- What Is It?
Swallowing problems (dysphagia) definition and facts
- Dysphagia means difficulty swallowing.
- Swallowing is a complex action involving the muscles and nerves within the pharynx and esophagus, a swallowing center in the brain, and nerves that connect the pharynx and esophagus to the swallowing center.
- Dysphagia should be differentiated from odynophagia and globus sensation.
- General causes of dysphagia can be grouped as either oropharyngeal or esophageal. Specific causes include physical obstruction of the pharynx or esophagus, diseases of the brain, diseases of the smooth muscle of the esophagus, diseases of the skeletal muscle of the pharynx, and miscellaneous diseases.
- Symptoms of dysphagia may be swallowing-related or non-swallowing-related.
- The differential diagnosis of dysphagia includes odynophagia and globus sensation, tracheo-esophageal fistula, rumination syndrome, gastroesophageal reflux disease (GERD), and heart disease.
- Evaluation and diagnosis of the cause of dysphagia include history, physical examination, endoscopy, X-rays, esophageal manometry, esophageal impedance, esophageal acid testing, and tests for the diagnosis of muscular dystrophy and metabolic myopathies.
- The treatment of dysphagia depends primarily on its cause.
- Newer diagnostic procedures for the evaluation and diagnosis of the cause of dysphagia include high resolution or 3D manometry and endoscopic ultrasonography.
What is dysphagia?
Dysphagia is the medical term for the symptom of difficulty swallowing, derived from the Latin and Greek words meaning difficulty eating.
Mechanism of swallowing
Swallowing is a complex action.
- Food is first chewed well in the mouth and mixed with saliva.
- The tongue then propels the chewed food into the throat (pharynx).
- The soft palate elevates to prevent the food from entering the posterior end of the nasal passages, and the upper pharynx contracts, pushing the food (referred to as a bolus) into the lower pharynx. At the same time, the voice box (larynx) is pulled upwards by muscles in the neck, and, as a result, the epiglottis bends downwards. This dual action closes off the opening to the larynx and windpipe (trachea) and prevents passing food from entering the larynx and trachea.
- The contraction of the muscular pharynx continues as a progressing, circumferential wave into the lower pharynx pushing the food along.
- A ring of muscle that encircles the upper end of the esophagus, known as the upper esophageal sphincter, relaxes, allowing the wave of contraction to push the food from the lower pharynx on into the esophagus. (When there is no swallow effort, the muscle of the upper sphincter is continuously contracted, closing off the esophagus from the pharynx and preventing anything within the esophagus from regurgitating back up into the pharynx.)
- The wave of contraction, referred to as a peristaltic wave, progresses from the pharynx down the entire length of the esophagus.
- Shortly after the bolus enters the upper esophagus, a specialized ring of muscle encircling the lower end of the esophagus where it meets the stomach, known as the lower esophageal sphincter, relaxes so that when the bolus arrives it can pass on into the stomach. (When there is no swallow the muscle of the lower sphincter is continuously contracted, closing off the esophagus from the stomach and preventing contents of the stomach from regurgitating back up into the esophagus.)
- After the bolus passes, the lower sphincter tightens again to prevent contents of the stomach from regurgitating back up into the esophagus. It remains tight until the next bolus comes along.
Considering its complexity, it is no wonder that swallowing, beginning with the contraction of the upper pharynx, has been "automated," meaning that no thought is required for swallowing once swallowing is initiated. Swallowing is controlled by automatic reflexes that involve nerves within the pharynx and esophagus as well as a swallowing center in the brain that is connected to the pharynx and esophagus by nerves. (A reflex is a mechanism that is used to control many organs. Reflexes require nerves within an organ such as the esophagus to sense what is happening in that organ and to send the information to other nerves in the wall of the organ or outside the organ. The information is processed in these other nerves, and appropriate responses to conditions in the organ are determined. Then, still other nerves send messages from the processing nerves back to the organ to control the function of the organ, for example, the contraction of the muscles of the organ. In the case of swallowing, processing of reflexes primarily occurs in nerves within the wall of the pharynx and esophagus as well as the brain.)
