During a colonoscopy, physicians utilise a flexible scope equipped with a fibre-optic camera to look for indications of cancer. To be certain of their diagnoses, they often must perform biopsies by guiding small sampling tools through the scope and into the colon to take tissue samples. If a cancerous or pre-cancerous growth, called a polyp, is detected, a physician can remove it using a technique called polypectomy, during which a snare is guided through the scope and looped around the polyp. An electrical current in the snare then cuts and cauterises the base of the polyp, allowing for removal without serious bleeding.
In Immersion Medical's simulations, doctors view a realistic three-dimensional model of the colon that visibly reacts to scope movement. The feel of performing procedures is provided by Immersion TouchSense technology, which reproduces the tactile sensations of scope resistance, surgical tool manipulation tissue stretching and difficult colon loop navigation. Each computerised patient audibly responds to users' actions by expressing discomfort or pain. At the end of the simulation, the system generates a detailed performance evaluation for review by users and supervisors.
Both the biopsy and polypectomy software modules run on the company's AccuTouch Endoscopy Simulator, which mimics the look, sound, and feel of performing a variety of minimally invasive procedures. The new simulations incorporate advances in physiological modelling and force-feedback, allowing physicians to feel the sensations of navigating colonoscopes and manipulating small surgical tools through the scopes. This allows doctors to safely practise, refine, and measure vital techniques without putting patients at risk.
"The simulation enables us to teach students concepts which are difficult to get across in a lecture. When trainees use the system, they apply their abstract knowledge in a realistic and interactive environment", explained Jacques Van Dam, M.D., Ph.D., Stanford University School of Medicine. "More importantly, they get to make their mistakes on a computer model, not a patient. Their strengths and weaknesses can be assessed objectively before they perform an actual procedure, and their training needs can better be identified. With this system, we can teach without risk, and we will be able to objectively measure clinician competence."
In addition to the colonoscopy modules, the AccuTouch Endoscopy system runs simulations for flexible sigmoidoscopy, which is also used for colorectal cancer screening, and flexible bronchoscopy, which is used to diagnose a variety of lung diseases. Immersion Medical also produces simulations for a wide range of vascular access and endovascular procedures. Approximately 500 Immersion Medical simulators are used in hospitals, universities, and medical schools worldwide.
"Our continued advancements in medical simulation allow doctors to gain invaluable experience before coming into contact with patients", stated Greg Merril, founder of Immersion Medical. "There is an immense demand for safety in medicine, so we are working to simulate as many procedures as possible, and the end is nowhere in sight." The biopsy module is currently available for Immersion Medical's AccuTouch Endoscopy Simulator. The polypectomy module is expected to be available in late August. More news about Immersion Medical's simulation software can be found in the VMW July 2001 article Simulated colonoscopy training likely to stimulate early detection of colorectal cancer.