In Vitro Validation of a New Tissue Oximeter Using Visible Light.

There is a clinical need to measure local tissue oxygen saturation (StO2), oxy-, deoxy- and total haemoglobin concentration ([O2Hb], [HHb], [tHb]) in human tissue. The aim was to validate an oximeter called OxyVLS applying visible light spectroscopy (VLS) to determine these parameters without needing to assume a reduced scattering coefficient (μ's). This problem is solved by appropriate calibrations. Compared to near-infrared spectroscopy (NIRS), OxyVLS determines the oxygenation in a much smaller more superficial volume of tissue, which is useful in many clinical cases. OxyVLS was validated in liquid phantoms with known StO2, [tHb], and μ's and compared to frequency domain NIRS as a reliable reference. OxyVLS showed a high accuracy for all the mentioned parameters and was even able to measure μ's. Thus, OxyVLS was successfully tested in vitro.