Lower GI Endoscopy (Sigmoidoscopy or Colonoscopy)
MEDICAL ANIMATION TRANSCRIPT: A lower GI endoscopy-- also called colonoscopy or sigmoidoscopy-- allows your doctor to view the mucosal lining of your lower gastrointestinal tract. The procedure is used as a screening test in individuals with no symptoms, or to help diagnose unexplained abdominal pain, rectal bleeding, or a change in bowel habits. It is capable of detecting inflammation, infections, ulcers, diverticulosis, intestinal narrowing, colorectal polyps, cancer, or other problems that may be present. Before the procedure, you will need to undergo bowel preparation. Depending on the type of medication prescribed to you, you will start one to three days before the procedure. You will need to modify your diet as well as take medication, which will help to clear your bowels in preparation for the procedure. The procedure is performed using an endoscope, which is a long, thin, flexible tube with a light and a tiny video camera attached to the end. The camera transmits an image to a monitor. In a sigmoidoscopy, the endoscope only reaches to the top of the descending colon. In a colonoscopy, the endoscope reaches through the entire length of the colon to where it connects to the small intestine. The presence of the endoscope, and the air, may cause you to feel cramping, or pressure, and the need to pass gas. This is considered a normal part of the procedure. Your doctor may ask you to change your position slightly to help maneuver the endoscope more easily through the curves of your lower intestine. If you experience pain, tell your doctor immediately. In some cases, your doctor may find it necessary to take a biopsy. A biopsy helps distinguish between benign and cancerous tissues, and can help determine the cause of bleeding, inflammation, or diarrhea. Biopsies are often taken even when your doctor does not suspect cancer. If one or more polyps are discovered, your doctor will generally remove them in a procedure called a polypectomy. He or she will usually use a snare to remove the polyps and then cauterize their bases to control bleeding. At the end of the procedure, the endoscope will be removed from your colon. A sigmoidoscopy usually takes about 20 minutes, while a colonoscopy can take 30 minutes to an hour.