Page 409 - Biomedical Engineering and Design Handbook Volume 2, Applications

SURGICAL SIMULATION TECHNOLOGIES 387

models of computation (e.g., differential equations, finite state machines, and hybrid systems). The
simulator and the application interfaces need to have support for hybrid models of computation, that
is computation of continuous and discrete deterministic processes, and stochastic processes, which
can be used to model basic biological functions.

Support for Parallel and Distributed Simulation. In a surgical simulation, software modules
numerically simulate the physics of a target environment. Highly accurate simulations for surgical
planning and compelling virtual environments for training typically require extensive computation
available beyond basic desktop computers or single-processor workstations. It is therefore necessary
for the simulation framework to support parallel and distributed simulations. Beyond just parallel
processing, development of network-enabled virtual environments is desirable to extend the accessi-
bility of surgical simulations and to allow computation to take place in existing computing facilities
while supporting planning and training from a variety of locations. This would allow sharing of
computational resources and ease the logistical requirements for deploying virtual environment-based
simulators.

Validation. Validation of the models and the underlying empirical data is a basic requirement for
reusability of the models.
Customization with Patient-Specific Models. In surgical planning and preoperational rehearsals,
it is necessary to use patient-specific models during simulation. Therefore, the models in the simu-
lation need to be customizable. This ties to the open architecture design of the simulation framework.
The open architecture approach should allow loading and working with custom data sets generated
by third parties.
There are several open source surgical simulation frameworks available, including, SPRING, 32
78
GiPSi, and SOFA. 79

13.4 CONCLUSION

Very significant technical and practical challenges need to be overcome for widespread adoption of
virtual environment-based simulations in surgical training. Commercial success of this technology
requires a successful business model which combines technological innovation with medical needs
and practical realities of existing medical education system. An important requirement is the devel-
opment of simulation systems together with an innovative education curriculum that will incorporate
the system rather than focusing on development of individual stand-alone systems.

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