Tissue diagnostics using laser-induced fluorescence techniques

Abstract

The fluorescence emission from tissue subject to UV light excitation can be utilized for diagnostic purposes. The discrimination between tumors and normal tissue is of particular interest. The natural tissue fluorescence can be used but improved results are obtained using the agent hematoporphyrin derivative that is selectively retained in tumors. We have used laser-induced fluorescence for point measurements1 as well as for multicolor imaging2 of different kinds of rat tissue. For optimized characterization it is important to utilize the full spectral information and to form dimensionless contrast functions of measured spectral intensities. The importance of selecting the proper excitation wavelength is emphasized. The development of clinical instrumentation for point measurements and imaging is discussed.