Article
Radiology, Nuclear Medicine & Medical Imaging
Yuxin Hu, Debra M. Ikeda, Sarah M. Pittman, Dilan Samarawickrama, Arnaud Guidon, Jarrett Rosenberg, Shu-tian Chen, Satoko Okamoto, Bruce L. Daniel, Brian A. Hargreaves, Catherine J. Moran
Summary: Multishot DWI methods, particularly shot-LLR, offer improved image quality and resolution over single-shot DWI in breast imaging. The quality of multishot DWI images improves with an increased number of shots.
JOURNAL OF MAGNETIC RESONANCE IMAGING
(2021)
Article
Computer Science, Artificial Intelligence
Alexis Reymbaut, Alex Valcourt Caron, Guillaume Gilbert, Filip Szczepankiewicz, Markus Nilsson, Simon K. Warfield, Maxime Descoteaux, Benoit Scherrer
Summary: Diffusion tensor imaging provides increased sensitivity to microstructural tissue changes compared to conventional anatomical imaging, but presents limited specificity. To address this issue, the DIAMOND model subdivides voxel content into diffusion compartments and estimates compartmental non-central matrix-variate Gamma distributions of diffusion tensors. Incorporating tensor-valued diffusion encoding, the Magic DIAMOND model demonstrates improved accuracy in estimating brain microstructural features, particularly in regions of fiber crossing.
MEDICAL IMAGE ANALYSIS
(2021)
Article
Physics, Multidisciplinary
Samo Lasic, Nadira Yuldasheva, Filip Szczepankiewicz, Markus Nilsson, Matthew Budde, Erica Dall'Armellina, Juergen E. Schneider, Irvin Teh, Henrik Lundell
Summary: Diffusion encoding with free gradient waveforms can provide increased microstructural specificity. In cardiac applications, considering the effects of time-dependent diffusion and using different b-tensor shapes and motion compensation can provide additional tissue information.
FRONTIERS IN PHYSICS
(2022)
Article
Multidisciplinary Sciences
Ricardo Rios-Carrillo, Alonso Ramirez-Manzanares, Hiram Luna-Munguia, Mirelta Regalado, Luis Concha
Summary: Diffusion-weighted magnetic resonance imaging (DW-MRI) is a non-invasive technique sensitive to microstructural geometry in neural tissue and useful for detecting neuropathology. Tensor-valued diffusion encoding schemes (b-tensor) enrich the microstructural data obtained from DW-MRI. This study explores the application of machine learning in analyzing b-tensor encoding data to detect histopathology and neurodegeneration.
Article
Radiology, Nuclear Medicine & Medical Imaging
Elisa Marchetto, Kevin Murphy, Stefan L. L. Glimberg, Daniel Gallichan
Summary: This study investigated the artifacts arising from different types of head motion in brain MR images and how well these artifacts can be compensated using retrospective correction based on two different motion-tracking techniques. The study found that image quality could be recovered in cases of stepwise and slow diagonal motion using both motion estimation techniques. However, both methods struggled to correct for all motion artifacts in the case of circular motion.
MAGNETIC RESONANCE IN MEDICINE
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Filip Szczepankiewicz, Jens Sjolund, Erica Dall'Armellina, Sven Plein, Jurgen E. Schneider, Irvin Teh, Carl-Fredrik Westin
Summary: The proposed gradient waveform design is more flexible and efficient than previous methods, allowing for accurate diffusion encoding in tissues with motion. The approach includes compensation for concomitant gradient effects and can vastly improve data quality when applied in vivo.
MAGNETIC RESONANCE IN MEDICINE
(2021)
Article
Radiology, Nuclear Medicine & Medical Imaging
Liangyou Liu, Zhaotong Li, Zeru Zhang, Yifan Xia, Sha Li, Song Gao
Summary: The study aimed to identify a reliable diffusion gradient encoding scheme (DGES) based on the golden ratio (GR) to precisely estimate DTI parameters of partially acquired datasets due to subject motion, showing lower error propagation sensitivity compared to other encoding schemes.
JOURNAL OF MAGNETIC RESONANCE IMAGING
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Christopher T. Nguyen, Anthony G. Christodoulou, Jaume Coll-Font, Sen Ma, Yibin Xie, Timothy G. Reese, Choukri Mekkaoui, Gregory D. Lewis, Xiaoming Bi, David E. Sosnovik, Debiao Li
Summary: The study successfully developed a novel free-breathing cardiac DT-MRI approach, M2-MT-MOCO, capable of covering the entire left ventricle in 10 minutes. Results showed that this method preserved myocardial microstructure quantification compared to breath-held and single-slice acquisitions, making it feasible for use in heart failure patients.
