Colonoscopy to Diagnose Colon and Bowel Disease Shown Accurate
A study on Virtual colonoscopy was published in Wednesday’s issue of New England Journal of Medicine. It’s the largest study to estimate the accuracy of the technology; the research was sponsored by the National Cancer Institute and had 2,600 men and women tested at 15 medical centers. Dr. Daniel Johnson of the Mayo Clinic in Scottsdale, Arizona and colleagues are the ones who initiated and took care of the study.
Colon cancer is the third most common and second most deadly cancer in the United States. Screening for polyps is recommended at age 50, but traditional colonoscopies are so unpleasant that many people avoid them.
Traditional colonoscopies are performed by gastroenterologists using a flexible tube that is passed through the bowel. A device on the end of the tube can remove polyps for testing right then and there.
Virtual colonoscopy (VC) on the other hand, is a not so very old medical imaging procedure which uses x-rays and other machines and computers to produce three-dimensional images of the colon (large intestine) from its lowest part, called the rectum up to the lower end of the small intestine. VC is more comfortable than conventional colonoscopy for some people because it does not use a colonoscope. As a result, no sedation is needed, and the patient can return to his/her usual activities or go home after the procedure without the aid of another person.
It was recommended for anyone who needs screening colonoscopy. While the test still requires what doctors politely call "bowel preparation," the new technology is much easier and more comfortable for patient.
Participants underwent a virtual colonoscopy followed by a standard colonoscopy. Researchers found the virtual colonoscopy is actually very accurate, detecting 90 percent of polyps 10 millimeters or more in diameter. Problems occur though once the polyps have a smaller diameter. The 10 millimeter polyps progress to cancer at a rate of 1 per cent every year. Johnson and colleagues note that fewer than 2 per cent of polyps smaller than 5 millimeters have features that suggest they are precancerous. Should polyps be found during a VC, any growth will eventually be removed during the classical colonoscopy procedure. So the old methods cannot be left behind.
Regarding the VC, Dr. Durado Brooks, director of prostate and colorectal cancer for the American Cancer Society explained the following: "It will miss some abnormalities, but even colonoscopy is not a perfect tool. Studies of back-to-back colonoscopy show miss rates of between 2 and 11 percent.”
However Johnson admits that radiologists require specialized training and experience before they're ready to perform screening CT colonography. But he says that kind of training is readily available.
Colonoscopies cost up to $3,000. The X-ray test costs $300 to $800. All in all, the procedure is used to diagnose colon and bowel disease, including polyps, diverticulosis and cancer.
Colon and bowel disease:
The colon and the rectum are the final sections of the large intestine. In the United States, approximately 150,000 people are diagnosed with colorectal cancer every year and of these, approximately 55,000 will die of the disease. Cancer of the colon is the second leading cause of cancer death in the United States. Most experts agree that it is preventable.
Risk factors for the development of colorectal cancer include a low fiber diet, a family history of colorectal cancer, inflammatory bowel disease, multiple polyps (small lesions along the membrane of the colon or rectum--these can be hereditary or non-hereditary) and a previous history of colorectal cancer or adenomatous polyps (growths that develop on the membrane of the large intestine). But, the majority of all colorectal cancers arise in patients without any known risk factor. The incidence of the disease increases with age. Colorectal cancer develops from polyps, which if removed early in their growth, will never progress to invasive cancer.
What is a colonoscopy?
A colonoscopy allows a doctor to look inside the entire large intestine. The procedure enables the physician to see things such as inflamed tissue, abnormal growths, and ulcers. It is most often used to look for early signs of cancer in the colon and rectum. It is also used to look for causes of unexplained changes in bowel habits and to evaluate symptoms like abdominal pain, rectal bleeding, and weight loss.
The modern colonoscope is an exceptional examination device. It consists of a tiny video camera attached to a flexible tube which is no thicker than your index finger. It is inserted into the rectum of a patient under mild sedation and a perfect picture is shown on a television screen.
A color photograph can be taken at any time during the procedure. Colonic conditions can then be diagnosed and minor surgery can be performed through the colonoscope.
To allow a clear view of your bowel, you will be asked to drink a special mixture on the day before your procedure. You will also be advised about what you can eat and drink prior to your admission.
Possible complications or risks of colonoscopy:
Colonoscopy is generally a safe procedure. As wth any medical procedure, however, there are some risks associated with the procedure and with the sedation used.
Perforation and bleeding are the most common of the major complications associated with colonoscopy. Perforation is a tear through the wall of the bowel that may allow leakage of intestinal fluids. Perforations are generally treated with hospitalization, antibiotics, and possible surgery. As mentioned, another possible complication is bleeding, usually at the site of a biopsy or polyp removal. Most cases of bleeding stop without treatment or can be controlled at the time of the procedure. Rarely, blood transfusions or other treatments may be required to stop the bleeding. There is also a risk of having a reaction to a sedative or antibiotic given during the exam. In most cases, medications are available to counteract this reaction.
Although complications after colonoscopy are rare, they can be serious and life-threatening. It is important for you to be aware of early signs that something might be wrong. You should contact your doctor if you feel severe abdominal pain, dizziness, fever, chills, or rectal bleeding after the colonoscopy.