Shared k-space echo planar imaging with keyhole.

M Zaitsev; K Zilles; N J Shah

doi:10.1002/1522-2594(200101)45:1<109::aid-mrm1015>3.0.co;2-x

Home/Archive/PubMed

PubMed · 11146492

Shared k-space echo planar imaging with keyhole.

M Zaitsev·K Zilles·N J Shah

View original source ↗Export metadata ↓

Abstract

Time-dependent phenomena are of great interest, and researchers have sought to shed light on these processes with MRI, particularly in vivo. In this work, a new hybrid technique based on EPI and using the concept of keyhole imaging is presented. By sharing peripheral k-space data between images and acquiring the keyhole more frequently, it is shown that the spatial resolution of the reconstructed images can be maintained. The method affords a higher temporal resolution and is more robust against susceptibility and chemical-shift artifacts than single-shot EPI. The method, termed shared k-space echo planar imaging with keyhole (shared EPIK), has been implemented on a standard clinical scanner. Technical details, simulation results, phantom images, in vivo images, and fMRI results are presented. These results indicate that the new method is robust and may be used for dynamic MRI applications. Magn Reson Med 45:109-117, 2001.

Explore related subjects

Artifacts Brain Echo-Planar Imaging Humans Image Processing, Computer-Assisted Male Phantoms, Imaging Journal Article

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

M Zaitsev, K Zilles, N J Shah. 2001. Shared k-space echo planar imaging with keyhole.. https://doi.org/10.1002/1522-2594(200101)45%3A1%3C109%3A%3Aaid-mrm1015%3E3.0.co%3B2-x

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↗

PubMed2004

Impact of nano- and mesoscale particles on the performance of microcantilever-based sensors.

Microcantilever-based sensors comprise an emerging class of chemomechanical sensors. The crucial challenge for every new and promising sensing platform lies in its performance in complex mixtures. Since most biofluids are rich in particulates, we assessed the impact of particles in the liquid stream on the performance of microcantilever sensors operated in both deflection and resonance modes. For both detection modes, sensor response depends on the particle diameter, concentration, and velocity as well as the composition of a thin-film coating. The presence of particles in the fluid stream produce substantial scattering of the laser beam used to measure cantilever deflection. Thus, prior removal of particulate matter from biofluids is required for optimal performance of microcantilever-based biosensors.

Artifacts↗

PubMed2004

Signal irreproducibility in high-field solution magnetic resonance experiments caused by spin turbulence.

Turbulent spin dynamics arising from the joint action of radiation damping and the distant dipolar field are shown to generate irreproducible measurements in popular high-field, gradient-based magnetic resonance (MR) experiments, undermining the prevailing assumption of essentially predictable observables in MR. Sizeable fluctuations in echo amplitudes are reported and numerically simulated for pulsed gradient spin echo and stimulated echo diffusion measurements. The underlying microscopic dynamical instability is characterized by analysis of the finite-time Lyapunov exponents. Perturbations to the modulated magnetization are shown to render magic-angle gradients ineffective in suppressing signal fluctuations. Alternative approaches are suggested for cancelling out the feedback interactions leading to spin turbulence.

Artifacts↗