“Virtual” colonoscopies done using a computer-assisted X-ray are nearly as accurate as the standard kind and may entice reluctant patients into having the embarrassing procedure, U.S. researchers said.
The first study into results of virtual colonoscopies paid for by insurance showed that only 6.4 percent of patients required follow-up with optical colonoscopy, which involves threading a tiny camera on a tube through the rectum and into the colon.
“Our positive experience with virtual colonoscopy screening covered by health insurance demonstrates its enormous potential for increasing compliance for colorectal cancer prevention and screening,” said Dr. Perry Pickhardt of the University of Wisconsin Medical School in Madison.
Colonoscopy is recommended for everyone every few years starting at age 50. The procedure can identify pre-cancerous growths and in many cases these polyps can be removed at the time of screening.
But many people are embarrassed to undergo the procedure, which can also be uncomfortable, although patients are almost always sedated.
Pickhardt’s team used three-dimensional computed tomography colonography, commonly known as virtual colonoscopy, to screen 1,110 adults with an average age of 58. The virtual procedure is noninvasive and involves passing the patient through a scanning machine.
They found large or medium polyps in 10 percent of the patients. Seventy-one, or 6.4 percent, of the patients had a second, standard colonoscopy, most on the same day.
The standard colonoscopy findings were the same as the virtual colonoscopy findings in 65 of the 71 patients, the researchers reported in the journal Radiology.
Safer, faster
If any polyps are found using virtual colonoscopy, they must be removed using a standard colonoscope.
Colorectal cancer is the second leading cause of cancer death in the United States, after lung cancer. The American Cancer Society predicts there will be 148,610 new cases diagnosed in 2006 and 55,170 colon cancer deaths.
Screening and removal of polyps can prevent the disease.
“Our goal is not to take patients away from existing strategies like optical colonoscopy but rather to attract those who are currently not being screened at all,” Pickhardt said.
“The advantages of virtual colonoscopy over optical colonoscopy at our institution are that it is safer, faster, less costly, more convenient, involves an easier bowel prep, and yet is just as effective for detecting important polyps and cancers.”
