Development of IDL-based software for multimodal image registration

Image registration with anatomical modalities such as CT and MRI, facilitates the anatomical localization in the interpretation of nuclear medicine images, which are relatively lacking in anatomical information. User-friendly program for image registration and fusion of registered images was developed. In consideration of easy transplantation to various operating systems (OS), the program was developed using IDL language. For the registration without operator's interaction, several automatic algorithms were implemented, which include principal axes matching and maximization of mutual information methods. User interface was designed to support the manual registration using point landmarks and the correction for unwanted mis-registration. Fused images were composed by overlaying one image with the other one transparently, in which the opacity of overlaid image was interactively controlled. OS and platform independent program for image registration was developed based on IDL language. It will be useful for the clinical application of image registration techniques