voice therapy intervention for patients with BVFLs. Consensus on statements ranged from 81% to 100%. These statements were explicitly mapped to the TIDieR checklist to ensure that all aspects of the intervention were considered and the questions of "why, what, how, when and individual tailoring" were addressed.

CONCLUSIONS

This study has significantly enhanced our understanding of what should be in a best practice pre- and postoperative voice therapy intervention. It is important to now test these findings for acceptability and feasibility, prior to considering effectiveness research.

Pre- and post-operative voice therapy (PaPOV): Development of an intervention for patients with benign vocal fold lesions

BACKGROUND

Pre- and post-operative voice therapy may improve voice and quality-of-life outcomes for patients undergoing phonosurgery to remove benign vocal fold lesions (BVFLs). However, what constitutes voice therapy in this population is poorly described, resulting in a poor evidence base, lack of clinical guidelines and unwarranted variation in management. In order to develop the evidence base, a robust, iterative process of intervention development work should precede feasibility testing and effectiveness studies.

METHODS & PROCEDURES

Guidance for developing complex interventions, drawing on evidence, theory and modelling, was used to inform the development of a pre- and post-operative voice therapy intervention entitled 'PaPOV'. Data from four sources of evidence were synthesized using a published triangulation protocol. Data from a systematic review, national survey of current practice, expert interview study, and patient and public involvement conversations were used to populate a triangulation matrix, outlining components of a PaPOV. Data were coded to reflect areas of agreement, dissonance and silence with each component of the intervention. Based on this evidence, an assessment of convergence for each intervention component could be made.

OUTCOMES & RESULTS

In total, 61 components of the PaPOV intervention were explored. Of these, 27 were categorized as having stability of consensus according to a priori criteria. A total of 34 failed to meet the criteria. This was more frequently due to silence (27) rather than dissonance (seven) in the data. By evidencing areas of agreement and stability of consensus across data sources, the validity of individual findings has been enhanced. Furthermore, the study has exposed specific areas of the intervention that lack consensus and require exploration through further intervention development studies.

CONCLUSIONS & IMPLICATIONS

This systematic triangulation process has contributed to the development of a PaPOV intervention for patients with BVFLs. Exploration of specific components relating to the intervention will allow outstanding questions to be answered in preparation for feasibility testing.

WHAT THIS PAPER ADDS

What is already known on the subject BVFLs cause dysphonia by preventing vocal fold closure, impacting on vibratory characteristics and increasing compensatory muscle tension. Management for these patients is variable with them being offered phonosurgery, voice therapy, pharmacological management or a combined approach. Pre- and post-operative voice therapy may improve both voice and quality-of-life outcomes. This patient group has unique complexities when considering voice therapy, including surgical preparation, wound healing and epithelial mobilization. What this paper adds to existing knowledge This study uses a robust triangulation process to synthesize current evidence and patient experiences in order to inform the development of a PaPOV. It outlines some of the key components and considerations when delivering pre- and post-operative voice therapy to adults with BVFLs. Furthermore, it serves as a methodological example for intervention development in complex interventions, highlighting key guidance and recommended processes for developing and evaluating complex interventions. What are the potential or actual clinical implications of this work? The 61 components discussed as potential 'ingredients' for a PaPOV enable clinicians to reflect on key considerations when planning and delivering voice therapy to adults with BVFLs. This study highlights the pitfalls both clinically and in research of failing to describe interventions adequately and the benefits of using accurate, specific and agreed terminology in clinical practice, such as that outlined in the Rehabilitation Treatment Specification System (TRSS).

Effects of Different Voice Rest on Vocal Function After Microlaryngeal Surgery: A Systematic Review and Meta-Analysis

OBJECTIVES

To compare the results of a voice handicap index (VHI) scale and acoustic parameters in patients who underwent microlaryngeal surgery followed by either short-duration (voice rest for <7 days) or long-duration (≥7 days) voice rest.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

The PubMed, Embase, and Cochrane Library databases were systematically searched for articles published before March 1, 2021. Randomized controlled trials (RCTs) that measured the voice outcomes of patients after different durations and extents of postoperative voice restriction were included in the meta-analysis.

