Patients who use their voices professionally should be treated with knowledge and skills that cannot be obtained only in the field of otolaryngology. It is part of the art performance discipline. The otolaryngologist uses the skills of the speech pathologist and the singing voice researcher to retrain and rehabilitate the patient’s voice. Teamwork is very important. The opening of various multidisciplinary sound centers in the last 10 years has shown the importance of teamwork.
Professional voice patients are a separate group. If the definition is limited to singers and actors, it will be taken too narrowly. Any person whose profession depends on the ability to speak and sing (salesman, desk clerk, telephone operator, lawyer, preacher, clerk, teacher, politician, public speaker, and doctor) should be considered a professional voice user because all of these people are significantly dependent on their voice.
It is singers and actors who need the vocal apparatus the most. The extreme practical and performance stress in these people is higher than in any other occupational group. They are generally well-trained and use their voices to their limits. No other patient group is as sensitive to changes in their voices as this group. Actors and singers with voice disorders are difficult cases for even the most experienced otolaryngologists.
ANATOMICAL ASSESSMENTS
Sound is a very sensitive marker of emotional state and general health. During the evaluation of a voice professional with a voice disorder, the whole body and psychological state should be evaluated together. The body itself is a vocal instrument, the larynx is the most important part of this instrument. Decreased function in almost any part of the audio professional’s body can lead to voice changes. Therefore, the larynx should not be considered as isolated.
A sound source, a vibrator and a resonator are needed for any type of sound reproduction. The lungs are the power source, the larynx is the vibration source, and the supraglottic vocal tract (supraglottal pharynx, oral cavity, and potential nasal cavity) is the resonator that converts sound into words and song. Sound is affected by a change in any of these three systems, which must be treated as a single unit in the assessment of the sound professional patient.
Laryngeal function is dependent on external and internal laryngeal muscles. The external laryngeal muscles change the position of the larynx. Classically trained singers use external muscles to stabilize the larynx in the neck while singing. 92 The internal larynx muscles provide precise control of the adduction, abduction and tension of the vocal cords.
Within the larynx, the human vocal cords are unique structures not found in any of the other animal species. Hirano et al.46,47 have described the trunk-cover theory for vocal cord vibration, which helps us to understand the laminar structure of the human vocal cord. The vocal cords are covered by stratified squamous epithelium. Subepithelial tissue, lamina propria is divided into superficial, middle and deep layers. The superficial layer contains protein-producing fibroblasts for the extracellular matrix of loose connective tissue and is often called Reinke’s space. It is composed of elastic fibers in the middle layer, and collagen fibers as primaries in the deep layer. Collagen fibers in the deep layer enter the thyroarytenoid muscle layer, which forms the main mass of the underlying vocal cord.
In the body-coverage theory of vocal cord vibration, the cover is composed of the superficial layer of the lamina propria and the overlying epithelium. The middle and deep layer of the lamina propria, known as the vocal ligament, forms a transition zone, and the trunk is primarily composed of the thyroarytenoid muscle. The contrasting masses and physical features of the vocal cord cover and trunk move at varying rates as air passes through the vocal cords. This movement, or vibration, strikes air, creating sound. This buzz-like sound is modulated by the supraglottic vocal tract and transformed into voice and song.
Blood vessels enter the vocal cords anteriorly and posteriorly. The veins run parallel to the longitudinal axis of the cord. This arrangement allows the drape to vibrate on the body without creating excessive tension and tearing force on the vessels. Various arteriovenous shunts have been demonstrated in the vocal cord microcirculation by electron microscopy. These are thought to allow autoregulation of blood flow to this region. 69 Gray et al41 began to reveal the basement membrane region and contents of the lamina propria. The basement membrane region is a complex region that attaches the epidermis to the superficial layer of the lamina propria. This is where the excessive tension force that occurs during vocal cord vibration occurs. Excessive tensile force can lead to disruption and infiltration of the basement membrane region. 40 This event is important in nodule formation. Type 3 and type 7 collagen fibers intersect in the superficial layer of the lamina propria. This arrangement fixes the basement membrane region to the superficial layer of the lamina propria, but also allows for passive tension during vibration.
