Angiographic Imaging with 2D RF Pulses

Magnetic resonance angiography (MRA) was performed by using RF pulses designed to excite a limited spatial extent in two orthogonal directions. The restriction in the second spatial dimension can be used to increase inflow enhancement and to improve small field‐of‐view imaging. A rectangular excitation was produced with an “echo‐planar” k‐space trajectory and a sine‐modulated RF waveform. In vivo images have demonstrated that vessels are more clearly delineated with the two‐dimensional excitation. Aliasing artifacts in small field‐of‐view imaging are significantly reduced, although in some cases complete elimination is not possible due to the nature of the gradient trajectory.

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