The complex difference method of phase-contrast MR angiography is affected not only by the degree of velocity encoding applied during the scan but also by the variance of the intravoxel velocity distribution. The reconstructed intensities of voxels with the same average flow rate but different varia
Comparison of phase-difference and complex-difference processing in phase-contrast MR angiography
✍ Scribed by Matt A. Bernstein; Yoshikazu Ikezaki
- Publisher
- John Wiley and Sons
- Year
- 1991
- Tongue
- English
- Weight
- 480 KB
- Volume
- 1
- Category
- Article
- ISSN
- 1053-1807
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The two main phase‐contrast reconstruction methods are phase difference and complex difference. The signal‐to‐noise ratio properties and relative advantages of the two techniques are discussed. It is argued that each processing method has applications in which it is superior, and guidelines are provided to determine those applications. It is demonstrated theoretically and experimentally that only the complex‐difference method is well suited for processing phase‐contrast slabs with use of a projection dephaser gradient.
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