Immunohistochemical analysis was used to investigate the basement membrane region and the extracellular matrix of the lamina propria. In diseased conditions such as a vocal cord nodule, the basement membrane region enlarges significantly. It was observed that collagen type 4 was lower in lesions diagnosed as polyps clinically than in healthy conditions. This relative weakness may have predisposed the formation of polyps.24,39
SOUND GENERATION
Vocalization starts with air or power supply. By sending a stream of air to the larynx (oscillator), the lungs provide the energy necessary for sound production. The diaphragm, intercostal, back, and abdominal muscles, and elastic springing of the chest wall work together to control the release of air.50,51 Classically trained singers use the abdominal and thoracic muscles to exhale; they use a greater proportion of their total lung capacity than singers without classical training to reproduce sound more effectively. 37,38 Efficient pushing of air into the larynx is the main difference between trained and untrained vocalists.
As the diaphragm relaxes and the chest wall is at rest, air is forced into the almost completely closed vocal cords. Compared to the width of the air passage of the trachea and subglottis, the pressure in the glottis region decreases as the speed of the air column increases, as a result of the decrease in the width of the air passage at the glottic level. This vacuum, which is created as a result of the decrease in pressure, brings the flexible tissue in the rima glottis, which is the membranous part of the vocal cord, closer to each other. Increased subglottal air pressure allows the cords to open. The vocal cords or rima glottal tissues open from inferior to superior (inferior to superior lip), forming a glottal configuration that converges and separates. In particular, the aerodynamic forces in the air column on the vocal fold cover and the myoelastic properties of the vocal folds are responsible for the repetitive opening and closing of the rima glottal tissue, which pushes the air column as air exits the glottis. Disruption of the continuity of tracheal air pressure by glottal activity causes sound production. The sound produced by the vibration source is of a buzzing quality. In professional voice production, glottal voice formation can be complicated by voluntary muscle activity, which can affect the intensity and frequency character of the glottal voice before the voice reaches the supraglottal tract.
The intensity of the sound source is directly related to the subglottic pressure. That is, the higher the subglottal pressure, the higher the sound intensity. People can change voice intensity by two methods using subglottal pressure. The first and possibly the most effective method is to modify the force of the air coming out of the trachea. This is achieved by increasing the air intake by activation of the abdominal and thoracic muscles and then controlling the outflow of air, partly by the thoracic cage elastic helix properties and partly by voluntary muscle activity. Regional classical schools of classical singing emphasize muscle control in different regions to achieve this phenomenon. However, this effect is the same as when the percentage of air used in singing is increased. The second method used to control subglottal pressure is the modification of the force used in vocal fold adduction. This method is less efficient. By increasing the thyroarytenoid (TA), lateral cricoarytenoid (LKA) and interarytenoid muscle activity, a greater resistance to glottal opening is obtained by increasing the laryngeal closure force. This, in turn, increases the subglottal pressure, increasing voice intensity. However, the vocal cord vibration frequency is directly dependent on the tension in the vibration system. Therefore, if the sound intensity is controlled by adding voltage to the vibration system, the frequency of the vibration may be unintentionally affected.
Well-trained vocal professionals can independently change the characteristic frequency of the source signal from vocal fold vibration to voluntary behavior. This is mediated by adjustments in cricothyroid (KT), TA, LKA, and IA muscle activity. When the KT muscle is activated, it lengthens the vocal cord, stretches the veil, and raises the frequency of vibration. Fine control of the degree of tension is achieved by balancing KT muscle contraction with TA, LKA, and IA muscle forces, keeping the vocal folds in the appropriate position for phonation. Unopposed KT muscle contraction increases glottal muscle width, which negatively affects the vibration cycle. In addition, the fine control of this mechanism ensures a smooth transition of the singing voice with the definition of the singers to the chest and head voice zones. Inappropriate or unmet changes lead to what is perceived as sound shifts. For a classically trained singer, this may not be pleasant, but it can be used for stylistic effects in commercial songs. This technique “yodel” is probably the most accepted stylistic technique for producing the desired sound.
Sound source signals produced by vocal cord oscillation have a fundamental vibrational rate defined as the fundamental frequency. In addition, the oscillatory source produces a wide spectrum of harmonies. Each harmonic is an integer product of the fundamental frequency. Supraglottal vocal tract; amplifies or attenuates certain regions of the harmonic spectrum source, depending on its length, shape, and the length of the aperture at the distal end. The amplified harmonic frequencies are defined as formant regions, they shape the output that is transformed into speech sounds from the sound source perceived as vocal communication. There are four or five formant regions important in vocal sound production. The first two of these regions are primarily responsible for vocal determination, while the third, fourth, and fifth formant regions shape the sound, or provide the timbre. Vocal professionals, especially those with classical training, can influence the characteristic of the vocal tract to modulate or alter these formant regions. When the three to five formant regions are brought closer together by volitional changes in the characteristic of the vocal tract, they amplify each other, thus creating a cymbal tone called the singer formant. This formant region, at 2300 – 3200 cycles/second, is primarily sensed by the human auditory system above other frequencies, allowing the singer to be heard and understood above the voice of the orchestra and other instruments.88-90 Appropriate use of these principles offers the professional voice user better vocal efficiency, which radiative output with less physical effort. Again, by changing the vocal tract length with the activity of the abdominal, thoracic and cervical muscles; changing the shape of the pharynx, tongue, jaw, and lips and vocal tract; By changing the width of the distal opening primarily with the movements of the chin and lips, a trained vocal professional can modulate the formant regions of the generated voice, creating an aesthetic sound quality for the listener. The aim of vocal training, whether classical or commercial, is to create a sound that satisfies the singer aesthetically by controlling these vocal sub-systems.
