Color 3-D Imaging of Normal and Pathologic Intracranial Structures

The overall feasibility of 3-D color imaging is determined, taking into account display method, display options, and image processing system. The method is based on the display of 3-D colored ranges of data values and allows very complex convoluted structures with disjoint parts to be imaged. This approach results in a very fast, interactive method for interpreting the position, size, and shape of 3-D structures. Display options are needed to clarify the perception of the three-dimensional relationships; a single presentation mode is not sufficient. Seven options are used: multiple structures, point of view, projection angle, cutout, transparency, contours, and stereo. The options are selected by interacting visually with the image of the 3-D structures on a high-resolution color monitor 1024×1024. The image processing system consists of a host computer IBM 370/168 and an image processing workstation IBM 7350. The host performs data file management, selection of subimages, initial data smoothing, and 3-D data rotation. The workstation provides interactive 3-D imaging with oblique projection, data cutout, transparency, smoothing, and color selection. Since all of the scan data are resident in the 7350 storage buffers, 3-D images can be formed in 10 to 20 seconds. These techniques are illustrated using computer tomography (CT) scans from a group of patients with various structural abnormalities of the brain. Examples of the enhanced diagnostic capability of CT with 3-D imaging as well as its application in the surgical approach to tumors of the central nervous system (CNS) are presented.