Using the Visible Human Male for Modeling and Displaying Trauma 2005-01-2719
The National Library of Medicine’s Visible Human Project began with a contract to cryosection and photograph one male and one female cadaver. The University of Colorado’s Center for Human Simulation (CHS) performed the research and supplied the raw images, which have been freely distributed since. However, the steps required to create models suitable for studying and displaying trauma dwarf the creation of the original images.
Over the past ten years, the CHS has spent approximately 20 people years segmenting and classifying the data. This process creates a number for each volume element (voxel) that identifies the structure to which it belongs and becomes the major driver of the database of associated properties. Creating polygons from this data differs from the creation of polygons from fuzzy data such as Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) and has led us to develop our own polygon creation methods as well.
The focus of the CHS is the creation of virtual anatomy, utilized in simulators to teach surgical and allied skills. In order to create anatomic models in clinically relevant states, including pathologies, we have developed offline finite element modeling techniques that predict the deformations of soft tissues in response to movements of surrounding bones. The pre-calculated data is then displayed in real-time allowing the student to, for example, flex a joint and observe the movement of the relevant tissues.
This paper reports on our most recent effort to create a fractured femur simulator that allows authors to pick an object and send it at the thigh of the Visible Human Male (VHM). The resulting stresses and strains are used to predict damage to the femur and surrounding tissues as well as to create models for display in the virtual environment. The method is extensible to virtually any object used for collision with any and all parts of the VHM.