Diseases and Disorders
Esophageal Motility Disorders
Esophageal motility disorders encompass a broad class of diseases that are manifest by abnormal contractions of the esophageal body as well as abnormal function of both the upper and lower esophageal sphincters. Symptoms are quite variable, and can manifest as the sensation of food sticking, chest pain, or regurgitation. These disorders are notoriously difficult to assess on the basis of symptoms, and precise, reliable testing is critical to make the correct diagnosis.
- Dedicated esophageal diagnostic lab run by USC thoracic surgeons with integrated esophageal function testing and endoscopy
- State of the art diagnostic technology that allows for individualization of the diagnostic evaluation to the patient’s specific circumstances
- Tailoring of the antireflux operation to the patient’s disease and physiology
- Extensive experience in re-operative procedures and remedial operations
- High-volume referral center for esophageal motility disorders with knowledgeable thoracic surgeons, nurses, and staff
Mechanism of Disease
The esophagus is a muscular tube that connects the pharynx in the throat to the stomach. There are two sphincters at each end, an upper esophageal sphincter and a lower esophageal sphincter. With normal swallowing there is an incredible coordination of neurologic and muscular events for the food or liquid to efficiently pass from the mouth and into the stomach. Any dysfunction in this process can manifest as difficulty swallowing solids and liquids, regurgitation of undigested food, chest pain, and even heartburn.
Disorders related to the upper esophageal sphincter or cricopharyngeal muscle are usually related to extremely high contraction of this muscle. This leads to difficulty swallowing, and over time can lead to an outpouching above this sphincter known as a Zenker’s diverticulum.
Disorders related to the lower esophageal sphincter can be due to either extremely high muscle contraction tone or extremely low contraction tone. If the sphincter tone is too high and does not open with swallowing, patients often experience difficulty passing food. This may be associated with complete loss of peristalsis in the body of the esophagus in a condition known as achalasia. It may also be an isolated disorder that can be associated with an outpouching of the esophagus above it, known as an epiphrenic diverticulum. In some cases a hypertensive lower esophageal sphincter can paradoxically occur in the setting of reflux disease. If the lower esophageal sphincter tone is too low, uncontrolled reflux of gastric contents may occur. Other than in the setting of GERD, this finding may occur with some connective tissue disorders, such as scleroderma.
Motor disorders of the esophagus can result in complete loss of peristalsis, as in achalasia, or decreased strength of contractions such as in ineffective esophageal motility. These disorders usually manifest as difficulty swallowing both solids and liquids. In other disorders, such as in the setting of extremely high contractions of the esophageal body or nutcracker esophagus, chest pain is a predominant symptom.
The USC Center for Esophageal Disorders is a renown referral center for patients from around the country for diagnostic studies and a wide variety of treatment options. Unique to USC, the thoracic surgeons supervise the diagnostic testing themselves, interpret the results directly, and perform their own endoscopies. This organ-centered approach allows the surgeon to comprehensively assess the patient, and therefore recommend the best treatment tailored to the individual patient. The high-tech diagnostic studies that are performed are always personally reviewed by the thoracic surgeons, as experience has shown that subtle findings are sometimes missed by the automatic reports generated by the computer.
Esophageal manometry is a diagnostic test that uses tiny transducers or receivers that are integrated into a thin catheter or tube that is inserted into the esophagus to measure pressure. This device is used to measure the LES length and resting pressure, its ability to relax with swallowing, the contractile strength and coordination of the esophageal body, and the upper esophageal sphincter characteristics. There are several manometry catheters that are available at the USC Center for Esophageal Disease, and the most appropriate one will be selected by the patient’s thoracic surgeon appropriate for the circumstances. Standard manometry catheters may be used, or high-resolution catheters (ManoScan®). Additionally, impedance technology may be necessary to further monitor how effective the esophagus can clear swallowed liquids.
A video esophagram is a radiologic study that is performed by dedicated radiologists with a focus in esophageal disorders. During this examination, the patient is asked to swallow barium liquid 5 times and soft food 2 times while a special x-ray machine videotapes the clearance of the swallowed material. This gives additional information regarding the function of the esophagus. It also provides information regarding any anatomic abnormalities that may be present, such as strictures, a hiatal hernia, or a diverticulum or outpouching of the esophagus.
Upper endoscopy is a critical component of assessing a patient for GERD, and USC thoracic surgeons are keenly interested in performing this procedure to visualize the esophagus and stomach for evidence of injury related to GERD. In addition, anatomic details critical for pre-operative planning may be observed during this procedure, such as strictures or a hiatal hernia. Endoscopy also allows the thoracic surgeon to assess patients for potential reasons for anemia related to a paraesophageal hernia. Finally, GERD can cause a pre-cancerous condition known as Barrett’s esophagus and even cancer itself, so the endoscopic examination allows the thoracic surgeon to ensure that these potentially life-threatening complications of GERD have not occurred.
Depending on the specific esophageal motility disorder that is diagnosed, either medical therapy or surgical therapy may be recommended. The most common esophageal motility disorder is achalasia, a condition in which the lower esophageal sphincter does not open or relax appropriately when a patient swallows. It is also associated with loss of peristalsis in the esophageal body. There are several options for achalasia, including medical therapy, endoscopic therapy, and surgery.
Medical options for achalasia include medications that help relax smooth muscle in the body, such as calcium channel blockers or nitroglycerin, drugs that are more commonly used for cardiovascular disease. Outcomes with use of these medications have been disappointing, and are rarely used as the sole means of treatment.
Endoscopic techniques are available for achalasia treatment. The least invasive but also least durable option is endoscopic injection of botox into the lower esophageal sphincter. This relaxes the muscle and gives some improvement in the sensation of dysphagia or difficulty swallowing. The main drawback is that the medication wears off and does not last more than a few months. In addition, repeated therapy can result in scarring that can make future surgery more complex.
Another endoscopic option is dilatation, which is done with a specially designed balloon that is inflated to rupture the lower esophageal sphincter.[FIGURE] This has been a good option for patients who are too high risk of definitive surgery. One issue, however, is that the effect is not as durable as surgery, and repeat procedures are usually necessary. For this reason balloon dilatation is usually not recommended for younger patients. Another concern is the risk of esophageal perforation.
The surgical option for achalasia is an operation known as a Heller myotomy, which is usually done laparoscopically or through a few tiny incisions in the abdominal wall. This operation involves precise cutting of the thick, noncompliant lower esophageal sphincter to allow it to permanently open up, and is considered to the gold standard for treatment of this condition. It is accompanied by a partial antireflux procedure known as a Dor partial fundoplication to prevent uncontrolled reflux.[FIGURE]
The two main treatment options remain balloon dilatation or laparoscopic Heller myotomy. Medical therapy and botox injection are considered temporary treatments that are not definitive. The main difference between balloon dilatation and surgical myotomy is durability. Dilatation can effect good short term outcomes, but usually require re-intervention to maintain its effect, whereas surgery is more definitive. Long term follow up for several decades of patients who have undergone this operation has revealed excellent durability.
Novel endoscopic therapy is emerging and being evaluated by USC thoracic surgeons for the treatment of achalasia. One such technique is called POEM or peroral endoscopic myotomy. This involves the cutting of the lower esophageal sphincter from the inside using special endoscopic instruments to reproduce what is done surgically. POEM is being investigated for feasibility and short term outcomes at this time.