The complexity of swallowing also explains why there are so many causes of dysphagia. Problems can occur with:
- the conscious initiation of swallowing,
- propulsion of food into the pharynx,
- closing of the nasal passages or larynx,
- opening of the upper or lower esophageal sphincters,
- physical blockage to the passage of food, and
- transit of the bolus by peristalsis through the body of the esophagus.
The problems may lie within the pharynx or esophagus, for example, with the physical narrowing of the pharynx or esophagus. Dysphagia also may be due to diseases of the muscles or the nerves that control the muscles of the pharynx and esophagus or damage to the swallowing center in the brain. Finally, the pharynx and the upper third of the esophagus contain muscle that is the same as the muscles that we use voluntarily (such as our arm muscles) called skeletal muscle. The lower two-thirds of the esophagus is composed of a different type of muscle known as smooth muscle. Thus, diseases that affect primarily skeletal muscle or smooth muscle in the body can affect the pharynx and esophagus, adding additional possibilities to the causes of dysphagia.
Odynophagia and globus sensation
There are two symptoms that are often thought of as problems with swallowing (dysphagia) that probably are not. These symptoms are odynophagia and globus sensation.
Odynophagia means painful swallowing. Sometimes it is not easy for individuals to distinguish between odynophagia and dysphagia. For example, food that sticks in the esophagus often is painful. Is this dysphagia or odynophagia or both? Technically it is dysphagia, but individuals may describe it as painful swallowing (i.e., odynophagia). Moreover, patients with gastroesophageal reflux disease (GERD) may describe dysphagia when what they really have is odynophagia. The pain that they feel after swallowing resolves when the inflammation of GERD is treated and disappears and is presumably due to pain caused by food passing through the inflamed portion of the esophagus.
Odynophagia also may occur with other conditions associated with inflammation of the esophagus, for example, viral and fungal infections. It is important to distinguish between dysphagia and odynophagia because the causes of each may be quite different.
A globus sensation refers to a sensation that there is a lump in the throat. The lump may be present continuously or only when swallowing. The causes of a globus sensation are varied, and frequently no cause is found. Globus sensation has been attributed variously to abnormal function of the nerves or muscles of the pharynx and GERD. The globus sensation usually is described clearly by individuals and infrequently causes confusion with true dysphagia.
What causes swollowing problems?
As discussed previously, there are many causes of dysphagia. For convenience, causes of dysphagia can be classified into two groups;
- oropharyngeal (meaning that the cause is a problem in the mouth or pharynx) and
Causes also can be classified differently into several groups.
Physical obstruction of the pharynx or esophagus
- Benign and malignant tumors of the pharynx and esophagus. Most commonly these tumors are malignant.
- Tumors of the tissues surrounding the pharynx and esophagus. These tumors can compress the pharynx and esophagus leading to obstruction. This is an unusual cause of dysphagia. An example would be thyroid cancer.
- Narrowing (strictures) of the esophagus. The strictures usually are due to GERD and are located in the lower esophagus. These strictures are the result of ulcerations of the esophagus that heal, with scarring as a result. Less common causes of strictures include ingestion of acid or lye during attempts at suicide, some pill medications that may stick in the esophagus and cause ulceration and scarring, for example,potassium chloride ( K-Dur, K-Lor, K-Tab, Kaon CL, Klorvess, Slow-K, Ten-K, Klotrix, K-Lyte CL), doxycycline (Vibramycin, Oracea, Adoxa, Atridox and others),quinidine (Quinidine Gluconate, Quinidine Sulfate), biphosphonates used for treating osteoporosis), radiation therapy, and infections of the lower esophagus, particularly in people with AIDS.
- Schatzki's rings. These rings are benign, very short narrowings (millimeters in size) at the lower end of the esophagus. The cause of Schatzki's rings is unknown though some physicians believe they are caused by GERD.
- Infiltrating diseases of the esophagus. The most common infiltrative disease is a disease in which the wall of the esophagus fills with eosinophils, a type of white blood cell involved in inflammation. This disease is called eosinophilic esophagitis. The wall of the esophagus becomes stiff and cannot stretch as the bolus of food passes. As a result, the bolus sticks.
- Diverticuli (outpouchings) of the pharynx or esophagus. The diverticuli can expand when it fills with swallowed food and can compress the pharynx or esophagus. The diverticuli can be at the upper end of the esophagus (Zenker's diverticulum) or, less commonly, at the middle or lower end of the esophagus.
