Quantitative flow measurement with the fast Fourier flow technique.

The fast Fourier flow method of magnetic resonance (MR) imaging offers a fast and efficient way of measuring quantitative flow for velocities within the range from several millimeters per second to more than 1 m/sec. When fast Fourier flow imaging is used in combination with echocardiographic gating, arterial flow can be determined and velocity versus time profiles can be generated. Because of the high spatial resolution, down to 0.3 mm, detailed examination of flow profiles is possible even in smaller vessels. The method works equally well on a low-field-strength system operating at 0.23 T and on a high-field-strength system with 4.7-T field strength. Since the experiment is very fast, with acquisition times ranging from 4 seconds for a single-section experiment to about 4 minutes for the electrocardiographically gated variant, it can easily be combined with a conventional MR imaging examination.