December 29, 2014 — Manufacturers have introduced hybrid imaging systems that combine positron emission tomography (PET) with magnetic resonance imaging (MRI). The purported benefit is improved detail in organ and soft-tissue images without the ionizing radiation inherent with systems that combine PET with computed tomography (CT), the gold-standard hybrid imaging modality.
Utilization is affected by the uncertain reimbursement environment for integrated PET/MRI scans. Some private, third-party payers (Aetna, Anthem, Humana) deny coverage for the hybrid imaging exams. Clinical trials comparing PET/MRI to PET/CT imaging have generally not demonstrated a substantial difference in diagnostic accuracy between PET/MRI and PET/CT, affecting anticipated utilization.
ECRI Institute’s expert panel thought that the possible development of new PET radiotracers targeting brain structures and soft tissue tumors might increase PET/MRI utilization for certain indications, especially if evidence demonstrates a benefit in diagnostic accuracy and if reimbursement becomes available.
Potential Health Impact
Most clinical trials of PET/MRI underway are comparing it with PET/CT. Heusch et al. (2014) found no significant differences in tumor detection between the two modalities. Quick et al. (2013) reported that PET/MRI detected more tumors than PET/CT. However, other trials (Chandarana et al. 2013, Gaertner et al. 2013, Wiesmuller et al. 2013) found that PET/MRI detected most tumors identified by PET/CT. Afshar-Oromieh et al. (2014) and Beiderwellen et al. (2013) concluded that PET/MRI may have better contrast and tumor conspicuity than PET/CT, but Gaertner et al. (2013) found better tumor conspicuity with PET/CT.
Potential Financial Impact
Hospitals face substantial costs to acquire integrated PET/MRI technology, including construction or renovation required to accommodate the combined system’s physical requirements and to install MRI-compatible (nonmagnetic) ancillary medical equipment needed during imaging procedures. As changes in healthcare coverage place a greater financial burden on healthcare consumers, some patients may forgo expensive procedures or diagnostic tests, thereby reducing demand for some technologies.
For more information: www.ecri.org
April 10, 2024 
![(A) PET images of [68Ga]Ga-DOTA-ZCAM241 uptake at baseline and 3, 7, and 12 days after injection as inflammatory arthritis developed in single representative individual mouse. Images are normalized to SUV of 0.5 for direct comparison between time points. (B) CD69 immunofluorescence Sytox (Thermo Fisher Scientific) staining of joints of representative animals during matching time points.](/sites/default/files/styles/feed_medium/public/PET%20Tracers.jpeg?itok=P5Di6MIe)
