Since the early 1980s, more recognition has been given to the multiple factors that can cause voice disorders. Whereas diagnosis was once fairly rudimentary, relying primarily on the ears and eyes of the physician, today a number of diagnostic techniques are available to augment the senses of the physician and have lead to a more accurate and complete diagnosis and subsequent improved treatment. Despite this improvement in diagnosis, finding the correct or full etiology of a voice disorder or vocal cord damage can be challenging. Increased recognition is needed of the variety of conditions, as well as side effects of some medications, that may lead to vocal cord damage.
May Be More than Misuse or Abuse of the Voice
Although the most frequent cause of voice disorders is misuse or abuse of the voice, it is important for physicians to consider other possible causes in their workup of a patient with symptoms of vocal cord damage. Some of the main conditions that can cause vocal damage include reflux laryngitis and vomiting with bulimia, said Peak Woo, MD, Professor in the Department of Otolaryngology at Mount Sinai School of Medicine in New York, as well as previous vocal fold injury from intubation and surgery. According to information on the Voice Foundation Web site (www.voicefoundation.org ), reflux laryngitis is one of the two most commonly overlooked or missed voice disorders, along with laryngeal paresis.
Reflux laryngitis is a condition caused by a backflow of stomach fluids into the voice box area, which produces irritation and swelling of the voice box. The acids and enzymes in the stomach fluids that flow back into the voice box can cause hoarseness, the need for frequent throat clearing, a sore throat, or cough, but usually do not cause heartburn. This condition may be associated with bulimia, where a person vomits frequently. However, according to Gayle Woodson, MD, Professor of Otolaryngology at Southern Illinois University School of Medicine in Springfield, Ill., unless the person aspirates while vomiting, the vomitus does not come in contact with the larynx. On the other hand, she said, people who can vomit at will generally have a greater incidence of acid reflux during the day and at night, and this is probably the single greatest cause of chronic laryngitis.
Although Dr. Woo thinks that vomiting with bulimia may be a condition associated with symptoms of vocal cord damage, he thinks it is not common. Vocal fold damage from bulimia is very unusual, he said.
Laryngeal paresis (or vocal fold paresis) is a condition in which a person loses partial or complete nerve functioning in the muscles of the voice box, which affects the ability to speak, sing, and sometimes breathe and swallow, and often leads to voice tiring after prolonged use. This condition can be mild to severe and is often missed as a cause of vocal cord damage.
According to information from the Voice Foundation, diagnosis of either one of these commonly missed causes of voice problems can be made by conducting a couple of key tests. Tests for reflux laryngitis begin with inspection of the voice box using a rigid or flexible laryngoscope, conducting a treatment trial to see if symptoms improve after the patient takes medications to reduce stomach fluid backflow, and, if necessary, doing a follow-up test to confirm abnormal levels of acid throughout the day by using a double-probe pH monitor. Tests for laryngeal paresis include identification of fold abnormalities by using a laryngoscope and confirming a diagnosis of vocal fold paresis by using laryngeal electromyography.
Effect of Medications
Another increasingly recognized potential cause of vocal cord damage is the use of certain medications, particularly those used to treat asthma. Several studies have shown the potential for some medications to damage the larynx. Krecicki and colleagues (Med Sci Monit 2006;12(8):CR351-4) recently reported on damage to the larynx among 50 patients with asthma treated with inhaled corticosteroids. Prior to their diagnosis of asthma, none of the patients reported any disorders or dysfunction of the larynx. After treatment, 20% of the patients developed vocal cord atrophy (VFA), 44% developed atrophy of laryngeal mucosa (ALM), and 20% developed vocal fold bowing (VFB). These numbers were significantly greater than those found in a control group of 41 patients, of whom 19.5% developed ALM (p = 0.006) and 2.4% developed VFB (p = 0.002), and 9.7% developed VFA (which showed a trend toward significance at 0.08).
