Transcription

MedicineTodayPEER REVIEWED ARTICLEPOINTS: 2 CPD/1 PDPHoarsenessa guide to voice disordersHoarseness is usually associated with an upper respiratory tract infection or voice overuseand will resolve spontaneously. In other situations, treatment often requires collaborationbetween GP, ENT surgeon and speech pathologist.RON BOVAMB BS, MS, FRACSJOHN McGUINNESSFRCS, FDS RCSIN SUMMARYDr Bova is an ENT, Head andNeck Surgeon and Dr McGuinnessis ENT Fellow, St Vincent’sHospital, Sydney, NSW.Voice disorders are common and attributable toa wide range of structural, medical and behavioural conditions. Dysphonia (hoarseness) refersto altered voice due to a laryngeal disorder andmay be described as raspy, gravelly or breathy.Intermittent dysphonia is normally always secondary to a benign disorder, but constant or progressive dysphonia should always alert the GP tothe possibility of malignancy. As a general rule, apatient with persistent dysphonia lasting morethan three to four weeks warrants referral forcomplete otolaryngology assessment. This is particularly pertinent for patients with persistinghoarseness who are at high risk for laryngeal cancer through smoking or excessive alcohol intake,and for patients with a family history or personalhistory of head and neck cancer.The mechanism of voice production isdescribed in the box on page 39.Inflammatory causes of voicedysfunctionAcute laryngitisAcute laryngitis causes hoarseness that can resultin complete voice loss. The most common causeis viral upper respiratory tract infection; othercauses include exposure to tobacco smoke and ashort period of vocal overuse such as shouting orsinging. The vocal cords become oedematouswith engorgement of submucosal blood vessels(Figure 3).Treatment is supportive and aims to maximisevocal hygiene (Table), which includes adequatehydration, a period of voice rest and minimisedexposure to irritants. Antibiotics are not indicatedif a viral infection is suspected, and corticosteroidsare rarely indicated for this common condition.Effortful speaking or singing during an acute attackof laryngitis may lead to vocal cord haemorrhage Intermittent dysphonia is usually always secondary to a benign disorder. Constant orprogressive dysphonia should always alert the GP to the possibility of malignancy.Radiological investigations such as CT scans miss the majority of vocal cord lesions.Flexible endoscopic nasolaryngeal examination is the most sensitive investigatory tool.Treatment for chronic laryngitis due to laryngopharyngeal reflux is an eight- to12-week empirical course of a proton pump inhibitor as well as dietary and lifestylemodification.Muscle tension dysphonia is a common cause of hoarseness and results from excessiveand unnecessary tension of laryngeal muscles during phonation. Speech therapy is thecornerstone of management. A patient presenting with persisting hoarseness who is at high risk of laryngealmalignancy through smoking, excessive alcohol intake or a history of head and neckcancer should be referred for early specialist assessment. 38MedicineToday February 2007, Volume 8, Number 2Permission granted for use by Entthyroid.com.au for educational purposes. Medicine Today 2007. Copyright for illustrations as stated.

