Evaluation of voice disorders

voice disorders assessment

1. EVALUATION OF VOICE DISORDERS

2. FUNCTIONS OF LARYNX Protection of tracheobronchial tree Respiration Phonation To increase intrathoracic pressure ( effort closure ) Swallowing (deglutition) Coughing

3. Why VOICE matters ??? The moment we open our mouths we are judged . As words are spoken assumptions are made about who we are – presumptions about our intelligence , desires , determination , confidence and influence are all inferred from how we use our voices . Our voices are our strength , weapon , power . We have the ability to do great things with it . Our tone , pitch, quality of articulation and inflection deliver subtle messages about the kind of person we are . Its evident those with communication impairments are at a serious disadvantage .

4. How phonation occurs ??? INITIATION OF VOICE : Prephonatory inspiratory phase Vibrator – vocal folds Excitor - exhaled air Vocal fold oscillation Phonation threshold pressure

5. Subglottic air pressure increases below the adducted vocal folds until it reaches a level which overcomes their resistance and blows them apart, thus setting in motion the vibratory cycles which result in phonation .

6. VIBRATORY CYCLE 3 PHASES : ADDUCTION AERODYNAMIC SEPARATION RECOIL

7. As the increased subglottic pressure overcomes the resistance of the adducted vocal folds at the onset of phonation, the vocal folds peel apart from their inferior border. When they finally separate at their superior margin, a puff of air is released. The resulting negative pressure in the glottis, caused by the Bernoulli effect, results in the vocal folds closing rapidly as they are sucked together, the inferior vocal fold margins closing first.

8. The Bernouilli effect is a drop in pressure dependent on particle velocity. In relation to the vocal tract,when air passes from one large space to another (e.g. from lung to pharynx), through a constriction (the glottis), the velocity will be greatest and the pressure least at the site of the constriction. As a result of the drop in pressure at the glottis, the vocal fold mucosa is drawn into space between the vocal folds. Contact between the vocal folds increases until the subglottic air pressure is high enough to blow the vocal folds apart again, and the cycle recommences.

9. COVER/ BODY THEORY Each cycle of adduction, separation and recoil is the manifestation of a mucosal wave travelling from the inferior to the superior surface of each vocal fold. The process by which this undulating wave of movement of the mucous membrane occurs is dependent on what is known as the cover/body theory. Vocalis muscle provides the firm body of the vocal fold over which the mucous membrane cover of the vocal fold is blown by the expiratory air stream.

10. VOICE EVALUATION The voice is multidimensional, so voice assessment should be. PATIENT SCALES PERCEPTUAL EVALUATION MEASURES

11. PATIENT SCALES Voice is produced by interactions among the respiratory, laryngeal, and resonance systems The patient's perception of the problem is an important component of the evaluation. Several published scales can be used to report various aspects of handicap or quality of life . The speech-language pathologist's voice evaluation is multifactorial, assessing each system in addition to the speech output. A group of measures is frequently selected to capture the primary elements of the voice, such as pitch, loudness, and quality.

12. VOICE HANDICAP INDEX

13. PERCEPTUAL EVALUATION Auditory Perceptual Assessment Visual Perceptual Examination Tactile Perceptual Evaluation

14. Auditory Perceptual Assessment GRBAS is a well-known standard scale that was developed by the Committee for Phonatory Function of the Japanese Society of Logopedics and Phoniatrics . G represents grade or overall quality. The other four letters represent dimensions of voice quality, as follows : R for roughness, B for breathiness, A for asthenia, and S for strain. Each parameter is rated on a 4-point scale: 0 means that there is no deficit in this parameter, 1 is a mild deficit, 2 is a moderate deficit, and 3 indicates a severe deficit.

