International Journal of Advancements in Research & Technology, Volume 2, Issue 7, July-2013 ISSN 2278-7763 277 VOICE THERAPY: MANAGEMENT OF BENIGN VOICE DISORDERS * 1 Dr. Sachender Pal Singh, 2Dr. Smrity Rupa Borah Dutta, 3Dr. Aakanksha Rathor 1 Postgraduate Trainee, Otorhinolaryngology Department, Silchar Medical College & Hospital,Silchar, India; 2Assistant Professor, Otorhinolaryngology Department Silchar Medical College & Hospital,Silchar, India; 3Postgraduate Trainee, Otorhinolaryngology Department, Silchar Medical College & Hospital,Silchar, India. Email: Sachender123@gmail.com ABSTRACT Voice disorders are universal problems & have significant affect on the patients’ emotional, psychological, physical, social, personal & professional well being. This is a prospective study done in the department of Otorhinolaryngology, Silchar Medical College & Hospital from June 2012 to July 2013. Thirty consecutive dysphonic patients with benign voice disorders underwent a course of voice therapy with or without undergoing surgical procedures. Pre therapy-versus-post therapy comparisons were made of self-ratings of Voice Handicap Index, Auditory-Perceptual Ratings, as well as, Visual -Perceptual Evaluations of laryngeal images. Voice therapy is an essential & effective tool to manage benign voice disorders, and provide both objective and patient-centered outcomes. To be precise, the role of voice therapy is not only therapeutic but it also helps to encourage healthy voice habits & prevent recurrence of disease after a very delicate surgery. Keywords : Dysphonia, Benign Voice Disorders, Voice therapy, Voice Handicap Index. 1 INTRODUCTION Dysphonia can be defined as any impairment of the voice or difficulty in speaking. Various dysphonic patients were diagnosed on the basis of history, clinical examination & laryngoscopy as having benign voice disorders followed by their proper management with voice therapy with or without phonomicrosurgery. Data on the prevalence of voice disorders is scarce and have ranged from 0.65 to 15 percent in the general population [1], [2]. Benign voice disorders impair communication and have important affect on public health. Roy et al reported that 29.9% of the general public had at least one voice disorder in their lifetime, 6% had a current voice disorder, and 7.2% missed one or more work days [3]. In addition to health care costs related to treatment and lost work productivity, benign voice disorders impair patients’ quality of life [4]. There has been an ideological shift in health care from 'curing' disease to 'minimizing the impact of illness on everyday activities' [5]. Voice pathologists have been using Transnasal Flexible Laryngoscopy (TFL) in their clinical practice for over 20 years [6]. The main purposes of TFL examination by a voice pathologist are to confirm the medical diagnosis [7], [8], to understand the physiological phonatory characteristics [9], [10], and to assist Plica Ventricularis (1 pt.), Parkinson’s disease (1), Puberphonia (1), Vocal Cord Paralysis (2). 2.3 Patients excluded from the study were: patients with malignant lesions, infective pathology or speech defect due to CNS lesions. All the excised tissues were sent for histopathological examination. IJOART in the design of appropriate voice therapy treatment [11], [12]. 1.1 AIMS OF VOICE THERAPY • To achieve better voice quality, this 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. 2.4 T REATMENT PROGRAMS • Explanation of normal vocal physiology to the patients. • Explanation of the disorders. • Help the patient to assume responsibility • Help the patient to understand vocal hygiene • Teaching the patients about vocal function exercises • Teaching the patients about laryngeal massage • To treat the associated laryngopharyngeal reflux • Where indicated, we considered the surgical procedures & removed the abnormal tissue giving maximum respect to the normal superficial lamina propria. • Regular follow up Vocal function exercises & laryngeal massage were chosen according to the patient’s voice disorders. 