Laser Doppler microscope for high accuracy velocity measurement of microcirculation

The velocity of red blood cells in the microcirculation of rat mesenteries was measured by using a laser Doppler microscope (LDM). The LDM system must be improved to provide accurate measurement, because there are some inherent disturbances on measuring the flow velocity in a microscopic area. The authors investigate the spurious Doppler signals, which are the most serious problem in LDM measurement, and develop an optical arrangement for eliminating the effect of spurious components. In vitro and in vivo microscopic flow measurements showed that the impaired system provides high-accuracy velocity measurement for a microscopic area.<>