| For decades, researchers have contributed with new ways of applying physics' principles to medicine. Moreover, researchers were involved in developing new, non-invasive instrumentation for medical applications. Recently, application of optical techniques in biology and medicine became an important field. Researchers found a non-invasive approach of using visible and near-infrared light as a probe for tissue investigation. Optical methods can contribute to medicine by offering the possibility of rapid, low-resolution, functional images and real-time devices.; Near-infrared spectroscopy (NIRS) is a useful technique for the investigation of biological tissues because of the relatively low absorption of water and high absorption of oxy- and deoxy-hemoglobin in the near-infrared region of 750–900 nm. Due to these properties, the near-infrared light can penetrate biological tissues in the range of 0.5–2 cm, offering investigation possibility of deep tissues and differentiate among healthy and diseased tissues.; This work represents the initial steps towards understanding and improving of the promising near-infrared frequency-domain technique. This instrument has a very important advantage: it can be used non-invasively to investigate many parts of the human body, including the brain.; My research consists primarily of in vivo measurements of optical parameters such as absorption and reduced scattering coefficients and consequently, blood parameters such as oxy, deoxy, and total hemoglobin concentrations, tissue oxygen saturation, blood flow and oxygen consumption of skeletal muscle of healthy and diseased subjects.; This research gives a solid background towards a ready-to-use instrument that can continuously, in real-time, measure blood parameters and especially blood oxygenation. This is a very important information in emergency medicine, for persons under intensive care, or undergoing surgery, organ transplant or other interventions. |
