The diagnosis of colon disease usually begins with a complete medical history, family history, and a thorough physical exam. Two common diagnostic tests used to view the colon directly are colonoscopy and flexible sigmoidoscopy.
The diagnosis of colon disease usually begins with a complete medical and family history, as well as a thorough physical exam. The provider may ask a variety of questions about bowel habits, pain, other symptoms, diet, medications and conditions that run in your family.
The physical exam will include an assessment of the abdomen. This is where the provider presses or palpates the abdomen, searching for areas of tenderness or abnormal growths called masses. The exam may also include a digital rectal exam. To perform this test, the provider inserts a gloved, lubricated finger into the rectum to detect tenderness, blockage, or blood.
Based on the history and physical exam, specific tests may be recommended. Blood tests, like a complete blood count, or CBC, may be ordered. Your provider may also ask for a stool sample, which can then be tested for blood.
Two common diagnostic tests used to view the colon directly are colonoscopy and flexible sigmoidoscopy. Although the tests are very similar, colonoscopy examines the entire colon, while sigmoidoscopy examines only the lower third of the colon. The main differences between colonoscopy and sigmoidoscopy are that sigmoidoscopy is performed without sedation, requires a less rigorous preparation, and generally has fewer complications. However, colonoscopy provides a more complete view of the colon, and is considered by many the “gold standard” of colon screening.
Another form of colonoscopy is a diagnostic test called a virtual colonoscopy. The basic difference between virtual and conventional colonoscopy is how the provider sees inside the colon. Instead of using an endoscope, virtual colonoscopy uses computerized tomography, called CT, or magnetic resonance imaging, called MRI, to view the colon. Unlike traditional colonoscopy or sigmoidoscopy, virtual colonoscopy does not insert an endoscope into the anus. However, a small, catheter-like tube is inserted into the rectum. Air is pumped through this tube into the large intestine to give the provider a better view of the colon.
Along with CT and MRI, other imaging tests are also used to diagnose colon conditions. Your provider will discuss with you the current recommendations for screening based on your age and personal condition.
It’s important to remember colorectal cancer often has no symptoms, and that early screening for colon disease can save lives.