Fig 1. Step-by-step illustration of the rigid registration algorithm.
[18F]FMISO and [18F]FDG/ PET/CT datasets in two separate coordinate systems (yellow and blue) are rigidly registered (CT1-CT2 registration) and merged into one (green). Registration between the green and the red (mpMRI) coordinate system is performed by a rigid transformation of CT2 to fit T1w MRI. The calculated transformation is applied to PET1 and PET2 to create the PET/MRI dataset (purple).