2.5 TREATMENT GOAL Primary goal of voice therapy was to maximize the efficiency of phonation & to eliminate maladaptive vocal behaviors that exacerbate these benign voice disorders 1. Auditory-Perceptual Ratings: Subjects were asked to read ‘The Rainbow passage’ (Operating Techniques in 2 MATERIALS AND METHODS Laryngology) or to count 1 to 20 & voice was record- This study is a prospective study during the period of June 2012 to July 2013 carried out at Deptt. Of Otorhinolaryngology, at Silchar Medical College, Silchar, Assam. ed. Perceptual ratings of voice quality were conduct- 2.1 SUBJECTS 2.1 Thirty consecutive subjects with benign voice disorders were recruited for the study after making a proper diagnosis on the basis of history, clinical examination & laryngoscopic examination. The patients were in the age group of 20-70 years. 2.2. Patients included in the study were: Vocal Cord Nodule (9 patients), Vocal Polyp(6 pts.), Primary Muscle Tension Dysphonia (6 pt.), Sulcus Vocalis (2 pts.), Presbylaringis(2 pts.), Copyright © 2013 SciResPub. ed with the ‘GRBAS scale’ [13]. The GRBAS scale is considered by many authors to be the most reliable auditory perceptual scale currently available for use as an outcome measure [14], [15]. 2. Quality Of Life Measures: ‘Voice Handicap Index’ was used to assess the impact of the voice in terms of physical complaint and restriction in participation in daily activities & response to treatment [16], [17], [18], [19], [20]. IJOART International Journal of Advancements in Research & Technology, Volume 2, Issue 7, July-2013 ISSN 2278-7763 3. Visual-Perceptual Ratings: It was based on comparison of Transnasal flexible laryngoscopy (TFL) done before & after the voice therapy 3 RESULTS SV PL PMTD PMTD PMTD DPV VCP PU N N N N P P P 20 10 0 BEFORE VOICE THERAPY AFTER VOICE THERAPY Fig1.GRBAS SCORE 0 SV SV PL PL PM… PM… PM… PM… PM… PM… DPV PD PU VCP PU 100 BEFORE VOICE THERAPY AFTER VOICE THERAPY Fig2.VOICE HANDICAP INDEX [Abbreviations: Sulcus Vocalis (SV), Presbylaryngis (PL), Primary Muscle Tension Dysphonia (MTD), Dysphonia Plica Ventricularis (DPV), Parkinson’s Disease (PD), Vocal Cord Paralysis (VCP), Puberphonia (PU), Vocal Cord Nodule (N), Vocal Polyp (P)] 278 apy which shows level1 evidence [21]. Voice therapy doesn’t only involve the behavioral voice therapy & laryngeal massage but also involve the vocal hygiene which covers a vital area. 4.1 VOCAL POLYP A vocal polyp never resolves with therapy alone and should be surgically removed. In one study of 24 subjects with polyps, 48 percent of patients exhibited a moderate degree of dysphonia and this was more severe in patients with polyps than in subjects with any other laryngeal lesions who were examined [22]. Different treatments are recommended for polyps that consist of a combination of phonomicrosurgery and voice therapy [23], [24], [25], [26]. In our study we gave 2 months voice therapy before the surgery but there were no improvement in symptomatology. So we went for phonomicrosurgery followed by voice therapy to prevent recurrence & till now we have not encountered any recurrence. 4.2 VOCAL CORD NODULE The etiology of vocal nodules is not known, but traditionally they are thought to be due to voice abuse [27] rather than overuse [28]. A double-blind study into an evaluation of hydration against placebo as a treatment for vocal nodules was also convincing [29]. There is no evidence for advising absolute voice rest as this is usually too difficult as patients will not be able to do his work & have to seclude himself [30]. Treatment by voice therapy and laryngoscopic review is preferable to treatment by surgery followed by therapy [31]. In our study most of the patients were having problem with their mouth opening & posture while talking & history of voice misuse & abuse. We advised proper vocal hygiene, good posture during talking & behavioral voice therapy & in some laryngeal massage to treat hyperfunction, before the surgery & then after 2 days of absolute voice rest we continued with the same. We started the therapy before the surgery to prevent damage to the vocal cords immediately postoperatively with the faulty trials of voice therapy techniques by the patients. With this we got no recurrence & all of the patients are doing well. In early vocal cord nodules we didn’t plan phonomicrosurgery & they had showed very good results with only voice therapy. IJOART