RESULTS

Four RCTs comprising 112 patients were included in the quantitative meta-analysis. Compared with the long-duration voice rest group, the short-duration group exhibited comparable VHI scores (mean difference [MD], -7.01; 95% CI, -16.12 to 2.09; p = 0.13), maximum phonation time (MD, -2.58; 95% CI, -5.42 to 0.26; p = 0.07), and acoustic variables of jitter (MD, -1.25; 95% CI, -3.43 to 0.94; p = 0.26) and shimmer (MD, -0.79; 95% CI, -2.08 to 0.51; p = 0.24). Subgroup analysis for benign pathology and cold instruments studies demonstrated significantly better VHI scores (MD, -14.45; 95% CI, -26.19 to -2.72; p = 0.02 and MD, -15.98; 95% CI, -28.52 to -3.44; p = 0.01, respectively) in the short-duration group.

CONCLUSIONS

The limited evidence does not demonstrate benefit in voice outcomes from long-duration voice rest and suggests potential unfavorable effects on compliance and quality of life, providing a rationale for short-duration voice rest after microlaryngeal surgery. More studies are required to determine the optimal duration and extent of postoperative voice rest.

LEVEL OF EVIDENCE

1 Laryngoscope, 133:154-161, 2023.

Office-Based Structural Autologous Fat Injection Laryngoplasty for Unilateral Vocal Fold Paralysis

Unilateral vocal fold paralysis (UVFP) is a common cause of incomplete glottic closure, leading to significant somatic and social disabilities. Office-based autologous fat injection laryngoplasty (AFIL) has been proposed as an effective treatment for glottic insufficiency but has not been well-studied for UVFP. We enrolled 23 patients who underwent office-based structural AFIL due to unilateral vocal paralysis at our institution between February 2021 and January 2022. In the procedure, autologous fat was harvested and injected into the vocal fold under the guidance of flexible digital endoscopy for structural fat grafting. The voice handicap index-10 (VHI-10) score and perceptual voice measurements were collected before the operation, 2 weeks postoperatively, and 3 months postoperatively. Twenty-two patients were followed-up for at least 3 months. The VHI-10 score improved significantly from 29.65 ± 8.52 preoperatively to 11.74 ± 7.42 at 2 weeks (p < 0.0001) and 5.36 ± 6.67 at 3 months (p < 0.0001). Significant improvements in grades of dysphonia (p < 0.0001), breathiness (p < 0.0001), and asthenia (p = 0.004) were also noted at 3 months postoperatively when perceptual measurements were investigated. Office-based structural AFIL is an effective treatment for improving voice-related disability for UVFP patients.

Voice rest after vocal fold polyp surgery: A Swedish register study of 588 patients

Objective

To evaluate the impact of voice rest on patient‐reported voice outcome 4 months after vocal fold polyp surgery.

Methods

Preoperative information was collected about age, sex, and smoking habits and the voice handicap index‐10 (VHI‐10). Four months postoperatively, voice rest (total voice rest, spoke single words, and spoke normally), and pre and postoperative voice therapy were reported. This was correlated to voice satisfaction from a two‐category subjective evaluation “satisfied/ not satisfied” and to VHI‐10. Logistic regression models with relative risk for NOT being satisfied with voice after surgery were performed.

Results

Data from 588 patients were available. The group “spoke normally” showed the highest degree of patient satisfaction (92%). Younger patients (<59 years) were more satisfied than older (90% vs. 81.5%). High age and low VHI‐10 scores before surgery were statistically significant for negative voice outcome. Gender or voice rest type did not significantly affect outcome. The largest improvement in VHI‐scores was in the group who spoke normally and least in the group who spoke single words.

Conclusion

We found no significant difference in the two‐category subjective voice outcome depending on voice rest. VHI‐10 showed a statistically significant positive effect on self‐evaluated voice outcome, with the largest improvement in the group with no voice rest. However, the clinical relevance of the VHI changes is unclear. The present study does not show any advantage of total voice rest as compared to relative voice rest or speaking freely. High age and low preoperative VHI scores were significant risk factors for worse voice outcome.

