Spettroscopia ottica diffusa risolta nel tempo del tessuto adiposo sottocutaneo dell'addome

In this work it has been investigated the possibility to study the abdominal subcutaneous adipose tissue through time-resolved near-infrared spectroscopy. As widely known in the field of diffuse optics, human tissues are highly diffusive media in the spectral range from the red to the near-infrared wavelengths (600-1100 nm, also known as therapeutic window). This allows one to apply this technique under the hypothesis of diffusion approximation to radiative transport equation: in diffusive media, where scattering dominates with respect to absorption, propagation of light can be studied using a particle definition of radiation, seen as a set of photons travelling through the medium. Measurements can be performed by sending light in the medium and collecting the emitted signal which carries information about the optical properties of medium photons propagated through. The scientific interest for abdominal subcutaneous adipose tissue is strictly related to various types of disease stemming from obesity. In this scenario, time-resolved near-infrared spectroscopy could play a key role as a powerful diagnostic technique to investigate abdomen lipid layer. This is possible thanks to the intrinsic non-invasive nature of radiation in the considered spectral range and, in my case, also thanks to an innovative portable compact system to perform such type of measurements. In order to properly understand and characterize optical properties of examined tissues, one must keep in mind the peculiar layered structured of abdomen. Indeed, through my measurements and analysis I showed that the implemented methodology is capable of investigating this medium and provides information about the anatomy of abdomen, demonstrating that my study paves the way to further research in this field.