Colonoscopy is an examination that evaluates the mucosa of the large intestine and is especially indicated to identify the presence of polyps, intestinal cancer or other types of changes in the intestine, such as colitis, varicose veins or diverticular disease.
This test may be indicated when the person has symptoms that may suggest bowel changes, such as bleeding or persistent diarrhea, for example, but it is also routinely needed for colon cancer screening for people aged 50 years or older, or earlier if there is an increased risk of developing the disease. Check out the symptoms of bowel cancer and when to worry.
In order to perform the colonoscopy, it is necessary to make a special preparation with adjustments in the feeding and use of laxatives, so that the intestine is cleaned and the alterations can be visualized. Generally, the exam does not cause pain as it is done under sedation; however, some people may experience discomfort, swelling or pressure in the abdomen during the procedure.
What is it for
Some of the key indications for colonoscopy include:
- Search for polyps, which are small tumors, or signs suggestive of colon cancer;
- Identify causes of bleeding in the stool;
- Evaluate persistent diarrhea or other changes in bowel habits of unknown origin;
- Diagnose colon diseases such as diverticulosis, intestinal tuberculosis, ulcerative colitis or Crohn's disease, for example;
- Investigate causes of anemia of unknown origin;
- Make a more detailed assessment when changes are found in other exams such as occult blood test in the stool or dubious images in the opaque enema, for example. Check out what other tests are indicated to detect bowel cancer.
During the colonoscopy examination it is also possible to perform procedures such as biopsy collection or even removal of polyps. In addition, the test can be indicated as a therapeutic method, since it also allows the cauterization of blood vessels that may be bleeding or even a decompression of intestinal volvo. See what intestinal volvo is and how to treat this dangerous complication.
Preparation for colonoscopy
In order for the doctor to be able to perform the colonoscopy and visualize the changes, it is necessary that the colon is completely clean, that is, without any residue of feces or food and for this, a special preparation must be made for the examination, which is indicated by the doctor or clinic conducting the examination.
Ideally, the preparation is started at least 2 days prior to the examination, when the patient can proceed to an easily digestible diet, the basis of bread, rice and white pasta, liquid, juices without pulp of the fruit, meat, fish and eggs cooked, and yogurt without fruits or pieces, avoiding milk, fruits, nuts, vegetables, vegetables and cereals.
A liquid diet is indicated in the 24 hours before the test, so that no residues are produced in the large intestine. It is also recommended to use laxatives, drink a solution based on Mannitol, a type of sugar that helps in cleaning the intestine, or even do a bowel washing, which is done according to your doctor's advice. Learn more about diet and how the menu is to prepare for colonoscopy.
In addition, some of the medications used may need to be discontinued prior to the examination, such as ASA, anticoagulants, Metformin or insulin, for example, according to your doctor's recommendation. It is also necessary to go with the exam because sedation may make the person drowsy and is not indicated to drive or work after the examination.
How is colonoscopy done?
A colonoscopy is done with the introduction of a thin tube through the anus, usually under sedation for better patient comfort. This tube has coupled a camera to allow visualization of the intestinal mucosa, and during the examination small amounts of air are injected into the intestine to improve visualization.
The patient is usually lying on his or her side, and as the doctor inserts the tube of the colonoscopy device into the anus, he may feel increased abdominal pressure.
The colonoscopy usually lasts between 20 to 40 minutes and after the examination, the patient should be in recovery for about 2 hours before returning home.
What is Virtual Colonoscopy
Virtual colonoscopy uses computed tomography to obtain images of the intestine, not requiring the camera colonoscope to capture images. During the examination, a tube is inserted through the anus that injects air into the intestine, making it easier to observe its interior and possible changes.
Virtual colonoscopy has some limitations, such as difficulty in identifying small polyps and the impossibility of biopsy, which is why it is not a reliable substitute for normal colonoscopy. Read more about this procedure in: Virtual Colonoscopy.
