Three-dimensional (3-D) rendering of medical imaging data allows clinical information to be accessed and manipulated in real time, which lets users analyze, display, and diagnose anatomical structures. To perform such volume-based rendering, sampled data must be interpolated, surface normals estimated, and color and shading factors assigned.
Because real-time rendering of these data is computationally intensive, it requires special custom hardware. Recognizing this need, the Mitsubishi Electric Corp. Semiconductor Group (Sunnyvale, CA) and Real Time Visualization Group (RTViz; Concord, MA) introduced in 1999 the VolumePro 500, a PCI-based add-in board (seeVision Systems Design, July 1999, p. 9). Capable of processing 500 million Phong-lit, trilinearly interpolated samples per second, the board is capable of volume rendering a 2563 data set at 30 frames/s.
Three months ago, Mitsubishi sold its RTViz Group to TeraRecon (San Mateo, CA), an OEM supplier of medical image processors. To support the VolumePro board in a number of medical applications, TeraRecon is working with several application software developers, toolkit developers, and system integrators (see table). These software packages provide a number of different functions, including automatic and interactive segmentation tools, volume visualization, and three-dimensional image measurement functions.
The company is also pursuing manufacturers of PC-based medical imaging hardware. For example, TomTec Imaging Systems GmbH (Munich, Germany) has recently incorporated the VolumePro board into its line of 4D Cardio-View three-dimensional ultrasound systems. Designed to display and evaluate 3-D ultrasound images, the systems are targeted toward transesophageal echocardiography, transthoracic echocardiography, and cardiac data acquisition. Available for stand-alone Windows NT workstations or as an add-on option for TomTec's 3-D workstations, 4D Cardi-View is supplied with the company's Easy-Scan software that combines cardiology acquisition software for computerized 3-D image processing.
