样式: 排序: IF: - GO 导出 标记为已读
-
Integrating data distribution prior via Langevin dynamics for end‐to‐end MR reconstruction Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Jing Cheng, Zhuo‐Xu Cui, Qingyong Zhu, Haifeng Wang, Yanjie Zhu, Dong Liang
PurposeTo develop a novel deep learning‐based method inheriting the advantages of data distribution prior and end‐to‐end training for accelerating MRI.MethodsLangevin dynamics is used to formulate image reconstruction with data distribution before facilitate image reconstruction. The data distribution prior is learned implicitly through the end‐to‐end adversarial training to mitigate the hyper‐parameter
-
Intra‐scan RF power amplifier drift correction Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Ali Aghaeifar, Dario Bosch, Rahel Heule, Sydney Williams, Philipp Ehses, Franck Mauconduit, Klaus Scheffler
PurposeThe drift in radiofrequency (RF) power amplifiers (RFPAs) is assessed and several contributing factors are investigated. Two approaches for prospective correction of drift are proposed and their effectiveness is evaluated.MethodsRFPA drift assessment encompasses both intra‐pulse and inter‐pulse drift analyses. Scan protocols with varying flip angle (FA), RF length, and pulse repetition time
-
A 3D dual‐echo spiral sequence for simultaneous dynamic susceptibility contrast and dynamic contrast‐enhanced MRI with single bolus injection Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Zhiqiang Li, Dinghui Wang, Melvyn B. Ooi, Poonam Choudhary, Sudarshan Ragunathan, John P. Karis, James G. Pipe, C. Chad Quarles, Ashley M. Stokes
PurposePerfusion MRI reveals important tumor physiological and pathophysiologic information, making it a critical component in managing brain tumor patients. This study aimed to develop a dual‐echo 3D spiral technique with a single‐bolus scheme to simultaneously acquire both dynamic susceptibility contrast (DSC) and dynamic contrast‐enhanced (DCE) data and overcome the limitations of current EPI‐based
-
Reduced cross‐scanner variability using vendor‐agnostic sequences for single‐shell diffusion MRI Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Qiang Liu, Lipeng Ning, Imam Ahmed Shaik, Congyu Liao, Borjan Gagoski, Berkin Bilgic, William Grissom, Jon‐Fredrik Nielsen, Maxim Zaitsev, Yogesh Rathi
PurposeTo reduce the inter‐scanner variability of diffusion MRI (dMRI) measures between scanners from different vendors by developing a vendor‐neutral dMRI pulse sequence using the open‐source vendor‐agnostic Pulseq platform.MethodsWe implemented a standard EPI based dMRI sequence in Pulseq. We tested it on two clinical scanners from different vendors (Siemens Prisma and GE Premier), systematically
-
An extended phase graph‐based framework for DANTE‐SPACE simulations including physiological, temporal, and spatial variations Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Matthijs H. S. de Buck, Peter Jezzard, Aaron T. Hess
PurposeThe delay alternating with nutation for tailored excitation (DANTE)–sampling perfection with application‐optimized contrasts (SPACE) sequence facilitates 3D intracranial vessel wall imaging with simultaneous suppression of blood and CSF. However, the achieved image contrast depends closely on the selected sequence parameters, and the clinical use of the sequence is limited in vivo by observed
-
Measuring CSF shunt flow with MRI using flow enhancement of signal intensity (FENSI) Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Mingxiao Zhang, William C. Olivero, Jason M. Huston, Suguna Pappu, Paul M. Arnold, Arundhati Biswas, Aaron T. Anderson, Bradley P. Sutton
PurposeTo develop and validate a noninvasive imaging technique for accurately assessing very slow CSF flow within shunt tubes in pediatric patients with hydrocephalus, aiming to identify obstructions that might impede CSF drainage.Theory and MethodsA simulation of shunt flow enhancement of signal intensity (shunt‐FENSI) signal is used to establish the relationship between signal change and flow rate
-
TensorFit: A torch‐based tool for ultrafast metabolite fitting of large MRSI data sets Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Federico Turco, Milena Capiglioni, Guodong Weng, Johannes Slotboom
