With funding from the US Office of Naval Research (ONR) and other agencies, Professor Arie Kaufman, Chair and Leading Professor at the State University of New York (SUNY) Stony Brook Computer Science Department, has developed a procedure called Virtual Colonoscopy.
It is said to be an accurate, cost-effective, fast, non-invasive, patient-comfortable procedure for screening of colon polyps, the precursor of cancer.
In contrast, conventional colonoscopy is invasive with a risk of puncturing the colon and requires that the patient be sedated. The negative perception of this method and the reluctance of the general public to get screened play a major role in colorectal cancer being the second leading cause of cancer related death in America.
Virtual Colonoscopy is an alternative procedure which can identify colon polyps before cancer spreads, is patient friendly, and can be performed within 15 minutes with minimum risk.
ONR has supported Kaufman’s investigation of volumetric (voxel-based) modelling and rendering algorithms that comprise the techniques used to render the virtual colon and visualise it interactively in real time.
In Virtual Colonoscopy, a 40-second single-breath-hold computed tomography (CT) scan of the patient’s abdomen is taken. Volume visualisation is then used to virtually navigate within an automatically segmented and reconstructed 3D model of the colon, searching for polyps.
Research has led to the development of patented ‘electronic cleansing’ methods for removing residual stool from the colon in the 3D model to avoid the need for harsh bowel cleansing.
The visualisation software, running on a PC, reportedly allows physicians to interactively navigate through the colon. An intuitive user interface with customised tools supports ‘virtual biopsy’ to inspect suspicious regions.
Clinical studies demonstrated the effectiveness of the Virtual Colonoscopy in imaging and detecting polyps as small as 3 mm in diameter. The current procedure is being extended to interactive 3D virtual endoscopy for visualising the interior of other organs, such as the heart, arteries, lungs, and stomach.
The technology has been licensed to Viatronix Inc. (Stony Brook, NY), which has installed over two-dozen Virtual Colonoscopy V3D-ColonTM systems in the US, including National Naval Medical Centre – Bethesda, Walter Reed Army Medical Centre, and Naval Hospital – San Diego. These machines have already scanned over 1000 patients.
In addition to the medical application discussed here, Kaufman’s volume graphics algorithms have been widely used in scientific data visualisation and also to render battlefield scenes.