Voice disorders may be caused by many different factors, events, physical ailments and diseases. The vast majority of voice problems are caused by factors that are not life-threatening and that are easily treatable.
Almost every disorder of the larynx may result in more than one symptom, and there is no single symptom associated with a specific disorder of the larynx. For example, hoarseness, limitations in pitch and loudness, shortness of breath or increased vocal effort may be a sign of any number of disorders of the larynx.
The severity of the voice symptoms does not necessarily correspond to the severity of the underlying disease. The only way to know what is causing your specific voice problem is to be evaluated by a laryngologist .
A common cause of voice problems is one or more benign (non-cancerous) lesions on the vocal fold. A lesion is a structural defect -- an irregular or abnormal area of tissue -- that can easily disrupt the normal functioning of the vocal folds and result in symptoms of a voice disorder. Frequently, the lesion forms a protruding bump. These are called "discrete" lesions because they can be seen to occupy a limited area of the vocal fold with relatively clearly-defined borders, as opposed to generalized ("diffuse") irritation of a larger area of the vocal fold.
During voice production, the right and left vocal fold vibrate (opening and closing against each other) to produce sound. The middle portion of the edges of the vocal folds collide together first and hardest, and whip up out of the air stream with the greatest force (similar to the middle portion of a jump rope that hits the ground first and hardest with each repeated swing and moves in the widest arc). Therefore, this mid-area of the tissue is most susceptible to irritation. That is why many of these protruding lesions often form at the edge, or vibratory margin, of the vocal fold in the middle of the vibrating vocal fold.
A lesion can form on both the right and the left vocal fold at the same time. When this happens, they look like mirror images of each other. At other times, a lesion will form at the mid-portion of one vocal fold, and then over time, irritate the opposite area on the other vocal fold during each cycle of vibration. This second lesion is called a "reactive" lesion, because it forms in reaction to the irritation of the first lesion. When this happens, the lesions do not look symmetrical. One lesion may be larger and more firm-appearing than the other. There can be a "cup and saucer" appearance to the two lesions: the protruding lesion produces a small indentation in the reactive lesion.
Discrete benign mucosal lesions are not painful. However, they can result in a less efficient voice production system, so that it takes more effort to speak. This can cause a sense of fatigue and even neck discomfort. The lesions can cause many undesirable voice changes. In an effort to clear and improve the sound of the voice, an individual may use the muscles of the throat and neck. This can increase the throat and neck discomfort.
Vocal fold mucosal lesions do not hurt and only rarely can they be "felt." However, when irregularities form on the surface of the vocal folds, the mucous often gets stuck and accumulates on the lesion. The thickened mucous can make a person feel like there is "something" in the throat, and the natural reaction is to cough or clear the voice. Unfortunately, frequent coughing and throat-clearing only contribute to the mucosal irritation and can make the lesions (and voice problem) worse. Learning how to use "safe" vocal behaviors in place of coughing and throat clearing is part of the voice therapy program.
The most common cause of discrete benign mucosal lesions is prolonged and repeated irritation (micro-trauma) to the surface tissues of the vocal folds. The source of the irritation may be excessive vocal demands ("vocal abuse"), gastric reflux, repeated upper respiratory infections, or certain medications, for example. Often, there is more than one cause, with one predominant factor and a number of lesser, contributing factors.
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Based upon the latest research, how we think about discrete benign mucosal lesions is changing. It used to be that these lesions were always identified as one of three types – nodules, polyp or cyst. And it used to be that treatment for nodules was always voice therapy, and treatment for a polyp or a cyst was always surgery. It now appears that sometimes these "bumps" have characteristics of more than one type of lesion, and it is not always possible to distinguish between different benign mucosal lesions during an office examination. The best treatment depends upon a number of factors specific to the individual patient. Make sure that you are getting the most current diagnosis and treatment information for your voice problem.
Nodules are thickening of the middle of the vocal folds. They always occur in pairs—one on each vocal fold – and they are fairly symmetric, or similar in shape and size. Nodules are usually caused by excessive vocal demands, or improper speaking or singing techniques. It is commonly believed that when the nodules first begin to form, nodules are usually soft with a wide base. With time, they may become more firm, similar to calluses. Nodules usually form slowly over time. Nodules cause incomplete contact of the vocal folds, resulting in breathiness, decreased loudness, and vocal fatigue. The nodules can also cause irregular vocal fold vibration, resulting in hoarseness and pitch breaks.
