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New study offers virtual look at colon by Cindy Abole Public Relations It isn't writer Isaac Asimov's view of exploring the human body as described in his science fiction classic, Fantastic Voyage, but it certainly comes close.   Using advanced state-of-the-art screening equipment, physicians and specialists are taking virtual reality tours inside their patients. Their getting a look inside the hidden recesses of the inner ear, colon and blood vessels leading to the heart.    At MUSC's Digestive Disease Center and Department of Radiology, radiologists are able to view the colon to help detect small polyps or growths that often leads to colorectal cancer.      Colorectal cancer is the third most common cancer affecting men and women in the United States. Last year, more than 130,200 cases of colorectal cancer were reported. Thanks to the success of increased screenings and polyp removal, this form of cancer has shown a marked decline especially within the last decade.   But improved screening techniques, like virtual colonoscopies, have allowed specialists to look closer at polyps, six mm or larger, along the bowel lining. The comparisons of both techniques will help determine the effectiveness of this test and future use as an accurate screening test for colon and rectal cancer.   “We hope the study will show that virtual colonscopy can be used as a screening tool in the detection of colon polyps and prevention of colon cancer,” Susan Ackerman, M.D., assistant professor of radiology. Ackerman works with fellow radiologist Ranjit Rajah, M.D., as co-investigators of the study.   The multi-center study is sponsored under a Department of Naval Defense grant hosted by Digestive Disease Center director Peter Cotton, M.D., FRCP. It involves 1,000 patients in more than 10 research sites across the country. MUSC principal investigator Rig S. Patel, M.D., assistant professor of medicine is the gastroenterologist involved in the study.   The 30-minute virtual procedure requires no sedation, offers minimum risk and is relatively quick compared to the 45-minute conventional test. For the study, patients receive both a virtual 3-D CT scan and conventional colonoscopy. To prepare for both tests, the patient drinks a bowel prep drink the evening prior and an additional glass three hours before the virtual test. Using a small rectal catheter, a technician inflates the bowel with a small amount of carbon dioxide to allow the CT scanner to take pictures inside the colon.          During the process, more than 800 pictures are transferred from the CT scanner to a special archival computer system that  reads and restores the images into a 3-D format for viewing. Its results equal a fly-through rendering of the colon. Although the images may take an hour to restore, the radiologist records data and answers questions about the procedure.    According to Ackerman, the results are sealed in an envelope and sent along with the patient to the Digestive Disease Center. During the colonoscopy, the gastroenterologist compares his/her results with information from the virtual portion.      “As technology expands, this indeed, is really what the future is all about,” Ackerman said. "Tests can be done more efficiently and accurately.”                                                Recruiting study patients has not been an easy task. It is research nurse coordinator Melinda Lewin's job to educate physicians and staffs about the study and recruit patients who are already scheduled for a colonoscopy but are willing to give up their time and undergo additional testing.    The study is open to men and women age 50 and older. Study patients must not have had colon surgery or a colonoscopy within the last three years. Individuals diagnosed with familial adenomatous polyposis (FAP) or hereditary non-polyposis colon cancer cannot participate.   The grant will cover the costs of the virtual test and readings, however, patients must be able to pay for the colonoscopy.   “Some patients don't want to participate in anything requiring extra effort or time,” Lewin said. “But some patients are understanding and willing to help out. They realize the value of having both tests and want to participate.”   Challenging to patients who undergo these screenings is the fact many managed care organizations fail to cover the costs of colonoscopies and other preventive screening tests for patients. These costs are usually covered for patients who present colorectal symptoms or have a family history of the disease. Unfortunately, the price for this brand of prevention is an out-of-pocket expense.    “I'm a big believer in preventive care,” Ackerman said.  “I'd like to see insurance companies be more supportive in covering colonoscopies and other preventive tests. They may be paying more money initially, but they're actually spending less in the long-run for overall care.”   Results from both the virtual test and conventional colonoscopy will be shared with the patients. Although the outcome of the study is incomplete, there is hope that virtual colonoscopies will provide a less invasive means for screening of colon cancer.   “The colonoscopy has long been recognized as the gold standard test for detecting colon cancer,” Lewin said. “This is a chance to apply newer technology to continue saving lives.”   For more information about the virtual colonoscopy study, contact Lewin at 792-7856.