Correction of phase wrapping in magnetic resonance imaging

In phase reconstruction MR imaging, e.g., for velocity measurement, phase shifts beyond +/- pi radians will "wrap around" to smaller apparent phases. Such large phase shifts could arise either due to large background (non-flow-related) phase variations or due to large velocity-induced phase shifts. For sufficiently smooth phase variation, such discontinuities can be automatically recognized and corrected, thus restoring the correct phase values and extending the effective dynamic range of such phase imaging techniques.