TABLE 1

Comparison of Molecular Imaging Modalities

ModalitySignalClinicalPreclinical (rodent)Sensitivity*QuantificationAcquisition time (s)
PET11C, 18F, 64Cu, 68GaYesYes1Very good10s−100s
SPECT99mTc, 123I, 111In, 177LuYesYes10−1−10−2Good100s−1,000s
FluorescenceFluorescent proteins, fluorochromes, quantum dotsPotentialYes10−2−1†Poor to fair†1–10
BLILuciferaseNoYes1–102†Poor to fair†1–10
MRIGadolinium, SPIO, USPIO, 19FPotentialYes10−5Fair100s−1,000s
MRSEndogenous compounds, hyperpolarized 13CYesYes<10−5Fair100s−1,000s
UltrasoundMicrobubblesPotentialYes‡Poor<1

  • ↵* Relative to PET.

  • ↵† Depth-dependent.

  • ↵‡ Not well characterized.