Treatment for nodules is usually a course of voice therapy. Infrequently, surgery is required if the voice therapy does not provide adequate symptom relief for the patient.
NODULES - The nodules prevent the vocal folds from closing completely during phonation
NODULES - Sometimes nodules can become firm, as these are that protrude from the mid-portion of each vocal fold.
NODULES - Often, nodules in the early stages of formation are soft, as these are that protrude from the mid-portion of each vocal fold.
Polyps can occur singly or in pairs. Usually, a polyp forms mid-way along the free margin of the vocal fold. Sometimes, a smaller lesion forms on the opposite vocal fold in reaction to the polyp, where the tissue gets irritated by the initial polyp hitting against it during each cycle of vibration. Unlike nodules which usually form slowly over time from repeated and prolonged irritation, a polyp can sometimes form as a result of an isolated traumatic occurrence, such as coughing violently or screaming at a sporting event.
Treatment for a polyp usually begins with voice therapy, often accompanied by voice rest, a significant (but temporary!) reduction in voice use. Sometimes, surgery is necessary in order to provide the patient with the best voice outcome.
POLYP - The vocal fold on the left side of the picture has a firm-appearing polyp, which has caused irritation of the mucosa on the opposite vocal fold.
POLYP - The polyp that protrudes from the vocal fold on the left has a blood supply, making it appear red.
POLYP - The polyp prevents the vocal folds from closing during phonation.
Cysts are benign lesions that can occur singly or in pairs. A cyst is a collection of fluid in a sac-like structure. Cysts may be caused by a small gland in the vocal fold that does not drain well, and so it accumulates mucous. It is unknown whether vocal fold irritation or excessive voice use contributes to the formation of cysts.
Unlike nodules, cysts may not respond well to voice therapy alone. Depending upon the needs of the patient and the nature of the cyst, an abbreviated course of voice therapy may be recommended to determine whether surgery is necessary. For other types of cysts, surgical removal of the lesion is recommended, followed by a period of voice rest, a significant (but temporary!) reduction in voice use, and then voice therapy.
CYST - The vocal fold on the right side of the picture has a firm cyst.
CYST - The vocal fold on the left side of the picture has a cyst, causing the mucosal cover to bulge outward
CYST - The vocal fold on the left side of the picture has a large cyst which has caused irritation of the mucosa on the opposite vocal fold.
CYST - The vocal fold on the left side of the picture has a clearly-defined cyst which causes the vocal fold to bulge outwardly, impairing phonatory glottal closure and mucosal wave vibration.
Also called "contact ulcers", granulomas are discrete (clearly-defined) lesions that occur on the back portion of the vocal fold where it attaches to the arytenoid cartilage. Laryngopharyngeal reflux (LPR) is the most common cause of formation of a granuloma. Another common cause is irritation from an endotracheal tube (the tube placed in the throat for breathing during a surgery under general anesthesia), which can rub against the back of the larynx.
Treatment for granuloma depends upon the size of the lesion and the length of time it has been present, but most likely will require control of reflux, and may also include relative voice rest, and/or surgery and voice therapy. Surgery by itself, without other measures, will often result in the regrowth of the lesion in a short period of time.
GRANULOMA - The vocal fold on the right side of the picture has a granuloma attached to the vocal process (top of picture).
GRANULOMA - The posterior vocal process on the left side of this picture has a large granuloma, which causes painful phonation and swallowing for this patient.
GRANULOMA - The granuloma seen on the left side of this photo is causing a small reactive lesion on the opposite vocal process.
Acid reflux may be a primary cause of or a contributing factor to voice problems. Many people have heard of acid reflux disease. When the refluxing of stomach acid primarily affects the esophagus, it is termed gastroesophageal reflux disease (GERD). When the refluxing affects primarily the voice production system – the larynx and pharynx – it is called laryngopharyngeal reflux disease (LPR). It may also be called "reflux laryngitis".
When normal, healthy individuals eat or drink, swallowing propels food and liquid from the back of the mouth down into the esophagus, the tube connecting the mouth to the stomach. Two esophageal sphincters, or valves, open and close in such a way as to promote passage of food into the stomach and prevent backflow.