15. Parameter Hirano Definition National Center for Voice and Speech Definition Grade (G) Overall severity Roughness (R) Psychoacoustic impression of irregular vocal-fold vibration An uneven, bumpy quality that appears to be unsteady in the short term but stationary in the long term; acoustically, the waveform is often aperiodic, with the modes of vibration lacking synchrony, but voices with subharmonics can also be perceived as rough. Breathiness (B) Psychoacoustic impression of air leakage through the glottis Containing the sound of breathing (expiration) during phonation; acoustically, breathy voice, like falsetto, has most of its energy in the fundamental, but a significant component of noise is present owing to turbulence in the glottis. In hyperfunctional breathiness, air leakage may occur in various places along the glottis, whereas in normal voice, air leakage is usually at the vocal processes. Asthenia (A) Weakness or lack of power in the voice A voice that appears too low in effort, weak; hypofunction of laryngeal muscles is apparent. Strain (S) Psychoacoustic impression of a hyperfunctional state of phonation A voice that appears effortful; visually, hyperfunction of the neck muscles is apparent; the entire larynx seems compressed

16. Visual Perceptual Examination The visual perceptual examination refers to visible and physical aspects of voice production related to etiology , maintenance, or effect of dysphonia . Koschkee and Rammage have divided the visual perceptual examination into the following five categories: ( 1) general appearance ( 2) posture, breathing, and musculoskeletal tension ( 3) neurologic dysfunction (4 ) physical dysmorphology ( 5) clinical manifestations of disease

17. General appearance factors - apparent age, height and weight, facial expression, skin, hair, and nails, personal hygiene and dress, and head and neck observations, can be indicative of underlying systemic disease, previous treatment, or emotional disorder. One example is the masked face of parkinsonism . Posture, breathing, and musculoskeletal tension are key components of a voice evaluation because they frequently affect pitch, loudness, and quality. Postural assessment likely involves information about the alignment of the head, neck, torso, pelvis, and legs. Visual assessment of breathing includes observations of neck, shoulder, chest, and abdominal movement. Reports of musculoskeletal tension contain information about extent of jaw motion, chin jut, neck extension, bulging of the neck muscles while talking, or raised shoulders .

18. Neurologic dysfunction is indicated by observations such as unsteadiness, asymmetry, rigidity, hesitation, slowness, weakness, incoordination, inconsistency, and extraneous movements. Weakness , asymmetry, and incoordination of the tongue, jaw, lips, or soft palate are especially noteworthy. The presence of focal dystonias , such as writer's cramp, blepharospasm , torticollis, and oromandibular dysphonia, usually leads the examiner to consider a neurologically based voice disorder, such as spasmodic dysphonia.

19. Tactile Perceptual Evaluation The manual examination of laryngeal musculoskeletal tension includes palpation of the suprahyoid muscles, the major horns of the hyoid bone, the superior cornu and the lateral aspects of the thyroid cartilage, the thyrohyoid space, and the anterior border of the sternocleidomastoid muscle. It is useful to assess suprahyoid tension and thyrohyoid space both at rest and during phonation. The examiner should also attempt to move the thyroid cartilage from side to side. Some authors recommend palpating the thyrohyoid, cricothyroid, and pharyngolaryngeal (inferior constrictor and posterior cricoarytenoid ) muscles as well . Normal findings include palpable space between the hyoid bone and the superior border of the thyroid cartilage and mobility of the laryngeal complex. Findings indicative of excessive musculoskeletal tension include pain with palpation (frequently more severe on one side), decrease or absence of thyrohyoid space at rest or with phonation, muscle “knots,” high carriage of the hyoid bone and thyroid cartilage, and difficulty rotating the larynx.

20. A drawback of the examination is that it is subjective, and examiner's skill and experience likely affect ratings. In addition, there are currently no intra- or inter-examiner reliability data for the technique, and the sensitivity and specificity of abnormal findings are unknown. Even given these limitations, tactile perceptual evaluation is a powerful technique to rapidly assess the contribution of muscle tension to the observed voice quality. Teasing apart the muscle tension and other components of the dysphonia can help ensure proper diagnosis and management; the tactile examination is one tool used in this endeavor .

21. MEASURES Many different types of measurements can be used in the voice evaluation to describe pitch, loudness, and quality. Most speech-language pathologists use a subset of these measures, depending on their particular philosophy, education, and the equipment available to them . Chest wall displacement Aerodynamic assessment Acoustic analysis Vocal fold measures

22. CHEST WALL DISPLACEMENT : Measurements of chest wall movement can be used to estimate volume changes during voice production. Reports typically include information about the lung volumes used and chest wall shape during phonation . Lung volume variables of interest are the volumes at which the patient initiates and terminates speech . In general, people tend to initiate phonation around 20% of vital capacity above resting tidal end-expiratory level and to terminate phonation around resting tidal end-expiratory level. Shape is usually described in terms of rib cage wall and abdominal wall movement. Because some shapes are more mechanically advantageous to phonation, the patient's typical shape and ability to change shape might be reported .