LARYNGEAL STROBOSCOPY
Although first reported by Oertel70,71 in 1878, stroboscopic examination has become popular recently. Stroboscopy is necessary to view the vibratory patterns of the vocal folds, which are formed so rapidly that they cannot be seen by the unaided human eye. 80,82,83 According to Tablot’s law, the retina can only resolve five images/second. For this, images presented to the retina in less than 0.2 seconds (five images/second) are viewed as continuous and are combined by the ocular cortex to create movement. Even the lowest vibratory patterns cannot be seen unaided, as the vocal cords vibrate between 75 and 1000 cycles. During stroboscopy, the larynx is visualized with a xenon light source. The characteristic of xenon light is that it allows rapid bursts. In this context, the larynx can only be observed in a short time frame, at an interval of 1/1000 seconds. Sampled from various points of a wide variety of vibratory cycles, these short images, when combined, allow the slow motion of the laryngeal vibratory tissue to be followed. In the modern stroboscopic setup, laryngeal vibration is detected by a microphone and the rate of xenon light firing is controlled. If the rate of visual sampling of the laryngeal image is out of phase with the rate of vibration, the laryngeal tissue is viewed as it moves. If the sampling rate is in phase with the vibratory rate, the laryngeal tissue is viewed as motionless.
Stroboscopy allows the observation of vibratory movement of the vocal cords, which is not possible in constant light. As described earlier, this vibratory activity is essential for sound production. For this, using the stroboscope, the observer can watch how small lesions change the normal laryngeal vibratory pattern. The significance of this lesion can then be determined.
In addition to providing information regarding the vibratory status, it can be used for consultations and comparisons of examinations recorded in video format with previous examinations. This information increases the efficiency in the diagnosis of vocal problems. Ideally, every professional voice patient should have a basic laryngeal stroboscopy of the time that is in normal health and voice. Findings can be compared with vocal fold images in dysphonic conditions, and conclusions can be drawn on the effect of vibration patterns on the causes of dysphonia.
Recorded laryngeal stroboscopic examinations can monitor changes in glottal vibratory patterns over days, weeks, and years. This phenomenon is known as intermittent examination, and can be used to investigate the effects of behavioral, medical, and surgical interventions on the larynx. Changes in laryngeal stroboscopic findings can be demonstrated and video can be stored or printed in computer format.
For the interpretation of laryngeal stroboscopy, the image of the healthy larynx during phonation at various frequencies and intensities should be known. Having a regular format for interpretation allows for a more objective interpretation of this subjective test. Standardized checklists of laryngeal stroboscopy are available.13,46,49,83 Evaluation criteria include symmetry, amplitude, periodicity, mucosal wave propagation, and glottal closure. These vibratory characteristics are evaluated at a comfortable sound level and modal sound frequency. In professional voice patients, it is more beneficial to perform laryngeal stroboscopy at high and low frequencies and during soft phonation. This provides additional information including vibratory characteristics.
Symmetry means the vocal cords are identical, which are seen as mirror reflections of each other during glottal vibration. Changes in the mechanical properties of the vocal cords such as mass, tension, fluctuation of the superficial layer of the lamina propria or mucosa, or inflammation may alter the symmetry. Asymmetry causes dysphonia.
Vibration amplitude is the lateral movement of the middle membranous portion of the vocal cord during vibration. This corresponds to one-third to half the width of the normally seen cord. Again, the mass, tension, and fluctuation of the vocal fold change the amplitude.
