Abstract: A non-invasive method for detecting deep venous thrombosis in a human body wherein changes are effected in the amount of deoxyhemoglobin in the body limb by trapping blood in the venous system for a determinate time period and then releasing the trapped blood in the venous system. During the period that the changes in the amount of deoxyhemoglobin are effected, first and second light sources emit light of two selected wavelengths which penetrate into the deep venous system of the body limb so that the reflectance contributions can be used to measure changes in the flow and amount of deoxyhemoglobin and to thereby detect the presence or absence of deep venous thrombosis.

Abstract: A method and apparatus for measuring oxidative metabolism in an internal organ or tissue of interest wherein a percutaneous intravascular approach is utilized to bring a light-transmitting and receiving scope into contact with the site to be assessed. The tip of the scope is adapted so that the light-transmitting optical fiber(s) and light-receiving optical fiber(s) are in divergent relationship so as to increase the photon pathlength through the tissue of interest to provide optical information from a substantial volume of tissue relative thereto.

Abstract: A method and apparatus for measuring oxidative metabolism in an internal organ or tissue of interest wherein a percutaneous intravascular approach is utilized to bring a light-transmitting and receiving scope into contact with the site to be assessed. The tip of the scope is adapted so that the light-transmitting optical fiber(s) and light-receiving optical fiber(s) are in divergent relationship so as to increase the photon pathlength through the tissue of interest to provide optical information from a substantial volume of tissue relative thereto.

Abstract: The invention comprises a noninvasive method and device that allows detection of tissue infiltration during the administration of fluids. In the invention, the tissue surrounding the site of intravenous injection is exposed to a plurality of wavelengths of electromagnetic radiation when no infiltration is occurring to determine a baseline reading. Changes in the relative levels of detected radiation at each wavelength as compared to the baseline reading indicate tissue infiltration.