GERD, or "classic" reflux, occurs when the acid contents move from the stomach backwards up the esophagus, due either to improper functioning of one or both sphincters (which can be aggravated by a condition known as "hiatal hernia") or due to muscular spasms of the esophagus.
LPR occurs when refluxed stomach contents reach all the way up into the throat. Almost everyone experiences reflux occasionally. When acid reflux occurs often, however, the larynx can become irritated, because the larynx and back of the throat do not have the same type of lining as the esophagus to protect from acidic fluids. Sometimes, if the LPR is severe enough, it can cause a non-cancerous lesion (growth) on the back of the vocal fold, called a granuloma.
Symptoms of LPR can include: a choking sensation, sometimes severe enough to wake a person up at night; sore throat; voice changes; a sensation of something caught in the throat; frequent coughing and throat clearing; and a sour or bitter taste in the mouth, especially upon rising in the morning. The "classic" symptoms of heartburn, burping or chest pressure are associated with GERD, but not necessarily with LPR.
Many patients with voice problems caused by LPR are not even aware that they have acid reflux problems. Because of the many bothersome symptoms of LPR, this condition can create habits which further contribute to the voice problem, such as constant throat-clearing or using excessive muscle tension when speaking.
LPR is treated primarily in two ways. Making some simple lifestyle, or behavioral changes can help prevent or decrease LPR and improve the voice. Take a look at our LPR Precautions Tips (PDF) for some helpful suggestions. In conjunction with lifestyle changes, medications can also be used to help control LPR. Behavioral changes should always accompany medication regimens to help the medication work most effectively. In many instances, it can take a few months of regular medication use before the LPR symptoms are significantly reduced.
There are many medications, some over-the-counter and some requiring a prescription. The amount of medication taken, and the time of day it is used, can significantly influence its effectiveness. If you think you have reflux laryngitis, see an otolaryngologist (ear, nose and throat physician) who is experienced in treating voice disorders.
Laryngopharyngeal Reflux: LPR has caused inflammation (redness and swelling) of the back of the larynx. The vocal fold mucosa is irritated and copious thick secretions cover the vocal folds. This causes discomfort and irregular mucosal wave vibration, leading to voice changes.
Many people use the term "laryngitis" to mean voice change, or hoarseness. Laryngitis is actually an inflammation (irritation and swelling) of the larynx, usually caused by some other disorder, such as Laryngopharyngeal reflux (LPR), infection, smoking, or inhaling noxious fumes.
Laryngitis may be acute (short-term) or chronic (long-term). Treatment depends upon the type of laryngitis and its cause. Bacterial infections are generally treated with antibiotics. However, antibiotics are not helpful for viral infections. Antibiotics taken for another, not necessarily related reason, may actually cause fungal infections.
Inhalers, taken for asthma or other lung disease, can have this same effect, or even cause irritation from the substances in the inhaler. Laryngitis is not a single disease, but rather a word that describes an irritated, swollen larynx. It is up to your doctor to determine the cause.
Any "laryngitis" that lasts beyond two weeks, or fails to improve with antibiotics, should be evaluated by a physician, preferably one who can make a complete examination of the larynx and vocal folds.
INFLAMMATION - Inflammation causes both of these vocal folds to be swollen, resulting in limited mucosal wave vibration and incomplete glottal closure.
A common cause of voice problems is abnormal patterns of muscle activation, referred to by many names, including muscle misuse dysphonia, vocal hyperfunction, or muscle tension dysphonia (MTD). To understand MTD, we must remember that voice production requires rapid and precise coordination of many muscles.
The degree of muscle contraction ("tension" setting), the timing of the contraction and the coordination of that activity with the simultaneous contraction of many other muscles, is an intricate and ever-changeable process that must be balanced with regulation of changing airflows and air pressures.
This balance of aerodynamic and muscle forces must adapt to rapidly changing speech requirements, including modulations of pitch, loudness, and rate, that are a component of all speech contexts. When an imbalance of muscle activity occurs during phonation, the result can be a range of symptoms from vocal fatigue, neck discomfort, altered vocal quality, to complete loss of voice.
There are many theories about the nature and causes of MTD, but little is known for certain, and MTD may vary among individuals. One theory is that the underlying mechanism of MTD is incomplete relaxation of the posterior cricoarytenoid muscle, the muscle responsible for opening the vocal folds. This may result in incomplete opening of the vocal folds during each vibratory cycle of phonation, which in turn causes the thyroarytenoid muscle (the body of the vocal folds) to over-contract in compensation.
