Multimodal fibre-probe spectroscopy for tissue diagnostics
Multimodal fibre-based spectroscopy offers the possibility of non-invasively and quickly detect spectroscopic information of the tissue under examination. This technique combines several laser sources emitting in the UV, visible, and NIR spectral range with the aim of performing a multimodal measurement of the optical-spectroscopic features of the sample. By choosing the proper excitation wavelength, fluorescence spectroscopy is able to target at the emission of tissue intrinsic fluorophores, such as NADH, FAD and others. Reflectance spectroscopy can provide information on tissue scattering and absorption properties, as well as on the size of scatterers. In addition, by analysing reflectance data, it is possible extracting important information for tumour diagnostics, such as blood oxygenation level and cell nuclear size. Finally, the use of Raman spectroscopy permits to create a chemical-molecular fingerprint of the examined tissue because it depends on the vibrational molecular energy structure. Combined fluorescence, reflectance and Raman spectroscopy offers the possibility of a multi-parametric analysis of a tissue, as well as of classifying the physiological condition on the basis of the spectroscopy parameters measured. The multi-parametric analysis gives the possibility of assigning a spectroscopic-functional fingerprint to the tissue, which could be crucial for assessing physiological conditions. In this experiment, all the mentioned spectroscopic techniques will be implemented in an optical fibre bundle probe and tested through the examination of freshly excised tissue biopsies. Final aim is to transfer the technology to clinical practice.
Sketch of the fiber-optic sensor for multimodal fiber-probe spectroscopy.