An off-line image processing system for digital display in computed tomography

Early clinical application of an off-line image processing and analysis system for digital display in conjunction with computed tomography is described. The system consists of three operational subsystems: (a) a flexible disk for digital storage of absorption values in each of eight or more tomographic planes; (b) a high-speed interactive video system which displays the tomographic plane in correct geometry with the absorption values, which serve as the pictorial elements; and (c) a paper hard copy of the absorption values in a simulated gray-tone image of the tomographic plane in which the numerical values are the pictorial elements. Both the video and paper displays provide explicit numerical values of x-ray attenuation for each location on the tomographic plane in an image which combines analog and digital qualities.