INVITED REVIEW ARTICLE


https://doi.org/10.5005/jp-journals-10001-1520
International Journal of Head and Neck Surgery
Volume 13 | Issue 1 | Year 2022

Care of the Professional Voice


Michelle M Bretl1, David E Rosow2

1Department of Otolaryngology, Division of Speech Pathology, University of Miami Miller School of Medicine, Miami, Florida USA

2Department of Otolaryngology, Division of Laryngology and Voice, University of Miami Miller School of Medicine, Miami, Florida USA

Corresponding Author: David E. Rosow, Department of Otolaryngology, Division of Laryngology and Voice, University of Miami Miller School of Medicine, Miami, Florida USA Phone: +1 305-243-2587, e-mail: DRosow@med.miami.edu

ABSTRACT

Aim: This article aims to identify the unique requirements in evaluating and treating professional voice users with voice complaints.

Background: Professional or occupational voice users make up a large portion of a laryngological caseload. These individuals, including teachers, performers, salespeople, etc., rely on proper vocal function every day to carry out the demands of their job. As a result, these patients may require a more comprehensive clinical evaluation and intervention given the nature of their careers.

Patient care/Techniques: Otolaryngologists should consider the use of videolaryngostroboscopy to assess the subtleties of vocal fold function and vibration. Often, close collaboration with a speech pathologist is most beneficial to these patients to improve the overall health and functioning of the voice and promote longevity of proper voice use. A variety of vocal pathologies are seen in the professional voice population, including laryngitis, benign vocal fold lesions, and functional disorders such as muscle tension dysphonia. Management and treatment will depend not only on the findings from the evaluation, but also access to a collaborative voice team and the patient's wishes related to their profession. Voice rest is generally only implemented in specific cases where avoiding vocal fold collision is crucial to healing. Voice therapy is often warranted both for rehabilitation and learning appropriate compensatory strategies and healthier voicing behaviors. Depending on the evaluation findings and the comfort level of the provider, medication or surgical intervention may be most appropriate for certain patients.

Clinical significance/Conclusion: Professional voice users are frequently seen by otolaryngologists due to the essential role of their voices and the high demands often required. Providers should be knowledgeable in the assessment and treatment of voice disorders. If necessary, providers should establish a voice care team in the area that can appropriately assist these patients.

How to cite this article: Bretl MM, Rosow DE. Care of the Professional Voice. Int J Head Neck Surg 2022;13(1):18-26.

Source of support: Nil

Conflict of interest: None

Keywords: Occupational voice, Professional voice, Vocal folds, Voice evaluation, Voice rest, Voice therapy

INTRODUCTION

When considering the phrase professional voice user , singers or actors may come to mind initially because of the intricacies and projection often required of their voices. However, professional voice users extend far beyond those involved in the arts; any person who requires their voice to do their job is considered a professional voice user. While this includes singers and other performers, teachers, salespeople/telemarketers, counselors, medical professionals, lawyers, religious clergy, and broadcasters are frequently seen in the voice clinic. It is estimated that professional voice users make up approximately one-third of the workforce worldwide.1

The term occupational voice user has also been used to differentiate between those who use their voice for performance and require unique qualities of voice (professional voice users) and those who rely heavily on their typical speaking voice just to do their job, such as teachers, salespeople, and clergy (occupational voice users). For the purpose of continuity and consistency, the term professional voice user will be used in this paper to refer to all professional and occupational voice users.

Demographics and Prevalence

Professional voice users are naturally at higher risk for voice disorders due to the vocal demands required from them daily and account for a significant portion of patients seen in a typical voice clinic. Table 1 demonstrates information outlining an example of professional voice users within a typical voice clinic caseload.2 The authors reported that teachers accounted for nearly 20% of a standard voice clinic load, salespeople for about 10%, and singers for about 11%. While salespeople do account for nearly 13% of the U.S. working population, teachers only cover about 4% and singers only 0.02%, which begins to demonstrate the skewed nature of those affected by voice difficulty.

