Two presentations made at the CIRSE annual meeting have validated both virtual reality (VR) and simulation models as training mechanisms for interventional radiologists (IRs).
Dr Derek Gould, Liverpool University NHS Trust, UK, argued that IRs face training through an apprenticeship, which it is fraught with logistical and political problems. "While there are declining opportunities for apprenticeship training," stated Gould, "there exist a number of alternatives for acquiring basic skills."
He said, "It is clear that the virtual environment is set to become the new apprenticeship." He argued such environments allow the apprentice to deliberately make mistakes in safety and thereby understand the consequences of and ways of avoiding such errors.
To assess the validity of the virtual environment, Gould and his team investigated the human factors and instrument/tissue properties in interventional radiology procedures. They recorded IR procedures performed by masters and non-masters, which were then reviewed by an occupational psychologist. The procedure descriptions were then constructed, converted into a hierarchical task analysis and validated by subject matter experts (SMEs). The SMEs then derived indices (metrics) for performance assessment. The physics basis of simulation was investigated using calibrated fingertip force measurement pads, worn during IR needle puncture procedures in patients.
The results revealed that metrics were identified and shown to differentiate between masters and non-masters (time to perform a procedure, economy of movement). Study of needle forces during IR procedures in patients (eight male, two female) showed a range of 0.13 to 8.89 (mean 3.76 +/- 3.32) Newtons for arterial puncture.
Gould concluded that data can be derived and utilised for the development, validation and assessment for high fidelity, VR models which are of increasing relevance to interventional radiology models.
In comparison, Dr Steve Dawson from Massachusetts General Hospital (MGH), presented research purporting the views that advances in computing, haptics and graphics can be applied to medical education to change medicine's tradition of learning on humans.
Dawson, who works for The Simulation Group at MGH, commented, "Right now, we still use the same teaching model that Egyptians used 4,000 years ago", he says. "If I'm a doctor in a teaching hospital and a sick person comes in, I learn on that person. If I need to learn how to treat a particular disease and no one with that disease shows up, I'm out of luck. This system worked fine for all those years when there was no other way to teach young doctors, but we are at a crucial time in medical education, where revolutions in computing, mathematics, engineering and education surround us. Our challenge in medicine is to grab the best of these revolutions and create a new way of medical learning. But we need to do it carefully and we need to know that when we make a better way, it will work as well as, or better than, the old ways, because we can't go backwards," he commented.
Dawson said the hardest part of creating an effective simulator is to create a physics-based models of anatomy, blood-flow, instrument movement and tissue tool interaction. He also said that any simulator must have a strong education content ie. physicians must learn from using it and that it can be proved in a rigorous test.
Moreover, he stated that any system "must make it real" with full instrument selection and exchange, adding that good visuals were the easiest part of of a bad system. "Without physician involvement from first ideas through final validation, simulation designers may spend months or years in wasted effort. And before effective simulators are ready, rigorous scientific research has to be done, so that we don't just create elaborate video games and pass them off as medical training systems," he argued.
Dawson acknowledged that the simulation technology currently available is just the start of a long process and physicians need to stay involved with the R&D, establish a curricula, keep an eye on what is needed and recognise that progress will take some time.
To conclude, Dawson said simulation will provide an early focus on carotids (radiology, cardiology and vascular surgery), with additional focus on the renal, iliac, suprafemoral arteries and an eventual simulation package for the coronaries.
Dawson also development of the EVE Endovascular Training System, a new endovascular prototype for interventional training, which he believes is a quantum leap over current simulators. It offers both arterial and venous anatomy from the aortic arch to the superior vena cava, so that both arterial and venous interventions can be simulated. The level of detail in the anatomic model is much higher than presently available systems have, with 6,400 vessels represented. As with other systems developed by the research group, the EVE system will be physics-based, so that physiology, catheter/guidewire interactions and blood flow are all responsive to the manipulations performed by the user. The SIMGroup expects to begin field testing the system in spring 2006.
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