aehrc.com - Australian e-Health Research Centre

In Australia, colorectal cancer is the most commonly reported cancer affecting both men and women. It is the third most common cause of cancer related deaths with an increasing risk profile from age 43 onwards. Current rates indicate that one in 22 Australians will develop colorectal cancer within their lifetime, one of the highest rates in the world.

Unfortunately few, if any symptoms are exhibited until the cancer has reached a relatively advanced stage, but treatment and survival rates improve significantly with early detection. Steps have been taken by the Department of Health and Ageing to trial programs for early detection. The Australian National Bowel Cancer Screening program is currently offering faecal occult blood tests (FOBT) to Australians in specific age groups, with positives usually referred for Colonoscopy. To ensure that support services, including Colonoscopy, can handle increased demands from positive screening results, the program is currently offering screening to an initial limited range of age groups.

Colonoscopy is a difficult procedure to master with literature indicating that an excess of 100 clinical cases are required to reach an expert level. In Australia, due in part to the lack of high fidelity virtual training systems, training occurs on real patients. Trainee involvement in the operating theatre has a significant impact on procedure times and subsequent increased costs, as well a greater risk of minor adverse effects for patients. Unfortunately, literature indicates that post procedural dissatisfaction associated with trainee involvement directly correlates to a reluctance to return for repeat screening.

The procedure itself involves a bowel preparation followed by the insertion of a long, flexible endoscope into the patient's rectum and careful navigation through to the caecum. The clinician then slowly withdraws the colonoscope and performs a careful lumen inspection. Failure to reach the caecum can result in the need for costly follow up procedures which may include Virtual Colonography via Computed Tomography.

Fig 1: Integrated advanced surgical simulation software with a novel haptic device allowing interaction with the virtual colon using a modified clinical colonoscope; developed in collaboration with Ecole Polytechnique Federale de Lausanne (EPFL).

To address the increasing demand for high quality Colonoscopy services in Australia, the CSIRO Preventative Health National Flagship is funding development of a patient-free Colonoscopy Simulator, under development at the Australian e-Health Research Centre. The project aims to produce a high fidelity simulation which not only provides photo-realistic visuals from the perspective of the endoscopic camera, but allows interaction with the virtual training environment via a clinical endoscope and a device capable of rendering force feedback to the trainee. The novel haptic device has been developed collaboratively by a team at Ecole Polytechnique Federale de Lausanne in Switzerland.

Through the development of high fidelity mathematical models of the colon, meso-colon and the clinical endoscope, researchers at the AEHRC are attempting to simulate the physics of the Colonoscopy procedure. The huge benefit of this approach is that advanced techniques, including endoscopic loop reduction can be instructed in an immersive environment where forces are calculated through the interaction between the computational models.

Fig. 2:Intubation of a dynamic colon with realistic force feedback.

The focus of the project initially has been to simulate the physics of colonic intubation with the aim of improving caecal intubation rates and patient safety. The ability to accurately simulate endoscopic loop formation and subsequent reduction techniques will allow advanced navigational techniques to be instructed without discomfort or risk to patients. Development of a database of anatomically accurate, 3D colon models and cases of varying clinical difficulty, coupled with realistic pathologies and photo-realistic rendering has the project well placed to cater for the future off-patient training needs for Colonoscopy in Australia.

Fig. 3: Advanced physical models of the colon and colonoscope for real-time interactions and forced calculations based on endoscopic looping.

Last Updated on Wednesday, 21 September 2011 14:28