The present paper describes an attempt to display 3-D shaded images, which have been derived from a series of RI emission computed tomographic images (ECT) obtained by using a rotating gamma camera or a 7 pinholes collimator.
The creating procedure of the 3-D shaded images is as follows : The contours of the tomographic images are first determined. The 3-D geometric model of the organ of interest, which is approximated by many triangular patches, is summed up to be constructed in a computer. This model is projected on a screen and its hidden surfaces are eliminated by using a priority algorithm. Then the image is shaded to show up the surfaces of the organ vividly.
The system can be implemented in a standard gamma camera data processing system in order to help a physician to recognize the spatial relationship among several tomographic images.
