Vocal cord disorders present with a variety of symptoms including dysphonia, respiratory symptoms, and stridor. When evaluating symptoms, a complete history and through head, neck, and neurologic examinations are necessary. If dysphonia persists for greater than 4 w or there is associated smoking, then larngoscopy is necessary to evaluate the vocal folds. Empiric treatment of dysphonia is not recommended without direct visualization of the vocal folds. Most masses of the vocal folds are benign and resolve with voice hygiene and speech therapy. Surgery is reserved for persistent symptomatic nodules and cancerous lesions.
Key points
- •
The Clinical Practice Guideline for Hoarseness from 2018 American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF) emphasizes no empiric treatment of dysphonia with antibiotics, anti-reflux medications, corticosteroids, or speech therapy without direct visualization of vocal folds to ensure correct diagnosis and avoid medication side effects or potential delayed diagnosis of carcinoma.
- •
Direct visualization of the vocal folds is necessary for dysphonia lasting more than 4 weeks.
- •
Voice hygiene and speech therapy are used in the treatment of most vocal fold conditions.
- •
Adjunct treatments for vocal fold disorders include steroid and botulinum toxin injections and potentially surgery.
Introduction
Vocal cord disorders are a diverse group of conditions that cause symptoms of hoarseness, breathing, and stridor. Hoarseness is the patient’s complaint of vocal dysfunction, whereas dysphonia is the clinical term for changes in voice related to altered pitch, quality, or effort.
Dysphonia is often self-limited and may be related to viral infections, but other conditions such as reflux, functional disorders, structural changes to the vocal cords, and overuse are common.
The morbidity and economic costs of dysphonia are significant. From an analysis of National Health Interview Survey data, the prevalence of dysphonia among United States (US) adults in the preceding 12 mo has increased from 17.89 million (7.62%) in 2012 to 29.92 million adults (11.71%) in 2022. Young adults 18 to 29 years old, women, non-Hispanic, and non-Caucasian were all more likely to report dysphonia. An estimated 28 million people experience voice disorders daily in the US, with 7.2% missing at least 1 workday annually and 10% filing for short-term disability. Those who file for short-term disability lost a mean of 39.2 days of work, with a mean of $4437.89 in lost wages. Quality-of-life decreases are significant in those who depend on their voice, resulting in lost productivity, social isolation, and depression. While often self-limited, treatment costs about $13.5 billion annually, comparable to other chronic diseases such as diabetes and chronic obstructive lung disease. Based on an analysis of a large US claims database between 2004 and 2008, direct costs due to laryngeal disorders were estimated to be between $577.18 and $953.21 per person per year.
When dysphonia does not resolve in 4 weeks, further visualization and evaluation of the larynx is warranted with laryngoscopy and follow-up with a multidisciplinary team including an otolaryngologist, speech therapist, and vocal pedagogue may be necessary. More studies and advances in voice therapy are needed to best identify and treat vocal cord disorders.
Anatomy
The larynx is a cartilaginous structure with the associated muscles and ligaments in the anterior neck, which protects the lower respiratory tract from aspiration and is involved in phonation. The thyroid and cricoid cartilages form the supporting structure, and the epiglottis covers and protects the trachea during swallowing. The paired arytenoid, corniculate, and cuneiform cartilages form the support for the vocal folds or cords. The vocal folds are composed of the superior, or false, vocal folds, which do not contain muscle, and the inferior, or true vocal folds, which do contain a muscular element and are able to oppose each other ( Fig. 1 ). In contrast to the rest of the respiratory tract, the vocal folds are covered by squamous epithelium instead of ciliated columnar epithelium.
Innervation of the larynx is via the inferior, or recurrent, laryngeal nerve, and superior laryngeal nerve. The superior laryngeal nerve arises from the vagus nerve at the inferior ganglion and innervates the cricothyroid muscle via its external laryngeal branch.
The inferior recurrent nerves are asymmetric, with the left arising from the vagus nerve in the thorax, then looping under the aortic arch before passing superiorly to enter the larynx. The right inferior, or recurrent, laryngeal nerve arises from the vagus nerve in the neck, loops under the subclavian artery then rises superiorly to enter the larynx ( Fig. 2 ). The recurrent nerves innervate the intrinsic muscles of the larynx, except the cricothyroid muscle.
The intrinsic laryngeal muscles have different functions in modulating the vocal folds. The cricothyroid muscle elongates the vocal folds, leading to higher pitch. The posterior cricoarytenoid muscles cause abduction, or opening, of the vocal folds. The lateral, or anterior, cricoarytenoid muscles cause adduction, or closing of the vocal folds. The thyroarytenoid muscles relax and approximate the vocal folds. The aryepiglottic muscles adduct the aryepiglottic folds. The arytenoid muscles adduct the vocal folds.
