RT Journal Article SR Electronic T1 PET/MRI, Part 2: Technologic Principles JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP 217 OP 225 DO 10.2967/jnmt.120.261862 VO 49 IS 3 A1 Geoffrey M. Currie A1 Peter Kamvosoulis A1 Stewart Bushong YR 2021 UL http://tech.snmjournals.org/content/49/3/217.abstract AB The challenges of hybridizing PET and MRI as a simultaneous modality have been largely overcome in recent times. PET hybridized with MRI has seen the emergence of PET/MRI systems in the clinical setting, and with it comes a responsibility to adapt appropriate facility design, safety practices, protocols and procedures, and clinical opportunity. This article provides an insight into the considerations and challenges associated with PET/MR technology. Given that the nature of PET is well established among the readership of this journal, the article provides an introduction to the foundations of MRI instrumentation and emphasis on specific technologic aspects of PET/MR systems. This article is the second in a 4-part integrated series sponsored by the PET/MR and Publication Committees of the Society of Nuclear Medicine and Molecular Imaging–Technologist Section, building on the previous article (part 1), which was on establishing a facility. In subsequent parts, PET/MRI will be explored on the basis of protocols and procedures (part 3) and applications and clinical cases (part 4).