23. AERODYNAMIC ASSESSMENT : Aerodynamic evaluation involves measuring air pressures and airflows.

24. Acoustic Analysis : The acoustic speech signal is the system's output and is rich in information about pitch, loudness, and quality. The signal is quite complex and is therefore broken down for analysis into the dimensions of frequency, amplitude (intensity), and time . Acoustic measurements are best made from signals recorded on high-quality equipment in a quiet environment and with the use of standard instructions. Data should be interpreted in light of subject age and gender, interactions between parameters, speech sample selected for analysis, and number of tokens. It is also important to know whether the samples were consistent with typical voice use or maximum/best performance

25. Measure Perceptual Correlate Frequency ( Fo ) Pitch Intensity (sound pressure level [SPL]) Loudness Voice range profile (VRP) Interaction of pitch and loudness ranges Variability measures Quality (e.g., roughness, breathiness, timbre) Spectral displays Quality Fast Fourier transform (FFT) Quality Linear predictive coding (LPC) Quality Long-term average spectrum (LTAS) Quality Cepstral peak prominence (CPP) Quality Nasalance Hypernasality , hyponasality

26. Measures of Vocal Fold Vibration ELECTROGLOTTOGRAPHY : Electroglottography (EGG) measures the conductance of a low-frequency electric signal across the neck between two surface electrodes . The conductance of the signal varies with the vibration of the vocal folds; when the vocal folds contact each other, conductance increases, and the resultant EGG trace has a positive slope. As vocal folds separate, conductance decreases, and the trace has a negative slope. Because the traces display the extent of contact relative to the rest of the signal, maximum contact does not necessarily indicate complete vocal fold closure. The waveform's shape is potentially meaningful for describing the pattern of vocal fold vibration.

27. In EGG, abnormalities in the signal are not always the result of abnormalities in vocal fold motion; the signal can be affected by the placement of electrodes, movement of the larynx during phonation, irregularities of neck tissue, and mucous bridges. Even given its limitations, EGG is an excellent measure of fundamental frequency and offers a unique opportunity to study the vocal fold vibration without any influence of supraglottic structures or shaping. It is noninvasive , relatively inexpensive, and can be used at the same time as other measures (e.g., airflow, videostroboscopy ).

28. INVERSE FILTERED FLOW : In inverse filtered flow, the effects of the vocal tract (resonances) are filtered out of either the acoustic or the aerodynamic waveform, and the glottic source signal is left. From this trace, several measures can be made, including skewing quotient (the ratio of the positive slope to the negative slope) and open quotient (the ratio of the time open to the period of the waveform ). Inverse filtered flow is quite useful because it allows us to study the glottal flow signal, yet it is technically complicated and therefore challenging to incorporate into clinical assessment protocols.

29. VISUALIZATION OF LARYNX ENDOSCOPES VIDEOENDOSCOPY and STROBOSCOPY HIGH DIGITAL IMAGING NARROW BAND IMAGING

30. ENDOSCOPES

31. RIGID ENDOSCOPES : ( Usually 70 or 90 degrees ) ADVANTAGES DISADVANTAGES High resolution with bright, clear pictures Contrast is excellent Large selection of viewing angles image is more accurately magnified than with a flexible endoscope. The examination is simple and does not usually require topical anesthesia . Phonation is limited to sustained vowels, most commonly “ ee .” Because visualization with a 70-degree rigid endoscope usually requires an extended neck and protruded tongue, the size of a glottic gap might appear exaggerated with the rigid endoscope. The mobility of the arytenoids might not be accurately assessed via rigid endoscopy; often, it appears as if there is a vocal fold paresis when the perceived lack of motion is, in actuality, an artifact of the tongue protrusion and neck extension. Disorders more evident in connected speech than in sustained vowels (e.g., muscle tension dysphonia and spasmodic dysphonia) are not as well documented with rigid endoscopy as they are with flexible endoscopy.

