Deformation and summation of breath-hold PET images

A breath-hold (BH) acquisition method is easy of operation and recently studied actively. In the method, a patient is asked to hold his/her breath for 10 to 30 s as the image acquisition is performed. This is repeated several times and the obtained images are summed. In practice, however, a patient cannot necessarily hold his/her breath at the same timing of breathing. In such a case, the summed images still has a blur. In this paper, we propose to apply our image registration method developed before for respiratory-gated images to BH images. The BH images are nonlinearly motion-corrected so as to match a reference BH image and summed. Through the experiment with ten patient BH image data, we confirmed that the proposed method is effective in obtaining a non-blurred image.