How is voice produced?Voice production is a complex process requiring co-ordination between the lungs, larynx, pharynx and oral cavity. The lungs act like a powersource, blowing expired air up through the vocal cords in the larynx (Figures 1a and b). The vocal cords vibrate hundreds of times per second,producing sound, the resonance of which is modified by muscular activity in the pharynx and oral cavity. Normal voice requires functioning vocalcords that are lined by smooth, well hydrated epithelium (Figure 2). Even the slightest alteration in vocal cord structure can result in hoarseness.TongueEpiglottisEpiglottisTracheaFalse vocalcordFalse vocalcordsThyroidcartilage copyrightLaryngealventricleTrue vocalcordsCricoidcartilageOesophagus copyrightThyroidTracheaFIGURES 1A AND 1B CHRIS WIKOFF, 2007True vocalcordFigure 1a (top left). Laryngeal structures as seen from above during examination.Figure 1b (top right). Coronal section through the larynx. Note the true vocalcords are separated by a space (laryngeal ventricle) from folds of supraglottictissue (false vocal cords).Figure 2 (left). Typical view obtained of a normal larynx using a flexiblenasendoscope. The vocal cords are pale, smooth and easily visualised.or formation of a haemorrhagic polyp. This is particularly relevant for a singer or other professionalvoice user who attempts to resume prelaryngitisvocal demands too early.Chronic laryngitisChronic laryngitis (chronic inflammation of thelaryngeal mucosa) often impairs mucociliarytransport, such that mucus that would normallybe transported efficiently into the pharynx andswallowed may collect in the back of the larynxand pharynx. Symptoms are varied and include: hoarseness, which often comes and goes vocal fatigue, especially towards the end ofthe day a feeling of throat irritation or drynessmild throat discomfort with speaking andswallowing chronic cough, often with severe bouts oflaryngospasm where there is a chokingsensation; patients may describe it as aninability to get their breath sensation of postnasal drip with chronicthroat clearing and a feeling of retainedmucus in the back of the throat sensation of a lump in the throat.Chronic laryngitis can be caused by multipleirritants, including: tobacco smoke environmental or occupational pollutantsMedicineToday February 2007, Volume 8, Number 2Permission granted for use by Entthyroid.com.au for educational purposes. Medicine Today 2007. Copyright for illustrations as stated.39

HoarsenesscontinuedBenign lesions of the vocalcordsTable. Measures to improvevocal hygieneA period of voice rest, especially foracute laryngitisHydration with noncaffeinated drinks,especially during periods of heavyvoice useLimiting of vocal loudness (e.g. use ofa microphone for teaching or publicspeaking)Avoidance of habitual and frequentthroat clearingAvoidance of irritants, including passivesmokingHumidified environment (e.g. use ofmenthol or eucalyptus inhalations)Figure 3. Acute laryngitis. Avoidance of medications that havean anticholinergic drying effectNot smokingSpeech therapy or vocal training,especially for professional voice users laryngopharyngeal reflux (this isdescribed in the box below).fungal laryngeal infection, whichmainly occurs in immunosuppressedpatients but may also be seen inpatients taking inhaledcorticosteroidssystemic autoimmune causes such asWegener’s granulomatosis, amyloidosis,systemic lupus erythematosus andrelapsing polychondritis, which areextremely rare.Vocal cord nodulesVocal cord nodules are small, fibrous,bilateral swellings that develop on theanterior vocal cords as a result of excessive voice use (Figure 5). They are analogous to calluses and frequently found insingers and children who shout excessively. Patients complain of fluctuatinghoarseness, often associated with intermittent sudden changes in vocal pitch.Voice therapy usually causes the nodulesto regress. Persistent symptomatic nodules may be treated with microsurgicalexcision.Vocal cord polypsVocal cord polyps are unilateral pedunculated lesions that commonly occur inmen with a history of voice abuse andheavy smoking (Figure 6). The aetiologyis unknown but the polyps are often veryvascular, which makes repeated traumaa probable causative factor. Microsurgicalexcision is nearly always required for bothdiagnostic and therapeutic purposes.Laryngopharyngeal reflux and chronic laryngitisLaryngopharyngeal reflux, which occurs when acid refluxes through an incompetent upper oesophageal sphincter and irritates the larynx, is acommon cause of chronic laryngitis. Even small amounts of acid reflux can cause minor laryngeal oedema resulting in hoarseness in additionto the other symptoms of chronic laryngitis, especially chronic throat mucus clearing and dry cough. Despite having concurrent gastrooesophageal reflux disease (GORD) due to lower oesophageal sphincter dysfunction, patients may not complain of heartburn or chest painbecause the oesophageal mucosa is much more resistant to small quantities of acid reflux.A classic feature of severe laryngopharyngeal reflux is granulation tissue overlying theposterior vocal cord but this is relatively uncommon; a reflux granuloma is shown in Figure 4.Treatment for chronic laryngitis due to laryngopharyngeal reflux is an eight- to 12-weekempirical course of a proton pump inhibitor as well as dietary and lifestyle modification,including elevation of the head of the bed. Speech therapy is useful, especially for patientswith reflux granulomas, and aims to modify vocal cord closure patterns to minimisecontact trauma between the posterior cords. Microsurgical removal is sometimes requiredfor granulomas that are large or refractory to conservative measures. A relatively newtreatment for stubborn granulomas involves paralysing the affected vocal cord by injectingbotulinum toxin type A (Botox, Dysport). This minimises phonatory trauma and allows thegranuloma to resolve, but severe breathy dysphonia lasting months is unavoidable.Figure 4. Reflux induced granuloma of the leftPatients with severe or persistent reflux symptoms refractory to medical managementposterior vocal cord. This lesion and the patient’smay require comprehensive evaluation by a gastroenterologist.symptoms resolved with antireflux therapy.40MedicineToday February 2007, Volume 8, Number 2Permission granted for use by Entthyroid.com.au for educational purposes. Medicine Today 2007. Copyright for illustrations as stated.

