The Use of Dual Modality PET/MRI in Population Studies: Considerations on Exposures, Economics, Strengths, and Limitations

In 2011, the US Food and Drug Administration (FDA) approved the clinical use of hybrid PET/MR imaging scan technology, permitting a new era of possibilities and benefits to public health and economic sectors surrounding clinical and research applications. The prior widespread application of PET/CT scans exposed patients and research participants alike to higher levels of radiation and rendered lower-contrast soft tissue images than MRI. In this chapter we discuss how the introduction of hybrid PET/MR scanning mitigates excessive radiation, which is of immense importance to pediatric and geriatric populations, and how rendering higher-contrast structural images can lead to better clinical and research interpretations. In addition, before hybrid PET/MR, scans requiring the use of both PET and MRI required separate scheduling times for conducting two independent imaging runs. This often led to increased individual patient burden and potentially higher costs along with issues regarding inter-scan image alignment. We highlight how simultaneous imaging of both these scanning modalities potentially reduces such burden and cost and improves the interpretation of scans. Furthermore, a focus of this chapter also lies within discussing the benefits of new research paradigms made possible using this new technology, along with certain inherent pitfalls, such as sampling bias during research participant recruitment. Finally, we explore the ever-evolving landscape as hybrid PET/MR technology becomes more widespread and implemented in research and clinical centers around the world, and how ongoing and future applications continue to impact public health and economic considerations.