Modified Median Root Prior reconstruction of PET/MR data acquired simultaneously with the 3TMR-BrainPET

In this paper, a Maximum a Posteriori Reconstruction algorithm using a Modified Median Root Prior is applied to data from the Siemens 3TMR-BrainPET scanner. This Prior was implemented in the PET REconstruction Software TOolkit (PRESTO) [1] which uses Highly Rotation-Symmetric Voxel Assemblies. The Modified Median Root Prior was developed to take advantage of the anatomical information coming from MR images. Simulated data was used to quantitatively assess the performance of the algorithm. Simultaneously acquired PET and MR data of a human patient was used to show the feasibility of this Prior. The results are compared to those of OSEM and of standard MRP and show a better Mean Squared Error.