HoarsenesscontinuedFigure 5. Vocal cord nodules in an amateursinger.Figure 6. A vocal cord polyp in a young healthyman just prior to microsurgical excision.of transmission during vaginal deliveryin the presence of a history of genitalwarts in pregnancy has been estimated tobe approximately 0.5%.1 Laryngeal papillomas may present in adulthood but arerare after the age of 30 years. The mostcommon presenting symptom in olderchildren and adults is hoarseness, but stridor and respiratory compromise may beseen in severe widespread disease.The mainstay of treatment has beenlaser microsurgical removal, but diseaserecurrence is the norm and many patientsrequire multiple operations. Intralesionalinjection of antiviral agents such as cidofovir (Vistide) is a relatively new treatmentfor severe cases. Rarely, recurrent papillomatosis is complicated by malignanttransformation (approximately 0.5%) orextension in the tracheobronchial tree – aserious and often incurable condition.Malignant lesions of the vocalcordsFigure 7. Severe diffuse laryngeal papillomatosis obscuring and affecting the entiresupraglottic larynx. This patient presentedwith severe hoarseness.Figure 8. Exophytic tumour affecting theright vocal cord. This lesion was successfullytreated with endoscopic laser microsurgicalexcision.Laryngeal cystsLaryngeal cysts can occur throughout thelarynx and are usually due to mucus retention in the tiny mucus secreting glands inthe submucosa of the entire upper aerodigestive tract. Surgical excision is usuallyrequired when they are located on thevocal cords and result in hoarseness.are often assumed to be men when usingthe telephone. Examination reveals diffuseboggy swelling of both vocal cords.Smoking cessation and speech therapyare usually successful, but intractable casesrequire microsurgical excision of theredundant mucosa with aspiration of theoedematous fluid.Reinke’s oedemaReinke’s oedema (oedema in the superficial layers of the vocal cord) is a commoncondition caused by long term exposure to irritants such as cigarette smoke.This interesting condition is more common in women than men and presentswith chronic raspy dysphonia – pitch isreduced to the point that affected womenRespiratory papillomatosisRespiratory papillomatosis is caused byhuman papilloma virus (HPV) andresults in multiple warty lesions throughout the larynx (Figure 7). Infection mostcommonly occurs at the time of birth,and affected individuals usually presentwith hoarseness, stridor or ‘noisy breathing’ between 2 and 4 years of age. The risk42Squamous cell carcinomaSquamous cell carcinoma (SCC) of thelarynx is the most common malignancyof the upper aerodigestive system. It mostcommonly affects men aged in their 50s or60s, but the incidence in women is increasing. The major risk factors are smokingand alcohol use, but 5% of cancers occurin patients who do not smoke or drinkexcessively.Vocal cord cancer presents with progressive hoarseness; stridor and dysphagiaoccur in advanced disease. Early stagetumours appear as exophytic or ulcerative lesions affecting the free edge of thevocal cord; they rarely metastasise andhence have an excellent prognosis (Figure8). Treatment options include radiotherapy and surgical resection. Endoscopicmicrosurgical laser resection is gainingacceptance as the surgical treatment ofchoice for early stage vocal cord cancer.Cancers affecting the supraglottis andsubglottic larynx can also produce dysphonia as a result of encroachment into thelaryngeal airway, by direct extension to theMedicineToday February 2007, Volume 8, Number 2Permission granted for use by Entthyroid.com.au for educational purposes. Medicine Today 2007. Copyright for illustrations as stated.

