1. An image processing apparatus comprising: a calculation-image creating unit that creates a calculation image including velocity components of a Cerebrospinal Fluid (CSF) flowing inside a subject with respect to each of a plurality of images obtained by repeating imaging a plurality of number of times according to an imaging method capable of obtaining the velocity components; a statistic-image creating unit that calculates statistics indicating velocity variation of the CSF by same position on calculation images by using a plurality of calculation images created by the calculation-image creating unit, and creates a statistic image indicating a distribution of calculated statistics; a statistics display unit that displays the distribution of the statistics according to the statistic image created by the statistic-image creating unit.