The oesophagus is the muscular tube that leads from the mouth to the stomach. Swallowed food is massaged down the oesophagus and passed through a weak ring of muscle (sphincter) into the stomach. Reflux occurs when the acidic contents of the stomach squeeze or 'slosh' back through the sphincter and enter the lower oesophagus, causing symptoms such as heartburn (a burning sensation in the lower chest) or regurgitation.
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Below are a few common conditions of the oesophagus, click on the desired conditions to find out more about them.
:: Barret's oesophagus
People who experience persistent symptoms of reflux (for more than five years) are at risk of developing Barrett's oesophagus. This is a condition where the cells lining the lower oesophagus change in appearance to resemble those of the stomach and intestine. Importantly, Barrett's oesophagus is a risk factor for cancer of the lower oesophagus. The chronic reflux of gastric juices causes these cellular changes, which may eventually turn cancerous. Symptoms of Barrett's oesophagus are usually no different from regular heartburn, and on occasions may be fairly trivial. This means that many people don't seek medical treatment until their condition is quite advanced. In fact, most people with cancer of the lower oesophagus have not been previously diagnosed with reflux. Barrett's oesophagus is more common in men than women.
:: Symptoms
Barrett's oesophagus is suspected when there are symptoms of persistent gastric reflux or symptoms of complicated reflux. These symptoms include:
- Persistent heartburn
- Difficulty swallowing
- Painful swallowing
- Vomiting
- Weight loss
- A sensation of fullness during eating.
:: Cellular changes
A normal oesophagus is lined with pinkish-white, flat, smooth cells (squamous cells) that allow the easy passage of swallowed food. The lining of the stomach comprises tall and red cells that secrete special acid-resistant mucus. Refluxed food, gastric juices and (possibly) bile inflame and irritate the cells lining the oesophagus because they are not acid-resistant. The resulting pain and discomfort is known as heartburn. Without treatment, constant exposure to these juices can eventually cause cellular changes in the lower oesophagus. The red mucus-secreting cells normally found in the stomach replace the flat and smooth cells. The presence of red cells in the oesophagus indicates Barrett's oesophagus.
:: Cancer risk
In a percentage of cases, these cellular changes turn cancerous. Studies in the United States have discovered that the rate of cancer caused by Barrett's oesophagus is on the increase. If detected early, cancer of the oesophagus can be treated successfully by surgery. However, many people with cancer caused by Barrett's oesophagus don't seek medical advice until the tumour is too advanced for curative treatment.
:: Diagnosis methods
Diagnosing Barrett's oesophagus involves a number of tests, including:
Endoscopy - a thin tube is swallowed so that the doctor can see inside the oesophagus.
Endoscopic biopsy - a small tag of tissue is removed during an endoscopy and examined for the presence of cellular changes. Barrett's oesophagus cannot be diagnosed without this biopsy.
Twenty-four hour ambulatory pH monitoring - a thin wire is threaded through the nose into the oesophagus and connected to a small recorder. This device is worn on the body, usually for 24 hours. This records the level of acid bathing the lower gullet and is an effective way of proving that therapy is adequate.
:: Hiatus Hernia
A hiatus hernia (also known as a hiatal hernia) occurs when a portion of the stomach slides or protrudes through a gap in the diaphragm (a thin muscle that separates the stomach from the chest) up into the chest cavity. A hernia is a bulge or protrusion of part of the body into another part of the body that would normally contain it.
There are 2 main types of hiatus hernia.
- Sliding hiatus hernia: this is the most common type of hiatus hernia. It occurs when the junction between the oesophagus and the stomach and the upper part of the stomach protrude up through the oesophageal opening in the diaphragm into the chest cavity. The herniated portion of the stomach can slide back and forth, into and out of the chest.
- Rolling hiatus hernia: this is sometimes called a para-oesophageal hiatus hernia by doctors. In this case, part of the stomach bulges into the chest out of the weakest part of the diaphragm, which is the oesophageal opening. The junction of the oesophagus and stomach stays down within the abdomen, and the top part of the stomach (the fundus) bulges up into the chest cavity. This type of hernia normally remains in one place, sitting next to the oesophagus, and does not move in or out when you swallow.
:: Achalasia
Achalasia, is a disorder of the oesophagus where the lower oesophageal sphincter doesn't relax properly with swallowing.
Under normal circumstances, when you swallow, food is passed down the oesophagus by waves of muscle contractions and into the stomach.
:: Lower oesophageal sphincter
A 'valve', which doctors call a sphincter, controls the entry of food from the lower end of the oesophagus into the stomach. This particular sphincter is known as the lower oesophageal sphincter. It is a band of muscle that opens to allow the food to pass from the oesophagus down into your stomach and then closes again to prevent the acidic stomach contents from coming back up.
In achalasia the lower oesophageal sphincter doesn't relax properly with swallowing, which means that food is not pushed down into the stomach. Instead, it becomes lodged in the oesophagus. This happens because achalasia affects the nerves that control the sphincter muscles.
Another feature of achalasia is that the normal rhythmic contractions of the oesophagus, which propel food down it towards the stomach (doctors call this peristalsis), are lacking. Doctors think that this may be due to a malfunction of the nerves that encase the oesophagus.
Achalasia can happen at any age, but begins most often between 20 and 40 years of age. It can start almost unnoticed, gradually advancing over a long period.
:: Oesophageal cancer
Oesophageal cancer (also called cancer of the oesophagus) is a malignant tumour that grows in the lining of the oesophagus. The oesophagus (the gullet) is the tube that carries food from the mouth down into the stomach using a series of muscular movements.
:: Types of oesophageal cancer
Two types of cancer, squamous cell carcinoma and adenocarcinoma, make up 90 per cent of all oesophageal cancers. Oesophageal cancer can occur in any section of the oesophagus. Most cancers in the top part of the oesophagus are squamous cell cancers. They are called this because the cells lining the top part of the oesophagus are squamous cells. Squamous means scaly.
Most cancers at the end of the oesophagus that joins the stomach are adenocarcinomas. Adenocarcinomas are often found in people who have a condition called Barrett's oesophagus.