Level of evidence: 4

Voice Handicap Index Changes After Microflap Surgery for Benign Vocal Fold Lesions Are Not Associated With Recommended Absolute Voice Rest Duration

PURPOSE

Voice rest is frequently prescribed after phonosurgery, but optimal type and duration for voice outcomes have not been demonstrated. Studies to date have been characterized by heterogeneity in surgical procedures and laryngeal diagnoses. We sought to analyze the effect of recommended absolute voice rest duration on outcomes of microflap surgery for benign vocal fold lesions. A secondary purpose was to identify patient factors associated with postoperative voice outcomes.

METHOD

Forty-three patients were included in this retrospective review of patients aged 18 years and above who underwent direct microlaryngoscopy with microflap for vocal fold polyp or cyst over a 5-year period at a multidisciplinary voice center. Duration of recommended postoperative absolute voice rest was classified as less than 7 days, 7 days, and more than 7 days. Demographic and vocal hygiene data and voice treatment history were collected. Outcome measures consisted of one pre- and two postoperative Voice Handicap Index (VHI) scores. Effects of recommended voice rest on outcomes were analyzed using mixed models for repeated measures. Effects of patient factors on outcomes were analyzed as exploratory measures. Stroboscopy ratings were analyzed descriptively.

RESULTS

Thirteen patients were recommended 7 days of absolute voice rest, 15 were recommended less than 7 days, and 15 were recommended more than 7 days. Postoperatively, VHI scores significantly improved for all patients. Voice rest as a continuous variable was associated with the Functional subscale score in the short term, but there was no effect on VHI total score and no longer term effect of voice rest on any outcome. Age, sex, and preoperative voice therapy were associated with at least one VHI subscale score on at least one time point.

CONCLUSION

VHI outcomes of microflap surgery for polyps and cysts do not differ by duration of recommended absolute postoperative voice rest.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.19178459.

Mitigating the Effects of Acute Vocal Exertion in Individuals With Vocal Fatigue

OBJECTIVES/HYPOTHESIS

To investigate the effects of acute vocal exertion on individuals with vocal fatigue and to determine whether semi-occluded vocal tract exercises (SOVTEs) are more effective than vocal rest in mitigating acute effects.

STUDY DESIGN

Prospective, repeated-measures design.

METHODS

On consecutive days, 10 individuals (6 males, 4 females) with scores indicating vocal fatigue on the Vocal Fatigue Index completed two 10-minute vocal exertion tasks. Vocal rest or SOVTEs were interspersed in counterbalanced order between exertion tasks. Respiratory kinematic, acoustic, aerodynamic, and self-perceptual measures were collected at baseline, following vocal exertion, following SOVTE/vocal rest, and following the second exertion task.

RESULTS

Acute vocal exertion worsened phonation threshold pressure (P < .001) and vocal effort (P < .001) and reduced maximum fundamental frequency (P < .001). Speech was terminated at lower lung volumes following vocal exertion (decreased lung volume termination [LVT], P < .001). Exertion-induced changes in vocal effort and LVT were significantly reversed by both vocal rest and SOVTE. Detrimental changes in voice measures reoccurred following the second vocal exertion task. SOVTE and vocal rest protected against changes in respiratory kinematics when vocal exertion was resumed.

CONCLUSIONS

Vocal exertion impacted laryngeal, respiratory, and self-perceptual measures in individuals with vocal fatigue. Both SOVTE and vocal rest partially mitigated changes in voice measures and prompted more efficient respiratory strategies that were maintained when vocal exertion resumed. These data increase our understanding of how individuals with vocal fatigue respond to vocal exertion tasks and offer preliminary guidance for optimal clinical recommendations.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:2732-2739, 2021.

The role of voice rest after micro-laryngeal surgery for benign vocal fold lesions

PURPOSE

To compare post-operative vocal outcomes of a voice rest regimen versus no voice restrictions following micro-laryngeal surgery for benign glottic lesions.

