We investigated the feasibility of performing black-blood MR angiography (MRA) with the gradient and spin-echo (GRASE) pulse sequence. Phantom experiments and human testing were conducted, and the results were compared with those of turbo spin-echo (TSE). We demonstrated that both techniques are abl
Mechanisms of flow-induced signal loss in MR angiography
✍ Scribed by Steven N. Urchuk; Donald B. Plewes
- Book ID
- 102905175
- Publisher
- John Wiley and Sons
- Year
- 1992
- Tongue
- English
- Weight
- 963 KB
- Volume
- 2
- Category
- Article
- ISSN
- 1053-1807
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✦ Synopsis
Abstract
Mechanisms of signal loss in magnetic resonance angiography were studied with a stenotic flow phantom. The results indicate that while signal loss induced by mean fluid motions is localized about the stenosis, the fluctuating component of fluid motion induces signal loss over a much larger region, primarily distal to the stenosis. For both motion components, use of gradient moment nulling (GMN) above first order was found to be an ineffective means of reducing signal loss. In contrast, shortened gradient durations were found to reduce signal loss substantially. However, though a zeroth‐order gradient is generally of the shortest duration, use of a slightly longer, first‐order gradient was found to be the most robust means of reducing signal loss.
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