- Cricopharyngeal bars. These bars represent a part of the upper esophageal sphincter that has hypertrophied, that is, expanded. The bar does not stretch normally as the bolus passes. The cause of cricopharyngeal bars is unclear. Small bars that do not interfere with swallowing are quite common.
- Cervical osteophytes. Rarely, arthritis of the neck results in an overgrowth of bone that extends anteriorly out from a vertebra (an osteophyte). Since the vertebrae of the neck lie immediately behind the lower pharynx and uppermost esophagus, the osteophyte may impinge on the pharynx and esophagus.
- Congenital abnormalities of the esophagus. These abnormalities are present from birth and are almost always discovered in infants because of problems when oral feeding begins.
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Diseases of the brain
- Stroke. The most common disease affecting swallowing is a stroke (cerebrovascular accidents) that affect the swallowing center.
- Tumors of the brainstem. These tumors interfere with the transmission of nerves that carry information between the esophagus and the swallowing center in the brain.
- Degenerative diseases of the brain. The three most common degenerative diseases are Parkinson's disease, multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS).
- Degenerative diseases of the motor nerves. Motor nerves are nerves that control the contraction of skeletal muscle. Poliomyelitis (polio, caused by a virus) is an example of a degenerative disease of motor nerves in the brain that impairs swallowing by interfering with the control of skeletal muscle in the pharynx.
Diseases of the smooth muscle of the esophagus
- Achalasia. Achalasia is a condition that affects the smooth muscle portion of the esophagus, that is, the lower esophagus and the lower esophageal sphincter. Specifically, the peristaltic wave disappears, and the lower sphincter does not relax. As a result of this "double whammy," the food bolus sticks in the esophagus. With prolonged obstruction the esophagus enlarges (dilates) causing additional problems. The cause of achalasia is not clear but probably involves abnormalities of the nerves within the smooth muscle that lead to abnormal function of the muscle. In one sense, therefore, achalasia may be considered primarily a neurological problem. There is a parasitic infectious disease, called Chagas disease that mimics achalasia and occurs with a higher prevalence among individuals from Central and South America. In Chagas disease, the parasite appears to destroy the nerves that control the smooth muscle.
- Ineffective peristalsis. Ineffective peristalsis is not really a disease but rather a condition in which the force of the peristaltic wave of contraction is reduced to the point that the wave no longer is strong enough to push the bolus of food through the esophagus and into the stomach. By itself, ineffective peristalsis usually does not cause a serious problem. The reason for this is that almost all meals are eaten in the upright position, and the effect of gravity on the bolus provides an additional and important force that alone can propel most boluses into the stomach. Severe problems only occur when a second impediment to passage of the bolus occurs such as a stricture of the esophagus. Ineffective peristalsis usually occurs by itself but it may be associated with other diseases such as collagen-vascular diseases (for example, scleroderma) and diabetes. Theoretically, ineffective peristalsis could be due to either muscular or neurological problems within the smooth muscle.
- Spastic motility disorders. Spastic motility disorders are a group of conditions of unknown cause in which contractions of the esophagus are not orderly. Rather than a progressing, peristaltic wave, contraction of all or a large portion of the esophagus is simultaneous (spastic), and thus the bolus of food is not propelled forward. Other disorders that are classified with the spastic disorders include peristaltic pressures that are abnormally high and spontaneous contractions of the esophagus, that is, contractions that are not triggered by a swallow. In addition to dysphagia, the spastic motility disorders may cause severe chest pain mimicking heart pain (angina) that occurs spontaneously, that is, unassociated with eating. The most common spastic disorder is referred to as "nutcracker" esophagus, a term that emphasizes the appearance of the esophagus on X-rays that is due to very high peristaltic pressures rather than spasm. The second most common spastic disorder is diffuse esophageal spasm, a name that emphasizes the spasm.
Diseases of skeletal muscle of the pharynx
- Polymyositis. Polymyositis is a disease of unknown cause in which skeletal muscle becomes inflamed and degenerates. It can affect skeletal muscle of the body as well as the pharynx.
