A colonoscope is a type of endoscope (literally 'a tool to look inside the body') used to examine the interior lining of the bowel. The device itself is a long tube which is inserted into the bowel via the anus. It is equipped with a very small video camera and a light at the tip so that the bowel wall lining can be examined and also has some miniaturised surgical tools so that some procedures can be carried out at the same time, such as biopsies (the removal of tissue for analysis) and the removal of small polyps - small growths out from the bowel wall.

Colonoscopy is a 'minimally invasive' procedure - that is, no incisions are required as the colonoscope is introduced into the body through a natural opening - the anus. This means the body is placed under significantly less stress than is the case with conventional surgery, and as a result the procedure is quicker, recovery times are quicker and there are no scars to the body.

Often a colonoscopy will be recommended where...

  • A faecal occult blood test (a test for blood in the stool invisible to the naked eye) has come back positive.
  • There is a family history of cancer of the bowel.
  • There is bleeding from the anus / rectum.
  • The patient has had polyps removed in the past.

The day before the colonoscopy, patients must make sure their bowels are empty by taking special medication. The procedure itself is straightforward and is generally carried out under a mild sedative. It takes up to half an hour to complete and patients are kept under observation for a two-hour period afterwards.

After this, patients are free to return home, although due to the effects of the anaesthetic they should not drive themselves home and should not return to work that day.