A sigmoidoscope is used to view the inside of the rectum and lower colon. A finger-sized thick tube with a camera at the end is inserted from the rectum, and images of the inner wall of the rectum and part of the colon can be seen on the monitor. It can be used to take a biopsy of the polyp or tumor and remove some polyps. However, a colonoscopy needs to be done to view the whole colon and remove all polyps or tumors. It is fairly safe but has a small risk of bowel tear, bleeding, and infection.
A colonoscope is similar to a sigmoidoscope but is longer and is used to examine the inner wall of the whole colon. It is inserted from the rectum, and the doctor can see the images of the entire colon on the monitor. Special surgical tools can be passed through the colonoscope to take a biopsy and remove polyps. Sedation is required. There is a small risk of bowel tears, bleeding, or infection after the procedure. It’s important to note this is the only colorectal prevention strategy offered.
This is the computed tomography scan of the colon. The person is asked to lie on a table of the CT scanner, which takes cross-sectional images of the colon. It is a non-invasive technique and does not require sedation. If any abnormalities are found, a colonoscopy needs to be done to remove the polyps or tumors.
A small tube is inserted in the rectum, and barium sulfate, a white chalky liquid, and air is pumped into the colon. The barium suspension lines the outer walls of the colon. X-ray images of the colon are then taken to reveal abnormalities on the inner wall of the colon. If any abnormalities are found, a colonoscopy needs to be done to remove the polyps or tumors.
These are done with the fecal sample and are totally safe. Fecal tests may not give confirmatory results but may suggest abnormalities in the gastrointestinal tract, warranting further tests. A colonoscopy needs to be repeated if results are positive, indicating the presence of cancerous growth in the colon. There are three types of fecal tests:
- Fecal occult blood tests detect blood in the feces that is not visible to normal eyes through a chemical reaction.
- Fecal immunochemical tests detect blood through a specific immunochemical reaction of a protein in the blood and can detect hidden blood.
- Stool DNA tests look for certain abnormal DNA genes in the cells shed from cancerous outgrowth or polyps in the stool sample.
Enteroscopy is a procedure to examine the upper intestinal tract. It will allow your doctor to see further down into the small intestine than an upper endoscopy.