Colonoscopies and sigmoidoscopies are crucial for the detection of cancerous polyps and many other abnormalities. Our physicians are all board-certified in gastroenterology, and highly trained in performing colonoscopies and sigmoidoscopies.
Read our FAQs to understand what to expect during either of these procedures:
A colonoscopy is an exam that enables your doctor to examine the lining of your large intestine for abnormalities by inserting a flexible tube into your anus. This tube, called a colonoscope, slowly advances into the rectum and colon. A colonoscope has its own lens and light source that allows your doctor to view images on a video monitor.
Colonoscopy may be recommended as a screening test for colorectal cancer Colorectal cancer is the third leading cause of cancer deaths in the United States, and is a highly preventable form of cancer. A colonoscopy may also be recommended by your doctor to evaluate for symptoms such as bleeding and chronic diarrhea.
The colon must be completely clean for the procedure to be accurate and comprehensive, so be sure to follow your doctor's instructions carefully. In general, the preparation consists of:
Most medications can be continued as usual, but some can interfere with the preparation or the examination. Be sure to inform your doctor about any allergies you have to medications.
Tell your doctor if you’re taking:
You will lie on your side or back while your doctor slowly advances a colonoscope along your large intestine to examine the lining. Your doctor will examine the lining again as he or she slowly withdraws the colonoscope. The procedure itself usually takes less than 45 minutes, although you should plan on two to three hours for waiting, preparation and recovery.
In some cases, the doctor cannot pass the colonoscope through the entire colon to where it meets the small intestine. Your doctor will advise you whether any additional testing is necessary.
A colonoscopy is well-tolerated and rarely causes much pain. You might feel pressure, bloating or cramping during the procedure. Typically, your doctor will give you a sedative or painkiller to help you relax and better tolerate any discomfort.
If your doctor thinks an area needs further evaluation, he or she might pass an instrument through the colonoscope to obtain a biopsy (a small sample of the colon lining) to be analyzed. Biopsies are used to identify many conditions, and your doctor will often take a biopsy even when they don't suspect cancer. Your doctor might also find polyps (usually benign growths) during colonoscopy, and he or she will most likely remove them during the examination. Because cancer begins in polyps, removing them is an important means of preventing colorectal cancer.
Colonoscopy and polypectomy are generally safe when performed by doctors who have been specially trained and are experienced in these procedures.
A sigmoidoscopy is very similar to a colonoscopy, but it is less invasive. It lets your doctor examine the lining of the rectum and a portion of the colon by inserting a flexible tube (about the thickness of a finger) into the anus and slowly advancing it into the rectum and the lower part of the colon. Sedation is usually not needed.
A colonoscopy examines the entire colon and the screening is done every 10 years. A sigmoidoscopy looks at only the lower part of the colon, and the screening is done every five years.
In general, preparation consists of one or two enemas. Alternatively, your doctor may advise you to take laxatives and make dietary modifications as well. Sometimes, no special preparations are required. Follow your doctor’s instructions carefully to ensure accurate results.