MAGNETIC RESONANCE IN MEDICINE
(2021)
Article
Radiology, Nuclear Medicine & Medical Imaging
Ronald Mooiweer, Radhouene Neji, Sarah McElroy, Muhummad Sohaib Nazir, Reza Razavi, Amedeo Chiribiri, Sebastien Roujol
Summary: A fast respiratory navigator called fastNAV was developed for cardiac MR perfusion imaging, showing improved image quality and reduced heart displacement in real-time respiratory tracking.
MAGNETIC RESONANCE IN MEDICINE
(2021)
Article
Radiology, Nuclear Medicine & Medical Imaging
Zhiqiang Li, Melvyn B. Ooi, James A. Murchison, John P. Karis
Summary: The purpose of this study was to develop a rapid T*(2)-weighted MRI technique that can correct motion-induced artifacts, thereby improving scan time and motion robustness in the emergency department. The researchers implemented a 2D gradient-echo-based multishot EPI technique with a navigator echo to estimate motion-induced errors and correct them retrospectively. Preliminary clinical results showed that the proposed technique effectively corrected motion-induced artifacts and improved lesion conspicuity, making it a competitive alternative to traditional T*(2)-weighted MRI techniques for brain studies in the emergency department.
MAGNETIC RESONANCE IN MEDICINE
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Johan Berglund, Adam van Niekerk, Henric Ryden, Tim Sprenger, Enrico Avventi, Ola Norbeck, Stefan L. Glimberg, Oline V. Olesen, Stefan Skare
Summary: This study utilized an optical markerless tracking system for real-time rigid body motion correction during scanning, enabling motion-robust diffusion weighted imaging of the brain. Prospective motion correction with dynamic ghost correction allowed for high quality DWI images in the presence of fast and continuous motion within a 10 degrees range.
MAGNETIC RESONANCE IN MEDICINE
(2021)
Article
Chemistry, Physical
Laura Scalfi, Domenico Vitali, Henrik Kiefer, Roland R. Netz
Summary: Finite-size effects pose challenges in molecular dynamics simulations due to their significant impact on computed static and dynamic properties, particularly diffusion constants, friction coefficients, and time- or frequency-dependent response functions. This study investigates the influence of periodic boundary conditions on velocity autocorrelation function and frequency-dependent friction of particles in a fluid, revealing significant effects on long-time behavior starting at the picosecond timescale. An analytical correction is developed to subtract the periodic boundary condition effects, thereby uncovering power-law long-time tails of the memory kernel and velocity autocorrelation function in liquid water and a Lennard-Jones fluid even with small simulation boxes.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Ke Zhang, Simon M. F. Triphan, Felix T. Kurz, Christian H. Ziener, Hans-Ulrich Kauczor, Heinz-Peter Schlemmer, Oliver Sedlaczek
Summary: This study applies a navigator-based slice tracking method to compensate for respiratory motion in kidney vessel architecture imaging. The results show that this technique accurately calculates motion and adjusts slice positioning in real-time, improving microvasculature evaluation in kidney diseases.
MAGNETIC RESONANCE IMAGING
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Jaume Coll-Font, Shi Chen, Robert Eder, Yiling Fang, Qiao Joyce Han, Maaike van den Boomen, David E. Sosnovik, Choukri Mekkaoui, Christopher T. Nguyen
Summary: Retrospective respiratory phase estimation with LE-based DisCo and motion compensation in free-breathing cardiac DTI significantly reduced geometric distortion and improved alignment within and across slices.
MAGNETIC RESONANCE IN MEDICINE
(2022)
Article
Neurosciences
Yung-Chin Hsua, Wen-Yih Isaac Tseng
Summary: This paper proposes a registration-based algorithm to correct various distortions or artifacts commonly observed in diffusion-weighted magnetic resonance images. The algorithm uses anatomical images and a pseudo diffusion MRI data for registration, and estimates the models of artifacts simultaneously. The evaluation shows that the method accurately estimates model parameters and effectively reduces artifacts. This method is beneficial for most dMRI data, especially those acquired without additional field maps or reverse phase-encoding images.