The esophagus is an organ that consists of a muscular tube through which food passes to the stomach. It is usually about 25–30 cm long and is divided into cervical, thoracic and abdominal parts. The entry to the esophagus opens only when swallowing or vomiting.

Barrett’s Esophagus: Barrett's esophagus is a disorder in which the lining of the esophagus is damaged by stomach acid and changed to a lining similar to that of the stomach. When you eat, food passes from your throat to your stomach through the esophagus. Once food is in the stomach, a ring of muscles keeps it from leaking backward into the esophagus. If these muscles do not close tightly, stomach acid can leak back into the esophagus. This is called reflux or gastroesophageal reflux. Patients with Barrett's esophagus may develop more changes in the esophagus called dysplasia. When dysplasia is present, the risk of getting cancer of the esophagus increases. While looking at the esophagus with an endoscope, a gastroenterologist may perform biopsies in different parts of the esophagus. These biopsies help diagnose Barrett's esophagus, and look for changes that could lead to cancer.

Dysphagia: Dysphagia is difficulty swallowing. Sometimes this may be felt as something stuck in the throat that won't go down. This may have a number of causes that require testing or procedures such as EGD for diagnosis.

Gastroesophageal Reflux Disease (GERD): Gastroesophageal Reflux Disease (GERD) is a term used to describe several digestive conditions with different degrees of severity. These conditions are caused by the regurgitation or back-up of stomach acid into the esophagus (the food tube which connects the mouth to the stomach). Heartburn is the most common symptom of GERD. Although many people have occasional heartburn, when it becomes almost constant, the condition is a more serious problem, called reflux esophagitis. If the lower esophagus is exposed to too much acid over a prolonged period, the area can become badly damaged with ulcers and strictures.

Hiatal Hernia: Hiatal hernia is a condition in which part of the stomach sticks upward into the chest, through an opening in the diaphragm. The diaphragm is used in breathing; it is the sheet of muscle that separates the chest from the abdomen. Hiatal hernias may be due to a weakening of the supporting tissue. Increasing age, obesity, and smoking are known risk factors in adults. Hiatal hernias are very common, especially in people over 50 years old. This condition may cause reflux (backflow) of gastric acid from the stomach into the esophagus.

Esophageal and Stomach Varices: Scarring (cirrhosis) of the liver is the most common cause of esophageal varices. This scarring prevents blood from flowing through the liver. As a result, more blood flows through the veins of the esophagus. This extra blood flow causes the veins in the esophagus to balloon outward. If these veins break open (rupture), they can cause severe bleeding. Any cause of chronic liver disease can cause varices. The swollen veins (varices) can also occur in the upper part of the stomach.