Flexible sigmoidoscopy is a procedure that enables your surgeon to examine the lining of the rectum and lower colon (bowel). It is usually done in a procedure room or in hospital. A lubricated soft, bendable tube about the thickness of the index finger is gently inserted into the anus (rectal opening) and moved into the rectum and the lower part of the colon.
Flexible Sigmoidoscopy is often done as part of a routine screening for cancer for patients over 50 years old, before some surgeries, or to evaluate the causes of symptoms (such as diarrhoea, bleeding, colitis, changes in bowel habits and, changes in stool form or colour). Flexible Sigmoidoscopy is also used as a screening tool for patients whose families have a history of colorectal cancer.
The rectum and lower colon must be completely emptied of stool for the procedure to be performed. One or two enemas prior to the procedure is all that is necessary, but laxatives or dietary modifications may be recommended by your surgeon in certain instances. Your surgeon or his/her staff will give you instructions regarding the cleansing routine to be used. If the area to be examined is not clear of stool the surgeon will not be able to perform an effective examination. Be sure to follow your surgeon’s preparation instructions.
Most of your medications can be continued as usual. However, the use of medication such as aspirin, Vitamin E, nonsteroidal anti-inflammatories, and blood thinners should be discussed with your surgeon prior to the examination. It is essential that you alert your surgeon if you require antibiotics prior to undergoing dental procedures, since you may also require antibiotics prior to sigmoidoscopy.
You will be given some light sedation during the procedure. The procedure is well tolerated and rarely causes discomfort. The inside of the colon has few nerve endings; therefore, it is unusual to feel the scope moving within the body. Air is injected to distend or widen the passage. This may cause a feeling of pressure, gassiness, bloating, or cramping during the procedure. You will lie on your side while the sigmoidoscope is advanced through the rectum and lower colon. The lining of the intestine is examined carefully. The procedure usually lasts for five to fifteen minutes. If there is extreme discomfort, you should tell your surgeon and the procedure will be terminated.
Your surgeon will explain the results to you and discuss any findings. You may have some mild cramping or bloating from the air that was placed into the colon during the examination. This should quickly improve with the passage of gas. You should be able to eat and resume normal activities after leaving the surgeon’s office or hospital. If your surgeon sees an area that needs more detailed evaluation during the procedure, a biopsy may be obtained and submitted to a laboratory for analysis. This is done by placing a special instrument through the sigmoidoscope to extract a tiny sample of the lining of the colon. This procedure is painless. If polyps or growths are found, your surgeon will usually request that you have a colonoscopy, which is a complete endoscopic examination of the entire colon. A colonoscopy is more suitable to remove polyps and enables the surgeon to check the remaining colon for any other polyps or lesions.
Flexible sigmoidoscopy and biopsy are safe when performed by surgeons with appropriate training and experience in endoscopic procedures. Complications are rare, however, they can occur. They include bleeding from the site of a biopsy or a perforation, which is a tear through the lining of the bowel wall. It is important to contact your surgeon if you notice symptoms of severe abdominal pain, abdominal distension, nausea, fevers, chill, or rectal bleeding equal to more than half a cup. Bleeding can occur up to several days after a biopsy.