Phase contrast magnetic resonance images are produced using interleaved spiral k-space scanning with a bipolar phase contrast gradient. Spiral scanning is configured so that acquisition impulse response defines a central alias free portion in a partial field of view, and signal acquisition is arranged so that moving spins are contained with this central alias free portion. First and second signals are acquired with alternate phase encodings, and a complex difference of the acquired signals is obtained. The complex difference is substantially free of aliasing artifacts within the central portion.