Other theories describe the nature of MTD as excessive contraction of groups of intrinsic laryngeal muscles (the muscles of the vocal folds and those that connect the vocal folds and cartilages) and extrinsic laryngeal muscles (the muscles that connect parts of the larynx to other structures). Still another theory describes MTD as in-coordination of laryngeal muscle contraction with breathing, especially the amount of air pressure and the timing of the airflow.
It is unclear whether MTD represents a disorder primarily of incoordination (mis-timing) of muscles, or excessive muscle contraction. In either case, it can result in impaired vocal fold vibration and the sensation of extra effort when talking. Our inability to accurately measure the timing or force of laryngeal muscle contractions within a clinical setting contributes to our lack of clear understanding of this voice disorder.
MTD - The vocal tract above the true vocal folds in constricted, making it difficult to produce voice.
The cause of muscle tension dysphonia is not known. We hypothesize that it may be caused by the body’s voice production system reacting to environmental (external) or systemic (internal) irritants. Common irritants include upper respiratory infection, second-hand smoke, laryngopharyngeal reflux (LPR), significant vocal demands, or stressful life events. Most often, it is likely more than one single factor. But truthfully, we do not yet understand why some people are susceptible to MTD and others are not.
MTD is sometimes categorized as either primary or secondary. In primary MTD, there is no clear or predominant organic cause (that is, no detectable abnormality of the structures or functioning of the larynx other than the MTD). Historically, MTD was called "functional" dysphonia, because the cause was unknown. However, that term often implied that there was no "real" reason for the problem and it was assumed to be a psychosomatic disorder. Although psychological factors may certainly contribute to MTD, we no longer feel it is primarily a psychosomatic problem.
In some cases of primary MTD, the factor which initially caused the abnormal muscle patterns (the precipitating cause) is no longer present, but the aberrant muscle behaviors have become a habit. We think this may occur, for example, in cases of upper respiratory infection, especially in speakers with significant vocal demands, such as teachers. In secondary MTD, the abnormal patterns of muscle activation are secondary to (a result of) another underlying disorder, such as vocal fold atrophy, or a benign lesion.
We think that, in an attempt to compensate for the vocal changes, an individual alters muscle activation patterns, possibly by using excessive muscle tension or recruiting the use of muscle not ordinarily active. This process is referred to as "maladaptive compensatory behaviors", and they can become a habit over time. In either primary or secondary MTD, the habitual use of abnormal patterns of muscle activation during phonation can be difficult to unlock without treatment.
The most common treatment for MTD is voice therapy. There are a number of different therapeutic regimens that improve voice production, including resonant voice techniques and digital laryngeal massage. Sometimes, the therapy program is intensive for the first week or two (up to three or four session in a week) and then quickly tapers off to once a week and then less frequently.
Although we have no research studies that prove the effectiveness of voice therapy for MTD, our clinical experience suggests that voice therapy is quite helpful, even in severe cases in which a person has almost no voice at all. Uncommonly, Botulinum toxin A ("botox") injections are used in conjunction with voice therapy. to release the abnormal muscle activation patterns.
Reinke’s edema is an enlargement of the upper layer of covering of the vocal fold (called Reinke’s space, after the man who first described this layer). The most common cause of Reinke’s edema is smoking. In fact, the condition is almost never seen in nonsmokers. The typical enlargement is caused by an accumulation of gelatinous fluid. Sometimes, Reinke’s edema is mistakenly identified as ‘swollen’ vocal folds. The old term for these lesions is "polyp", but now we know that Reinke’s edema (also called polypoid corditis, just to confuse you) and vocal fold polyps are not the same.
REINKE'S EDEMA - The swelling of the vocal fold mucosa is caused by smoking.
The swollen vocal fold covering vibrates more slowly than normal vocal folds, resulting in raspiness and significantly lowered vocal pitch. For this reason, women more frequently notice the symptoms than men, who already have a low-pitched voice. The swelling can get so large that it can partially block the airway, causing a sensation of shortness of breath.
