Chapter 12: “In Vivo” Molecular Imaging

Whole body optical imaging (OI) refers to in vivo bioluminescence and fluorescence imaging. This technology is one of the most rapidly emerging to non-invasively follow molecular and cellular processes in small laboratory animals. Optical imaging modalities are based on very sensitive devices capable of detecting and quantifying bioluminescent or fluorescent light that is transmitted through tissues from internal sources. This imaging of very weak visible light is rendered possible by the use of cooled charged coupled device (CCCD) cameras, peltier-cooled detectors, micro-plate channel intensifiers and liquid-nitrogen-cooled detectors aimed at enhancing the signal-to-noise ratio by decreasing the background or amplifying the signal. The role of molecular imaging in pre-clinical research is continuously evolving. Particularly in small animal models in biomedical research, optical imaging technologies are frequently used to visualize normal as well as aberrant cellular processes at a molecular-genetic or cellular level of function.

This chapter will focus on the application of whole body bioluminescence molecular imaging strategies -either alone or in combination with CT- in different fields (e.g. to study non-invasive and real-time imaging of gene expression, tumor progression and metastasis, and response to therapeutic intervention).