Table 1: Occupations at risk for voice disorders population vs clinic percentages
Occupation % of U.S. population % of clinic load
Salespeople 12.97 10.3
Telemarketers 0.78 2.3
Factory workers 14.53 5.6
Clerical workers 10.57 8.6
Teachers 4.20 19.6
Counselors 0.19 1.6
Singers 0.02 11.5

Source: Adapted from Titze et al. (1997)2

The prevalence of voice disorders in teachers as professional voice users has been analyzed at some length, especially compared to the general population. In the general population, it has been reported that nearly 30% of adults has experienced a voice problem in their life, and around 7% have a current voice problem.3 Bhattacharyya reported similar findings of prevalence, indicating 1 in 13 adults annually will experience voice difficulty.4 Smith et al. determined that 32% of teachers reported an episode of voice difficulty at some point in their career compared to only 1% in nonteachers group.5 Additionally, about 20% of teachers missed work for voice problems compared to only 4% of not-teachers. In 2004, Roy et al. reported on the prevalence of current voice problems: 11.0% of teachers and 6.2% of nonteachers. The prevalence of voice disorders during their lifetime was 57.7% for teachers versus 28.8% for nonteachers.6 These findings are comparable to those reported by Angelillo et al.; this study found that 8.7% of teachers reported a current voice problem, while 2.9% of nonteachers admitted to a current voice problem. The prevalence of voice difficulty at some point during their lifetime was 51.4% for teachers vs 25.9% for those who were not teachers.7 While there may be some variability in the exact prevalence of voice problems in the general public and in teachers specifically, there is a notable discrepancy between the two populations (Table 2).

Table 2: Prevalence of voice disorders in teachers-a review
Study % of teachers with voice disorders % of nonteachers with voice disorders
Current voice disorders
Behlau, 2011 12 8
De Jong, 2006 18 8
Roy, 2004 11 6
Smith, 1997 15 6
Brinca, 2014 52 48
Sala, 2001 17 6
Sliwinska-Kowalska, 2006 33 10
Voice disorders in the last year
Thomas, 2006 54 37
Pekkarinen, 1992 80 71
Cantor-Cutiva, 2015 71 54
Voice disorders in the lifetime
Roy, 2004 58 29
Smith, 1998 18 11

Source: Adapted from Cantor-Cutiva (2018)22

The prevalence of voice disorders in singers is variable and may depend on the genre of singing, but there is a paucity of research related to differences between genres. Pestana et al. conducted a review and meta-analysis of self-reported voice disorders in singers; prevalence was noted to be 46.09% among all singers. Interestingly, singing students had significantly lower prevalence while singing teachers and professionals (classical and nonclassical) reported higher prevalence.8 Phyland et al. compared singers across three genres (opera, musical theatre, and nonrock contemporary) and compared with nonsinger controls. The singers were found to have a 44% prevalence of voice disorders vs 21% in controls, but no difference was found between the different genres.9 In contrast, Lloyd et al. studied the prevalence of vocal fold pathologies in singing students across the same three genres. Results from this study revealed a significantly higher prevalence of vocal fold pathology among contemporary and musical theatre students, with no evidence of vocal fold pathologies with classical singer students.10 Singers may also have acting demands, while actors may not be required to sing, depending on the role or job. Kitch and Oates compared the effects of vocal fatigue in actors and singers in a survey study. Actors reported challenges with projecting the voice when experiencing vocal fatigue whereas singers noted that aspects such as their pitch range were most affected. This study begins to address the need to consider the nuances of the voice and the possible impact of a voice problem on certain individuals, depending on their occupation and resulting voice demands.11

Literature has emerged regarding the prevalence of voice disorders in other populations, including aerobics/fitness instructors,12-14 actors,15 and call center operators/telemarketers,16,17 among other professional voice users. These populations, along with teachers and singers, continue to be of concern due to the consideration of voice demands associated with the occupation, vocal load, and environment related to the occupation.

