Abstract
Interval changes in medical images (such as formation of new lesions and changes in existing abnormalities) can be enhanced by removing most of the normal structures. For this purpose, the temporal subtraction image is obtained by subtraction of previous image from the current image. If the image registration is incorrect, not only the interval changes but also the normal structures appear as artifacts on the temporal subtraction image. In this study, we developed a temporal subtraction algorithm for MR images of brain and applied it to five clinical cases. Preliminary results indicated that the algorithm considerably enhanced the interval changes in the subtraction images and substantially reduced the number of misregistered artifacts. Therefore, it was apparent that artifacts in the temporal subtraction images were largely reduced by incorporating the image warping technique into image subtraction algorithm.