The periodicity, or regularity of successful glottal cycles, is assured by synchronizing the stroboscopic light with frequency. This will ”rotate” the image. The perceived movement of the vocal cords indicates the degree of aperiodicity. Changes in the balance of the vocal cords and the lung cause aperiodic vibration. During a single phonation, vibratory cycles can shift from periodic to aperiodic. Therefore, the vibratory pattern is fully periodic, often periodic, often aperiodic, or fully aperiodic.94,100
Mucosal wave progression is visualized on the superior surface of the cord. This depends on vocal cord vibration intensity and frequency. Lesions that fill the superficial layer of the lamina propria, infiltrating or pushing the vocal ligament, limit or eliminate the mucosal wave. In contrast, the superficial portion of the superficial layer of the lamina propria or small or medium-sized lesions confined to the mucosa, albeit diminished or asymmetrical, generally allow for propagation of the wave. 26,85 Finally, large and exophytic lesions change the mucosal wave into glottal shape and they change by disrupting the glottal closure. The mucosal wave must be separated by a vertical phase difference, which is the time difference in closure of the lower and upper lips of the vocal folds.
Closure of the membranous glottis is vital for the efficiency of the larynx. While there is complete glottic closure in men, 70% of women normally have a small posterior opening. The type of closure can be full, short or long, small or large posterior opening, thin-to-length, elliptical, hourglass, or asymmetrical hourglass. Closing; mass lesion, scarring, muscular tension, and neurological abnormalities.
AUDIO ANALYSIS
There are several methods for measuring sound vibration and quantifying sound. No test is considered the gold standard for documentation of vocal cord function. Each test has obvious limitations. In addition, there is variation within and between patients in repeated testing. Therefore, in professional voice patients, perceptual analysis by the trained observer is the most useful predictor of successful intervention in patient satisfaction with voice. Most laryngologists consider objective and semi-objective voice analysis important, especially considering preoperative and postoperative voice documentation. There is no consensus on the optimal test and its performance, relative importance, and interpretation.
Acoustic Measurements
Acoustic analyzes are used to objectively document and compare preoperative and postoperative surgical outcomes. Acoustic measurements are fundamental frequency, perturbation or loop-to-loop variation in frequency and amplitude, maxi mal frequency range, and others. Comparing intermittent exams requires high quality microphones and a strictly standardized technique recording system and patient interrogation. Although there are a variety of computerized acoustic analysis systems, their utility for the average patient is limited. Acoustic measurements have limited reliability secondary to variation in patient effort. In addition, the validity of acoustic measurements designed to assess periodic vibration in dysphonic sounds is controversial, as dysphonia causes aperiodic vibration.
Spectrometer
The spectrometer provides visual information about vocal harmonics and peak time, intensity, and frequency. This shows the effect of resonance (formant structure) and articulation in laryngeal buzz. Spectral analysis can be useful in evaluating and comparing resonance changes and documenting vocal changes after surgical procedures on the pharynx. Some laryngologists may find it useful in singers and other professional voice patients.5,78
Electroglottography
Electroglottography is the measurement of the effectiveness of glottal closure by recording the contact time of the vocal cords graphically. It shows the vocal cord opening and closing rates that cannot be seen completely with stroboscopy. Electroglottography is performed by placing two low-voltage high-frequency electrodes on both sides of the patient’s neck. It measures the electrical impedance that changes with the closing and opening of the glottis. Some clinicians consider this measurement objective and reproducible. Electroglottography, when combined with laryngeal stroboscopy and other vocal measurements, can provide clinically useful information.6,64,68
Aerodynamic Measurements
Aerodynamic measurements are based on fluid mechanics of airflow and include measurement of airflow, volume, and pressure. Some are related to Ohm’s law (D = B/A, D is laryngeal resistance, B is subglottal pressure, and A is airflow).
The normal aerodynamic information is so extensive that making comparisons between patients is therefore pointless. However, changes in measurements are quite significant in the evaluation of changes in laryngeal closure in patients undergoing surgical intervention.
Standard lung function tests can be used to objectively evaluate the lungs. Moderate obstructive and restrictive lung diseases can be found on the basis of the patient’s vocal fatigue and dysphonia. Cough-variant asthma and other reactive airway diseases can be ruled out with bronchodilator trials and methacholine testing.
Subglottal pressure can be measured by indirect methods instead of techniques such as tracheal puncture and esophageal balloon. It is measured by oral pressure with the glottis open. For breathless final consonants such as /p/ and /t/, the oral pressure reaches equilibrium with the subglottic pressure across the open vocal cords.
The maximum phonation time is (1) the phonation length of the vowel /a/ at a comfortable frequency with one breath, and (2) the average of the sound after deep inspiration. Although highly variable, laryngeal competence and glottal closure can be reasonably predicted.