Voice disorders due to occupations are well-represented in voice clinics and require a multidisciplinary assessment with stroboscopy. Phyland and Miles discussed the importance of understanding the demands of each occupation and how that informs the onset, progression, and recovery of the voice disturbance.18 It is not uncommon for professional voice users to require some degree of treatment, whether that includes voice therapy and/or medical intervention, but the patient’s priority is often a quick recovery and returns to work.

Laryngeal Anatomy and Physiology

In order to appropriately diagnose and treat these professional voice users, it is imperative to fully understand the basic anatomy and physiology of the larynx and voice production. A comprehensive review of this subject is beyond the scope of this paper, but a brief summary will be provided here. The production of the human voice can be broken down into three major components: a power source, a vibrator, and a resonator. When voice is produced, the respiratory system serves as the power source, the vocal folds vibrate to produce sound (which can be modified to many different frequencies or perceived pitches), and the pharynx, oral cavity, nose, and sinuses (i.e., the vocal tract) to shape and/or amplify the sound. The voice is often compared to other instruments; however, one must consider that the voice as an instrument cannot be “put away” and it is generally the main means of communication. The voice can also be greatly affected by other body systems and emotions, such as illness (mental or physical) and stress.19 When considering the additional demands of extensive voice projection or singing, there is increased importance of the interaction between the vocal tract, the respiratory muscles, the intrinsic and extrinsic muscles of the larynx, and even the nervous system. The efficient vocal function relies not only on each of these components functioning correctly independently, but also on proper coordination between the various systems and components.

The vocal folds are the vibratory source of the voice that can be stretched or contracted to various frequencies (or perceived pitches) during voice production. Nearly half a century ago, Dr Minoru Hirano described the five layers that create the entire vocal folds, including the epithelium; superficial, intermediate, and deep layers of the lamina propria; and the thyrovocalis muscle (Fig. 1).20 These layers become crucial when considering the location and depth of certain vocal fold pathologies and implications for surgical intervention.

Fig. 1: Layered microstructure of the human vocal fold.23

The relationship between vocal fold injury and changes in the vocal fold architecture and composition has been of interest to clinicians and researchers for years. A crucial component found within the layers of the lamina propria is called the extracellular matrix, and hyaluronic acid is known to be a key substance within this matrix. In acute vocal fold injury, a notable decrease in hyaluronic acid has been found, which leads to increased phonation threshold pressure and increased vocal fatigue.21 This is of interest specifically for professional voice users due to the increased prevalence of voice disorders and the potential for vocal fatigue and injury with increased voice demands.

Laryngeal muscles are classified into two main categories: intrinsic and extrinsic laryngeal muscles. Intrinsic muscles are crucial for vocal function, as these muscles dictate abduction and adduction, adjusting the length of the vocal folds, and tensing or relaxing the vocal folds themselves. Beyond the more well-known intrinsic muscles of the larynx, there are extrinsic laryngeal muscles that have one attachment point within the larynx and the other to a location outside of the larynx. These muscles do not control the fine movements within the larynx, but rather affect the gross movements of the larynx, including laryngeal elevation and depression. The extrinsic laryngeal muscles can certainly impact vocal function and may be the primary culprits in certain diagnoses, such as muscle tension dysphonia, which is discussed more below.

Voice Evaluation

As with any typical evaluation, a thorough case history is crucial to fully understand the onset and cause of the voice difficulty as well as the course of a voice disorder over time. Specific to a case history within a voice evaluation, it would be prudent to understand if the onset of voice difficulty was sudden or gradual and whether there was an inciting event, such as an illness, stressful event, increase in vocal load, job change, etc. The patient should describe elements of their vocal hygiene or health, including any smoking history, illicit drug use, hydration, caffeine intake, overt reflux symptoms or history, sleep patterns/habits. Phonotrauma is a term that is used extensively regarding changes to the vocal fold mucosa that can occur during high-effort vibration.24 Phonotraumatic behaviors may include talking too extensively or too loudly, talking over noise or yelling/screaming, coughing and throat clearing, and speaking or singing outside a comfortable pitch range. Phonotrauma replaced vocal abuse to be more descriptive and decrease the concern of physical harm or mistreatment.

