Newer types of endoscopy
In recent years, researchers have developed other ways of using instruments to look inside the body. These methods are often referred to as newer forms of endoscopy, even though they don’t put tubes into the body.
Doctors can see a lot of the digestive tract using upper endoscopy or colonoscopy. But it’s harder for the 20 feet or so of small intestine to be seen this way, although enteroscopy (EN-ter-AH-skuh-pee) can be used. Cancers in this area are rare, but tumors and other problems such as ulcers can develop here.
One way to look at this area is to use capsule endoscopy. To do this, a person swallows a capsule that contains a light source and a tiny camera. (It’s about the size of a large vitamin pill.) Like any other pill, the capsule goes through the stomach and into the small intestine. It travels through the small intestine, which usually takes about 8 hours, and takes thousands of pictures. These pictures are sent to a device worn around the person’s waist, while he or she goes on with normal daily activities. The pictures can then be downloaded onto a computer, where the doctor can look at them as a video. The capsule passes out of the body during a normal bowel movement and is flushed away.
This technique may help find the source of bleeding, pain, or other symptoms that may be coming from the small intestine. But it’s not useful for looking closely at the colon or other parts of the body. It costs a lot, so you will need to find out if your insurance company will cover it before having it.
Virtual endoscopy is really an imaging test, not an endoscopy procedure. It uses a special CT scan to look at the inside surfaces of organs such as the lungs (virtual bronchoscopy) or colon (virtual colonoscopy or CT colonography).
Patients have this procedure just as they would any other CT scan — they lie still on a table while a large ring (the CT scanner) passes over the part of the body being imaged.
Unlike the usual CT scans, which make pictures in 2 dimensions, virtual endoscopy uses a computer to combine many images to create a 3-dimensional (3-D) picture. Doctors can even use the images to create a black and white “fly-through” view on the screen, which looks a lot like it would if they were doing an actual endoscopy.
Virtual endoscopy has some advantages over standard endoscopy — nothing is put into the body and no drugs are needed for the test. The doctor can change the angle or magnify the image, which can help with diagnosis.
But there are some disadvantages, too. Virtual endoscopy does show good detail, but it’s not quite as good at showing fine surface detail as standard endoscopy. (For example, it can’t show color differences.) It also exposes the patient to about the same amount of radiation as a standard CT. And because nothing is put into the body, the doctor can’t take biopsy samples or remove growths. This means that if something abnormal is found, the patient may still need a standard endoscopy. To get good pictures on a virtual colonoscopy, the patient must still take medicines (laxatives and/or enemas) to clean out the colon.
Virtual endoscopy is a fairly new procedure, and doctors aren’t yet sure how best to use it. It will likely be used more in the future as the technology improves.