This paper has built up the mathematical model for velocity measurement of nail fold microcirculation.

It pointed out that three factors should be taken into acdcount

i. e.

the flow direction absoluted displacement and wobbling. After presenting the temparal registration method of nailfold microcirculation image series

a fast and accurate registration of nailfold capillaries to compensate the wobbling and deformation is realized. Through motion analysis and based on registration we achieve velocity measurement without principle errors for the first time. The actual measurements verified the effectiveness of our method.