A diffuse reflectance spectroscopy system to study biological tissues

Diffuse reflectance spectroscopy (DRS) is a technique that allows the study of the structural and biochemical condition of tissues in a noninvasive-nonionizing way. DRS has been widely used in biomedical applications, mainly as an alternative to biopsy. Generally, the technique consists in the irradiation of a specific zone of a tissue with a reference spectrum. Then, the reemitted by the tissue light is detected. The changes suffered by the backscattered spectrum (after light-tissue interaction) with respect to the incident one carry information about the tissue properties. This work presents a novel system designed and developed to use DRS in biomedical applications. The system uses a LED as a light source and a specially designed optical fiber probe as a mean to deliver the light to the tissue surface, and to collect the reemitted photons from the studied sample. This probe was designed to accomplish two different tasks: to increase the sensitivity of the diagnosis; and to study the radial dependence of the backscattered light. The measuring probe was built in a way that allows taking readings when the exerted pressure on the tissue reaches certain predetermined values.