The mean airflow rate (airflow volume / phonation time) of a prolonged vowel /a/ is rarely tested. In general, low flow rates suggest laryngeal hyperfunction, obstruction, and primary lung disease. Increased values indicate abnormalities in glottal competence and cause air leakage.
Perceptual Analysis
The “trained” ear is the most distinctive instrument for evaluating professional voice.7,28,61 Perceptual improvement or worsening of professional voice is critical for the singer, manager, fellow singers, laryngologist, vocal speech pathologist, and vocalist. To make the perceptual analysis more objective, vocal characteristics can be systematically examined independently. Additionally, judges receive vocal evaluation training to reduce subjective bias. However, there is no universal consensus on the terminology of vocal characters. Hirano48 suggested the widely used GRBAS scale (grade, coarse, air leak, asthenic, forced). Despite this, Sundberg91 and Kreiman et al60 have conducted research in this area and concluded that the clinical application of perceptual analysis is difficult at this time.60,91
Audio Results
Due to diurnal variations in vocal measurements, vocal quality is often determined by patient satisfaction or by comparing the sound at different times. Patient satisfaction is assessed with direct questions or questionnaires specifically designed to rate perceived vocal problems. The sound can be directly compared with recorded samples. Blind analysis of voice changes can be performed, eliminating day and other distinguishing factors. A community of decision makers may blindly evaluate objective qualitative changes over time. This is how the effect of a particular therapeutic intervention can be evaluated.
Outcome studies have become a valuable tool for studying most diseases. A voice handicap index was developed to assess the patient’s perception of voice and his response to treatment.12 This research method should prove valuable in the evaluation of professional voice patients.
EVALUATION
Medical History
A complete history of current illness and previous medical problems is required. Various otolaryngologists are developing patient questionnaires to get the broadest medical history and speed up the evaluation process.77
The most striking points in the patient’s medical history and general health are diseases that affect the lungs, posture and hydration. Any acute or chronic condition affecting the lungs significantly affects the singer’s voice. Diseases that impair lung function, such as asthma, emphysema, or chronic bronchitis, reduce the power of the source that powers the singer’s voice. Musculoskeletal injuries alter posture and impede the neck’s ability to position the patient’s larynx, resulting in vocal dysfunction. Prescription and over-the-counter drugs change the voice through their effects on the autonomic nervous system and their indirect effects on the larynx and vocal tract.55,93 Drugs that affect the patient’s mood change the patient’s approach to vocal function. The drug reduces laryngeal lubrication by causing dehydration, which in turn affects vocal cord vibration. In women, the use of oral contraceptives and hormonal drugs (eg, danazol) that may adversely affect the voice should be included in the history.14,84,98
Personal habits of the singer should be noted. Frequent alcohol use or alcohol addiction causes dehydration, affecting the voice and impairing the decision-making mechanism. Caffeine (a diuretic) and high-fat dairy products act by thickening mucus secretions and reducing the effectiveness of vibration. Some foods and alcohol increase gastroesophageal reflux.55 Finally, tobacco use should be questioned. Inhaled cigarette smoke acutely irritates the mucosa and increases reflux, which means it will reduce vibratory efficiency. In addition, smoking leads to neoplastic change.
Past surgical history is important in patients with laryngeal dysfunction. In addition to head and neck procedures, the history of endotracheal intubation should be questioned as the larynx may be affected. Recent abdominal or thoracic surgery may limit the singer’s inspiratory and expiratory capacity for weeks and months after surgery.
It is also helpful in revealing endocrine disorders. Laryngeal manifestations of hypothyroidism can cause dramatic edema in the Reinke’s space.44 Even mild hypothyroidism makes the voice difficult to understand, causes pitch reduction and vocal fatigue.
Voice changes caused by hormonal fluctuations just before and after menstruation are less well understood. Flach et al.34 reported that 75% of female singers had premenstrual changes such as decreased pitch and vocal fatigue. Using cytological swabs, Abitbol et al.2 objectively demonstrated cyclical changes in vocal cord epithelial cells to coincide with menstruation. This has been described as laryngopthia praemenstrualis.63 Vocal cord varices increase in size before and after menstruation and are related to submucosal vocal cord hemorrhage.22,79 Vocal cord varices are frequently found in female professional voice patients. 1,22,67,73
The history taken should also include what kind of education the singer received. Does the patient currently have a vocal trainer, or has she just changed the trainer? What are the patient’s long-term goals? A trained vocalist can correct their vocal technique more quickly than an untrained one.
