NEW YORK, May 08 (Reuters) -- A new method for finding cancer in the colon may bring virtual reality to medical diagnosis, according to radiology researchers.
Called virtual colonoscopy, it provides three-dimensional x-ray computed tomography (CT) scans of the abdomen to enable doctors to "fly" through the colon, much like a video game. The technology is less invasive than standard colonoscopy, and avoids the need for sedation during the procedure.
"Virtual colonoscopy is an evolving technology that will one day be a successful means of screening for colon cancer," says radiologist Dr. Clive Kay, visiting associate professor at the University of South Carolina College of Medicine in Charleston.
For patients, the procedure takes no more than a few minutes, compared with anywhere from 10 minutes to an hour for standard colonoscopy. The patient lies on a CT scan table and the colon is filled with air through an enema tube. The abdomen is then scanned.
Computerized technology then reconstructs the CT images of the abdomen into a "virtual" presentation of the colon, allowing the doctor to navigate through it electronically while viewing a computer monitor.
In standard colonoscopy, the colon (the large intestine) is examined by means of a long, flexible, fiberoptic viewing instrument passed into the colon through the anus while the patient is lying down, lightly sedated.
In a study of 33 adults, 28 colon polyps were identified by the conventional method. These study participants then underwent virtual colonoscopy, and that procedure identified most polyps that were at least 11 millimeters in size. It erroneously identified six polyps that were not present.
The researchers also estimate that virtual colonoscopy will be less expensive, about half the cost of the conventional method, which runs to about $1,000.
Kay points out, however, that further improvements must be made to the new technology before it can be used routinely. For example, the reconstruction of the CT images can take 30 to 45 minutes, he says.
In addition, the researcher notes that virtual colonoscopy has not yet been tested against standard colonoscopy on a large scale -- and that kind of study is necessary before it can be considered a viable screening alternative for colon cancer, he explains.
But the current study demonstrates the early potential of the technique, Kay says. "Our initial results show that virtual colonoscopy is technically feasible and capable of detecting the majority of lesions larger than 1 centimeter in size," he adds, pointing out that the technique may be able to pick up smaller polyps with further developments in computer software.
