Colonoscopy Going 3-D
Screening for colon cancer is a must. It's one of the most curable cancers if detected early, and one of the deadliest if it goes undetected for too long.
Now, the latest in computer imaging is holding out hope for a future screening method that's quicker, more accurate and less invasive than the traditional colonoscopy, medical correspondent Dr. Emily Senay reports.
Images created by a CT scan and a sophisticated computer program show a virtual reality look inside the colon. It's proving to be an effective way for doctors to find polyps that can progress to colon cancer.
Dr. Robert Shapiro a radiologist at Mount Sinai Medical Center in New York City explains, "Now we can obtain a very accurate 3-D image, which gives you pictures that look virtually identical to a real colonoscope. This is done, of course, without actually placing a scope into the patient."
Tuesday's study in the New England Journal of Medicine finds virtual colonoscopy is as good - if not slightly better - at spotting potential cancer than traditional colonoscopy. A high-tech computer program makes this possible.
Comparing images Dr. Shapiro explains, "The image in the upper right hand is the two-dimensional CT image, and you can see it's not nearly as graphic. The image on the bottom is the 3-D or virtual colonoscopy image and this image is an accurate computer representation of the inside of the colon. If there's an area of interest, you can stop the scanner and rotate to look around."
The downside is that if a suspicious polyp is found using virtual colonoscopy, the patient still requires a traditional colonoscopy for definitive diagnosis.
But because virtual colonoscopy is less invasive, the hope is that more people will be screened.
Dr. Shapiro says, "The patient doesn't have to have any needles; there's no sedation or analgesia involved in the exam. When the patient's done, there's no recovery afterwards so it's a much simpler and probably better tolerated test."
Colonoscopy candidate Abe Abuchowski says, "You just pick a morning or afternoon and go and have it done and right afterwards you're back at work again. It's much easier than spending the day being anesthetized and feeling groggy."
Tuesday's study compared the virtual colonoscopy with a traditional colonoscopy and found the results to be practically identical. Many doctors believe that we will be seeing more of this technique in the future - and that's a good thing, since it's estimated that many people avoid screening because of the dreaded colonoscope.
The hope is that if doctors can rule out the people who don't need further diagnosis, the number of more invasive procedures will be greatly reduced.
Right now, the technique is prescribed only for people who for some reason can't have a regular colonoscopy. More studies are needed to determine when and how virtual colonoscopy might be incorporated into routine screening.