TABLE 1.

Comparison of molecular imaging modalities

Modality	Signal	C	R	Sensitivity #	Quantification	Acq. Time (sec)
PET	11C, 18F, 64Cu, 68Ga	Y	Y	1	Very Good	10s–100s
SPECT	99mTc, 123I, 111In, 177Lu	Y	Y	10−1 - 10−2	Good	100s–1000s
Fluorescence	Fluorescent proteins, fluorochromes, quantum dots	P	Y	10−2 -1 *	Poor to Fair*	1–10
BLI	Luciferase	N	Y	1-102 *	Poor to Fair*	1–10
MRI	Gd, SPIO, USPIO, 19F	P	Y	10−5	Fair	100s–1000s
MRS	Endogenous compounds, hyperpolarized 13C	Y	Y	<10−5	Fair	100s–1000s
US	microbubbles	P	Y	**	Poor	<1

C=Clinical, R=Preclinical (rodent), P=Potential;

^#Relative to PET;

^*Depth dependent;

^**Not well characterized