Sigmoidoscopy
Sigmoidoscopy is a thorough examination of the last two feet of the lower colon. For patients who experience rectal bleeding associated with hemorrhoids, it may be used to rule out colon cancer, abnormal growths, and other conditions.
Causes and Symptoms of Hemorrhoids
Hemorrhoids are extremely common, as about half of the adult population in America will experience a hemorrhoid at some point in their lives. Hemorrhoids develop when increased pressure is exerted on the veins in and around the anal canal. Normally, the tissue surrounding the inside of the anus fills with blood to help control bowel movements. Hemorrhoids form when excessive pressure causes these veins to swell and stretch either into the anal canal (internal) or under the skin surrounding the anus (external.) Poor diet, lack of exercise and physical stresses are the most likely causes of hemorrhoids.
Rectal bleeding is a common symptom of hemorrhoids, as is pain and itching. However, rectal bleeding can also be associated with other serious conditions such as colon cancer, rectal cancer, and Crohn's disease. For this reason, patients who are over 40 with a family history of one of these conditions may need a sigmoidoscopy to confirm that hemorrhoids are the cause of their symptoms.
Understanding Hemorrhoid Sigmoidoscopy
Sigmoidoscopy is a thorough examination of the last two feet of the sigmoid colon. It is most commonly used to screen for colon cancer and it can be used to detect other abnormal growths such as tumors and polyps. A health care professional can also remove small growths and collect tissue samples with this test. Sigmoidoscopy requires the use of an enema or laxative to completely empty the colon before it is administered.
Flexible vs. Rigid
Sigmoidoscopy is performed using a sigmoidoscope, which is a lighted tube that may be rigid or flexible. A rigid sigmoidoscope is ten to twelve inches long and about one inch wide. It allows your health care professional to see into the rectum and a portion of the colon. A new device, called a flexible sigmoidoscope, a 24 inch long thin flexible tube which contains a tiny color video camera is now used. Using this instrument, your doctor can see around bends in the colon. It generally allows for a more comprehensive view of the lower colon and is more comfortable on the patient than the rigid scope.
Preparing for a Sigmoidoscopy
Although the precise preparations may vary, you may be asked to follow a liquid diet for a few days before the test and to avoid eating about twelve hours before the test. You also may need to have an enema the night before the test and another enema about an hour before the examination. If you think your condition is caused by hemorrhoids, you should also take care to avoid any straining while lifting or during bowel movements that may further irritate the sensitive tissue.
Performing the Sigmoidoscopy
You will be asked to disrobe from the waist down and place a drape over your waist. Your health care provider will then position you either on your left side with your knees drawn to your chest, or on your elbows and knees with your buttocks raised. Once you are in position, the practitioner will insert a gloved finger to check for tenderness and blockage. He or she may also evaluate any external hemorrhoids that may be present at this time.
The lubricated sigmoidoscope will then be inserted into the anus and moved slowly forward into the rectum and lower colon. You may feel some cramping and the urge to have a bowel movement while the scope is in the colon. You may also feel some slight pain and itching due to irritation of any hemorrhoids that may be present. Once the sigmoidoscope has been advanced as far as possible, your health care provider will slowly withdraw it while carefully examining the colon. The test usually takes about ten to thirty minutes, or slightly linger if tissue samples are also taken.
Results of the Sigmoidoscopy
A normal result of a sigmoidoscopy means the lining of the colon appears smooth and pink with numerous folds and that there are no abnormal growths, pouches, bleeding or inflammation present. Abnormal findings of sigmoidoscopy include hemorrhoids, polyps, tumors, ulcers, diverticulosis, or inflammation. If after performing this test, your health care provider can confirm that hemorrhoids are the cause of your symptoms, he or she may prescribe a conventional hemorrhoidal preparation or a medical procedure such as hemorrhoid surgery to remove the irritant.
Risks of Sigmoidoscopy
Sigmoidoscopy is a relatively safe test that rarely causes problems. There is a slight risk of colon infection associated with the test. There is also a rare possibility that the colon may be punctured or perforated during a sigmoidoscopy. This would cause severe bleeding and damage to the wall of the colon. However, this possibility is extremely rare (1 in 10,000).
