When computed tomography (CT) was developed and introduced by Hounsfield (1973), a new era of clinical diagnostic potential began. At the same time CT created new difficulties, in that the physicians who had to deal with the CT images were not acquainted with their interpre tation. Therefore, it became necessary to compare CT scans with ana tomical sections, which gave additional information by virtue of their higher resolution, the different colors and consistencies of the struc tures, and the possibility to trace these structures across several sections. Several atlases comparing CT scans...