Often, patients diagnosed with Reinke’s edema are concerned about the risk of cancer, since both are caused by smoking. Rarely is Reinke’s edema found to be malignant (cancerous). However, the presence of Reinke’s edema should be considered your body’s "warning signal" to stop smoking immediately. Cessation of smoking is essential in the treatment for Reinke’s edema. Without this, the swelling almost always returns after surgery. Sometimes, the cessation of smoking alone will improve a mild case of edema to the point that surgery is not necessary.
The tissue that covers the vocal folds can turn into cancer. By far the most common cause of this is smoking. Just as the noxious chemicals in cigarette and cigar smoke irritate the lungs and cause lung cancer, they also affect the delicate covering of the larynx. After all, the smoke must go through the vocal folds to get to the lungs.
Hoarseness is the main sign of cancer of the vocal folds. The cancer cells form a mass that interferes with the closure of the vocal folds of vocal fold vibration and thus results in a hoarse voice. If it’s ignored, the cancer grows into deeper tissues, causing progressively more damage to the larynx. It may result in a vocal fold paralysis, or get so large that it causes breathing difficulty. If allowed to grow unchecked, it can extend outside of the larynx and even into distant parts of the body. That’s why hoarseness in a smoker that lasts more than a week or two should never be ignored. Caught early, vocal fold cancer may be curable without radical surgery. Allowed to grow, it can be deadly.
Cancer in the rest of the larynx, outside of the vocal folds, may grow to considerable size without causing any voice disturbance. Symptoms may include shortness of breath, cough that produces blood in the spit, a sensation of a mass or unexplained pain. A lump in the neck may be the first sign of trouble. Smokers should not hesitate to see a physician if they experience unexplained symptoms.
Treatment may include surgery, radiation or chemotherapy (medical therapy), each used alone or in combination with the others. The chances of cure depend on the size and extent of the lesion when it is discovered. Cancer of the larynx no longer automatically requires a laryngectomy (surgical removal of the larynx) for treatment, if caught early.
Of course, the safest way to deal with cancer is to minimize your chances of getting it in the first place. And that means stop smoking – now.
A scar of the vocal fold is not quite the same thing as a scar elsewhere in the body. In voice production, the mucosa, or covering of the vocal fold, must vibrate over the underlying tissue. Underneath the mucosa is a special tissue layer, called Reinke’s layer, or the superficial lamina propria, that permits this. You can think of this as a ball-bearing layer that allows the free motion of overlying mucosa, while keeping it attached to the underlying muscle.
Any disruption of this layer is called a vocal fold scar. Scarring means that the mucosa is tethered to the underlying tissue and cannot vibrate freely. The resulting irregularities in vibration cause hoarseness, breathiness and demand increased effort to produce voice.
SULCUS - The sulcus on each vocal fold causes the mucosal cover to adhere to the deeper layers of tissue, resulting in poor mucosal wave vibration and incomplete glottal closure.
SULCUS - The sulcus on each vocal fold can be seen as a ridge running the length of the folds.
Scar can occur in many ways. It can result from vocal fold lesions that have been present for a long time and grown into deeper tissue. It can result from generalized inflammation of the vocal folds, like a vocal fold hemorrhage or radiation used to treat cancer. It can also be an unintended consequence of surgery on the vocal folds. To a certain extent, scarring is unpredictable – it can happen even after the most meticulous surgery. But there are measures to take to minimize scar – voice rest after surgery, controlling laryngopharyngeal reflux (LPR), not irritating the vocal folds with cigarette smoke. The use of the laser for vocal fold surgery is another factor that may affect scar formation, because of the heat radiated by the laser beam. Prior to undergoing any vocal fold surgery, it’s important to speak to your surgeon about all of these factors, and especially about the use of the laser.
Sulcus vocalis is a special case of scarring in which the superficial lamina propria (or "ball-bearing layer") is absent over the length of the vocal fold. The reason for this is unclear. Theories include a genetic or developmental cause. There appears to be a higher incidence in certain ethnic groups.
Repairing scar once it has already happened is challenging. Simply separating the mucosa from the underlying tissue almost always results in the re-adhesion because the superficial lamina propria is still missing. There is no adequate replacement for the superficial lamina propria, although many substances have been tried. Synthetic tissue is under development, but not ready for clinical use. Substances that inhibit scar formation in other tissues exist, but their use in the vocal fold is experimental.
Voice therapy may make significant improvements in the voice of people with vocal cord scar, and especially in people with sulcus.