- Myasthenia gravis. Myasthenia gravis is a disease in which there is abnormal transmission of signals between motor nerves and the skeletal muscles they control. The skeletal muscle of the pharynx may be affected.
- Muscular dystrophies. The muscular dystrophies are a group of inherited (genetic) diseases that are caused by the production of abnormal proteins in skeletal muscle cells. The abnormal proteins result in degeneration of the muscle cells and their replacement with scar tissue or fat. The primary symptoms of the muscular dystrophies are muscle weakness and spasm. Examples of muscular dystrophies include myotonic dystrophy, Duchenne's muscular dystrophy, and Becker's muscular dystrophy.
- Metabolic myopathies. Metabolic myopathies are a group of rare, inherited (genetic) diseases that are caused by a deficiency in activity of the enzymes in skeletal muscle cells that are important for generating the energy that is necessary for contraction of the muscle. The most common symptom of the metabolic myopathies is easy tiring of muscles and muscle cramps.
- Reduced saliva. Saliva facilitates swallowing by acting as lubrication for the bolus. Some medications, diseases (for example, Sjogren's syndrome), and radiation therapy to the head and neck that affects the salivary glands, all reduce the production of saliva, and can cause dysphagia, though usually it is mild.
- Alzheimer's disease
With neurological problems, there may be difficulty initiating a swallow because the bolus cannot be propelled by the tongue into the throat. Elderly individuals with dentures may not chew their food well and therefore swallow large pieces of solid food that get stuck. (Nevertheless, this usually occurs when there is an additional problem within the pharynx or esophagus such as a stricture.)
The most common swallowing symptom of dysphagia, however, is the sensation that swallowed food is sticking, either in the lower neck or the chest. If food sticks in the throat, there may be coughing or choking with expectoration of the swallowed food. If food enters the larynx, more severe coughing and choking will be provoked. If the soft palate is not working and doesn't properly seal off the nasal passages, food—particularly liquids--can regurgitate into the nose with the swallow. Sometimes, food may come back up into the mouth immediately after being swallowed.
Food that sticks in the esophagus may remain there for prolonged periods of time. This may create a sensation of the chest filling up as more food is eaten and result in an individual having to stop eating and possibly drinking liquids in an attempt to wash the food down. The inability to eat larger amounts of food may lead to loss of weight. In addition, the food that remains in the esophagus may regurgitate from the esophagus at night while the individual is sleeping, and the individual might be awakened by coughing or choking in the middle of the night that is provoked by the regurgitating food. If food enters the larynx, trachea, and/or lungs, it may provoke episodes of asthma and even lead to infection of the lungs and aspiration pneumonia. Recurrent pneumonia can lead to serious, permanent, and progressive injury to the lungs. Occasionally, individuals are not awakened from sleep by the regurgitating food but awaken in the morning to find regurgitated food on their pillow.
Individuals who retain food in their esophagus may complain of heartburn-like (GERD) symptoms. Their symptoms may indeed be due to GERD but are more likely due to the retained food and do not respond well to treatment for GERD.
With the spastic motility disorders, individuals may develop episodes of chest pain that may be so severe as to mimic a heart attack and cause the individuals to go to the emergency room. The cause of the pain with the spastic esophageal disorders is unclear although the leading theory is that it is due to spasm of the esophageal muscles.
How causes swallowing problems?
Odynophagia and globus sensation. The occasional difficulty in distinguishing dysphagia from odynophagia already has been discussed, as well as the difference between dysphagia and a globus sensation.
Tracheo-esophageal fistula. One disorder that can be confused with dysphagia is a tracheo-esophageal fistula. A tracheo-esophageal fistula is open communication between the esophagus and the trachea that often develops due to cancers of the esophagus but which may also occur as a congenital (inborn) birth defect. Swallowed food may provoke coughing that mimics the coughing due to dysfunction of the muscles of the pharynx that allows food to enter the larynx; however, in the case of a fistula, the coughing is due to the passage of food from the esophagus through the fistula and into the trachea.
Rumination syndrome. Rumination syndrome is a syndrome in which food regurgitates effortlessly back into the mouth after a meal is completed. It usually occurs in younger women and conceivably could be confused with dysphagia. There is no sensation of food sticking after swallowing, however.