32. FLEXIBLE ENDOSCOPES : ADVANTAGES DISADVANTAGES The ability to view the larynx dynamically—that is, during natural functions such as speech and singing. Arytenoid mobility and the glottic gap can be more accurately described with flexible than with rigid endoscopy because of the neutral tongue and neck positions. Allows the clinician to assess the nasal cavity and velopharyngeal port during the same examination. Flexible endoscopy is preferred when the question is one of movement rather than structure or mucosal health. It is particularly useful for disorders such as spasmodic dysphonia and muscle tension dysphonia, in which the voice problem is more obvious during speech than in sustained vowels, and vocal fold motion impairment, where having the patient sniff through the nose allows the examiner to assess subtle motion. Light transport and magnification of the image are inferior to those of rigid endoscopy. There is also a distortion of the periphery of the image and a trade-off between adequate focus and light fiber mismatch, so that when the image is in focus, there is a moir ? or honeycomb effect that is enhanced by the edge-detection software of digital imaging systems. Although the chip-tip endoscope represents a significant improvement, the new technology comes at a significant cost increase, and the quality of resultant examinations is not equal to that achieved with rigid endoscopy. In addition, many patients find the flexible examination to be more invasive than the rigid examination, and the flexible technique carries the risks of nosebleed, adverse reactions to the anesthetic , and vasovagal reaction.

33. STROBOSCOPY A stroboscope is defined as “an instrument for determining the speed of cyclic motion (as rotation or vibration) that causes the motion to appear slowed or stopped .” Videostroboscopy is not slow-motion photography; it is an illusion of slow motion. The illusion is possible because images linger on the retina for 0.2 second, and only five distinct images can be viewed per second. If more than five per second are presented, the viewer perceives the images as connected and sees the result as a smooth motion; this phenomenon is referred to as Talbot's law . For videostroboscopy to be used for the analysis of vocal fold vibration, the light must flash at specific points in the glottic cycle, or the illusion of slow motion vibration will crumble. Extraction of the vocal fold fundamental frequency (rate of vibration) facilitates the process.

34. The strobe light can be used to create two effects, the running phase (often called strobe) and the stop or locked phase . In the running phase (the more frequently used mode), the light flashes slightly faster or slower than a rate matched to the frequency of vibration, thereby creating the illusion that the vocal folds are vibrating in slow motion. Because each image is from a different glottal cycle, the cycles must be fairly regular to show a smooth stroboscopic cycle during the running phase. If the vocal fold vibration is aperiodic, the illusion of slow motion will not occur; rather, the vocal folds will appear to “flutter .” In the stop phase, the light flashes at a rate that is matched with the frequency of the vocal fold vibration, thereby creating the illusion that the vocal folds are not moving at all.

35. Videostroboscopy is used to assess vocal fold vibration patterns, mucosal pliability, the underlying layered structure of the vocal folds, and the undersurface of the vocal fold edges. It is particularly valuable for assessing stiffness, scar, or submucosal injury; detecting small vocal fold lesions; estimating the depth of invasion of a tumor ; identifying asymmetric mass or tension; or determining the resumption of phonation after phonosurgery . Stroboscopic parameters include closure pattern, phase closure, amplitude of vibration, mucosal wave, adynamic segments, vertical closure level, symmetry, and regularity. Of these, closure and mucosal wave are often considered key indicators of function. Most stroboscopic parameters are rated at most comfortable pitch and loudness (MCPL), and then their variation with pitch and loudness changes is described.

36. CLOSURE PATTERN

37. PHASE CLOSURE Although “ closure pattern ” describes the extent of closure, “ phase closure ” describes the duration of closure. During vibration at MCPL, the glottis is typically open (opening, fully open, or closing) for approximately two thirds of one vibratory cycle and maximally closed for the remaining third. This parameter is typically rated by counting of “frames” with the use of clicks of a computer mouse. Closed time generally decreases with higher pitches and in older women; it increases in older men . Phase closure is a useful measurement in a patient who sounds breathy but achieves complete closure or during hyperfunctional patterns when the vocal folds open only briefly.

38. Amplitude of Vibration Amplitude of vibration refers to the fold's horizontal excursion from midline. Normal is defined as approximately one third of the width of the fold . In normal conditions, the vocal folds are symmetric in amplitude; that is, the maximum amplitude of the left fold is similar to the maximum amplitude of the right fold. Amplitude can be rated as a percentage of the width of the fold or on a five- or seven-point equal-appearing interval scale from normal to reduced . Amplitude of vibration is typically smaller in women than men, it generally covaries with loudness, and it varies inversely with pitch .

