PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 7500889

Correction of motional artifacts in diffusion-weighted images using a reference phase map.

A M Uluğ·P B Barker·P C van Zijl
View original source ↗Export metadata ↓

Abstract

A method of correcting motional artifacts in diffusion-weighted images is described. Motion causes changes in the phase of the k-space NMR signal and thereby introduces positional shifts (or ghosts) in the spatial domain. By correcting the phase of the NMR signal before Fourier transformation, the image sharpness is greatly enhanced. The new method measures the phases of the NMR signal once and stores this phase information in a phase map. Subsequent images with motional artifacts are corrected during postprocessing using this reference phase map.

Explore related subjects

ArtifactsBrainHumansImage EnhancementMagnetic Resonance SpectroscopyMovementJournal ArticleResearch Support, U.S. Gov't, P.H.S.

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A M Uluğ, P B Barker, P C van Zijl. 1995. Correction of motional artifacts in diffusion-weighted images using a reference phase map.. https://doi.org/10.1002/mrm.1910340327

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2026

Striping artifact removal in VisiumHD data through nuclear counts modeling.

MOTIVATION: 10x Genomics VisiumHD enables spatial transcriptomics at 2 µm × 2 µm resolution but exhibits slide-specific, non-periodic striping artifacts due to lane-width variability. These multiplicative row/column effects distort bin total counts and can bias downstream analyses. The state-of-the-art destriping approach is the normalization procedure used as a preprocessing step in bin2cell; it applies sequential high-quantile row- then column-wise normalization, which is asymmetric and can introduce edge effects/macro-stripes and distortions of large-scale total-count structure. RESULTS: We propose a statistical destriping approach that leverages nuclei segmentation from the co-registered H&E image. Assuming transcript abundance is constant within each nucleus, we model bin counts with a negative binomial distribution whose mean is a product of a nucleus-specific concentration and row- and column-specific stripe-factors reflecting lane-width variation. We fit all parameters in a generalized linear modeling framework with cross-validated regularization on stripe-factors and iterative dispersion estimation, and use the fitted parameters to correct the observed counts into a destriped image. On synthetic data with known ground truth, our method improves stripe-factor estimation accuracy and reduces error in corrected counts relative to bin2cell and bin2cell-derived baselines. Across four public VisiumHD slides, it consistently lowers striping intensity while substantially better preserving biological signal present in the large-scale global count structure and avoiding the artifacts introduced by other methods. AVAILABILITY AND IMPLEMENTATION: All source code and links to publicly available data used for this study are available at https://github.com/paolamalsot/destriping-GLM.

Artifacts↗
PubMed2008

Impairment of echocardiographic acoustic window caused by breast implants.

Cosmetic breast implants are increasing in popularity. The presence of a breast implant overlying the anterior mediastinal space as a cause of impairment of the echocardiographic acoustic window has not been described previously. Here, we report three cases with significant impairment of echocardiographic acoustic window caused by breast implants. Clinicians should be aware of this interference and women should be informed of this dilemma before considering this cosmetic surgery.

Artifacts↗