Method of processing a broadband elastic scattering spectrum obtained from tissue

A method of processing a broadband optical elastic scattering spectrum obtained from tissue comprises the steps of: obtaining, in a plurality of fitting ranges of wavelength, fitting parameters giving a best fit to the spectrum in the respective fitting ranges; and recording the fitting parameters as a parameter set representing the spectrum; wherein in at least one fitting range the fit is to the absorption of at least one predetermined component, for example, haemoglobin, and in the reminder of the fitting ranges the fit is to a smooth function. The fitting parameters may be used for classifying the tissue, preferably using hierarchical cluster analysis. An apparatus for obtaining elastic scattering spectra from tissue and adapted to process the spectra using the above method is also claimed.