RT Journal Article SR Electronic T1 PET/MR Part 4: Clinical Applications of PET/MRI JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP jnmt.121.263288 DO 10.2967/jnmt.121.263288 A1 Geoffrey M Currie A1 Jose L Leon A1 Elad Nevo A1 Peter V Kamvosoulis YR 2021 UL http://tech.snmjournals.org/content/early/2021/12/06/jnmt.121.263288.abstract AB Position emission tomography (PET) and magnetic resonance imaging (MRI) as a hybrid modality provides novel imaging opportunities. While there are a very broad array of pathologies that could benefit from PET/MRI, there is only a narrow range of applications where benefit over standard care justifies the higher resource utilization and, in particular, offers a net positive trade-off over PET/CT. This benefit is generally associated with the omission of CT and the associated radiation dose from the patient workup. This manuscript provides a summary of the generally accepted clinical applications of PET/MRI in both adult and pediatric populations. While there are a number of potential applications and certainly exciting research that may expand applications in the future, the purpose of this paper was to focus on current, mainstream applications. This is the final manuscript in a four-part integrated series sponsored by the SNMMI-TS PET/MR Task Force in conjunction with the SNMMI-TS Publication Committee.