METHODS

This was a combined prospective and retrospective cohort study on 167 patients who underwent micro-laryngeal surgery for benign focal fold lesion removal. Participants were divided into two regimens: standard voice rest (n = 92) or no voice restriction (n = 75). The primary outcome was post-operative vocal improvement, evaluated using voice handicap index questionnaire (VHI-10), GRBAS scale, and computerised acoustic analysis (shimmer, jitter, and the harmonic-to-noise ratio). The secondary outcome was emergence of vocal fold mucosal abnormalities in the immediate post-operative period. Parameters were collected at baseline and at the last clinical visit.

RESULTS

There was no statistically significant difference between the voice rest and no-voice rest groups regarding baseline parameters of age, gender, laryngeal pathology, and voice use. Improvement in GRBAS scale values and VHI-10 scores between pre- and post-operative periods between groups did not demonstrate any statistically significant differences (P = 0.5303 and P = 0.1457, respectively). Similarly, the results of computerized voice analysis also showed no differences between groups in terms of shimmer (P = 0.9590), jitter (P = 0.5692), and harmonic-to-noise ratio (P = 0.1871). No correlation was found between the post-operative vocal fold's mucosal abnormalities and the type of voice rest regimen.

CONCLUSION

Voice quality and wound healing were similar regardless of the type of voice rest regimen applied. No voice rest at all was as good as voice rest after micro-laryngeal surgery.

Restoration Strategies Following Short-Term Vocal Exertion in Healthy Young Adults

Purpose This study aims to investigate the effects of a 10-min vocal exertion task on voice and respiratory measures, to determine whether restorative strategies can mitigate these effects after cessation of exertion, and to assess whether these strategies continue to reduce these detrimental effects when vocal exertion is resumed. Method A prospective, repeated-measures design was used. On consecutive days, 20 participants (equal men and women) completed two vocal exertion tasks separated by 10 min of restoration strategies: vocal rest or controlled phonation (low-level tissue mobilization using straw phonation). Voice and respiratory data were collected at baseline, following the first exertion task, after restoration strategies, and after the second exertion task. Outcome measures included (a) vocal effort, (b) phonation threshold pressure, (c) maximum and minimum fundamental frequencies, (d) cepstral peak prominence of connected speech, (e) lung volume initiation and termination, (f) percent vital capacity expended per syllable, and (g) number of syllables per breath group. Results A worsening of phonation threshold pressure (p < .001), vocal effort (p < .001), and increase of minimum fundamental frequency (p = .007) were observed after vocal exertion. Lung volume initiation (p < .001) and lung volume termination (p < .001) increased. These changes were largely reversed by restoration strategies, but only controlled phonation prevented exertion-induced changes in respiratory kinematic measures on a subsequent vocal exertion task. Conclusions Exertion-induced voice changes occur rapidly and may be mitigated by either controlled phonation or vocal rest. Controlled phonation is recommended as a superior strategy due to evidence of a protective effect on a successive vocal exertion task.

In vitro mechanical vibration down-regulates pro-inflammatory and pro-fibrotic signaling in human vocal fold fibroblasts

INTRODUCTION

Voice rest following phonotrauma or phonosurgery has a considerable clinical impact, but clinical recommendations are inconsistent due to inconclusive data. As biopsies of the vocal folds (VF) for molecular biology studies in humans are unethical, we established a new in vitro model to explore the effects of vibration on human vocal fold fibroblasts (hVFF) in an inflammatory and normal state, which is based on previously published models.

METHODS

By using a phonomimetic bioreactor we were able to apply predefined vibrational stress patterns on hVFF cultured under inflammatory or normal conditions. Inflammatory and pro-fibrotic stimuli were induced by interleukin (IL)1β and transforming growth factor (TGF)β1, respectively. Mechanical stimulation was applied four hours daily, over a period of 72 hours. Outcome measurements comprised assessment of extracellular matrix (ECM)-related components, angiogenic factors, and inflammatory and fibrogenic markers on gene expression and protein levels.

RESULTS

Under inflammatory conditions, the inflammatory cytokine IL11, as well as the myofibroblast marker alpha smooth muscle actin (α-SMA) were significantly reduced when additional vibration was applied. The desirable anti-fibrotic ECM component hyaluronic acid was increased following cytokine treatment, but was not diminished following vibration.

