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Abstract The oesophagus is a muscular tube serves as a conduit for the passage of food from the pharynx to the stomach. Separating its lower end from the stomach is a zone of increased pressure that acts as a barrier to reflux of stomach contents but allows materials to pass in both directions. The act of swallowing is accomplished by the coordinated movement of striated muscles and the striated and smooth musculature of the tubular oesophagus, all under central control. Each individual has an unique swallowing pattern and the increasingly widespread use of various oesophageal function tests has clarified the nature of a variety of oesophageal motility disorders. As a result, most benign conditions of the oesophagus can now be classified according to their specific abnormal motility pattern. The oesophageal motility disorders classified according to the system affected to; diseases affect the upper oesophageal sphincter and those involving the body of the oesophagus and lower oesophageal sphincter. ..Upper oesophageal dysphagia may follow certain lessions of the central nervous system; muscular diseases due to impairment of pharyngeal contractions and after extensive operations on the oropharynx, presumbly because of impaired function of the cricopharyngeus muscle. ”Spasm” or hypertension of the upper oesophageal sphincter is another possible cause of oropharyngeal dysphagia. The most common entity responsible for upper oesophageal dysphagia is pharyngo-oesophageal diverticulum or Zenker’s diverticulum. Cricopharyngeal myotomy has played an increasing role in the management of abnormalities of function of the upper oesophageal sphincter. More is known about the abnormalities affecting the body of the oesophagus and its lower sphincter than about those of the upper sphincter, hence, this rather arbitary division in the classification. A further division into abnormalities of function characterized by hypo-and-hypermotility is useful for it has clinical and therapeutic implication. Even so, many major gaps in our knowledge remain regarding the function of the body and the lower sphincter, as indicated by the number of conditions listed under ”miscellaneous” which ·reflects the complixity of the response of this part of the oesophagus to a wide variety of conditions. Oesophageal achalasia is a disease of unknown origin characterized by the absence of peristalsis in the body of the oesophagus, failure of or incom( plete relaxation of the lower oesophageal sphincter in response to swallowing and a. higher than normal resting lower oesophageal sphincter pressure. Surgical treatment provides a higher success rate and long lasting relief of dysphagia than forceful dilation. One of the most common abnormalities of oesophageal function is gastro-oesophageal reflux secondary to hypotension of the lower oesophageal sphincter. Hypotensive lower oesophageal sphincter exists in a variety of conditions, probably the most Common of which is sliding oesophageal hiatus hernia. The diagnosis of gastro-oesophageal reflux secondary to hypotensive lower oesophageal sphincter is based on clinical, roentogenographic, endoscopic and manometric criteria. Objective evidence of gastrooesophageal reflux must be sought in such patients because the symptoms may not always definitive to confirm the diagnosis. Probably the most sensitive test for reflux is the pH reflux test, with manometry and cinefluorography being less reliable indexes. Treatment is primarily medical and is designed to minimize the occasions of reflux and its effects by reducing gastric acids. In a small percentage of patients, surgical treatment in the form of aifantireflux poceduros required. Hypermotility disturbances of the oesophagus (137) are less common than hypomotility disturbances. Most frequently encountered is diffuse spasm of the oesophagus, a functional abnormality that may or may not be associated with elevated lower oesophageal sphincter pressures. Manometric studies usually identify the abnormality as restricted to the lower two third of the oesophagus. The deglutitory peristaltic front is usually lost and is replaced by simultaneous, repetitive, prolonged contractions of great amplitude that may occur spontaneously. Medical treatment. is usually unavailing although some success has been reported with nitroglycerine. Dilatation has been successful in some patients. Surgical treatment in the form of oesophagomyotomy has been useful in relieving the symptoms of pain and dysphagia. Vigorous achalasia and Chagas disease does not follbw any classifications. Manometric character in vigorous achalasia, are simultaneous oesophageal contractions frequently of high amplitude occur in response to swallowing symptomatic disturbance of oesophageal motility found soon after acute phase of Chagas disease. |