Sample output of deformable image registration. The columns from left to right are the axial, sagittal, and coronal planes, respectively. The white arrows indicate the left lung lesion and the right lung latent lesion. (a) Moving images (previous images) in the axial plane. The lengths of the long and short diameters of the left lung lesion are 33 and 20 mm, respectively. (b) Fixed images (current images, interval of 4 months 6 days). In the axial plane, the long and short diameters of the left lung lesion are 40 and 18.5 mm, respectively. (c) Warped moving images. The long and short diameters of the left lung lesion are 33 and 20 mm, respectively. (d) Overlapping of moving and fixed images (showed misregistration). The position of the lung surface shows a clear difference between moving and fixed volumes. (e) Overlapping of the warped moving and fixed images (well-matched). Red indicates the warped moving image and green indicates the fixed image. (f) Log-Jacobian image of the deformation field.