Hoarsenesscontinuedvocal cords or infiltration into the intrinsicmuscles of the larynx. Initial symptoms areoften subtle, so patients frequently presentwith advanced disease. Common presenting symptoms include stridor, hoarseness,haemoptysis and dysphagia. Cervical necknodal metastasis is very common withsupraglottic cancers, and hence patientsmay present with a neck lump. Treatmentinvolves surgery, radiotherapy or combined modality therapy.Neuromuscular disordersMuscle tension dysphoniaMuscle tension dysphonia is a relativelycommon yet poorly understood cause ofhoarseness. It is thought to result fromexcessive and unnecessary tension oflaryngeal muscles during phonation. Onexamination, patients typically constricttheir supraglottic laryngeal muscles to thepoint where it can be difficult to visualisetheir vocal cords during vocalisation. Itmay develop as a compensatory vocaltechnique in patients with glottic insufficiency such as age related vocal atrophy;alternatively, it may occur as a primaryimbalance of laryngeal muscle use. It isthought to be compounded by stress oranxiety.The major complaint is usually fluctuating hoarseness and vocal fatigue,sometimes with a feeling of tightness ordiscomfort in the throat. It is importantto ask about reflux laryngitis because thismay be an exacerbating factor in a significant number of patients. Speech therapyto reduce excessive laryngeal tensionduring voice use is the cornerstone ofmanagement.Spasmodic dysphoniaUntil relatively recently, spasmodic dysphonia was considered a psychiatric diagnosis. It is now recognised as a regionaldystonic reaction of the larynx characterised by involuntary spasms of the vocalcords. Like many dystonic reactions, itis absent at rest (therefore breathing isnormal) but precipitated by speaking.44The most common form is adductorspasmodic dysphonia, in which there isincreased closure of the vocal cordsresulting in speech that is punctuated byfrequent strangulated and constrictedstops. Intelligibility of the patient may beimpaired markedly. Abductor spasmodicdysphonia, in which sudden increasedopening of the vocal cords occurs andresults in a breathy voice, is far less common. Other neurological symptoms aresometimes present in patients with spasmodic dysphonia, including tremors andfacial dystonia.Treatment of spasmodic dysphonia hasbeen revolutionised by injection of botulinum toxin type A to temporarily paralysethe hyperfunctioning muscle group. Thisis done as an outpatient procedure usingelectromyographic guidance. Excellentresults lasting three to four months can beexpected.PresbyphoniaPresbyphonia is hoarseness resulting fromage related laryngeal changes. It is verycommon in elderly patients and characterised by an intermittent hoarse, breathyor wavery voice that often fatigues easily.Laryngeal muscle atrophy results in thevocal cords having a bowed appearanceand, in combination with age related lossof vocal cord tone and elasticity, leads tovarying degrees of hoarseness. Elderlypatients may also be taking medicationswith anticholinergic side effects, whichcontribute to vocal dryness.Speech therapy helps to increase laryngeal muscle tone and improve voice quality. Injection of fat or synthetic materialsinto the vocal cords is possible in severecases, but it is rarely indicated.Vocal cord paralysisVocal cord paralysis most commonlyoccurs as a consequence of paralysis of therecurrent laryngeal nerve (a distal branchof the vagus nerve that innervates theintrinsic laryngeal muscles and ascendsfrom the mediastinum into the root of theneck along the tracheo-oesophagealgroove and is intimately associated withthe back of the thyroid gland). Less commonly, the vagus nerve may be paralysedhigher in the neck or skull base, resultingin palatal asymmetry in addition to vocalcord paralysis. Patients present with abreathy voice, reduced vocal pitch andsignificant