One of the most important medical advances in the past century was the development of the endoscope. This tool, which in its simplest form is a slim tube with a light source and a camera or video camera at its end, enables a doctor to view certain organs or areas inside of a person's body. Prior to the development of endoscopes, people often had to undergo exploratory surgery to determine the cause of their problem.

The exact type of endoscope depends on what part of the body needs to be viewed. Once inserted into the body, the endoscope allows the doctor to view the area in question in order to diagnose diseases or detect problems, such as ulcers, polyps, or tumors.

In addition to their valuable diagnosis and detection qualities, endoscopes are also therapeutic tools. They allow doctors to remove colon polyps or perform surgeries through small incisions in the skin. Doctors can do these, and more, techniques by inserting another tube with an instrument at its end through a channel in the endoscope. Some of the accessories a doctor may use include:

• Flexible forceps, to obtain a tissue sample



• Biopsy forceps, to obtain a tissue sample or remove a suspicious area, such as a polyp in the colon



• Cytology brush, to obtain cell samples



• Suture removal forceps, to remove internal stitches



• Wire baskets, to collect foreign bodies

Additionally, doctors may use the endoscope to deliver laser therapy, photodynamic therapy, drugs, or even to perform surgery.

Earlier technology required endoscopes to be fairly rigid. Advances in fiber optics have allowed endoscopes to become thinner and more flexible since the light can travel through tiny, flexible glass fibers instead of a rigid, hollow tube. These advances have allowed doctors to view parts of the body that were unreachable with earlier tools and also have made the procedures more comfortable for the patient. Originally, this technique was only used on the upper gastrointestinal tract (esophagus, stomach) and lower gastrointestinal tract (colon, sigmoid colon). Currently, diseases of the ear, nose, and throat, as well as the heart, urinary tract, joints, and abdomen can be diagnosed and sometimes treated by these tools.

The length and flexibility of the endoscope depends on its intended use. For example, an endoscope for arthroscopy (viewing of joints) may be quite rigid, whereas one for viewing the colon is flexible.

Following are some of the most common types of endoscopic techniques.

Endoscopic procedures can be done with local, general, or no anesthesia, depending upon the exact procedure. Doctors performing endoscopic techniques undergo extensive training to learn the procedures and participate in continuing education to stay abreast of new developments in technology and its applications.

Side effects and complications from endoscopic procedures are not common, but they can occur. The main complication is the possibility of puncturing the area being examined, such as the colon during a colonoscopy. Bleeding may also occur. Infections can occur from these procedures by the introduction of bacteria into the body. However, these complications are uncommon and it is generally agreed that the benefits of endoscopic procedures far outweigh their risks.

Endoscopy can often be done on an outpatient basis, meaning there is no need for an overnight hospital stay.

In addition to the endoscopic techniques mentioned in the table above, virtual colonoscopy is a relatively new diagnostic tool that is not a true endoscopic technique. Virtual colonoscopy relies on computed tomography (CT) scans of thin segments of the colon to be assembled by a computer to create a view of the inside of the colon. There is no endoscope inserted into the colon, hence the name "virtual". The procedure offers much promise for being highly effective at finding colon polyps or cancers while sparing the people the actual procedure of colonoscopy. However, the preparation for the two techniques is the same and requires thorough bowel cleaning in order to obtain good results.

Additional resources

Upper Endoscopy–What to Expect

Colonoscopy–What to Expect

Sigmoidoscopy–What to Expect