A colonoscopy (koe-lun-OS-kuh-pee) is a procedure that enables an examiner (usually a gastroenterologist) to examine inside of the colon (large intestine or large bowel). The colonoscope is a 4 foot long, flexible tube about the thickness of a pen with a camera and a source of light at its tip. The tip of the colonoscope is inserted into the anus and then is advanced slowly, under visual control, into the rectum and through the colon usually as far as the cecum, which is the first part of the colon. Usually, it also is possible to enter and examine the last few inches of the small intestine.
Colonoscopy is an examining process to be done on several of reasons. The procedure takes only 30 to 60 minutes only. Majority of colonoscopies are performed as part of screening programs to diagnose colon cancer. When done for other reasons, it is most often done to investigate the cause of blood in the stool, abdominal pain, diarrhea, a change in bowel habit, or an abnormality found on colonic X-rays or computerized axial tomography (CT) scan.
Patient should follow specific diet plan before the examination as your Doctor suggested. You should avoid taking solid food the day before exam. Drinks may be limited to clear liquids, plain water, tea and coffee without milk or cream, broth, and carbonated beverages.