When evaluating professional voice users, providers must have a clear understanding of each patient’s vocal load and voice demands. This includes the number of hours of voice used per day and days per week, the environment in which they use the voice, and access to amplification or the need to project the voice. It may also be necessary to discuss voice use outside of their occupation to understand whether their home or social life might be contributing to any voice difficulty. The discussion of case history can also serve as a time to establish rapport with the patient, which is a key component of motivational interviewing, and ultimately treatment follow through.25

Additionally, as part of the intake and case history, the patient should be provided with appropriate questionnaires related to the voice, such as the Voice Handicap Index (VHI),26 the shortened VHI-10,27 or the Voice-related Quality of Life scale.28 These scales have been translated and validated in numerous languages, and there are pediatric versions available as well. These scales can provide additional insight into the effect of the voice difficulty on the patient’s quality of life. It is possible that the patient is not very bothered or affected by their voice but may frequently be asked by others about their hoarse voice quality. This patient would have a unique motivation for seeking services compared to a professional voice user who is significantly affected by their voice difficulty and is experiencing a loss of income.

Following a thorough case history and completion of voice-related questionnaires, the next steps of the evaluation would be dependent upon the nature of the clinic. Voice patients often benefit from a multidisciplinary evaluation, including an otolaryngologist (ENT) and a speech-language pathologist (SLP). While appropriate treatment will depend upon a specific diagnosis, professional voice users require long-term functioning of their voice to continue with their careers. Because of this, SLP with knowledge in voice disorders can provide both education and physical exercises to improve the overall health of the voice, better coordinate vocal function, and help the patient avoid recurrence of preventable voice disorders.

In a collaborative voice clinic with a SLP, acoustic and aerodynamic measures will be taken as part of a comprehensive evaluation. There is present technology to provide a highly specific evaluation of these measures. Many voice clinics use an acoustic system such as Computerized Speech Lab (CSL), from PENTAX Medical (Montvale, USA),29 which is compatible with many programs to measure myriad acoustic measures (Fig. 2). Fortunately, there is also a free acoustic analysis program available online called Praat (Amsterdam, The Netherlands) which provides essentially the same measures.30 More recently, there have been advances in mobile phone technology and applications, and many clinicians who do not have access to these other programs may use their mobile phones to establish initial acoustic measures. With any of these setups, it is recommended to include a microphone and preamplifier along with the recording device to ensure high-quality and reliable recording.

Fig. 2: Computerized Speech Lab from PENTAX Medical

Acoustic measures of interest for professional voice users can include fundamental frequency during the continuous speech, vocal intensity during a conversation, and a measure called cepstral peak prominence (CPP). CPP was first described by Hillenbrand et al. as a means to quantify dysphonia.31 This measure is used often to describe the severity of dysphonia and functions well as an objective measure that can be compared to subjective measures, such as auditory perception of vocal quality. Other short-term perturbation measures have been used (e.g., jitter and shimmer), but there is little evidence that supports increased perturbation measures corresponding with perceptually dysphonic voices.

When considering certain professional voice users, there may be additional acoustic measures required. For singers, it may be necessary to establish a comfortable frequency range, particularly if the patient reports that they have noticed a decrease in their pitch range. For teachers or fitness instructors, it may be beneficial to take measures of maximum vocal intensity because these populations often need to project their voices. These measures are meant to be informative and imitate functional voice use as much as possible, so it is imperative to tailor the evaluation to the individual patient.

Aerodynamic measures may also be part of an SLP voice evaluation. These measures provide valuable information related to airflow and pressure associated with voice production. Including these measures in evaluation can further identify objective measures that may explain an individual’s voice difficulty or disorder. High-tech systems are available for those who frequently see voice patients; PENTAX Medical markets an aerodynamic system called the Phonatory Aerodynamic System (PAS).29 This high-tech system can provide measures such as average airflow during a sustained vowel, estimated subglottal pressure to initiate phonation, and estimated laryngeal resistance during phonation (Fig. 3). These measures may inform and/or support visualized degrees of vocal fold closure and muscle tension.