CONCLUSION

Our experiments revealed the effect of vibrational stress on hVFF in an inflammatory state. Elevated levels of certain pro-inflammatory/pro-fibrotic factors could be mitigated by additional vibrational excitation in an in vitro setting. These findings corroborate clinical studies which recommend early voice activation following an acute event.

Laryngeal Image Processing of Vocal Folds Motion

This review provides a comprehensive compilation, from a digital image processing point of view of the most important techniques currently developed to characterize and quantify the vibration behaviour of the vocal folds, along with a detailed description of the laryngeal image modalities currently used in the clinic. The review presents an overview of the most significant glottal-gap segmentation and facilitative playbacks techniques used in the literature for the mentioned purpose, and shows the drawbacks and challenges that still remain unsolved to develop robust vocal folds vibration function analysis tools based on digital image processing.

The Therapeutic Effects of Straw Phonation on Vocal Fatigue

OBJECTIVES

Straw phonation has been investigated for its vocal warm-up effects on healthy populations and therapeutic effects on voice patients. The purpose of this article was to determine whether it is beneficial for vocal fatigue.

STUDY DESIGN

Prospective cohort study METHODS: Twenty-five healthy participants were recruited into 1-hour vocal loading tasks followed by 10-minute vocal rest or straw phonation on 2 different days. Various parameters including phonation threshold pressure (PTP), mean airflow, closed quotient (CQ), current speaking effort level (EFFT), and laryngeal discomfort (DISC) were acquired at baseline, after vocal load, and after the intervention.

RESULTS

Increased PTP, EFFT, and DISC were observed after vocal load. Decreased PTP, EFFT, and DISC were then acquired after both vocal rest or straw phonation. More significant improvements were obtained in straw phonation when compared with vocal rest. Additionally, significantly increased mean flow and decreased CQ were obtained after straw phonation when compared to vocal rest.

CONCLUSIONS

Straw phonation has the potential to adjust aerodynamics within the vocal tract leading to improved vocal efficiency, optimized vibration mode, and attenuated vocal fatigue. This study provided a promising treatment for vocal fatigue that could have wide clinical relevance to voice users with high voice demands.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:E674-E679, 2020.

Management of benign vocal fold lesions: current perspectives on the role for voice therapy

PURPOSE OF REVIEW

Benign vocal fold lesions (BVFLs) cause dysphonia by preventing full vocal fold closure, interrupting vibratory characteristics and increasing compensatory muscle tension. Management includes phonosurgery, voice therapy, pharmacological treatment or more commonly a combination of these interventions. This review aims to present current perspectives on the management of BVFLs, particularly exploring the role of voice therapy.

RECENT FINDINGS

The review highlights variation in the management of BVFLs. There is evidence that phonosurgery is a well tolerated and effective intervention for BVFLs. Primary voice therapy can frequently prevent surgery in vocal fold nodules and some types of polyps. Used as an adjunct to phonosurgery, preoperative and postoperative voice therapy can improve patient-reported outcomes and acoustic parameters of the voice. However, heterogeneity of studies and poor descriptions of intervention components prevent a robust analysis of the impact of voice therapy.

SUMMARY

The current evidence consists of low-level studies using mixed aetiology groups, which compromises internal and external validity. There are a few exceptions to this. Poor reporting and heterogeneous methodologies lead to difficulties determining the components of a voice therapy intervention for this population. Consequently, we are unable to evaluate, which intervention elements are beneficial to patients.

Role of voice rest following laser resection of vocal fold lesions: A randomized controlled trial

OBJECTIVES/HYPOTHESIS

Voice rest is often prescribed following phonosurgery by most surgeons despite limited empiric evidence to support its practice. This study assessed the effect of postphonosurgery voice rest on vocal outcomes.

STUDY DESIGN

Prospective, randomized controlled trial.

METHODS

Patients with unilateral vocal fold lesions undergoing CO₂ laser excision were recruited in a prospective manner and randomized into one of two groups: 1) an experimental arm consisting of 7 days of absolute voice rest, or 2) a control arm consisting of no voice rest. The primary outcome measure was the Voice Handicap Index-10 (VHI-10) questionnaire. Secondary outcomes included aerodynamic measurements (maximum phonation time), acoustic measures (fundamental frequency, jitter, shimmer, and harmonic-to-noise ratio), and auditory-perceptual measures. Primary and secondary outcomes were assessed preoperatively and reassessed postoperatively at the 1- and 3-month follow-up. Patient compliance to voice rest instructions were controlled for using subjective and objective parameters.

