Re-Assignment of Physical and Physiological Attributes to the Visible Human

Gregory L. Merril, Dwight A. Meglan, Ph.D., Gerald A. Higgins, Ph.D.

HT Medical, 6001 Montrose Rd, Suite 902, Rockville, Maryland 20852

Although the airline industry has used flight simulators for many years, difficult technical challenges have limited the use of computer-based simulation technology in medical education. The computer-based models in a flight simulators are less technically challenging to implement than a surgical simulator; the terrain of the ground is usually fixed and rigid, and an airplane simply moves through a chosen path above this terrain. A surgical simulator involves more complex behaviors. The organs of the body must be interacted with, and they must flex, be able to be cut and then re-attached. Simulated organs in the body must be programmed with physiological behaviors and basic principles of physics so they respond appropriately when they are cut, tugged, and stretched.

Over the last five years technology has been developed which incorporates the visual, physical/behavioral, and tactile realism necessary for life-like surgical simulation. HT Medical's software allows for the creation of virtual tissues and organs which not only look realistic, they also behave in life-like appropriate ways -- they react to gravity, they have inherent behaviors including involuntary muscle contraction, they bleed when cut, and when you touch them can feel them deform in you forceps.

Only those virtual environments that offer sufficient realism constitute a commercial viable alternative to established practice on cadavers, animals and patients. Realism in the context of virtual environments for medical training relates to how the anatomical structures appear, how life-like the interaction is with the anatomy, and how it behaves when one interacts with the anatomy.

HT's objectives are to provide both an alternative to current medical training methods and to provide a level of education not possible with traditional techniques. Only those virtual environments that offer sufficient realism constitute a commercially viable alternative to established practice on cadavers, animals and patients. Realism in the context of virtual environments for medical training relates to how the anatomical structures appear how life-like the interaction is with the anatomy, and how it behaves when one interacts with the anatomy. HT has advanced the state-or-the-art in surgical simulation by focusing on computationally intensive tasks such as physically-based modeling, collision detection, blood flow simulation, and tactile feedback. These techniques have been used in simulations including the endoscopic simulator. Standardized datasets of the human male and female serve as a common reference point for the study of anatomy and for incorporation into real-time visualizations and simulations.

Acknowledgments:

This work was supported in part by the Defense Advanced Research Projects Agency (DARPA), The Navy Medical Research and Development Command, The National Institutes of Health (NIH), and The National Institutes of Standards and Technology 's (NIST) Advanced Technology Program (ATP).