Fig. 3: PENTAX Medical Phonatory Auditory System Model 6600. Accessed 9 May 2021 from Https://www.pentaxmedical.com/pentax/en/97/1/phonatory-aerodynamic-system-pas-model-6600

Unfortunately, this system is very costly; because of this, there are low-tech acoustic measures that can be used, but only provide a rough estimate due to the indirect nature of measurement. One measure is maximum phonation time (sustained “ah” as long as possible) to estimate lung capacity and glottic closure. Another measure, initially described by Eckel and Boone is called the s/z ratio.32 This ratio takes the length of time a patient can sustain “s” divided by the length of time they can sustain “z.” The ratio is closer to 1.0 for healthy voice users and higher for those experiencing voice difficulty.

Another integral portion of a voice evaluation for professional voice users is the auditory-perceptual assessment of the patient’s voice quality. This can be done by the ENT and/or SLP and is recommended to establish an initial severity of the voice disorder and use to monitor progress over time. Two frequently-used tools include the overall dysphonia grade, roughness, breathiness, asthenia, and strain (GRBAS) scale33 and the Consensus Auditory Perceptual Evaluation-Voice (CAPE-V) scale.34 According to Nemr et al., both scales demonstrate a strong intrarater consensus and a strong correlation between the two scales.35 Of note, evaluators reported that the GRBAS scale was faster, and the CAPE-V was more sensitive to small changes in the voice. Generally, SLPs tend to use the CAPE-V as they receive some exposure to this scale in their graduate education.

While the previously mentioned portions of the voice evaluation all provide valuable information regarding vocal function, laryngeal visualization may be the most crucial part of voice evaluation overall. Auditory-perceptual measures are subjective and can be provider-dependent, while acoustic and aerodynamic measures are objective but only achieve an indirect measurement. Paul et al. reported that diagnostic accuracy based on history and physical examination alone was only 5%; this increased to over 68% with use of laryngeal imaging.36 Vocal fold visualization provides a real-time view of what is happening at the level of the vocal folds during phonation.

Over the years, many methods of laryngeal visualization have been described, including mirror examination, laryngoscopy (rigid or flexible), laryngovideostroboscopy, videokymography, and high-speed videoendoscopy. With advances in technology, mirror examination is no longer considered adequate to visualize the vocal folds. Videokymography and high speech videoendoscopy provide exceptionally clear videos given the sampling rates but are not generally used in a clinic setting, likely due to cost and computer storage required.

Many ENT providers utilize endoscopes in their practice to manage various disorders related to the nose and sinuses and may use the same equipment for vocal fold visualization. However, the use of videostroboscopy for subtle changes along the vocal fold mucosa or in vocal fold function cannot be captured with laryngoscopy with continuous light due to the speed at which the vocal folds vibrate (Fig. 4). Videolaryngostroboscopy should be utilized for patients who have voice complaints; that is, a strobe light source should be used to provide a composite picture and ultimately capture visible vocal fold vibration. This will inform aspects of vibration and function, such as glottic closure, mucosal wave, and vocal fold amplitude.

Fig. 4: Image obtained with PENTAX Medical laryngeal stroboscopy system. With high magnification, differences in color and pliability are much more easily visualized

Professional voice users may be more attuned to subtle changes in their voice resulting in vocal fatigue or slight dysphonia and could be a result of slight asymmetry or reduced vocal fold pliability that is not visible on laryngoscopy. Casiano et al. reported that 14% of patients had an altered diagnosis and treatment outcome after undergoing videolaryngostroboscopy.37 In 2015, Cohen et al. reported that 50% of patients who underwent videolaryngostroboscopy had a change in laryngeal diagnosis and treatment.38 These significant changes in initial diagnoses and ultimate treatment regimens further demonstrate the necessity of using a strobe light with laryngoscopy when evaluating and diagnosing professional voice users.

