To solve such a problem that three-dimensional images photographed by different photographing apparatuses (photographing methods or modalities) are difficult to be displayed separately in a common display orientation.

A coordinate system 1 based on landmarks on a bone and a coordinate system 2 based on landmarks on skin are set in a CT image. A transformation coefficient (a correction amount) Tc between the coordinate systems 1, 2 is calculated and stored. When image data obtained by the different imaging method is displayed and the image data includes a bone display layer, a coordinate system being equal to the coordinate system 1 of the CT image is set. When the image displays a skin display layer, a coordinate system being equal to the coordinate system 2 of the CT image is set. The set coordinate system is corrected with the use of the transformation coefficient Tc, so that the coordinate system 1 can be corrected into the coordinate system 2 or the coordinate system 2 can be corrected into the coordinate system 1. Consequently, the image is displayed based on the common coordinate system between the different image data.

COPYRIGHT: (C)2007,JPO&INPIT