Gastroesophageal reflux disease (GERD). People with more severe GERD may have food regurgitate from the stomach into the esophagus or mouth, particularly when activities increase pressure in the abdomen, for example, with coughing and bending. Regurgitation also may occur at night while persons with GERD are sleeping as in those with swallowing disorders who have food collect in their esophagus.
Heart disease. The spastic motility disorders that cause dysphagia can be associated with spontaneous chest pain, that is, chest pain not associated with swallowing. Despite the presence of dysphagia, spontaneous chest pain always must be assumed to be due to heart disease until heart disease has been excluded as the cause of the chest pain. Therefore, it is important to test carefully for heart disease before considering the esophagus as the cause of chest pain when a patient with dysphagia complains of episodes of spontaneous chest pain.
What tests and procedures diagnose the cause of swallowing problems?
The history from an individual with dysphagia often provides important clues to the underlying cause of the dysphagia.
The nature of the symptom or symptoms provides the most important clues to the cause of dysphagia. Swallowing that is difficult to initiate or that leads to nasal regurgitation, cough, or choking is most likely due to an oral or pharyngeal problem. Swallowing that results in the sensation of food sticking in the chest (esophagus) is most likely due to an esophageal problem.
Dysphagia that progresses rapidly over weeks or a few months suggests a malignant tumor. Dysphagia for solid food alone suggests a physical obstruction to the passage of food, whereas dysphagia for both solid and liquid food is more likely to be caused by a disease of the smooth muscle of the esophagus. Intermittent symptoms also are more likely to be caused by diseases of smooth muscle than obstruction of the esophagus since dysfunction of the muscle often is intermittent.
Preexisting diseases also provide clues. Those with diseases of skeletal muscle (for example, polymyositis), the brain (most commonly stroke), or the nervous system are more likely to have dysphagia on the basis of dysfunction of the oropharyngeal muscles and nerves. People with collagen vascular diseases, for example, scleroderma, are more likely to have problems with the esophageal muscles, especially ineffective peristalsis.
Patients with a history of GERD are more likely to have esophageal strictures as the cause of their dysphagia, though about 20% of patients with strictures have minimal or no symptoms of GERD before the onset of dysphagia. It is believed that reflux that occurs at night is more injurious to the esophagus. There also is a higher risk of esophageal cancer among individuals with long-standing GERD.
Loss of weight can be a sign of either severe dysphagia or a malignant tumor. More often than losing weight, people describe a change in their eating pattern—smaller bites, additional chewing—that prolongs meals so that they are the last one at the table to finish eating. This latter pattern, if present for a prolonged period of time, suggests a non-malignant, relatively stable or slowly progressive cause for the dysphagia. Episodes of chest pain that are not due to heart disease suggest muscular diseases of the esophagus. Birth and residence in Central or South America is associated with Chagas disease.
The physical examination is of limited value in suggesting causes for dysphagia. Abnormalities of the neurological examination suggest neurologic or muscle diseases. By observing an individual swallowing, one can determine if there is difficulty in initiating swallows, a sign of neurological disease. Tumors in the neck suggest the possibility of compression of the pharynx. A trachea that cannot be moved from side to side with the hand suggests a tumor lower down in the chest that has entrapped the trachea and possibly the esophagus. Observing atrophy (reduced size) or fasiculations of the tongue (fine tremors) also suggest diseases of the nervous system or skeletal muscle.
Endoscopy. Endoscopy involves the insertion of a long (one meter), flexible tube with a light and camera on its end through the mouth, pharynx, esophagus, and into the stomach. The lining of the pharynx and esophagus can be evaluated visually, and biopsies (small pieces of tissue) can be obtained for examination under the microscope or for bacterial or viral cultures.
Endoscopy is an excellent means of diagnosing tumors, strictures, and Schatzki's rings as well as infections of the esophagus. It also is very good for diagnosing diverticuli of the middle and lower esophagus but poor for diagnosing diverticuli in the upper esophagus (Zenker's diverticulum).
