Molecular imaging | In vivo imaging of the spatiotemporal distribution of molecular or cellular processes |
Cellular imaging | In vivo imaging of the spatiotemporal distribution of cellular processes |
Contrast agent, label | Chemical functional group that allows visualization by an appropriate imaging technique: For example, Gd chelates or iron oxides are MR imaging contrast agents, 18F atoms are PET contrast agents, and  fluorophores are optical contrast agents |
Nanoparticle | Molecules in the 10- to 1000-nm range that serve as an imaging platform; examples include SPIO particles, liposomes, dendrimers, and quantum dots |
Reporter probe, reporter molecule | A molecule or nanoparticle that is used to image particular biological processes; the molecule or nanoparticle is a composite of a contrast agent and targeting moiety |
Reporter cell | A cell that contains a contrast agent |
Reporter gene | A gene that encodes for a protein that (directly or indirectly) is easy to assay; reporter genes are linked to genes of interest to study expression levels |