Colonoscopy is the examination of the large bowel, or colon by means of a highly sophisticated, flexible, fibre-optic instrument called a colonoscope. This enables the examiner to obtain a detailed view of the lining of the bowel and, when appropriate, to take small samples of the lining (biopsies). Colonoscopy is also a popular method used to remove small growths called Polyps. In conventional endoscopy treatment, the endoscope is passed through the mouth and throat into the oesophagus. During a colonoscopy, the endoscope is passed through the rectum into the large intestine (colon).
Before an endoscopy examination, a good bowel preparation is necessary to allow a clear view during the examination and it is most important to carefully follow the instructions given.
The examination typically takes 20-30 minutes and most patients need only come to the hospital as a day patient, returning home the same evening. Sedation is used so that patients will remember little to nothing about the procedure. The large bowel is examined with an instrument called a colonoscope (see photograph above). This allows the surgeon to examine the lining of the bowel, to take samples for further examination and, if present, remove growths called polyps.
After the colonoscope a rest for 3-4 hours allows the patients to sleep off the sedation following which they may have something to eat and drink before going home. It is most important however, to be accompanied home by a friend or relative and to observe the precautionary warnings enclosed in the documentation you will be given. By the following day you may expect to eat a normal diet.
It is quite normal for the bowel to take several days to regain its usual actions. If biopsies have been taken you may notice a few specks of blood but this should not concern you. Rarely bleeding may occur about 10 days after removal of a polyp. This is invariably self limiting and settles with rest, but do inform your own doctor immediately if the bleeding is heavy for it may be necessary to observe you in hospital for a day or two. Rarely perforation of the colon may complicate the procedure occurring in 1:500 to 1:1000 cases. If this does occur it may be necessary to perform an immediate operation to close the leaks in the bowel.
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