The Visible Ear Simulator

Background: Existing virtual simulators for middle ear surgery are based on 3-dimensional (3D) models from computed tomographic or magnetic resonance imaging data in which image quality is limited by the lack of detail (maximum, ∼50 voxels/mm3), natural color, and texture of the source material. Virtual training often requires the purchase of a program, a customized computer, and expensive peripherals dedicated exclusively to this purpose. Materials and Methods: The Visible Ear freeware library of digital images from a fresh-frozen human temporal bone was segmented, and real-time volume rendered as a 3D model of high-fidelity, true color, and great anatomic detail and realism of the surgically relevant structures. A haptic drilling model was developed for surgical interaction with the 3D model. Results: Realistic visualization in high-fidelity (∼125 voxels/mm3) and true color, 2D, or optional anaglyph stereoscopic 3D was achieved on a standard Core 2 Duo personal computer with a GeForce 8, 800 GTX graphics card, and surgical interaction was provided through a relatively inexpensive (∼2, 500) Phantom Omni haptic 3D pointing device. Conclusion: This prototype is published for download (∼120 MB) as freeware at http: //www. alexandra. dk/ves/index. htm. With increasing personal computer performance, future versions may include enhanced resolution (up to 8, 000 voxels/mm3) and realistic interaction with deformable soft tissue components such as skin, tympanic membrane, dura, and cholesteatomas-features some of which are not possible with computed tomographic-/magnetic resonance imaging-based systems.