PurposeTo introduce a tool (TensorFit) for ultrafast and robust metabolite fitting of MRSI data based on Torch's auto‐differentiation and optimization framework.MethodsTensorFit was implemented in Python based on Torch's auto‐differentiation to fit individual metabolites in MRS spectra. The underlying time domain and/or frequency domain fitting model is based on a linear combination of metabolite spectroscopic
-
Inline automatic quality control of 2D phase‐contrast flow MRI for subject‐specific scan time adaptation Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Pierre Daudé, Rajiv Ramasawmy, Ahsan Javed, Robert J. Lederman, Kelvin Chow, Adrienne E. Campbell‐Washburn
PurposeTo develop an inline automatic quality control to achieve consistent diagnostic image quality with subject‐specific scan time, and to demonstrate this method for 2D phase‐contrast flow MRI to reach a predetermined SNR.MethodsWe designed a closed‐loop feedback framework between image reconstruction and data acquisition to intermittently check SNR (every 20 s) and automatically stop the acquisition
-
Flexible metasurface for improving brain imaging at 7T Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Vladislav Koloskov, Wyger M. Brink, Andrew G. Webb, Alena Shchelokova
PurposeUltra‐high field MRI offers unprecedented detail for noninvasive visualization of the human brain. However, brain imaging is challenging at 7T due to the B field inhomogeneity, which results in signal intensity drops in temporal lobes and a bright region in the brain center. This study aims to evaluate using a metasurface to improve brain imaging at 7T and simplify the investigative workflow
-
High‐field downfield MR spectroscopic imaging in the human brain Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 İpek Özdemir, Semra Etyemez, Peter B. Barker
PurposeTo investigate the feasibility of downfield MR spectroscopic imaging (DF‐MRSI) in the human brain at 7T.MethodsA 7T DF‐MRSI pulse sequence was implemented based on the previously described methodology at 3T, with 3D phase‐encoding, spectral‐spatial excitation, and frequency selective refocusing. Data were pre‐processed followed by analysis using the “LCModel” software package, and metabolite
-
Hyperpolarized 15N caffeine, a potential probe of liver function and perfusion Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Cornelius von Morze, Ashley Shaw, Tyler Blazey
PurposeTo demonstrate hyperpolarization of 15N‐caffeine and report exploratory findings as a potential probe of liver function and perfusion.MethodsAn amorphous formulation of [1,3‐15N2]caffeine was developed for hyperpolarization via dissolution dynamic nuclear polarization. Polarizer hardware was augmented to support monitoring of solid‐state 15N MR signals during the buildup of hyperpolarization
-
In vivo B1+ enhancement of calf MRI at 7 T via optimized flexible metasurfaces Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-12 Paul S. Jacobs, Neil Wilson, Wyger Brink, Anshuman Swain, Ryan Armbruster, Aniketh Hanumapur, M. Dylan Tisdall, John Detre, Ravi Prakash Reddy Nanga, Mark A. Elliott, Ravinder Reddy
PurposeUltrahigh field (≥7 T) MRI is at the cutting edge of medical imaging, enabling enhanced spatial and spectral resolution as well as enhanced susceptibility contrast. However, transmit () field inhomogeneity due to standing wave effects caused by the shortened RF wavelengths at 7 T is still a challenge to overcome. Novel hardware methods such as dielectric pads have been shown to improve the field
-
Current methods for hyperpolarized [1-13C]pyruvate MRI human studies Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Peder E. Z. Larson, Jenna M. L. Bernard, James A. Bankson, Nikolaj Bøgh, Robert A. Bok, Albert P. Chen, Charles H. Cunningham, Jeremy W. Gordon, Jan-Bernd Hövener, Christoffer Laustsen, Dirk Mayer, Mary A. McLean, Franz Schilling, James B. Slater, Jean-Luc Vanderheyden, Cornelius von Morze, Daniel B. Vigneron, Duan Xu
MRI with hyperpolarized (HP) 13C agents, also known as HP 13C MRI, can measure processes such as localized metabolism that is altered in numerous cancers, liver, heart, kidney diseases, and more. It has been translated into human studies during the past 10 years, with recent rapid growth in studies largely based on increasing availability of HP agent preparation methods suitable for use in humans.