Examples of Vocal Fold Pathologies and Disorders

Several common pathologies seen in professional voice users will be reviewed here. A common inciting event that causes professional voice users to seek medical attention is often due to a prior upper respiratory infection (URI). It is important to consider the severity of the URI, the associated symptoms (e.g., coughing, sneezing, etc.), and the vocal demands of the professional both since the onset and moving forward.

Laryngitis is a common term used generally to describe voice changes that are often accompanied by a short-lived sore throat or cough. Laryngitis refers to general edema of the epithelium and/or the superficial layer of the lamina propria of the vocal folds and sometimes the surrounding structures (Fig. 5). Professional voice users who use their voice extensively often complain of episodic laryngitis, referring to periods of time where they experience voice changes and may have a sensation of soreness or inflammation in the throat, but this may not be an official diagnosis.

Fig. 5: Chronic laryngitis

Significant coughing and/or high vocal load during a URI, which often happens with professional voice users, may result in an increased risk for vocal fold hemorrhage, especially if the patient has been using non-steroidal anti-inflammatory drugs (NSAIDs). Vocal fold hemorrhage results from bleeding from the extensive and delicate blood vessels along the vocal folds, and often affects the superficial layer of the lamina propria (Fig. 6). Patients who experience vocal fold hemorrhage often report a period of complete aphonia, which is usually indicative of this type of pathology. On examination, vocal fold hemorrhage may appear bright red, indicating a present bleed, or patchy redness or yellow coloration with prominent blood vessels, indicating a resolving hemorrhage (Fig. 7).

Fig. 6: Vocal fold hemorrhage

Fig. 7: Prominent varices with evidence of recent hemorrhage

Vocal fold polyps may occur independently or in conjunction with a vocal fold hemorrhage. Polyps typically originate in the superficial layer of the lamina propria and occur at the midpoint of the vocal fold, which receives the highest impact during vocal fold vibration. They generally result from acute vocal trauma or ongoing phonotraumatic behaviors; due to the need to use or even project the voice extensively, professional voice users are at higher risk of developing these lesions. With a vocal fold hemorrhage, the blood from the initial bleed may collect at the medial edge and form a polyp (Fig. 8).

Fig. 8: Vocal fold polyp

Similar to vocal fold polyps, vocal fold nodules are benign vocal fold lesions that result from phonotraumatic behaviors. These are common lesions for professional voice users, including singers, actors, teachers, clergy, and salespeople. These lesions most often occur bilaterally at the midpoint of the vocal folds and also originate in the superficial layer of the lamina propria (Fig. 9). Vocal fold nodules can be either acute or chronic in nature, with acute nodules softer and more gelatinous and chronic nodules firmer and more like a callous.

Fig. 9: Vocal fold nodules

Vocal fold cysts are structural lesions that can sometimes be mistaken for nodules or polyps. These lesions are filled with mucous or fluid and are unique because the fluid/mucous is surrounded by its own membrane or sac. Similar to polyps and nodules, cysts are commonly found at the midmembranous portion of the vocal fold at the level of the superficial layer of the lamina propria (Fig. 10). These lesions can result from phonotraumatic behaviors, but they may also be due to a blockage in a mucus gland.

Fig. 10: Large submucosal cyst of the left vocal fold

Aside from structural vocal pathologies, disorders that are functional in nature are common in professional voice users. The most common functional voice disorder in professional voice users is muscle tension dysphonia (Fig. 11). On examination, professional voice users may have an absence of a structural change of the larynx but may continue to complain of hoarseness, vocal fatigue, throat pain, or other related symptoms. Interestingly, in a chart review conducted by Altman et al., of 150 participants diagnosed with muscle tension dysphonia, 63% reported excessive amounts of occupational voice use, 23% reported excessive loudness required in their profession, and 19% reported significant stress in their everyday life.39 These demands are very common in professional voice users seeking treatment; it is unclear the origin of most stress, but anecdotally, patients often report subjective stress due to their voice difficulty and not being able to do their job. Because of this, the question is whether there was stress that resulted in voice difficulty or if the voice difficulty is causing undue stress.