RESULTS

Thirty patients were enrolled with 15 randomized to each arm of the study. Statistical analysis for the entire cohort showed a significant improvement in the mean preoperative VHI-10 compared to postoperative assessments at 1-month (19.0 vs. 7.3, P < .05) and 3-month (19.0 vs. 6.2, P < .05) follow-up. However, between-group comparisons showed no significant difference in postoperative VHI-10 at either time point. Similarly, secondary outcome measures yielded no significant difference in between-group comparisons.

CONCLUSIONS

Our study shows no significant benefit to voice rest on postoperative voice outcomes as determined by patient self-perception, acoustic variables, and auditory-perceptual analysis.

LEVEL OF EVIDENCE

1b CLINICAL TRIAL NUMBER: NCT02788435 (clinicaltrials.gov) Laryngoscope, 130:1750-1755, 2020.

Voice rest and sick leave after phonosurgical procedures: surveys among European laryngologists and phoniatricians

Purpose

After surgery of vocal folds, almost every patient will need some voice rest. It is common to recommend total silence for some days, followed by less restricted voice use for variable periods. By now, we do not know how voice rest affects the healing process or the current practise in Europe.

Methods

Members of the European Laryngological Society (2012) and the Union of European Phoniatrics (2018) were sent a web-based questionnaire which included two patient cases with a short history and a still picture. The respondents were asked about the postoperative recommendation of absolute voice rest and sick leave.

Results

Over 90% of the respondents would recommend absolute voice rest after removing a polyp or after mucosal repair of Reinke’s oedema. For both cases, the mean length of recommended absolute voice rest among UEP members was 4 days (range 0–10 days) and among ELS members was 5 days (range 0–14 days). The recommended sick leave ranged from 0 to 35 days. The mean figures suggested by ELS members for the receptionist with Reinke’s oedema were 12 days and for the teacher with a polyp 13 days. On average, UEP members recommended 14 days of sick leave for both cases.

Conclusion

The present scientific evidence is scant, but does not support for prolonged (over 3 days) absolute voice rest after simple phonosurgery. So far, there are no studies that could show absolute voice rest to be superior over relative voice rest. According to the present survey, there is considerable variation in recommending voice rest and sick leave after the removal of benign mucosal lesions. Many European laryngologists suggest voice rest that is longer and stricter than the present scientific literature supports.

Visual and Automatic Evaluation of Vocal Fold Mucosal Waves Through Sharpness of Lateral Peaks in High-Speed Videokymographic Images

INTRODUCTION

The sharpness of lateral peaks is a visually helpful clinical feature in high-speed videokymographic (VKG) images indicating vertical phase differences and mucosal waves on the vibrating vocal folds and giving insights into the health and pliability of vocal fold mucosa. This study aims at investigating parameters that can be helpful in objectively quantifying the lateral peak sharpness from the VKG images.

METHOD

Forty-five clinical VKG images with different degrees of sharpness of lateral peaks were independently evaluated visually by three raters. The ratings were compared to parameters obtained by automatic image analysis of the vocal fold contours: Open Time Percentage Quotients (OTQ) and Plateau Quotients (PQ). The OTQ parameters were derived as fractions of the period during which the vocal fold displacement exceeds a predetermined percentage of the vibratory amplitude. The PQ parameters were derived similarly but as a fraction of the open phase instead of a period.

RESULTS

The best correspondence between the visual ratings and the automatically derived quotients were found for the OTQ and PQ parameters derived at 95% and 80% of the amplitude, named OTQ₉₅, PQ₉₅, OTQ₈₀ and PQ₈₀. Their Spearman's rank correlation coefficients were in the range of 0.73 to 0.77 (P < 0.001) indicating strong relationships with the visual ratings. The strengths of these correlations were similar to those found from inter-rater comparisons of visual evaluations of peak sharpness.