History of Current Disease
The nature of the singer’s complaint should be carefully reviewed. The vocal professional may simply complain of roughness in the voice. It describes a wide variety of vocal abnormalities, including vocalization, (often) loss of the upper pitch, scratchy voice, pitch (frequency) irregularity, difficulty transitioning between song pitches, and early vocal fatigue. These are often symptoms of laryngeal edema, muscle tension dysphonia, extraesophageal reflux, upper respiratory tract infections, nonneoplastic lesions, or poor vocal technique. For this, the patient should be specifically questioned in terms of vocal range, frequency interruptions, anterior cervical discomfort, esophageal reflux, and mental and physical strength. The beginning and end of vocal strain often provide clues as to why. It is important to reveal the cause of the relationship between the time of day of the difficulty, the situations that aggravate the dysphonia, the events just before the difficulty, the dysphonia and the use of voice, and may be useful in treatment.
Air travel, performing on old stages, contact with chemicals and fumes, and having a very full schedule are professional activities that can cause these problems. Air travel is a problem for the sound user because the air in airplanes is very dry (5-10% relative humidity) and affects the larynx; background noise causes the patient to speak louder.32 Performing in old scenes that may be dusty, walking around areas where allergens are concentrated may cause distortions in the patient’s voice. Exposure to various irritants, including cigarette smoke, at parties or performance in cigarette smoke-filled venues can affect the sound. Vocal sound professionals who are interviewed very often can develop varying degrees of dysphonia. The singer’s schedule can make it difficult for her to drink large amounts of water for vocal cord lubrication, and although the singer mainly complains of the problem in singing, the main difficulty is vocal abuse due to excessive speech. Significant abuse of speech voice leads to marked difficulty in singing.
Often, a young vocal professional seeks help when the problem becomes apparent, or when he’s going on tour or performing in the near future. The type of treatment depends on when the next performance will be. This should be considered when preparing a treatment plan.
Physical Examination
A full head and neck examination should be performed for every voice patient who goes to an otolaryngologist or laryngologist. The vocal professional’s physical assessment begins with an assessment of the patient’s walking and posture when he enters the doctor’s office. Can the patient comfortably stand back on the shoulder or with the shoulder relaxed? Is the patient tense or irritable?
While taking a history, the doctor should also evaluate the patient’s speech voice. The sound frequency should be appropriate for the patient’s age, gender and body habits. The volume should be suitable for the speaking voice. It should be studied including the beginning of the sound, the breaks in the sound and the whole rhythm. Finally, vocal quality should be evaluated in terms of coarse voice, breathless voice, asthenia and constriction.
Examination of certain areas outside the larynx is key. The range of motion of the jaw should be checked, and the temporomandibular joint should be palpated. Temporomandibular joint dysfunction can create significant muscle tension difficulties in professional voice patients. Laryngeal hyperfunction can cause tenderness in the anterior neck or cervical paraspinal muscles.
The ears should be examined for an abnormality and an audiogram should be requested. Hearing loss, especially sensorineural hearing loss, can cause the singer to sing loudly, resulting in extreme trauma to the vocal cords.
Nasal examination can provide information about mucosal membrane disease. Pale and edematous nasal mucosa indicates the presence of pronounced allergy. Presence of chronic infection or crusting with purulent discharge should be noted. Nasal obstruction leads to chronic mouth breathing. As a result, contact of the larynx with unfiltered dry air thickens the secretions, leading to marked dysphonia, which raises the phonation threshold pressure. In addition, the nature of the patient’s secretions can be determined by noting their continuity in the nasal and oral cavity. Cough caused by chronic postnasal drip may cause vocal cord edema.
There are three ways to examine the larynx: laryngeal mirror, rigid telescope, or flexible fiberoptic laryngoscope. The first and classical method is the laryngeal mirror. This examination gives the most natural color and potentially gives a panoramic view of the larynx. This method is most satisfactory in identifying old vocal cord hemorrhage.
Vocal professionals are evaluated with a rigid telescope and a flexible fiberoptic laryngoscope. Single-point light sources may discolor, and this should be considered when evaluating the larynx. rigid indirect endoscopy and flexible laryngoscopy are complementary; each has definite advantages. Using both methods, the laryngologist can fully evaluate the professional voice patient. The use of a rigid telescope requires the physician to gently hold the patient’s tongue and pull it forward. This maneuver alters the normal use of the patient’s supraglottal tract and articulators, making interpretation of glottal closure and laryngeal hyperfunction difficult. But the telescope offers the best illumination, gives a non-parallel view of the larynx and allows for photodocumentation. Small lesions or areas of vascular abnormalities in the larynx can be missed with a laryngeal mirror or flexible fiberoptic laryngoscope, which can be seen with a 70- or 90-degree telescope. In addition, laryngostroboscopy is more optimally performed with a rigid telescope compared to a flexible instrument. The picture is cleaner, larger and clearer, allowing the doctor to better assess the laryngeal vibratory pattern.
