Abstract: The data derived from a computerized axial tomographic apparatus in respect of a number of slices through a body are processed to produce a representation of the variation of absorption of X-rays over each slice. The representations are operated upon individually to identify areas which are of reduced interest and/or which are obscuring regions of especial interest. This having been done, the representations for all the slices are correlated to produce a pseudo three-dimensional display of part of the body with the identified areas being displayed with reduced or zero intensity as compared with other areas. Alternatively, the identified and other areas can be represented in different colors.