vocal fatigue. The paralysedcord often lies in an open position, resulting in a large glottic gap that can lead tosignificant aspiration.The common causes of vocal cordparalysis are: iatrogenic (thyroid or thoracic surgery) idiopathic – although unproven, viralneuritis is suspected to be a relativelycommon aetiological factor becauserecurrent laryngeal nerve palsy oftenoccurs after an upper respiratory tractinfection cancer (thyroid, laryngopharynx,lung, oesophageal) thoracic aortic aneurysm cerebrovascular accident, head trauma(central vagal paralysis).When the cause is unknown, patientsrequire a comprehensive radiologicalassessment of the head, neck and chest toexclude malignant infiltration of the vagusor its recurrent laryngeal nerve branch.Subsequent management depends on thecause of the nerve palsy. The treatmentoptions to rehabilitate the paralysed vocalcord include: Nonsurgical management. If there is noaspiration and the patient is happywith the voice, the paralysed cord canbe left alone with the expectation thatpartial compensation will occur afterapproximately six months. In caseswhere the nerve is bruised ortemporary neuritis is suspected afteran upper respiratory tract infection,complete recovery can be expected.Injectionthyroplasty. This involves injection of fat or artificial substances(Gelfoam, Teflon) into the paralysedvocal cord to medialise it in anattempt to reduce the glottic gap. TheMedicineToday February 2007, Volume 8, Number 2Permission granted for use by Entthyroid.com.au for educational purposes. Medicine Today 2007. Copyright for illustrations as stated.

procedure requires a short generalanaesthetic and has minimalmorbidity.Laryngeal framework surgery. Thisinvolves insertion of a Silastic orGortex implant into the vocal cord viaa small window through the thyroidcartilage resulting in medialisation ofthe paralysed cord. The procedure canbe performed under local anaestheticand requires an overnight stay inhospital.patient who smokes or has a high alcoholintake and when it is associated with otherthroat symptoms such as dysphagia,stridor or haemoptysis. Radiologicalinvestigations such as CT scans detectonly large lesions and miss the majority ofvocal cord lesions. Flexible endoscopicnasolaryngeal examination is the mostsensitive investigatory tool and can be performed easily in the office setting. Treatment varies according to the cause butoften requires collaboration between GP,ENT surgeon and speech pathologist. MTFinal commentsEveryone experiences hoarseness at sometime in their lives. Fortunately it is usuallyassociated with an upper respiratory tractinfection or voice overuse and will resolvespontaneously. Persistent unexplainedhoarseness should alert the GP to the possibility of a benign or malignant laryngeallesion, especially when it occurs in aReferenceWho wants your opinion?WE DO. Did you find a particulararticle in this issue helpful in yourpractice? Do you have something tosay about an article we havepublished or some of the opinionsexpressed? Write and tell us, and wewill consider your letter forpublication. We are more likely toprint short letters (no longer than 250words), so please be succinct.Write to: Medicine Today,PO Box 1473, Neutral Bay, NSW 20891. Silverberg MJ, Thorsen P, Lindeberg H, GrantLA, Shah KV. Condyloma in pregnancy is stronglypredictive of juvenile-onset recurrent respiratorypapillomatosis. Obstet Gynecol 2003; 101: 645-652.DECLARATION OF INTEREST: None.Permission granted for use by Entthyroid.com.au for educational purposes. Medicine Today 2007. Copyright for illustrations as stated.

vocal hygiene A period of voice rest, especially for acute laryngitis Hydration with noncaffeinated drinks, especially during periods of heavy voice use Limiting of vocal loudness (e.g. use of a microphone for teaching or public speaking) Avoidance of habitual and frequent throat c