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Colonoscopy - virtual; CT colonography
How the test is performedPatients must follow a strict bowel-emptying procedure the day before, just as they would for a standard colonoscopy. The test is performed in the radiology department of a hospital or medical center. Unlike conventional colonoscopy, no sedatives are needed and no scope is used.
You will lie down on your left side on a narrow table that is connected to an MRI or CT machine. Your knees will be up toward your chest. A small, flexible tube will be inserted into your rectum. Air is pumped through the tube to make the colon bigger and easier to see. After this is done, you'll be asked to lie on your back.
Next, the table slides into a large tunnel through the machine, where x-rays create images of your colon. You must stay very still during this procedure, since movement can blur the pictures. You may be asked to hold your breath briefly while each picture is taken.
A computer combines all the images to form three-dimensional pictures of the colon, which are viewed on a video monitor.
Pictures are also taken while you lie on your stomach.
The exam takes about 20 minutes.
How to prepare for the testPreparations can vary, depending on your health care provider. Everyone undergoing any type of colonoscopy must completely empty their bowels before the exam. This may be done using an enema or laxatives combined with a liquid diet the day before the test. The bowel must be completely emptied until no solid matter remains.
Unfortunately, diarrhea is common during preparation. Drink plenty of clear liquids, such as apple juice and chicken broth, to avoid dehydration.
Make sure you tell your health care provider about any medications you are taking. You'll be told which you can take, and which you should temporarily stop. CT and MRI scanners are very sensitive to metals. Don't wear jewelry the day of your exam. You'll be asked to wear a hospital gown for the procedure.
How the test will feelThe x-rays are painless. Pumping air into the colon can create temporary cramping or gas pains.
Why the test is performedVirtual colonoscopy may be performed to:
- Diagnose colorectal cancer
- Examine those with a family history of colon cancer
- Follow up after an incomplete or failed colonoscopy
- Follow up after a previous finding of colon cancer or polyps
- Look for polyps
Normal findings are images of a healthy intestinal tract.
What abnormal results mean- Polyps
- Colorectal cancer
- Diverticulosis
- Lower gastrointestinal (GI) bleeding
- Tumor
- Inflammatory bowel disease
- Radiation exposure
- The medications to prepare for the test can cause nausea, vomiting, bloating, or rectal irritation.
Differences between virtual and conventional colonoscopy include:
- Both procedures can spot polyps that have reached a large, worrisome size. However, virtual colonoscopy is not as detailed as a conventional colonoscopy, and may miss polyps smaller than 10 millimeters in diameter or flat lesions.
- If a polyp is found with virtual colonoscopy, the patient must have a conventional colonoscopy to remove the abnormality. Conventional colonoscopy allows for the immediate removal of polyps.
- Virtual colonoscopy can view the colon from many different angles. This is not easy with conventional colonoscopy.
- Virtual colonoscopy uses no sedation, and patients are usually able to resume normal activities immediately after the test. Conventional colonoscopy involves sedation, and usually the loss of a work day.
Virtual colonoscopy is now one of the American Cancer Society's recommended screening tools for colon cancer.
ReferencesLieberman, D. Colonoscopy: as good as gold? Ann Intern Med. 2004;141:401-403.
Pickhardt P, et al. Location of adenomas missed by optical colonoscopy. Ann Intern Med. 2004;141:352-359.
Rosman AS, Korsten MA. Meta-analysis comparing CT colonography, air contrast barium enema, and colonoscopy. Am J Med.2007;120(3):203-210.e.4.
Van Dam J, et al. AGA future trends report: CT colonography. Gastroenterology. 2004;127:970-984.
Virtual colonoscopy. Med Lett Drugs Ther. 2005;47(1202):15-16.
What else can I help you with?
Can a virtual colonoscopy be as effective as a regular colonoscopy?
Studies in late 2003 showed that virtual colonoscopy was as effective as colonoscopy for screening purposes and it offered the advantage of being less invasive and less risky. However, many physicians were unwilling to accept it
Does Medicare pay for a virtual colonoscopy?
A virtual colonoscopy utilizes a CT scanner to picture the colon and rectum from outside the body. Medicare doesn't cover virtual colonoscopies, in view of a survey of accessible evidence.
Where to get virtual colonoscopy?
Main Street Radiology in Flushing advertises virtual colonoscopies. I have not been there.
What is the procedure of virtual colonoscopy?
Virtual colonoscopy is a procedure used to examine the large bowel for polyps and signs of cancer. It‰Ûªs also called computerised tomography (CT) colonography. It‰Ûªs done using a CT scanner, which uses X-rays to produce three-dimensional images of your bowel.
Why might bowel preparation become obsolete?
Computed tomography (CT) colonography (sometimes called virtual colonoscopy) has shown itself to be as accurate in diagnosing colorectal tumors as optical colonoscopy.
How do you set the centerline with auto level?
You set the centerline with auto level by making use of the virtual colonoscopy.
What are some problems with a virtual colonoscopy?
some patients might still require the regular colonoscopy as a follow-up to the virtual procedure if a polyp or abnormality is found that requires biopsy.
Is a virtual colonoscopy as effective as a traditional one?
Virtual colonoscopy (http://www.laendo.net/educational-articles/english-educational-articles/143-virtual-colonoscopy.html) is essentially an x-ray examination using CT scan. Using a computer X-ray image creates an image of colon and any lesion that may be associated with the colon. It usually can detect problem that is larger than 1cm. Additionally, flat lesion are difficult to detect. Moreover, there may an additional risk of ionizing radiation that may predispose one to undesired risk of developing cancer later on. Finally, if a lesion is found, one would still have to undergo colonoscopy to either take a close look, take a sample or remove the lesion. As a result, despite conceptual appeal, virtual colonoscopy is not frequently utilized. If you are referring to a Capsule Endoscopy which is a procedure where you swallow a small camera (pill) and pictures of your intestinal tract are recorded every 15 seconds then reviewed by doctors the next day, then YES it is a very useful tool and a definite advance in the arsenal of medical devices used to diagnose Intestinal disease.
Can colon cancer be detected without a biopsy?
If suspicious growths are observed, tiny biopsy forceps or brushes can be inserted through the colon and tissue samples can be obtained. Small polyps also can be removed through the colonoscope.
What prevents cancer of the colon?
Here some of the medical and diet preventions for colon cancer. Annual fecal occult blood testing Flexible sigmoidoscopy every five years Colonoscopy every 10 years Virtual colonoscopy (CT colonography) every five years Stool DNA testing - though this is a new screening approach and it's not clear how often it should be repeated Stop smoking Eat a variety of fruits, vegetables and whole grains. Exercise most days of the week Maintaining a healthy weight.
Is there a game with a virtual house that you can decorate and have a virtual avatar?
sims is a game that you can have a virtual house that you can decorate and have a virtual avatar .
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Find a virtual psychic to read your virtual memory.