Fig3.Dysphonia plica ventricularis (before & after voice therapy), laryngoscopic view 4.3 PRESBYLARINGIS Such patients don’t want voice therapy but usually requires only reassurance that the disorder is self limited. If treatment is indicated, then the vocal hygiene, behavioral voice therapy & laryngeal massage are advised to make the laryngeal musculature strong and to improve vocal control. In our study we did the same & a very good result was achieved. Fig4.Primary muscle tension dysphonia (before & after voice therapy), laryngoscopic view Fig5. Vocal cord nodule (before & after voice therapy), laryngoscopic view 4 DISCUSSIONS In the literature, there are few reports of efficacy of voice therCopyright © 2013 SciResPub. 4.4 SULCUS VOCALIS Voice therapy helps in preventing hyperfunction & mild dysphonic patients can be managed with voice therapy alone. In our study we got 2 cases which were having slight phonatory gap. We tried voice therapy first & they did well with that. 4.5 PRIMARY MUSCLE TENSION DYSPHONIA It is often a 'diagnosis of exclusion', i.e. 'the vocal cords look and move normally'. Management includes techniques to reduce vocal fold, laryngeal & pharyngeal regions muscle tension [32]. In our study we got only 6 cases of MTD & have managed them with the vocal hygiene, behavioral voice therapy & laryngeal massage & achieved satisfactory results. One of them was very interesting case, as he develops the dysphonia after an incident of cut throat. We managed the pt. primarily for cut throat & after that we gave him voice therapy & he improved a lot with that. On laryngoscopy he was not having any trauIJOART International Journal of Advancements in Research & Technology, Volume 2, Issue 7, July-2013 ISSN 2278-7763 ma in the larynx. • 279 To relax the excessively tense musculature which inhibits normal phonatory function & to reduce ody- 4.6 DYSPHONIA PLICA VENTRICULARIS We got only one such case. True vocal cords were normal & there was no associated pathology with them. But at the time of onset of symptoms he was having anxiety & depression due to failure in exams. We tried voice therapy & psychotherapy and patient has improved satisfactorily. 4.7 PUBERPHONIA We got only 1 case of puberphonia. We advised him voice therapy programe & he improved with that to his satisfaction. nophonia. • Manual Laryngeal Musculoskeletal Reduction Technique was first discussed by Aronson (1990). He described that, on giving massage the muscle tension of the extrinsic laryngeal musculature decreases & massage eliminates the inappropriate muscle activity during phonation. INTRODUCTION TO SOME OF THE TECHNIQUES: 4.8 VOCAL FOLD PARALYSIS In unilateral or bilateral vocal cord paralysis we should wait for 9-12 months for spontaneous recovery, but if the patient is experiencing serious degree of aspiration of food or fluids or is very sick or terminally ill then phonosurgery may be considered to reduce the problem. We got only 2 cases of unilateral vocal cord paralysis with no significant aspiration. We advised them the appropriate vocal function exercise with regular follow up & now the patient is having less dysphonia & his transnasal flexible laryngoscopy is having significant changes. RESONANT VOICE: Titze (2003) states, “resonant voice engages the vocal tract for maximum transfer of power from glottis to lips & ultimately all the way to the listener”. Glottic configuration observed in the resonant voice was, in fact, the glottic configuration known to produce maximum transfer of sound through the vocal tract. Humming: It results in easy, relaxed voice production by increasing proprioceptive feedback from oronasal resonance & decreasing feedback from laryngeal resonances (Colton & Casper 1990). 