Physics of Hybrid Imaging

  • Girolamo Garreffa
  • Gisela Hagberg
  • Luca Indovina


The main purpose of multimodality imaging is to provide an advanced diagnostic tool by combining measurements of anatomy and physiology obtained with different techniques – in particular PET-TC and PET/MRI. Multimodality imaging can refer to two main fronts each characterized by the space-time context of data acquisition. Either such morphofunctional, multimodal images are generated by fusing images acquired with each technique separately and at different times or they may arise from truly contextual or simultaneous acquisitions. In this latter case, we are speaking of a hybrid system. There are many potential advantages of hybrid imaging, since ideally both anatomical and functional information can be obtained at the same time without any time delays between modalities and without any need for coregistration of the image information. Beyond this attractive prospect, there are some pivotal synergistic effects that come with the integration of multiple modalities, mainly relating to correcting PET data to yield truly quantitative information while maximizing the signal-to-noise ratio. In this chapter we shall briefly recall some basic physics concepts of each single and combined imaging technique: PET, CT, and MRI.


Positron Emission Tomography Scanner Magnetic Resonance Signal Coincidence Event Annihilation Photon Positron Emission Tomography 
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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Girolamo Garreffa
    • 1
  • Gisela Hagberg
    • 2
  • Luca Indovina
    • 3
  1. 1.Head of Applied Physics SectionEuro-Mediterranean Institute of Science and Technology I.E.ME.S.T.PalermoItaly
  2. 2.Scheffler Group, MPI for Biological CyberneticsUniversity Hospital TübingenTubingenGermany
  3. 3.Health Physics UnitFondazione Policlinico Universitario A. GemelliRomeItaly

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