The flexible fiberoptic laryngoscope allows the vocal professional to examine more naturally. The patient can speak or sing during examination of the supraglottic tract and larynx. This provides a better evaluation of vocal biomechanics, especially in laryngeal hyperfunction. Finally, patients who cannot tolerate the rigid telescope due to anatomical variant or excessive gag reflex are better tolerated by flexible fiberoptic. The disadvantages of the optical system are the well-known fisheye distortion of the peripheral image, reduced resolution, linear color line distortion (moire effect) in the video image, and reduced illumination, which complicates the interpretation of stroboscopy. 17 These problems can be resolved by using a flexible endoscope with a distal chip camera.
Large mucosal lesions or vocal cord paralysis may be very apparent to the examiner. Definite, sometimes vague, laryngeal findings may be less pronounced. Thick sticky mucus secretions should be noted and compared to the generally seen and more preferred aqueous lubrication. Vocal cord edema, ventricular effacement and erythema, granulation tissue in the posterior glottis may indicate extraesophageal reflux. Vocal cord edema, especially in the middle 1/3 of the vocal cord, can be found in vocal professionals with mild dysphonia complaints. Hyperfunction findings should be questioned. In its most ambiguous form, this may manifest as enlargement of the posterior glottis. In worse hyperfunction, closure of the false vocal cords (plica ventricularis) may be seen, as well as anterior to posterior contraction of the supraglottis. If these are present, occult vocal fold paresis should be considered.
If the cause of dysphonia is not revealed by examination, the vocalist should also be examined by a vocal pedagogue. The posture and general posture of the singer should be noted. The ‘singer stance’ is a standing position with the feet shoulder-width apart and the weight slightly in front of the heels. Often commercial singers play instruments while singing. In this case, the patient should be examined while holding the instrument. If facial, shoulder, or cervical tension is present while the patient is singing, it should be noted. Does the singer use the abdominal muscles appropriately to support her voice, or does she use her breathing only with the help of the rib cage and shoulders? It should be noted whether there is laryngeal elevation with the increase in frequency. This qualifies as poor technique in the classically trained singer and can cause vocal fatigue due to excessive muscle tension. In commercial singing, laryngeal elevation is often used to achieve the desired sound, and loss of elevation results in uncharacteristic vocal quality.
PROBLEMS IN SINGERS
Professional voice patients have the same diseases that affect the general population. However, due to their great need for their voices, they are extremely susceptible to problems involving the larynx and areas of voice production.
Extraesophageal reflux
Gastroesophageal reflux is a common problem that usually presents with complaints such as heartburn, gas in the stomach, or an acidic taste in the mouth in the morning. Patients may have significant reflux without abdominal or chest complaints, this is called extraesophageal or laryngopharyngeal reflux. 36,45,55,59,72,74 Frequent throat clearing, moderate dysphonia, phlegm sensation or foreign body sensation in the throat (globus), vocal fatigue, cervical dysphagia, or decreased pitch are symptoms.8,10 Singers and other vocal professionals with extraesophageal reflux experience coarser voices in the morning and require a longer warm-up. Reflux laryngitis should be questioned during physical examination.9,11 If symptoms and signs suggest extraesophageal reflux, conservative treatment with diet and general lifestyle is initiated. It is difficult for singers with very busy schedules to comply with these measures. Extraesophageal reflux is best controlled with a proton pump inhibitor. It is used half an hour or an hour before a meal and twice a day for extraesophageal reflux. It is unclear whether drugs that increase gastric emptying are beneficial in the treatment of extraesophageal reflux. 24-hour pH monitoring is applied to patients with a mixed clinical picture or who do not respond to maximal dose proton pump inhibitors. Some patients may be resistant to omeprazole.4,15,53,65
Laryngeal Hygiene
Laryngeal hygiene can be problematic in professional singers. The key to good laryngeal hygiene is adequate hydration. Poor hydration leads to a decrease in mucous viscosity, leading to decreased effectiveness of vocal cord vibration.33,95,96 Singers have to drink large amounts of water. Van Lawrence stated that singers should drink water until their urine turns pale, vocal professionals should let their kidneys tell how much water they should drink, not a specific amount. The daily water requirement is considered to be at least eight glasses, and the amount drunk should be increased if the voice user is airborne, sick, or has an overloaded performance schedule. Since caffeine has a diuretic effect, its use should not be supported. Dairy products also appear to increase the viscosity of secretions and inhibit the healthy smooth vibratory functions of the vocal cords. Guaifenesin may thin secretions in some patients. Tobacco use in the professional voice patient also leads to poor laryngeal hygiene.
