An endoscopy uses a flexible tube with a camera called an endoscope to examine structures inside a patient’s body. The lining of the digestive tract is examined during a procedure known as a gastrointestinal (GI) endoscopy. During this procedure, the endoscope is either passed through the mouth to view the esophagus, stomach and most of the small intestine, or through the anus to view the anus, rectum and lower large intestine. The images provided by an endoscopy may not be available using other techniques, and endoscopic images are often superior to those of a standard x-ray.

An endoscopy will be performed by a gastroenterologist, a physician who has expertise in both GI disorders and in using an endoscope. Signs and symptoms that may cause a physician to order a GI endoscopy include bleeding, abdominal pain, difficulty swallowing and a change in bowel habits.

Endoscopy can be used to diagnose or treat many disorders of the digestive system. Some examples of such disorders include:

• Inflammatory bowel disease
• Peptic ulcers
  

  

• Diverticulosis
• Appendicitis
• Gallbladder stones
• Colon polyps
• Colon cancer
  

  

The endoscope itself is a long flexible tube with several channels that can project light on the area being examined. A camera attached to the tip of the tube allows images to be captured. Air also can be pumped through the tube to expand tissue folds, making it easier to see the stomach. Surgical instruments can be passed through the endoscope to perform surgery, and a small clipper attached to the endoscope can be used to collect a sample for biopsy.

Endoscopes range between 1 foot and 5 feet (0.30 to 1.52 meters) in length, and between 1/4 inches and 1/2 inch (0.64 to 1.27 centimeters) in diameter. Different-sized endoscopes are used to examine various parts of the digestive tract. Endoscopes can reveal the presence of irritation and inflammation, as well as features such as tissue growth, hiatal hernia or ulcers.

In some cases, a physician may discover an apparent abnormality during examination that requires further analysis by biopsy. A small clipper attached to the endoscope can be used to obtain a tissue sample that is then analyzed in a laboratory. This analysis can help determine the cause of the abnormality (e.g., inflammation, infection, cancer). Patients do not typically experience pain when the sample is removed because few nerves exist in the lining and inner walls of the digestive tract.