Optical Properties of Circulating Human Blood in the Wavelength Range 400-2500 nm

Knowledge about the optical properties and of human blood plays an important role for many diagnostic and therapeutic applications in laser medicine and medical diagnostics. They strongly depend on physiological parameters such as oxygen saturation, osmolarity, flow conditions, haematocrit, etc. The integrating sphere technique and inverse Monte Carlo simulations were applied to measure and of circulating human blood. At 633 nm the optical properties of human blood with a haematocrit of 10 and an oxygen saturation of 98 were found to be for for and for the factor. An increase of the haematocrit up to 50 lead to a linear increase of absorption and reduced scattering. Variations in osmolarity and wall shear rate led to changes of all three parameters while variations in the oxygen saturation only led to a significant change of the absorption coefficient. A spectrum of all three parameters was measured in the wavelength range 400-2500 nm for oxygenated and deoxygenated blood, showing that blood absorption followed the absorption behavior of haemoglobin and water. The scattering coefficient decreased for wavelengths above 500 nm with approximately the factor was higher than 0.9 over the whole wavelength range. ©