| Popis: |
We present in this paper the effect of dehydration on the behavior of reflectance (R) and transmittance (T) on the arterial wall. The behavior of R and T at 633 nm as a function of tissue dehydration, measured on fresh arteries exposed to air, shows two domains of variation. For water loss up to a value of about 60% of the initial tissue weight, the tissue shrinks, but its reflectance and transmittance remain almost constant. In this region, the absorption and scattering coefficients, deduced from a diffusion model, increase with dehydration. For greater water loss, a significant increase of T and correspondent decrease of R are observed. This behavior is related to a tissue denaturation. This study shows that the dehydration is an important parameter in determining the correct dose of laser light that needs to be applied to obtain the desired effect, since it leads to variations of the tissue optical properties. |
