Fluorescent protein tomography scanner for small animal imaging

Abstract—Microscopy of fluorescent proteins has enabled un-precedented insights into visualizing gene expression in living sys-tems. Imaging deeper into animals, however, has been limited due to the lack of accurate imaging methods for the visible. We present a novel system designed to perform tomographic imaging of fluo-rescent proteins through whole animals. The tomographic method employed a multiangle, multiprojection illumination scheme, while detection was achieved using a highly sensitive charge-coupled de-vice camera with appropriate filters. Light propagation was mod-eled using a modified solution to the diffusion equation to account for the high absorption and high scattering of tissue at the visible wavelengths. We show that the technique can quantitatively detect fluorescence with sub millimeter spatial resolution both in phan-toms and in tissues. We conclude that the method could be applied in tomographic imaging of fluorescent proteins for in vivo targeting of different diseases and abnormalities. Index Terms—Diffusion theory, fluorescence tomography, vis-ible light, whole-body imaging. I