It is possible to observe abnormalities of esophageal muscular contraction, but esophageal manometry is a test that is much better suited for evaluating function of the esophageal muscles. Resistance passing the endoscope through the lower esophageal sphincter combined with a lack of esophageal contractions is a fairly reliable sign of achalasia or Chagas disease (due to the inability of the lower esophageal sphincter to relax), but it is important when there is resistance to exclude the presence of a stricture or cancer which also can cause resistance. Finally, there is a characteristic appearance of the esophageal lining when infiltrated with eosinophils that strongly suggests the presence of eosinophilic esophagitis.
X-rays. There are two different types of X-rays that can be done to diagnose the cause of dysphagia. The barium swallow or esophagram is the simplest type. For the barium swallow, mouthfuls of barium are swallowed, and X-ray films are taken of the esophagus at several points in time while the bolus of barium traverses the esophagus. The barium swallow is excellent for diagnosing moderate-to-severe external compression, tumors, and strictures of the esophagus. Occasionally, however, Schatzki's rings can be missed.
Another type of X-ray study that can be done to evaluate swallowing is the video esophagram or video swallow, sometimes called a video-fluoroscopic swallowing study. For the video swallow, instead of several static X-ray images of the bolus traversing the esophagus, a video X-ray is taken. The video study can be reviewed frame by frame and is able to show much more than the barium swallow. This usually is not important for diagnosing tumors or strictures, which are well seen on barium swallow, but it is more effective for suggesting problems with the contraction of the muscles of the esophagus and pharynx (though esophageal manometry, discussed later, is still better for studying contraction), milder external compression of the esophagus, and Schatzki's rings. The video study can be extended to include the pharynx where it is the best method for demonstrating osteophytes, cricopharyngeal bars, and Zenker's diverticuli. A modified barium swallow is a version of the test evaluating the oropharyngeal phases of swallowing. A speech pathologist is usually involved with the evaluation to determine subtle sequence and phase abnormalities.
The video swallow also is excellent for diagnosing penetration of barium (the equivalent of food) into the larynx and trachea due to neurological and muscular problems of the pharynx that may be causing coughing or choking after swallowing food.
Esophageal manometry. Esophageal manometry, also known as esophageal motility testing, is a means to evaluate the function of pharyngeal and esophageal muscles. For manometry, a thin, flexible catheter is passed through the nose and pharynx and into the esophagus. The catheter is able to sense pressure at multiple locations along its length in both the pharynx and the esophagus. When the pharyngeal and esophageal muscles contract, they generate a pressure on the catheter which is sensed, measured and recorded from each location. The magnitude of the pressure at each pressure-sensing location and the timing of the increases in pressure at each location in relation to other locations give an accurate picture of how the muscles of the pharynx and esophagus are contracting.
The value of manometry is in diagnosing and differentiating among diseases of the muscle or the nerves controlling the muscles that result in muscle dysfunction of the pharynx and esophagus. Thus, it is useful for diagnosing the swallowing dysfunction caused by diseases of the brain, skeletal muscle of the pharynx, and smooth muscle of the esophagus.
Esophageal impedence. Esophageal impedence testing utilizes catheters similar to those used for esophageal manometry. Impedence testing, however, senses the flow of the bolus through the esophagus. Thus, it is possible to determine how well the bolus is traversing the esophagus and correlate the movement with concomitantly recorded esophageal pressures determined by manometry. (It also can be used to sense reflux of stomach contents into the esophagus among patients with GERD.) Multiple sites along the length of the esophagus can be tested to assess the movement of the bolus and presence of reflux, including how high up it extends.
Esophageal acid testing. Esophageal acid testing is not a test that directly diagnoses diseases of the esophagus. Rather, it is a method for determining whether or not there is reflux of acid from the stomach into the esophagus, a cause of the most common esophageal problem leading to dysphagia, esophageal stricture. For acid testing, a thin catheter is inserted through the nose, down the throat, and into the esophagus. At the tip of the catheter and placed just above the junction of the esophagus with the stomach is an acid-sensing probe. The catheter coming out of the nose passes back over the ear and down to the waist where it is attached to a recorder. Each time acid refluxes (regurgitates) from the stomach and into the esophagus it hits the probe, and the reflux of acid is recorded by the recorder. At the end of a prolonged period, usually 24 hours, the catheter is removed and the information from the recorder is downloaded into a computer for analysis. Most people have a small amount of reflux of acid, but individuals with GERD have more. Thus, acid testing can determine if GERD is likely to be the cause of the esophageal problem such as a stricture, as well as if treatment of GERD is adequate by showing the amount of acid that refluxes during treatment is normal.
