Optimized protocol for hybrid PET-MR imaging in prostate and breast cancers

Objectives A hybrid device combining a PET and an MRI scanner for whole body scanning was evaluated for oncological application in breast prostate cancer staging and follow-up. Optimized imaging protocols allowing diagnostic quality studies of both modalities to be acquired in limited for routine clinical applications were implemented.

Methods a new whole-body scanner combining a 3T MR and a time-of-flight PET scanner sharing a single bed allowing sequential acquisition of co-registered MR and PET images was tested. This device consist of the two separate scanners linked through a single patient table allowing sequential imaging of the patient moving from one device to another. Eighteen patients were studies for prostate cancer and 12 patients for breast cancer. Standard imaging protocols of both modalities were combined to allow optimized acquisition sequences for loco-regional assessment of tumor extension as well as whole body staging. Images were interpreted by multidisciplinary teams of radiologists and nuclear physicians in the same way it is routinely done for hybrid PET-CT studies.

Results optimized imaging protocols allowing full diagnostic quality of both modalities while reducing the total time of the study were developed and provided adequate diagnostic quality of both modalities. Clinical results from this hybrid imaging technique applied prostate and breast investigations will be presented and the results and workflow optimization will be discussed.

Conclusions this paper presents optimized imaging protocols that were developed for hybrid PET-MR imaging device in specific oncological studies. Simplification and optimization of imaging protocols will be discussed and evaluated. Advantages and limitations of this new technique will be compared to existing PET-CT technique