The extrinsic muscles cause movement of the larynx and are innervated by cervical nerves and various branches of the vagus nerve and pharyngeal nerves.
History/physical examination
A thorough history is essential to identify individuals with dysphonia that need expedited evaluation with laryngoscopy and urgent specialist referral. Complaints about the quality of voice range from roughness, decreased range, pitch instability, and early fatigue. History includes duration, course, exact nature of concern, and associated symptoms such as anterior cervical discomfort, use of substances and medications, medical conditions including esophageal reflux, recent surgeries, and procedures, particularly endotracheal intubation, and occupation. An acute onset associated with a viral syndrome will resolve in 7 to 10 days and does not require further workup.
Other etiologies include thyroid disease, which is associated with muffling of the voice, decreased range, and early vocal fatigue; pulmonary disease, which can decrease the power of air supply leading to weak voice; as well as neuromuscular disorders and posture, which can affect generation of air flow and positioning of the vocal tract. In addition, dairy products and medications that thicken mucus or decrease moisture of the vocal folds, like antihistamines, decongestants, menthols, and inhaled corticosteroids, may decrease compliance of the vocal folds leading to less vibration.
Physical examination should include observation of gait and posture, noting symmetry, smoothness of motion, and weakness. As the patient speaks, note the quality, pitch, and volume of speech. Examine the oropharynx for lesions or erythema. Palpation of the neck is a key to identify overused musculature, focusing on the anterior cervical musculature, cricothyroid space, tongue base above the hyoid, and the temporomandibular joint to note any tension or areas of tenderness. Palpation should be performed both at rest and during phonation. Also palpate the thyroid and check for any lymphadenopathy. Inspect the ears and nose to ensure there is no obstruction. Respiratory examination may reveal stridor or wheezing or other findings suggestive of respiratory disease. A neurologic examination may reveal tremors, weakness, or other deficits that suggest neuromuscular disorders.
Laryngoscopy should be done promptly for prolonged dysphonia, respiratory compromise, or when risk factors, particularly smoking, are present. This may require prompt referral from the primary care provider to avoid delay in diagnosis of serious conditions. Empiric therapy of dysphonia with antibiotics, anti-reflux medications, corticosteroids, and speech therapy are not recommended prior to visualization of the larynx. See Table 1 for additional recommendations for dysphonia.
| Statement | Strength of Recommendation | Rationale |
|---|---|---|
| Recommendation | Dysphonia affects quality of life and may be a symptom of underlying disease. Patient’s reported symptoms, as well as proxies’ collateral input should be sought. |
| Recommendation | The history of dysphonia, inciting factors, medications, and other factors should be obtained. Physical examination should focus on voice quality, head and neck examination , and respiratory evaluation. |
| Strong Recommendation | Although most dysphonia is self-limiting, the presence of risk factors such as smoking may be associated with conditions having significant morbidity and mortality. Prompt laryngoscopy may improve quality of life and outcomes. |
| Option | This highlights the importance of visualizing the laryngeal tissues when dysphonia is present. |
| Recommendation | Viral causes are self-limited and typically last 1–3 wk. Dysphonia of longer duration warrants laryngoscopy for diagnostic purposes. |
| Recommendation Against | Causes of persistent dysphonia are often seen on laryngoscopy. This avoids the risks of radiation exposure with CT, side effects from MRI, and potential risks of contrast |
| Recommendation Against | Evidence for treating patients with dysphonia without reflux symptoms is inconclusive. Due to side effects of medications, and delay in treatment, visualization should be performed. |
| Recommendation Against | Except in limited cases, evidence does not support empiric therapy with corticosteroids, and medication has significant short- and long-term side effects. |
| Strong Recommendation Against | Most acute cases of dysphonia are caused by viruses. Bacterial infections should be confirmed prior to antibiotic therapy |
| Recommendation | Laryngoscopy is necessary to establish a diagnosis and to allow appropriate therapy |
| Strong Recommendation | Voice therapy is one of several treatments for dysphonia. Conditions such as muscle tension dysphonia, spasmodic dysphonia and Parkinson’s disease may particularly benefit. |
| Recommendation | While nonsurgical management is preferred, surgery is the preferred treatment for certain lesions of the vocal fold |
| Recommendation | Botulinum toxin is a preferred treatment for spasmodic dysphonia, in which increased laryngeal muscle tone causes dysphonia |
| Recommendation | Patient education about prevention and treatment of dysphonia should be offered to patients |
| Recommendation | The guideline emphasizes improving quality of care for patients with dysphonia. Patients should be followed until resolution of symptoms or appropriate diagnosis and management has been done. |
Related posts:
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