An alternative method of esophageal acid testing uses a small capsule containing an acid-sensing probe that is attached to the esophageal lining just above the junction of the esophagus with the stomach. The capsule wirelessly transmits the presence of episodes of acid regurgitation to a receiver carried on the chest. The capsule records for two or three days and later is shed into the esophagus and passes out of the body in the stool.
Other tests The diagnosis of muscular dystrophies and metabolic myopathies usually involves a combination of tests including blood tests that can suggest muscle injury, electromyograms to determine if nerves and muscles are working normally, biopsies of muscles, and genetic testing.
How are swollowing problems treated?
The treatment of dysphagia varies and depends on the cause of the dysphagia. One option for supporting patients either transiently or long-term until the cause of the dysphagia resolves is a feeding tube. The tube for feeding may be passed nasally into the stomach or through the abdominal wall into the stomach or small intestine. Once oral feeding resumes, the tube can be removed.
Physical obstruction of the pharynx or esophagus
Treatment for obstruction of the pharynx or esophagus requires removal of the obstruction.
Tumors usually are removed surgically although occasionally they can be removed endoscopically, totally or partially. Radiation therapy and chemotherapy also may be used particularly for malignant tumors of the pharynx and its surrounding tissues. If malignant tumors of the esophagus cannot be easily removed or the tumor has spread and survival will be limited, swallowing can be improved by placing stents within the esophagus across the area of obstruction. Occasionally, obstructing tumors can be dilated the same way as strictures. (See below.)
Strictures and Schatzki's rings usually are treated with endoscopic dilation, a procedure in which the narrowed area is stretched either by a long, semi-rigid tube passed through the mouth or a balloon that is blown up inside the esophagus.
The most common infiltrating disease causing dysphagia is eosinophilic esophagitis which usually is successfully treated with swallowed corticosteroids. The role of food allergy as a cause of eosinophilic esophagitis is debated; however, there are reports of using elimination diets to identify specific foods that are associated with allergy. Elimination of these foods has been reported to prevent or reverse the infiltration of the esophagus with eosinophils, particularly in children.
Diverticuli of the pharynx and esophagus usually are treated surgically by excising them. Occasionally they can be treated endoscopically. Cricopharyngeal bars are treated surgically by cutting the thickened muscle. Osteophytes also can be removed surgically.
Congenital abnormalities of the esophagus usually are treated surgically soon after birth so that oral feeding can resume.
Diseases of the brain
As previously discussed, strokes are the most common disease of the brain to cause dysphagia. Dysphagia usually is at its worst immediately after the stroke, and often the dysphagia improves with time and even may disappear. If it does not disappear, swallowing is evaluated, usually with a video swallowing study. The exact abnormality of function can be defined and different maneuvers can be performed to see if they can counter the effects of the dysfunction. For example, in some patients it is possible to prevent aspiration of food by turning the head to the side when swallowing or by drinking thickened liquids (since thin liquids is the food most likely to be aspirated).
Tumors of the brain, in some cases, can be removed surgically; however, it is unlikely that surgery will reverse the dysphagia. Parkinson's disease and multiple sclerosis can be treated with drugs and may be useful in patients with dysphagia.
Diseases of smooth muscle of the esophagus
Achalasia is treated like a stricture of the esophagus with dilation, usually with a balloon. A second option is surgical treatment in which the muscle of the lower esophageal sphincter is cut (a myotomy) in order to reduce the pressure and obstruction caused by the non-relaxing sphincter. Drugs that relax the sphincter usually have little or a transient effect and are useful only when achalasia is mild.
An option for individuals who are at high risk for surgery or balloon dilation is injection of botulinin toxin into the sphincter. The toxin paralyzes the muscle of the sphincter and causes the pressure within the sphincter to decrease. The effects of botulinin toxin are transient, however, and repeated injections usually are necessary. It is best to treat achalasia early before the obstruction causes the esophagus to enlarge (dilate) which can lead to additional problems such as food collecting above the sphincter with regurgitation and aspiration.
