Theranostics 2018; 8(22):6210-6232. doi:10.7150/thno.26610


PET-MR and SPECT-MR multimodality probes: Development and challenges

Chang-Tong Yang1,5,6✉, Krishna K. Ghosh1, Parasuraman Padmanabhan1, Oliver Langer3,4, Jiang Liu5, David Ng Chee Eng6,7, Christer Halldin1,2, Balázs Gulyás1,2

1. Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 59 Nanyang Drive, Singapore 636921.
2. Karolinska Institutet, Department of Clinical Neuroscience, S-171 76, Stockholm, Sweden.
3. Department of Clinical Pharmacology and Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, A-1090, Vienna, Austria.
4. Center for Health and Bioresources, Biomedical Systems, AIT Austrian Institute of Technology GmbH, Seibersdorf, Austria.
5. Cixi Institute of Biomedical Engineering, Ningbo Institute of Industrial Technology and Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, P.R. China, 315201.
6. Department of Nuclear Medicine and Molecular Imaging, Radiological Sciences Division, Singapore General Hospital, Outram Road, Singapore 169608.
7. Duke-NUS Medical School, 8 College Road, Singapore 169857.


Positron emission tomography (PET)-magnetic resonance (MR) or single photon emission computed tomography (SPECT)-MR hybrid imaging is being used in daily clinical practice. Due to its advantages over stand-alone PET, SPECT or MR imaging, in many areas such as oncology, the demand for hybrid imaging techniques is increasing dramatically. The use of multimodal imaging probes or biomarkers in a single molecule or particle to characterize the imaging subjects such as disease tissues certainly provides us with more accurate diagnosis and promotes therapeutic accuracy. A limited number of multimodal imaging probes are being used in preclinical and potential clinical investigations. The further development of multimodal PET-MR and SPECT-MR imaging probes includes several key elements: novel synthetic strategies, high sensitivity for accurate quantification and high anatomic resolution, favourable pharmacokinetic profile and target-specific binding of a new probe. This review thoroughly summarizes all recently available and noteworthy PET-MR and SPECT-MR multimodal imaging probes including small molecule bimodal probes, nano-sized bimodal probes, small molecular trimodal probes and nano-sized trimodal probes. To the best of our knowledge, this is the first comprehensive overview of all PET-MR and SPECT-MR multimodal probes. Since the development of multimodal PET-MR and SPECT-MR imaging probes is an emerging research field, a selection of 139 papers were recognized following the literature review. The challenges for designing multimodal probes have also been addressed in order to offer some future research directions for this novel interdisciplinary research field.

Keywords: bimodality imaging probe, PET-MR, SPECT-MR, contrast agent, radioligand

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How to cite this article:
Yang CT, Ghosh KK, Padmanabhan P, Langer O, Liu J, Eng DNC, Halldin C, Gulyás B. PET-MR and SPECT-MR multimodality probes: Development and challenges. Theranostics 2018; 8(22):6210-6232. doi:10.7150/thno.26610. Available from