Contrast agent for combined modality imaging and methods and systems thereof

In accordance with embodiments of the present technique, a combined modality imaging system (10) includes a first imaging device of a first modality (12) and a second imaging device of a second modality (14) that is different from the first modality (12). The first and the second imaging devices are both adapted to interact with a contrast agent (18) adapted to be received in a subject (16). The contrast agent (18) includes a deformable particle that has a geometry that varies in response to an emission from the first imaging device. The deformable particle also includes a fluorescent component (70) adapted to emit electromagnetic radiation (28) that is detectable by the second imaging device and a quenching component (72) separated from the fluorescent component (70) at a distance based on the geometry and that which is adapted to absorb a portion of the electromagnetic radiation (28) from the fluorescent component (70).