A flexible sigmoidoscopy is a test which allows a look at the lower part of the large bowel (Sigmoid colon). The endoscopist will use a flexible tube with a light at the end. The tube is passed through the rectum into the large bowel. The endoscopist gets a clear view of the lining of the bowel and can check whether or not any disease is present. The difference between a Flexible Sigmoidoscopy and a Colonoscopy is simply that a flexible sigmoidoscopy looks for the cause of rectal bleeding and any problems around the anus and lower colon. It doesn't travel as far as the Colonoscopy and requires slightly less bowel preparation.
Sometimes the endoscopist takes a biopsy – a sample of the lining for examination in the laboratory. A small piece of tissue is removed painlessly through the Colonoscope using tiny forceps.
It is also possible to remove polyps during the test. Polyps are small lumps on the bowel wall, which the endoscopist will want examined by the laboratory.
The procedure itself takes approximately 15 minutes, however you should expect to be at the clinic for 2-3 hours. This does vary from clinic to clinic and is dependent on whether you have sedation. The admitting nurse will be able to give you an estimated time on the day.