## Abstract Diffusion‐weighted images acquired with the echo‐planar imaging technique are highly sensitive to eddy current induced geometric distortions that vary with the magnitude and direction of the diffusion sensitizing gradients. Such distortions cause misalignment of images acquired with dif
Elimination of eddy current artifacts in diffusion-weighted echo-planar images: The use of bipolar gradients
✍ Scribed by Andrew L. Alexander; Jay S. Tsuruda; Dennis L. Parker
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 683 KB
- Volume
- 38
- Category
- Article
- ISSN
- 0740-3194
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Small gradient fields resulting from incompletely canceled eddy currents can cause geometric distortion in echo‐planar images. Although this distortion is negligible in most echo‐planar applications, the large gradient pulses used in diffusion‐weighted echo‐planar imaging can result in significant image distortion. In this report, it is shown that this distortion can be significantly reduced by the application of bipolar gradient waveforms. Both bipolar diffusion‐sensitizing gradients and an inverted gradient preparatory pulse were examined for minimizing the eddy currents responsible for these distortions.
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