39. Decreased amplitude of vibration can be the result of glottic incompetence, tight glottic closure, or increased vocal-fold mass or stiffness. Decreased amplitude is common in lesions such as firm polyps, cysts, papilloma, carcinoma, Reinke's edema , scarring, and hyperfunction . Increased amplitude may be a sign of decreased tonicity, as observed in vocal-fold paresis or atrophy.

40. Mucosal Wave Mucosal wave is the vertical upheaval of the cover over the body. It occurs because of the vertical phase shift (the timing difference between the upper and lower margins of the vocal folds) that is vital to the self-oscillation of the folds . The wave is propagated from the infraglottic lip of the vocal fold, then travels up the medial edge and across the superior surface of the fold. The velocity of the mucosal wave is linked to the amount of pressure that is needed to establish phonation , and we judge mucosal wave as the distance it travels across the superior surface of the fold. Normally, this wave moves approximately half the width of the vocal fold during phonation at MCPL .

41. Increased mucosal wave (i.e., it moves farther across the fold) is observed when mucosa is abnormally pliable, such as in polypoid degeneration or when there is increased subglottal air pressure. As such, it is normally greater than half of the width of the fold for loud phonation, when subglottal air pressure is increased. Mucosal wave is decreased or even absent when the mucosa is stiff or there is minimal differentiation of the vocal fold layered structure; this occurs normally with increasing pitch and with aging. In pathologic conditions, decrease or absence of mucosal wave is seen with some lesions, scarring, or sulcus vocalis . Incomplete glottic closure resulting from aging, atrophy, or motion impairment can also lead to decrease or absence of mucosal wave.

42. Adynamic Segments Adynamic segments refers to nonvibrating areas of the vocal fold (i.e., areas that have no mucosal wave and poor amplitude of vibration). They are described by location and by the percentage of the vocal-fold surface that they cover . These stiff areas are generally related to a lesion or to a scarred segment.

43. Symmetry Symmetry is a timing parameter. It refers to the extent to which the vocal folds appear as mirror images of each other during vibration. The vocal folds should depart from midline at the same time and arrive back at midline at the same time. The asymmetry should be described whenever possible; for example, “the excursion of the right fold lags behind that of the left,” or “the folds are asymmetric at the end of tasks.” Depending on the rating scale, the parameter can be rated as either the percentage of the examination during which vibration was asymmetric or the extent of asymmetry. Asymmetric vibration raises questions about differences in mechanical properties or neurologic status between the folds . Differences between the vocal folds in position, mass, tension, elasticity, or viscosity should be further assessed.

44. Regularity Regularity (or periodicity) describes the degree to which one phonatory cycle is similar in both amplitude and time to the next phonatory cycle . The goal is to answer the question “Do the vocal folds vibrate in a regular, rhythmic pattern?” Regularity is best assessed in the locked or stop mode, but it can be estimated from the running phase as well. In the stop mode, the image appears static if the vibration is regular and appears to quiver or shake if the vibration is irregular. In running mode, the strobe light cannot adequately track fundamental frequency and adjust the illumination rate if vibration is irregular, and so quiver or shimmer appears.

45. Vibratory regularity is rated just like symmetry, either by describing the percentage of time that the vibration was regular or irregular or by describing occurrences of irregularity. It is difficult to assess the amount of aperiodicity from stroboscopy ; this would require acoustic analysis. Incidence of aperiodicity rises with age. Biever and Bless found that 85% of geriatric women demonstrated aperiodicity, compared with 30% of young women . Regular vibration depends on a steady balance between pulmonary pressure and the vocal folds . Irregular vibration can be caused by asymmetry of the mechanical properties of the vocal folds, interference with the homogeneity of the vocal folds, flaccidity, unsteady tonus, or inconsistent force. Examples are paralysis (asymmetry); a small cyst or carcinoma (homogeneity); paralysis, atrophy, or edematous lesion (flaccidity); spasmodic dysphonia or another neuromuscular disease (tonus); and functional pulmonary disease (inconsistent force ). Aperiodic vibration gives rise to acoustic noise, which can be perceived as roughness or hoarseness.

