Hematoporphyrin mediated laser induced fluorescence in vivo imaging of tumor and organs structure in small animals

Recently we presented a prototype for fluorescence and radionuclide planar imaging system in small animals and its use in the analysis of solid surface tumors was assessed. The optical part is based on the detection of the red fluorescence radiation emitted by a hematoporphyrin (HP) compound injected systemically in the mice and accumulated in tumors, under green light illumination of the mouse body. Here we report on the improvement we made on the optical system, by using a high-sensitivity cooled CCD camera and optical magnification via a stereomicroscope. Our in vivo fluorescence measurements on tumor-bearing mice show that the use of the more sensitive, low noise, high resolution CCD camera not only allows for the detection of tumors and tissues where HP accumulates but also the investigation of their structure.