The Visible Human digital datasets make it possible to develop computer-based anatomical training systems that use virtual anatomical models (virtual body structures-VBS). Medical schools are combining these virtual training systems and classical anatomy teaching methods that use labeled images and cadaver dissection. In this paper we present a customizable web-based three-dimensional anatomy training system, W3D-VBS. W3D-VBS uses National Library of Medicine's (NLM) Visible Human Male datasets to interactively locate, explore, select, extract, highlight, label, and visualize, realistic 2D (using axial, coronal, and sagittal views) and 3D virtual structures. A real-time self-guided virtual tour of the entire body is designed to provide detailed anatomical information about structures, substructures, and proximal structures. The system thus facilitates learning of visuospatial relationships at a level of detail that may not be possible by any other means. The use of volumetric structures allows for repeated real-time virtual dissections, from any angle, at the convenience of the user. Volumetric (3D) virtual dissections are performed by adding, removing, highlighting, and labeling individual structures (and/or entire anatomical systems). The resultant virtual explorations (consisting of anatomical 2D/3D illustrations and animations), with user selected highlighting colors and label positions, can be saved and used for generating lesson plans and evaluation systems. Tracking users' progress using the evaluation system helps customize the curriculum, making W3D-VBS a powerful learning tool. Our plan is to incorporate other Visible Human segmented datasets, especially datasets with higher resolutions, that make it possible to include finer anatomical structures such as nerves and small vessels.

Major efforts are being made to improve the teaching of human anatomy to foster cognition of visuospatial relationships. The Visible Human Project of the National Library of Medicine makes it possible to create virtual reality-based applications for teaching anatomy. Integration of traditional cadaver and illustration-based methods with Internet-based simulations brings us closer to this goal. Web-based three-dimensional Virtual Body Structures (W3D-VBS) is a next-generation immersive anatomical training system for teaching human anatomy over the Internet. It uses Visible Human data to dynamically explore, select, extract, visualize, manipulate, and stereoscopically palpate realistic virtual body structures with a haptic device. Tracking user's progress through evaluation tools helps customize lesson plans. A self-guided "virtual tour" of the whole body allows investigation of labeled virtual dissections repetitively, at any time and place a user requires it.

Haptics is a technology that creates a sense of touch in a multi-modal media. The availability of force feedback, haptics, requires the formation of haptic virtual objects. To aid in the creation of the haptic objects we have developed G 2 H, an interface between a commercial graphics and animation software package and the PHANToM haptic device. G 2 H is a modifier type plug-in that can be applied to any virtual object (created or imported). Application of the modifier converts objects into haptic objects. The objects can then be immediately touched with the haptic device in a number of configurable view-ports provided by the graphics software. G 2 H also allows the dynamic changing of haptic object properties, such as stiffness and static and dynamic friction A physical medical model is used to develop haptic virtual 3D objects on a PC/NT platform. A Commercially available digitizer and the graphics package are used to create virtual 3D objects. The application of G 2 H then converts these objects into haptic objects. The process makes it possible to develop complex and precise haptic virtual objects without writing code, thus allowing developers to work at a higher level than that offered by current labor-intensive techniques. For PC/NT based haptic virtual applications, this capability allows touchable objects, including volumetric objects, to be quickly created with a high degree of resolution.