  Radiation therapy is an effective and widely accepted form of treatment for
many types of cancer that requires extensive computerized planning.
Unfortunately, current treatment planning systems have limited or no visual aid
that combines patient volumetric models extracted from patient-specific CT data
with the treatment device geometry in a 3D interactive simulation. We
illustrate the potential of 3D simulation in radiation therapy with a web-based
interactive system that combines novel standards and technologies. We discuss
related research efforts in this area and present in detail several components
of the simulator. An objective assessment of the accuracy of the simulator and
a usability study prove the potential of such a system for simulation and
training.