4.9 VOICE THERAPY CHEWING: Chewing while phonation results in the most natural & basic mode of voice production & restrict any inappropriate muscle’s action [Froeschels (1943, 1952)]. • Reduces pitch & muscle tension in voice production VOCAL HYGIENE: It includes the methods to alter the inappropriate voice use adapted by the patient. The methods include patients’ education and their awareness, training & abuse identification. Last but not the least hygiene program must sum up with the modification stage, to reduce the occurrence of inappropriate behaviors (Andrews, 2001). • Encourages mouth opening & reductions of mandibular tensions. IJOART SYMPTOMATIC VOICE THERAPY (Daniel Boone, 1971): Based on modification of systems: 1. Appropriate tongue position, 2. Alteration of loudness, 3. Chewing exercise, 4. Digital manipulation, 5. Ear training, 6. Elimination of abuses, 7. Elimination of hard glottal attack 8. Explanation of the problem, 9. Open mouth exercises 10. Pushing approach, 11. Relaxation 12. Respiration training, 13. Voice rest, 14. Yawn sigh approach PSYCHOGENIC VOICE THERAPY: Focuses on identification and modification of the emotional and psychosocial disturbances associated with the onset and maintenance of voice problem. PHYSIOLOGIC VOICE THERAPY: Voice disorders are best treated by modifying the underlying physiology of voice production (stemple, 2000; stemple et al 2000) Three key components: 1. Improves the balance between the respiration, phonation & resonance. 2. Improves the strength, balance, tone & stamina of the laryngeal muscles. 3. Develops a healthy mucosal covering of the true vocal folds. Examples: vocal function exercises, resonant voice therapy and the accent method of voice therapy CIRCUMLARYNGEAL MASSAGE & LARYNGEAL MANUAL THERAPY: Copyright © 2013 SciResPub. • Reduction of hard glottal attacks YAWN –SIGH APPROACH (Boone): Performing a yawn just prior to phonation would result in phonation with a relax vocal tract as it expands the pharynx & stretches & then relaxes the extrinsic laryngeal muscles, thus lowering the larynx in the neck to a more neutral position & permit a more forward placement of the tongue in the oral cavity. ACCENT METHOD (Svend Smith (Harris, 2000)): Accentuated vowel productions with abdominodiaphragmatic breathing optimize the respiratory phonatory balance & bring about proper patterns of vocal cord closure (kotby, Shiromoto, & Hirano, 1993). It is based on the myoelstic aerodynamic theory of vocal fold vibration proposed by van den berg in 1958(Harris, 2000) It addresses pitch, loudness & timbre simultaneously rather than focussing separately upon each of these vocal parameters. CONFIDENTIAL VOICE (Colton & Casper (1990): It reduces the vocal intensity, muscular tension & collision impact of vocal cord during phonation as well as eliminates the strained or tight breathing pattern (Casper, 1997). VOCAL FUNCTION EXERCISES: These exercises strengthen & rebalance the subsystems involved in phonation (Respiration, Phonation & Resonance) (stemple 1993). Used in: vocal fold lesions, muscle tension dysphonia, hypofunctional voice disorders. PLACE THE VOICE (Boone, 1988): He proposed that individuals with vocal hyperfunction should be trained to shift the vocal tone away from the neck & into the midface region using nasal sounds to enhance the patients’ awareness of resonance in the facial area. PUSHING EXERCISE: These are based upon the premise that the rapid & voluntary contraction of 1 set of muscles would result in the contraction of other groups of muscles (Froschels et al 1955). Boone (1971) noted the tendency for the larynx to undergo IJOART International Journal of Advancements in Research & Technology, Volume 2, Issue 7, July-2013 ISSN 2278-7763 reflexive closure during moments of heavy exertion. It results in increase in glottal closure & loudness. ABDOMINAL BREATHING: 1. To maintain appropriate subglottal air pressure. 2. To avoid shallow, upper chest breathing. 3. To avoid phonation on residual air. 280 Muscle tension dysphonia To alter the state of tight vocal tract muscles and to improve the range of movement of the laryngeal joints Correction of posture, abdominal breathing, open mouth approach, circumlaryngeal massage technique, chewing exercise, yawn sigh approach, resonant voice Puberphonia Phonate at a low pitch, to fully utilize the phonatory & respiratory musculature Dysphonia plica ventricularis Restore true vocal fold health, Resolve the false fold phonation Unilateral vocal fold paralysis To improve glottal closure & at the same time to avoid undesirable compensatory behaviours, progressive development of optimal breathing, abdominal support, & gentle improvement of intrinsic muscle strength & agility, without supraglottal hyperfunctional compensation Parkinson’s disease To improve glottal closure, to increase effort & coordination, to increase fundamental frequency range & to increase overall loudness Resonance, phonation of vowel with glottal attack, chewing, relaxation techniques, half swallow boom techniques, use of vegetative sounds like cough or throat clearing to initiate voice, digital manipulation of thyroid cartilage during vowel production . Relaxation, whistling & blowing techniques, inspiratory phonation, yawn sigh method, Laryngeal manipulation & circumlaryngeal manual therapy, Psychotherapy Abdominal breathing, resonant voice, yawn sigh method, half swallow boom technique, lip & tongue trill, pushing exercises, accent method, manual laryngeal muscle tension reduction techniques Lee Silverman Voice Treatment HALF – SWALLOW BOOM TECHNIQUE: The swallow procedure maximizes closure of the larynx “Boom” is a single word composed of voiced sounds that is able to be produced as air is released from the constricted larynx and the oral opening is minimized Produces posterior pressure on the larynx This technique is a slow progression to get the patient to lower their pitch Used to improve glottal closure. INHALATION PHONATION: Boone (1966) held that phonation during inhalation results in adduction of the true vocal cords without associated false vocal folds adduction. CHANT-TALK: Encourages an easy flow of phonation & reduces laryngeal & vocal tract tensions. IJOART Reduces the tendency towards hard glottal attack & increased force of vocal fold contact. Increases proprioceptive feedback as vibrations are felt through the nose & cheek areas, thus helping the patient to reduce focus on the larynx. Table 1 Voice therapy for different voice disorders VOICE DISOR ORDERS Early vocal cord nodule/poly p Pres bylaryngis/ Sulcus vocalis AIMS AND GOALS VOICE THERAPY PROGRAM To minimize detrimental vocal behaviors & learn healthy voice production, use the pts. natural pitch, reduces hoarseness, ensure relaxed & easy movements of vocal cords, to increase breath support, to decrease the head & neck muscles tension (compensatory behaviors) To improve vocal fold closure, to strengthen & rebalance the laryngeal musculature and co-ordinate the subsystems of voice production Vocal hygiene, correct posture, confidential voice, resonant voice, vocal function exercise program Copyright © 2013 SciResPub. Respiratory retraining, Relaxation techniques , laryngeal adduction exercises, vocal function exercise program 5 CONCLUSION Voice therapy is an essential & effective tool to manage benign voice disorders, and provide both objective and patientcentered outcomes. Improvements in perceptual and functional outcomes were related to improved vocal efficiency resulting from simultaneous altering of all phonatory subsystems (i.e., Phonation, Resonance and Respiration). Although immediate treatment effects were encouraging, long-term follow-up are needed to sustain the results. To be precise, the role of voice therapy is not only therapeutic but it also helps to enIJOART International Journal of Advancements in Research & Technology, Volume 2, Issue 7, July-2013 ISSN 2278-7763 courage healthy voice habits & prevents recurrence of disease after a very delicate surgery. Although there is inter & intra observer grading differences in Auditory-Perceptual Ratings & Quality Of Life Measures and there may be mismatch between the two methods but clinically these variations are small enough to permit practical evaluation of the patient’s voice & are very useful during follow up to both the patient as well as the trainer. 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Efficacy of the accent method of voice therapy. Journal o f Voice. 1991; 5: 316-20. IJOART Copyright © 2013 SciResPub. Author Profile Dr. Sachender Pal Singh passed M.B.B.S degree from Mahrishi Markendeshwar Institute of Medical Science & Research, Haryana in 2011 and is presently pursuing M.S degree in Otorhinolaryngology (2011-2014) from Silchar Medical College, Assam, India. IJOART International Journal of Advancements in Research & Technology, Volume 2, Issue 7, July-2013 ISSN 2278-7763 282 IJOART Copyright © 2013 SciResPub. IJOART