Many medications do affect the voice, said Dr. Woodson. The worst medication is Advair [fluticasone propionate/salmeterol xinafoate], an asthma inhaler. Many patients get yeast infections of the larynx or white plaques, inflammation, and swelling, in the absence of any infection.
Agreeing that many medications can affect the voice, Clark A. Rosen, MD, Associate Professor in the Department of Otolaryngology at University of Pittsburgh Medical Center, emphasized that many of these effects do not cause permanent vocal cord damage. Yes, some asthma inhalers, especially Advair, can cause irritation or inflammation of the vocal cords, he said. However, once this has been identified and the Advair has been stopped, the patient’s voice typically recovers to completely normal. Thus, it is rare for medications to cause permanent damage to the vocal cords.
Although stopping or changing medication is recommended if the vocal cords are adversely affected, Jonathan E. Aviv, MD, Medical Director of the Voice and Swallowing Center at the College of Physicians and Surgeons, Columbia University Medical Center in New York, suggested that this may not be necessary. According to Dr. Aviv, the solution may not be to use the drugs differently, but to use them with an anti-acid medication such as proton pump inhibitors, such as [esomeprazole, omeprazole, or rabeprazole].
Increasing Recognition and Knowledge of the Causes of Vocal Cord Damage
According to the Voice Foundation, the need for recognizing that multiple factors may be contributing to voice problems is necessary to ensure appropriate treatment. A simple formula used on their Web site may help physicians improve diagnosis of these problems: Medical + Non-Medical + Compensatory Mechanisms = Voice Disorder.
According to information on the Voice Foundation’s Web site, Interacting causes may include medical causes, nonmedical causes, and patient behaviors that compensate for voice problems. All can contribute and aggravate the voice disorder. More importantly, if all contributing factors are not addressed in the treatment plan, treatment cannot be fully effective, even if it is partially correct.
A key challenge for otolaryngologists is to recognize that voice problems may have a cause, or multiple causes, not attributable or solely attributable to what once where considered standard causes, such as misuse/abuse of the voice or smoking. According to Dr. Woo, when a patient presents with voice problems that are not attributable to an ENT condition but nevertheless has damage, a careful search for medical conditions such as reflux laryngitis, medication-related laryngitis, and thyroid or endocrine conditions should be undertaken, adding that this can usually be done by otolaryngologists with appropriate referral to pulmonary and/or gastroenterology physicians as needed.
Dr. Rosen emphasized that along with a careful review of the medications a patient is using that may have negative effects on the voice, it is necessary to recognize possible psychological conditions that may be contributing to a voice disorder. Other non-ENT related areas to evaluate when patients present with voice disorders include psychological problems, which can present as voice conditions, he said. In this case, careful evaluation of the anatomy and physiology are warranted to rule out any otolaryngologic disorder effecting the voice, followed by an evaluation by a mental health professional preferably working with the voice team.
Overall, to improve diagnosis and thus treatment of vocal cord damage, otolaryngologists need to be better educated about its many potential causes. The concept of vocal fold scar and a related condition called sulcus vocalis is often under-recognized among otolaryngologists, most notably because it is thought to be a rare condition, said Dr. Rosen. This is in fact false.
Dr. Woo agreed. Often there is not a wide recognition among general otolaryngologists as to the causes for vocal cord damage, he said. However, with the increasing specialization of laryngologists, this can be diagnosed with ease. This is especially true now that more sophisticated endosopic equipment, including video stroboscopy, is now commonly used.
For Dr. Rosen, these specialized diagnostic tools are good for diagnosing vocal fold scar, but they are not used widely by most otolaryngologists. Without the ability to watch the vocal cords vibrate using laryngovideostroboscopy, vocal fold scar and sulcus vocalis are often a misdiagnosis, he said. Thus, patients continue to suffer from significant voice conditions without adequate diagnosis that would lead to prompt and appropriate treatment.
The potential causes of vocal cord damage are numerous. Recognition and knowledge of the many causes of vocal cord damage is critical to improving diagnosis and to ultimately provide the best and most accurate treatment.
©2007 The Triological Society