CONCLUSION

The Open time percentage and Plateau quotients at 95% and 80% of the amplitude stood out as the possible candidates for capturing the sharpness of the lateral peaks with their reliability comparable to that of visual ratings.

Absolute or relative voice rest after phonosurgery: a blind randomized prospective clinical trial

OBJECTIVES

The first aim, was to compare participant compliance with postoperative voice rest advice in two groups. The second aim was to compare vocal function and recovery in the short-term, seven days post-surgery and in the long-term, 3-6 months post-surgery.

DESIGN

Preliminary randomized prospective blind clinical trial.

METHODS

Twenty patients scheduled for surgery for benign vocal fold lesions were randomized into seven days of absolute or relative voice rest. Compliance with voice rest advice was monitored with a voice accumulator for seven days following surgery. Vocal recovery was tracked through (a) self-perceived vocal function, (b) perceptual assessments of voice recordings and (c) visual assessment of high resolution and high speed digital imaging (d) vocal stamina and reaction to vocal loading, explored with a vocal loading task.

RESULTS

The absolute voice rest group phonated significantly less than the relative voice rest group during seven days post-surgery, but they were not silent. The absolute voice rest group self-reported more difficulty with compliance than the relative voice rest group. The relative voice rest group coped with significantly more vocal loading at long-term check-up. In the short-term the absolute voice rest group improved morphological recovery to a significant degree, however relative voice rest renders superior long-term recovery.

CONCLUSIONS

Absolute voice rest is difficult to comply with. Neither short-term, nor long-term vocal recovery differed significantly between groups. Within-group comparisons showed significant improvements in vocal stamina, immediate recovery from vocal loading and self-assessments of voice problems only for the group with recommended relative voice rest.

A phase I/II exploratory clinical trial for intracordal injection of recombinant hepatocyte growth factor for vocal fold scar and sulcus

Vocal fold scar and sulcus are intractable diseases with no effective established treatments. Hepatocyte growth factor (HGF) has preclinically proven to have potent antifibrotic and regenerative effects on vocal fold scar. The current Phase I/II clinical trial aims to examine the safety and effectiveness of intracordal injection of a recombinant human HGF drug for patients with vocal fold scar or sulcus. This is an open-label, dose-escalating, first-in-human clinical trial. Eighteen patients with bilateral vocal fold scar or sulcus were enrolled and divided into three groups: Step I received 1 μg of HGF per vocal fold; Step II received 3 μg of HGF; and Step III received 10 μg of HGF. Injections were administered once weekly for 4 weeks. The protocol treatment was performed starting with Step I and escalating to Step III. Patients were followed for 6 months post-treatment. Local and systemic safety aspects were examined as primary endpoints, and therapeutic effects were assessed as secondary endpoints using voice handicap index-10; maximum phonation time; vocal fold vibratory amplitude; grade, rough, breathy, asthenic, strained scale; and jitter. The results indicated no serious drug-related adverse events in either the systemic or local examinations. In whole-subject analysis, voice handicap index-10, vocal fold vibratory amplitude, and grade, rough, breathy, asthenic, strained scale were significantly improved at 6 months, whereas maximum phonation time and jitter varied. There were no significant differences in phonatory data between the step groups. In conclusion, intracordal injection of a recombinant human HGF drug was safe, feasible, and potentially effective for human patients with vocal fold scar or sulcus.

Voice rest after laryngeal surgery: what's the evidence?

PURPOSE OF REVIEW

This article aims to review previous research reports and to summarize current strategies for the optimal duration of voice rest and the effect of phonatory stimulation after phonomicrosurgery.

RECENT FINDINGS

Voice rest is commonly recommended after laryngeal surgery to prevent worsening of vocal fold injuries. However, there are no established standard protocol for voice rest, and the type and duration of voice rest vary among clinicians. The most effective duration of voice rest is unknown. Recently, early vocal stimulation was recommended as a means to improve wound healing, on the basis of the basic and clinical researches.

SUMMARY

It seems that early vocal stimulation may enhance the wound healing process in the vocal fold. More basic and clinical researches are warranted to investigate appropriate timing of initiation of stimulation, as well as the type and amount of stimulation that are available for human.