Fig. 11: Vocal fold abduction (left) and adduction (right) demonstrating pronounced supraglottic muscle hyperfunction characteristic of muscle tension dysphonia

Visual assessment of muscle tension dysphonia is not consistent between patients and may manifest differently depending on voice demands and degree of vocal fatigue during the evaluation. Izadi and Salehi reported a presence of lateral contraction for patients with an elevated larynx, while there was mild anteroposterior contraction for patients with a depressed larynx.40 Lee and Son also described a severe degree of anteroposterior contraction, false vocal fold approximation, decreased mucosal wave and vibratory amplitude, as well as a case of psychogenic vocal fold bowing.41 With increased intrinsic muscle tension, there may also be evidence of glottic gaps ranging from small slit gaps anteriorly to incomplete closure along the length of the membranous folds.42 The presence of a glottic gap may provide some confusion on evaluation, so it would be prudent to include a series of tasks during the examination, including reflexive tasks (e.g., throat clearing and coughing) and stimulability tasks (e.g., humming or gentle phonation) to determine if the glottic gap may be due to tension or a structural abnormality.

Voice Rest and Other Traditional Treatments

Voice rest as a treatment technique is usually only considered useful in acute pathologies, such as vocal fold hemorrhage or acute laryngitis, where avoidance of phonotrauma is critically important to resolving the underlying pathology. For chronic conditions, voice rest is not generally considered to be beneficial, as it does not change any voice use behaviors, though it can sometimes be useful to improve visualization of phonotraumatic lesions when significant edema is present. When treating professional voice users, discussion of voice rest may be challenging, particularly if it means requesting sick leave from work or canceling performances. Education and open communication is crucial in these cases so that the patient may understand the possible repercussions, such as continued hemorrhaging, additional phonotraumatic lesions, and permanent, irreversible scarring if they choose not to follow recommendations.

Many professional voice users inquire about the use of corticosteroids to facilitate return to work or performance due to their anti-inflammatory effect and reduction in glottic edema and stiffness. While this line of treatment may work for a short period of time, it again does not address the underlying pathology or behavioral issue. Steroid treatment also risks further vocal fold injury if the patient uses their voice at full power while temporarily feeling better. It is our recommendation to patients that steroids only be used if there are specific, unavoidable events that require voice use (e.g., a performance, a public speech, or an audition).

Some centers have treated dysphonic performers with empiric doses of antibiotics or vitamin B12, and there have been patients who reported benefit. However, antibiotic treatment is clearly not warranted for dysphonia without clear evidence of a bacterial infection, as most cases of acute laryngitis are viral in nature. A recent randomized control trial found no significant difference in the effect of vitamin B12 vs placebo in the treatment of performers, and this practice is generally discouraged.43

Management and Treatment

The management and treatment of voice disorders may depend on several factors: access to speech pathologists comfortable with treating voice disorders, access to appropriate medical and surgical equipment, the patient’s wishes, and the provider’s overall comfort with treating these disorders. However, it is critical to know that, unlike other ENT patients, voice patients generally require a multidisciplinary approach. Voice therapy provided by a licensed speech pathologist (preferably with some training in or experience with voice disorders) is often offered as the primary treatment modality but can also be offered in conjunction with medical or surgical treatment to avoid recurrence, or even to aid in the diagnosis.44 Misono et al. reported that 42% of dysphonic patients were referred to SLPs, 34% for therapy, and 8% for stroboscopy, emphasizing the crucial role of voice therapy as a treatment modality for dysphonic patients.45 Of note, the aforementioned study was not restricted to only professional voice users, so it is likely that the voice therapy referral rate may increase when considering only professional voice users.

