| dc.description.abstract | A procedure on how to extract intrinsic fluorescence, i.e. fluorescence only due to fluophores, out of biological samples by imaging is given. Measurement of fluorescence of biological tissue will generally be distorted by the presence of absorbers and scatterers, and the measurement of fluorescence for medical diagnosis is limited. A method of recovering intrinsic fluorescence would, however, enable fluorescence measurement as a diagnostical tool. An expression based on a so-called one-dimentional path-length factor \mathrm{X_{1D}}
, which characterize the effective path length of excitation light penetrated into the biological sample and the escape of fluorescence light from the sample, is proposed and testet in this thesis. The method assumes knowledge of the optical properties the material is assumed, while all other data is acquired by imaging. Software applications for image acquisition and data analysis has been developed, and a user manual of these software applications is provided along with a complete description of procedure on how to recover the intrinsic fluorescence.
The method was tested on homegenous liquid tissue phantoms with different concentrations of fluorophores and absorbers. To complement the measurements, spectrometer was done, but these measurements were not a part of the proposed procedure. The correspondance between experimental results and theory was weak. The obtained values of intrinsic fluorescence were too high for the phantoms with high absorption coefficients compared to the obtained values of intrinsic fluorescence for the phantoms with less absorers. Poor estimation of the optical properties of the materials is suggested as the main reason for unexpected experimental results. | |