In other spastic motility disorders, several drugs may be tried, including anti-cholinergic medications, peppermint, nitroglycerin, and calcium channel blockers, but the effectiveness of these drugs is not clear and studies with them are nonexistent or limited.
For patients with severe and uncontrollable symptoms of pain and/or dysphagia, a surgical procedure called a long myotomy occasionally is performed. A long myotomy is similar to the surgical treatment for achalasia but the cut in the muscle is extended up along the body of the esophagus for a variable distance in an attempt to reduce pressures and obstruction to the bolus.
There is no treatment for ineffective peristalsis, and individuals must change their eating habits. Fortunately, ineffective peristalsis infrequently causes severe dysphagia by itself. When moderate or severe dysphagia is associated with ineffective peristalsis it is important to be certain that there is no additional obstruction of the esophagus, for example, by a stricture due to GERD, that is adding to the effects of reduced muscle function and making dysphagia worse than the ineffective peristalsis alone. Most causes of obstruction can be treated.
Diseases of the skeletal muscle of the pharynx
There are effective drug therapies for polymyositis and myasthenia gravis that should also improve associated dysphagia. Treatment of the muscular dystrophies is primarily directed at preventing deformities of the joints that commonly occur and lead to immobility, but there are no therapies that affect the dysphagia. Corticosteroids and drugs that suppress immunity sometimes are used to treat some of the muscular dystrophies, but their effectiveness has not been demonstrated.
There is no treatment for the metabolic myopathies other than changes in lifestyle and diet.
There is no treatment for Alzheimer's disease.
What is the prognosis for dysphagia?
With the exception of dysphagia caused by stroke for which there can be marked improvement, dysphagia from other causes is stable or progressive, and the prognosis depends on the underlying cause, its tendency to progress, the availability of therapy, and the response to therapy.
- In general, the prognosis for non-malignant obstruction of the esophagus is good with treatment. Even dysphagia caused by malignant obstruction can be palliated with endoscopic resection of part of the tumor and/or stenting.
- Neurologic and muscular diseases causing dysphagia are a mixed bag.
- Treatment of achalasia is quite effective, treatment for spastic motility disorders much less so.
- As mentioned previously, ineffective peristalsis by itself usually does not cause important or progressive dysphagia.
- Progressive neurologic and skeletal muscle diseases are the most difficult to treat and carry the worst prognosis.
What does the future offer for dysphagia?
Recent developments in the diagnostic arena are beginning to bring new insights into esophageal function, specifically, high resolution and 3D manometry, and endoscopic ultrasound.
High resolution and 3D manometry
High resolution and 3D manometry are extensions of standard manometry that utilize similar catheters. The difference is that the pressure-sensing locations on the catheters are very close together and ring the catheter. Recording of pressures from so many locations gives an extremely detailed picture of how esophageal muscle is contracting. The primary value of these diagnostic procedures is that they "integrate" the activities of the esophagus so that the overall pattern of swallowing can be recognized, which is particularly important in complex motility disorders. In addition, their added detail allows the recognition of subtle abnormalities and hopefully will be able to help define the clinical importance of subtle abnormalities of muscle contraction associated with lesser degrees of dysphagia.
Endoscopic ultrasonography has been available for many years but has recently been applied to the evaluation of esophageal muscle diseases. Ultrasound uses sound waves to penetrate tissues. The sound waves are reflected by the tissues and structures they encounter, and, when analyzed, the reflections give information about the tissues and structures from which they are reflected. In the esophagus, endoscopic ultrasonography has been used to determine the extent of penetration of tumors into the esophageal wall and the presence of metastases to adjacent lymph nodes. More recently, endoscopic ultrasonography has been used to obtain a detailed look at the muscles of the esophagus. What has been found is that in some disorders, particularly the spastic motility disorders, the muscle of the esophagus is thickened. Moreover, thickening of the muscle sometimes can be recognized only by ultrasonography even when spastic abnormalities are not seen with manometry. The exact role of endoscopic ultrasonography has not yet been determined but is an exciting area for future research.
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REFERENCE: Feldman, M., Scharschmidt, B. F., Sleisenger, M. H., Klein, S. Sleisenger & Fordtran's Gastrointestinal and Liver Disease, W. B. Saunders Company, 1998.