Vocal Abuse and Abuse
Vocal abuse describes vocal behaviors related to normal voice quality that lead to vocal cord abnormalities and subsequent dysphonia. These behaviors allow clear manifestations of abuse to be seen during the laryngeal examination. Vocal abuse occurs in two forms: the forms of abuse are present in the patient’s speaking or singing voice. Vocal abuse is characterized by forcing the voice step by step, primarily (1) excessive rehearsal (2) spending a lot of time in the studio (3) singing too loudly (4) singing outside of the singer’s possible limits. Additionally, in commercial songs, artificial coarse sound is often added to add ‘validity’ to the performance.
Vocal abusive behavior can occur if the singer over-interviews. Shouting and talking too much in areas with loud background noise (restaurants, aircraft) is common. Vocal professionals should protect their voice by restricting unnecessary speech, exercising what is called relative voice rest. This is especially important if the vocalist has vocal difficulties or is ill. Punt75 advises singers to ‘avoid unnecessary talk unless paid for’, especially if they are sick or have an extremely busy performance schedule.
Vocal abuse describes dysphonia that develops with abnormal functioning of anatomically normal structures. Chronic abuse ultimately leads to organic vocal fold changes. With this change, they manifest as vocal nodules, disrupting the normal laryngeal vibratory pattern and causing dysphonia. Cessation of inappropriate vocal behavior reduces or eliminates dysphonia. Over time, organic changes may return, and healthy vibratory patterns may return.
Muscular tension dysphonia is not limited to vocal professionals. It can be the cause of primary or secondary dysphonia. The singer is not immune to these, due to the misconception that vocal training will destroy it. This problem is frequently seen as a form of compensatory behavior, especially maladaptive, after an upper respiratory tract infection. While the vocal cords and pharynx are edematous, the singer tries to produce a normal voice and develops inappropriate vocal behavior. Patients usually complain of hoarseness, vocal fatigue, loss of pitch, and discomfort in the neck and ears.
Koufman and Blalock 54,58 formulated a classification and rating system for muscular tension dysphonia. Class 1 muscle tension dysphonia is defined as an enlarged posterior glottal opening, elevated larynx, and palpable neck tension and tenderness with increased muscle tension. This causes air leakage and/or a loud and irritating sound and is often seen in patients with vocal nodules. Class 2 muscle tension dysphonia is a lateral to medial construction of the larynx while the false vocal cords are abducted. This causes increased vocal fatigue. In its most extreme forms, false cords called plica ventricularis are used for phonation. It is usually seen as a compensatory maneuver after laryngitis or laryngeal surgery. Class 3 muscle tension dysphonia is anterior to posterior constriction of the supraglottis while the epiglottis and arytenoids cover 50% of the laryngeal adduct. Class 4 muscle tension dysphonia is present when the epiglottis and arytenoids are in contact with each other, and lateral contraction is usually seen.
Koufman56 studied laryngeal biomechanics while singing. A hundred singers with various singing styles were evaluated with fiberoptic laryngoscopy. Koufman found that vocal training, warming up before singing, and classical music styles reduce muscle tension. This study supports the belief that vocal training increases vocal efficiency and reduces muscle tension. Koufman found that asymptomatic singers with vocal nodules had significantly greater laryngeal muscle tension than those without nodules. Treatment of muscle tension dysphonia is guided by the voice speech pathologist and vocal pedagogue. It aims to increase the patient’s speech and singing efficiency by retraining, thereby reducing laryngeal tension and vocal cord trauma.
The interesting type of vocal abuse in professional voice patients is inappropriate low-frequency speech sound. This deepening of the voice gives it a more authoritative quality. Maintaining it requires significant muscle tension.57
Laryngitis
Acute laryngitis (inflammation of the laryngeal mucosa) is common in adults and can be very devastating for the professional voice patient. Inflammation of the vocal cords causes irritation and edema, and makes smooth movement of the mucosa difficult, resulting in dysphonia. To compensate for this and maintain their normal voice.
