Unenhanced 3D Ghost MR Angiography by Toggled Systolic and Diastolic Imaging

Introduction: Ghost magnetic resonance angiography (MRA) is a new method for angiography that suppresses background tissue without subtraction. The method is predicated on the creation of arterial ghost artifacts within a region containing no MR signal (e.g. air), and can be used for both unenhanced and contrast-enhanced MRA. When used for unenhanced MRA, cardiac gating is not required. This can be a substantial advantage compared with previously reported unenhanced MRA methods. However, it is not possible to rotate the ungated MRA from the orientation in which it was acquired. We report an alternative, ECG-gated approach for ghost MRA that enables the creation of multiple projections and also reduces scan time. We tested the hypothesis that, as a result of better suppression of background signal intensity, gated Ghost MRA improves vessel conspicuity compared with a conventional subtraction-based unenhanced MRA method.