Voice therapy has been shown to be effective in patients with muscle tension dysphonia46 and phonotraumatic benign vocal fold lesions, including nodules, polyps, and cysts.47-49 Therapy is often considered the “first line of defense” with functional disorders and benign vocal fold lesions.

Voice therapy can employ both indirect and direct approaches. Indirect approaches and strategies may focus on improving vocal health and hygiene as either a preventative measure or to decrease the severity of present symptoms. Counseling and education are often beneficial for professional voice users who feel as though their dysphonia or hoarseness is part of their job.50 Portable voice amplification is a common recommendation for professional voice users, particularly teachers. Gaskill et al. reported that the use of personal amplifiers reduced vocal fatigue and dysphonia in female kindergarten and primary school teachers.51

Direct approaches and exercises are generally necessary for professional voice users. These may focus on decreased compensatory muscle tension and improved coordination between respiratory and phonatory systems, especially if there is a need to project the voice or use the voice extensively daily. The intent behind these exercises is to ultimately reduce the impact on the vocal fold mucosa to decrease phonotrauma and avoid future or recurrent disorders. Patients with muscle tension dysphonia are generally recommended to complete a course of voice therapy because there are no structural abnormalities that can be managed surgically.

Management and treatment for structural pathologies may differ; depending on the size and location of benign vocal fold lesions (i.e., nodules, polyps, and cysts), other medical and/or surgical intervention may be necessary. Regarding vocal fold nodules, Johns reported that there is no evidence to support surgical intervention as an initial intervention for vocal fold nodules based on a literature review.52 Rosen et al. determined that all patients with vocal fold nodules responded to non-surgical treatment, thus there was no need for surgical intervention.53 However, it has been our experience that a subset of fibrous nodules may not fully respond to therapy and conservative treatment, and in some cases, intracordal steroid injections can be beneficial to reduce the stiff, inflammatory aspect of the lesions. In rare cases, surgical excision is warranted, but this is usually limited to more exophytic, pedunculated lesions.

Regarding vocal fold polyps, voice therapy is generally offered as a conservative approach to determine if the patient can reach sufficient vocal function. Depending on patient wishes and the voice demands of the specific professional voice user, it may be necessary to offer more invasive surgical options for voice improvement. Surgical intervention may occur with the use of an angiolytic laser, such as the 532-nm potassium titanyl phosphate (KTP) laser or a newer 445-nm blue diode laser. These lasers can be especially helpful in the management of increased vascularity and vascular lesions due to their wavelengths being preferentially absorbed by oxyhemoglobin. As a result, many vascular lesions can be removed in the office with much less energy and less resulting damage to the surrounding tissues. Some larger vocal fold polyps, particularly those with a significant endophytic component, may benefit from the stability and precision granted in the operating room when the patient is under general anesthesia.

Vocal fold cysts generally require surgery as the main course of treatment due to their high probability of recurrence after simple drainage or incomplete excision. These lesions do not usually respond to voice therapy as they typically are not reabsorbed as can be seen with a small polyp. Treatment for vocal fold cysts requires delicate microflap surgery utilizing an operative microscope and microlaryngeal dissection instruments (Fig. 12). Fortunately, this type of surgery is completely endoscopic and does not require any external incisions.

Fig. 12: Surgical removal of right vocal fold cyst

SUMMARY

Professional voice users are frequently seen in otolaryngology clinics due to the essential role their voices play in carrying out their work. These patients are at higher than average risk for developing voice difficulty because they are asked to use their voice often to its limit, thus resulting in phonotraumatic lesions and chronic, long-term changes to the glottic tissue. If/when professional voice users are forced to seek medical attention for voice-related complaints, providers must be knowledgeable in the appropriate areas of assessment and should continue education in differentiating various vocal fold lesions to ensure appropriate diagnosis and treatment. If the necessary equipment is not available, one should establish a voice care team in the area that can assist when these patients are in need. While voice disorders may not be the most common diagnosis, it is the job of medical providers to be prepared to provide the best medical care to these patients.

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