Emerging clinical applications for PET/MR in the field of cardiovascular imaging

In the same way in which PET/CT has been shown to be a powerful multimodality imaging tool, there are compelling reasons for combining PET and MRI. Combined PET-MRI systems, i.e. the simultaneous acquisition of PET and MR images, combine the most sensitive and robust noninvasive clinical technology for molecular imaging (PET) with high-contrast, high-resolution and time-resolved MR imaging. The fusion of these two modalities into one acquisition system has represented a clear breakthrough in the imaging field, and the implementation of these imaging systems for clinical applications still remains a challenge. However, a certain number of pitfalls still remain and must be avoided. In this review, we will first discuss the technological advancements, which take advantage of simultaneous PET and MR acquisitions, such as improved attenuation and motion correction, but also the remaining issues, which must be considered when performing this combined imaging. Second, we will present the first clinical applications of PET-MRI emerging in the field of cardiac imaging. Lastly, we will review promising future clinical applications for PET-MRI in the vascular field.