ABSTRACT
Promising new developments include the introduction of near-infrared-shifted fluorescent molecules that can be used for in vivo labeling of deep tissue functional and molecular processes. Due to versatility and wide availability of optical molecular agents, functional and molecular imaging studies can be done using extrinsic contrast from, e.g. reporter genes or targeted biomarkers that can be genetically expressed or accumulated in a cell- or tissue-specific manner. Despite its great promise, similarly to ultrasonography, optoacoustic imaging possesses several limitations related to imaging through acoustically mismatched areas, such as lungs, skull, and bones. The initial goal of optoacoustic imaging and tomography is retrieval of the absorbed optical energy density inside the object. The highly heterogeneous nature of biological tissues may further lead to the appearance of significant image artifacts and compromise imaging performance and quantification. The true multi-scale imaging capabilities of optoacoustics can be better appreciated when comparing its dynamic imaging performance with other neuroimaging modalities.
