Look Inside the Colon with Sigmoidoscopy
What is a colonoscopy?
A colonoscopy is a procedure that allows your doctor to examine the lining of your colon and rectum using a thin, flexible instrument called a colonoscope. The colonoscope has a camera that transmits pictures of the inside of your colon to a video screen. A colonoscopy is an important test that can help detect colorectal cancer in its earliest, most curable stage and other serious conditions.
The colon and the rectum make up the large intestine, sometimes called the large bowel. The large intestine is a long, hollow organ in your abdomen that plays an important role in digestion by removing water from digested material and forming feces. In addition to looking for signs of colorectal cancer, a colonoscopy can help your doctor find the reason for unexplained intestinal symptoms you may be having, such as changes in your bowel movements, abdominal pain, or rectal bleeding.
Colonoscopy is only one method used to screen for colon cancer. You should discuss different screening options with your doctor or healthcare provider to best understand which option is right for you.
Types of colonoscopy
The types of colonoscopy procedures include:
- Colonoscopy is an endoscopy procedure which involves inserting a colonoscope into the large intestine through the anus. The colonoscope contains a camera that transmits pictures of the inside of your colon to a computer screen.
- Virtual colonoscopy is a type of computerized tomography (CT) scan that uses X-rays to produce images of the inside of the large intestine. Despite its name, virtual colonoscopy is not an actual endoscopy procedure because it does not involve inserting a colonoscope into the large intestine.
Other procedures that may be performed
In addition to a colonoscopy, your doctor may also recommend one or more additional procedures to diagnose or treat certain conditions. The following procedures may be performed during the colonoscopy procedure:
- Control of bleeding in the large intestine by injecting medications or closing off bleeding vessels with heat or applying clips
- Removal of colon polyps, which are abnormal growths in the large intestine that can become cancerous
- Tissue biopsy, which involves removing samples of abnormal looking intestinal tissues to be examined for disease or malignancy
Why is a colonoscopy performed?
Your doctor may recommend a colonoscopy to diagnose and possibly treat a variety of diseases and conditions of the colon and rectum including:
- Abdominal pain if the underlying cause has not been found through less invasive testing. Abdominal pain can be caused by many different conditions, such as inflammatory bowel disease, diverticulitis, and intestinal ulcer.
- Anemia (low red blood cell count) if the underlying cause has not been found through less invasive testing. A colonoscopy can be used to identify potential bleeding sites.
- Bleeding symptoms, such as rectal bleeding, bloody stool, or black, tarry feces. Potential causes of such bleeding that can be identified with a colonoscopy include colon cancer and intestinal inflammation or damage.
- Bowel movement changes, such as pencil thin stools. Bowel movement changes can be caused by a variety of conditions from intestinal inflammation to colon cancer.
- Colon polyps, abnormal growths in the large intestine that can become cancerous. In some cases, polyps are first identified during another procedure called a barium enema and removed during colonoscopy.
- Colorectal cancer screening. A colonoscopy can identify and remove abnormal tissue and colon polyps before they have the chance to develop into cancer.
- Diarrhea. A colonoscopy can identify inflammation and infections.
- Diverticulosisand diverticulitis, intestinal pockets that can develop over time and become infected
- Inflammatory bowel disease, which includes ulcerative colitis and Crohn's disease
- Unexplained weight loss if the underlying cause has not been found through other, less invasive tests
© Copyright 2012 Health Grades, Inc. All rights reserved. This information is for educational purposes only and is not intended as a substitute for professional medical care. For specific medical advice, diagnoses and treatment, consult your doctor.