A colonoscopy (koe-lun-OS-kuh-pee) is an exam used to detect changes or abnormalities in the large intestine (colon) and rectum.
During a colonoscopy, a long, flexible tube (colonoscope) is inserted into the rectum. A tiny video camera at the tip of the tube allows the doctor to view the inside of the entire colon.
If necessary, polyps or other types of abnormal tissue can be removed through the scope during a colonoscopy. Tissue samples (biopsies) can be taken during a colonoscopy as well.
Your doctor may recommend a colonoscopy to:
During a colonoscopy, the doctor uses a colonoscope, a long, flexible, tubular instrument about 1/2-inch in diameter that transmits an image of the lining of the colon so the doctor can examine it for any abnormalities. The colonoscope is inserted through the rectum and advanced to the other end of the large intestine.
A colonoscopy can help a doctor find the cause of symptoms, such as
A colonoscopy can be done to look for a number of things.
A colonoscopy is often done to check what's causing your bowel symptoms, such as:
Most of the time it will not find anything to worry about.
But sometimes it might find something that needs a closer look or further testing.
Lots of people have growths in their bowels, and most of the time they're harmless. But they can sometimes become cancer, so if they're found they need to be checked.
They can be removed during the colonoscopy and tested.
Your results will tell you if you need any further tests or treatment.
Before a colonoscopy, let your doctor know about any special medical conditions you have, including the following:
Prior to colonoscopy, intravenous fluids are started, and the patient is placed on a monitor for continuous monitoring of heart rhythm and blood pressure as well as oxygen in the blood. Medications (sedatives) usually are given through an intravenous line so the patient becomes sleepy and relaxed, and to reduce pain. If needed, the patient may receive additional doses of medication during the procedure. Colonoscopy often produces a feeling of pressure, cramping, and bloating in the abdomen; however, with the aid of medications, it is generally well-tolerated and infrequently causes severe pain.
After your colonoscopy:
Complications of colonoscopy are rare and usually minor when performed by physicians who have been specially trained and are experienced in colonoscopy.
Bleeding may occur at the site of biopsy or removal of polyps, but the bleeding usually is minor and self-limited or can be controlled through the colonoscope. It is quite unusual to require transfusions or surgery for post-colonoscopic bleeding. An even less common complication is a perforation or a tear through the colonic wall, but even these perforations may not require surgery.
Other potential complications are reactions to the sedatives used, localized irritation to the vein where medications were injected (leaving a tender lump lasting a day or two), or complications from existing heart or lung disease. The incidence of all of these complications together is less than 1%.
While these complications are rare, it is important for patients to recognize early signs of a complication so that they may return to their physicians or an emergency room. The colonoscopist who performed the colonoscopy should be contacted if a patient notices severe abdominal pain, rectal bleeding of more than half a cup, or fever and chills.