46. Vertical Closure Level Whether the vocal folds meet on the same plane is typically rated as on-plane or off-plane. Closure is off-plane typically because of either neuromuscular differences between the folds (paralysis or paresis) or laryngeal trauma or surgery.

47. HIGH SPEED DIGITAL IMAGING

48. NARROW BAND IMAGING Narrow-band imaging (NBI) is a new endoscopic imaging technique that employs the absorption characteristics of light for the detailed analysis of mucosal and vascular structures. NBI takes advantage of the differential absorption characteristics of tissues. Blue light with its shorter wavelength is better absorbed by hemoglobin . With the use of mechanical light-filtering technology to pass only the blue subset of the white light spectrum, structures with high hemoglobin concentration become more apparent with increased visualization of tissue's vascular pattern . This creates a sharper contrast for better visualization of fine mucosal detail and helps to better identify subtle abnormalities

49. NBI shows promise for improving the yield of biopsies by directing the examiner to the more “suspicious” areas, a type of optical biopsy. It is currently available for gastroscopes including transnasal esophagoscopes and flexible laryngoscopes. Clinicians are beginning to explore the utility of NBI in laryngeal and hypopharyngeal lesions

50. TREATMENT overview vocal hygiene, lifestyle and dietary advice; voice (speech) therapy; specialist therapy, for example singing therapy, osteopathy ; medical treatment ; phonosurgery

51. Vocal hygiene, lifestyle and dietary advice an explanation of how the voice works the links between lifestyle, phonatory and non phonatory vocal activities and stress on voice disorders the potentially traumatic effects to the vocal folds of 'vocally abusive behaviours', such as talking or singing too loudly, talking too fast, shouting, throat clearing and harsh coughing communicating effectively without raising or straining the voice, for example using a whistle in the school playground or using amplification devices where practical and conserving the voice where possible or in extreme situations discussing the possibility of changing jobs the importance of adequate hydration for vocal fold function, i.e. by drinking water, use of steam inhalations and avoiding excessive amounts of drinks containing caffeine, i.e. coffee, tea and colas smoking cessation, reducing alcohol and social drug consumption (particularly spirits, cannabis and cocaine ) and avoiding exposure to fumes, dust and dry air; diet and reflux reduction, for example avoiding eating late at night, large or fatty meals.

52. Voice therapy The aims of voice therapy sessions are : to help the patient find a better voice quality which is stable , reliable and less effortful to produce to make better use of vocal resonance and tonal quality to increase the flexibility of the voice by improving the pitch range and loudness without undue effort to increase the stamina of the voice

53. Various techniques include Vocal exercises with the aim of tar getting and strengthening specific muscle groups and improving glottal closure and efficiency Increasing awareness of and reducing excessive tension in the muscles around the larynx, neck and shoulders Advice on posture and improving breathing during speech Laryngeal massage General relaxation exercises and stress management Psychological counselling Remedial singing lessons.

54. Medical treatment This mainly includes treatment for acid reflux and upper respiratory tract infections and allergies. It may also include recommendations to change medication for other medical conditions, for example asthma inhalers, diuretics and other antihypertensive medication. Botulinum toxin injections into the laryngeal muscles may be used in cases of spasmodic dysphonia and arytenoid granuloma

55. Phonosurgery Microlaryngoscopic surgery : The vocal folds or occasionally false cords are inspected and lesions removed using a microscope and endoscope. The aim is usually to remove pathological tissue and attempt to restore the normal surface contour and layered structure of the vocal fold . Laryngeal injection techniques : Various synthetic, biological and autologous materials are usually injected laterally into the muscle of deep layers with a view to augmenting the vocal fold.

56. Laryngeal framework surgery : Transcutaneous surgery performed on the cartilaginous skeleton of the larynx, for example, laryngoplasty ( thyroplasty ), arytenoid adduction and cricothyroid approximation with a view to improving glottic closure and bodycover differential tone Nerve-muscle pedicle graft techniques : They are used for bulking out or restoring tone to the vocal fold. Reinnervation and electrode pacing techniques : They are used for restoring tone to the vocal fold or stimulating contraction of specific muscles.

57. Thank you It is important to use your voice for the positive because whether you know it or not your voice can do a lot