Various tests are used to screen for colorectal cancer, including FOBT, digital rectal examination, barium enema imaging, sigmoidoscopy, colonoscopy, and virtual colonoscopy. FOBT checks for blood in the stool, while a barium enema uses X-rays to detect abnormalities. Sigmoidoscopy and colonoscopy require colon cleansing and involve inserting a thin, flexible tube to view the colon, while virtual colonoscopy generates computer images.
There are several colorectal cancer tests that are commonly used to screen individuals for colorectal cancer. These include simple tests, such as the fecal occult blood test (FOBT), digital rectal examination, and barium enema imaging. Other complex colorectal cancer tests, such as sigmoidoscopy, colonoscopy, and virtual colonoscopy, provide the patient with more comprehensive screening.
A digital rectal exam is one of the most common of all colorectal cancer tests and is usually performed as part of a person’s physical routine. A doctor oils his glove, then inserts his finger into a patient’s rectum and looks for any abnormalities. This exam includes only the lower rectum and is not considered a comprehensive screening. If abnormalities are found, a doctor usually recommends that the patient undergo further tests.
The FOBT is a simple test that checks for signs of blood in a person’s stool. While not specific diagnostic, blood in the stool can indicate problems that require further evaluation. A FOBT is often used as a preliminary means of determining if more extensive testing is required.
Another type of test called a barium enema uses X-rays to detect abnormalities. Before the X-ray, a liquid solution of barium sulfate is placed into the patient’s rectum. The silver-white compound coats the inside of the lower gastrointestinal tract, making it easier to visualize polyps and other abnormal areas.
Sigmoidoscopy and colonoscopy are two more advanced types of tests for colorectal cancer. These tests are similar and both require a patient to prepare in advance by thoroughly cleansing his or her colon. Typically, a patient is given a strong laxative to use at home before the test so that the colon is completely empty when the test is given.
During a sigmoidoscopy, a sigmoidoscope, a thin, flexible tube, is threaded into the patient’s rectum and lower colon. The sigmoidoscope is lighted and typically has a lens attached so the doctor can see inside the rectum and lower colon. He may also have a tool attached to remove or biopsy any growths that are found during the procedure.
A colonoscopy is very similar to a sigmoidoscopy, except that the entire colon is viewed. The patient is usually sedated during the procedure. The instrument used, called a colonoscope, is very similar to a sigmoidoscope. The colonoscope generally has a tiny camera attached to the tip so that an image can be projected onto a video screen for the doctor’s evaluation.
One of the least invasive tests for colorectal cancer is virtual colonoscopy, also known as computed tomographic colonography. During this procedure, a specialized type of X-ray is used to generate images of a patient’s colon, and those images are used to create a detailed computer image that may show abnormalities. While less invasive than other colorectal cancer tests, this type of screening may not be as accurate as some of the other tests.
Protect your devices with Threat Protection by NordVPN
