Fig. 1.

Use of deformable registration to register ¹⁸F-fluciclovine to the simulation computed tomographic (CT) scan. (a) Simulation CT scan at the level of a lymph node with positive uptake in positron emission tomography (PET)-CT, with an arrow marking the location. (b) Rigid registration of the CT component of the PET scan. Although the rigid registration matches the bone and muscles, it cannot model lymph node displacement between the scans. (c) Deformable registration. (d) Quality of the displacement field inspected to ensure smooth and anatomic plausible warping of standardized uptake value (SUV) activity. (e) PET mapped to the simulation CT dataset with rigid registration. (f) The same activity warped with deformable registration and iso-SUV levels.