stored with the axial slice image data in second section 40 of data storage device or medium 30 preferably these sagittal and coronal slice images are stored in exactly the same data format as the 2 d axial slice images whereby they may be easily accessed by computer 50 and displayed on display 60 in the same manner as has been previously discussed in connection with axial 2 d slice images as a result axial sagittal and coronal 2 d slice images can be displayed on display 60 either individually or simultaneously in separate windows in the manner shown in fig1 furthermore when generating a composite image of the sort shown in fig1 i e an image generated from both the 3 d computer model contained in first section 35 of data storage device or medium 30 and a 2 d slice image contained in second section 40 of data storage device or medium 30 the composite image can be created using axial sagittal or coronal 2 d slice images as preferred it is also to be appreciated that the system of the present invention is also configured so as to generate and utilize oblique 2 d slice image data in place of the axial sagittal and coronal slice image data described above more particularly computer 50 is programmed so that a physician can use input devices 55 to specify the location of the oblique 2 d slice image desired and then computer 50 generates that 2 d slice image from the volumetric.