Dataset Information

Variability of myocardial perfusion dark rim Gibbs artifacts due to sub-pixel shifts.

ABSTRACT:

Background

Gibbs ringing has been shown as a possible source of dark rim artifacts in myocardial perfusion studies. This type of artifact is usually described as transient, lasting a few heart beats, and localised in random segments of the myocardial wall. Dark rim artifacts are known to be unpredictably variable. This article aims to illustrate that a sub-pixel shift, i.e. a small displacement of the pixels with respect to the endocardial border, can result in different Gibbs ringing and hence different artifacts. Therefore a hypothesis for one cause of dark rim artifact variability is given based on the sub-pixel position of the endocardial border. This article also demonstrates the consequences for Gibbs artifacts when two different methods of image interpolation are applied (post-FFT interpolation, and pre-FFT zero-filling).

Results

Sub-pixel shifting of in vivo perfusion studies was shown to change the appearance of Gibbs artifacts. This effect was visible in the original un-interpolated images, and in the post-FFT interpolated images. The same shifted data interpolated by pre-FFT zero-filling exhibited much less variability in the Gibbs artifact. The in vivo findings were confirmed by phantom imaging and numerical simulations.

Conclusion

Unless pre-FFT zero-filling interpolation is performed, Gibbs artifacts are very dependent on the position of the subendocardial wall within the pixel. By introducing sub-pixel shifts relative to the endocardial border, some of the variability of the dark rim artifacts in different myocardial segments, in different patients and from frame to frame during first-pass perfusion due to cardiac and respiratory motion can be explained. Image interpolation by zero-filling can be used to minimize this dependency.

SUBMITTER: Ferreira P

PROVIDER: S-EPMC2693509 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature

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Publications

Variability of myocardial perfusion dark rim Gibbs artifacts due to sub-pixel shifts.

Ferreira Pedro P Gatehouse Peter P Kellman Peter P Bucciarelli-Ducci Chiara C Firmin David D

Journal of cardiovascular magnetic resonance : official journal of the Society for Cardiovascular Magnetic Resonance 20090527

<h4>Background</h4>Gibbs ringing has been shown as a possible source of dark rim artifacts in myocardial perfusion studies. This type of artifact is usually described as transient, lasting a few heart beats, and localised in random segments of the myocardial wall. Dark rim artifacts are known to be unpredictably variable. This article aims to illustrate that a sub-pixel shift, i.e. a small displacement of the pixels with respect to the endocardial border, can result in different Gibbs ringing an ...[more]

PMID: 19473492

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Dataset Information

Variability of myocardial perfusion dark rim Gibbs artifacts due to sub-pixel shifts.

Background

Results

Conclusion

Publications

Variability of myocardial perfusion dark rim Gibbs artifacts due to sub-pixel shifts.

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