<p>A slice selection gradient magnetic field used in a pulse sequence for generating a spin echo signal is applied in such a fashion that its polarity at the time of a 90° pulse becomes opposite to the one at the time of 180° pulse, in order to expand a dynamic range of blood flow speed measurement. When the blood flow speed contains a component in a slice vertical direction, the gradient magnetic field in the slice vertical direction is adjusted so that the phase changes of two sets of flow encoded pulses contained in the slice vertical direction are opposite to each other.</p><p>The flow speed in the direction of the read-out gradient magnetic field, which is a lateral direction of the slide plane, is purely measured by cancelling influences of the flow in the slice vertical direction.</p>
