2017 Imaging for Physicists Coursebook

Making a PET-CT for radiotherapy

• Registration of bony anatomy of a diagnostic PET-CT to planning CT is accurate • baseline shift of tumor (shift relative to bony anatomy) frequently occurs • gated (4D) PET-CT scan – SUV values higher than on blurred 3D scan – More precise imaging of tumor • Attenuation correction on a single phase (mid-ventilation) of a 4D CT scan provides reliable SUV values