-
Boosting reproducible research practices with the Repeat It With Me: Reproducibility Team Challenge Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Laura Bortolotti, Sophie Schauman, Maria Eugenia Caligiuri
Reaching high standards of reproducibility, repeatability, and replicability in published literature ensures reliability in research outcomes. This, in turn, influences patient care and pivots medical research trajectories. The credibility of published work is therefore crucial to guide researchers on how to build on their findings and prevent undermining trust in the scientific community and the broader
-
Assessment of arterial pulsatility of cerebral perforating arteries using 7T high‐resolution dual‐VENC phase‐contrast MRI Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Jianing Tang, Soroush Heidari Pahlavian, Elizabeth Joe, Maria Tereza Gamez, Tianrui Zhao, Samantha J. Ma, Jin Jin, Steven Yong Cen, Helena C. Chui, Lirong Yan
PurposeDirectly imaging the function of cerebral perforating arteries could provide valuable insight into the pathology of cerebral small vessel diseases (cSVD). Arterial pulsatility has been identified as a useful biomarker for assessing vascular dysfunction. In this study, we investigate the feasibility and reliability of using dual velocity encoding (VENC) phase‐contrast MRI (PC‐MRI) to measure
-
A theoretical framework to investigate the effect of high permittivity materials in MRI using anatomy‐mimicking cylinders Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Vincenzo Miranda, Giuseppe Ruello, Riccardo Lattanzi
PurposeRecent numerical and empirical results proved that high permittivity materials (HPM) used in pads placed near the subject or directly integrated with coils can increase the SNR and reduce the specific absorption rate (SAR) in MRI. In this paper, we propose an analytical investigation of the effect on the magnetic field distribution of a layer of HPM surrounding an anatomy‐mimicking cylindrical
-
Submillimeter balanced SSFP BOLD–functional MRI accelerated with 3D stack‐of‐spirals at 9.4 T Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Praveen Iyyappan Valsala, Marten Veldmann, Dario Bosch, Klaus Scheffler, Philipp Ehses
PurposeThis work aims to improve the speed of balanced SSFP (bSSFP) acquisition with segmented 3D stack‐of‐spirals for functional brain studies at ultrahigh field.MethodsFunctional experiments were performed with an accelerated 3D stack‐of‐spirals sequence with water excitation for fat suppression. The resulting data were reconstructed using an iterative algorithm with corrections for system imperfections
-
Using a deep learning prior for accelerating hyperpolarized 13C MRSI on synthetic cancer datasets Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Zuojun Wang, Guanxiong Luo, Ye Li, Peng Cao
PurposeWe aimed to incorporate a deep learning prior with k‐space data fidelity for accelerating hyperpolarized carbon‐13 MRSI, demonstrated on synthetic cancer datasets.MethodsA two‐site exchange model, derived from the Bloch equation of MR signal evolution, was firstly used in simulating training and testing data, that is, synthetic phantom datasets. Five singular maps generated from each simulated
-
GPU‐accelerated Bloch simulations and MR‐STAT reconstructions using the Julia programming language Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Oscar van der Heide, Cornelis A. T. van den Berg, Alessandro Sbrizzi
PurposeMR‐STAT is a relatively new multiparametric quantitative MRI technique in which quantitative paramater maps are obtained by solving a large‐scale nonlinear optimization problem. Managing reconstruction times is one of the main challenges of MR‐STAT. In this work we leverage GPU hardware to reduce MR‐STAT reconstruction times. A highly optimized, GPU‐compatible Bloch simulation toolbox is developed
-
Age‐related differences in macromolecular resonances observed in ultra‐short‐TE STEAM MR spectra at 7T Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Guglielmo Genovese, Melissa Terpstra, Pavel Filip, Silvia Mangia, J. Riley McCarten, Laura S. Hemmy, Małgorzata Marjańska
PurposeTo understand how macromolecular content varies in the human brain with age in a large cohort of healthy subjects.MethodsIn‐vivo 1H‐MR spectra were acquired using ultra‐short TE STEAM at 7T in the posterior cingulate cortex. Macromolecular content was studied in 147 datasets from a cohort ranging in age from 19 to 89 y. Three fitting approaches were used to evaluate the macromolecular content:
-
Motion‐compensated diffusion encoding in multi‐shot human brain acquisitions: Insights using high‐performance gradients Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Eric Seth Michael, Franciszek Hennel, Klaas Paul Pruessmann
PurposeTo evaluate the utility of up to second‐order motion‐compensated diffusion encoding in multi‐shot human brain acquisitions.MethodsExperiments were performed with high‐performance gradients using three forms of diffusion encoding motion‐compensated through different orders: conventional zeroth‐order–compensated pulsed gradients (PG), first‐order–compensated gradients (MC1), and second‐order–compensated
-
Tailored and universal parallel transmit broadband pulses for homogeneous 3D excitation of the human heart at 7T Magn. Reson. Med. (IF 3.3) Pub Date : 2024-03-05 Christoph Stefan Aigner, Sebastian Dietrich‐Conzelmann, Max Lutz, Felix Krüger, Sebastian Schmitter
PurposeTo research and evaluate the performance of broadband tailored kT‐point pulses (TP) and universal pulses (UP) for homogeneous excitation of the human heart at 7T.MethodsRelative 3D ‐maps of the thorax were acquired from 29 healthy volunteers. TP and UP were designed using the small‐tip‐angle approximation for a different composition of up to seven resonance frequencies. TP were computed for
-
VICTR: Venous transit time imaging by changes in T1 relaxation Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-27 Wen Shi, Dengrong Jiang, Zhiyi Hu, Vivek Yedavalli, Yulin Ge, Abhay Moghekar, Hanzhang Lu
Abnormalities in cerebral veins are a common finding in many neurological diseases, yet there is a scarcity of MRI techniques to assess venous hemodynamic function. The present study aims to develop a noncontrast technique to measure a novel blood flow circulatory measure, venous transit time (VTT), which denotes the time it takes for water to travel from capillary to major veins.
-
Robust T2 estimation with balanced steady state free precession Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-27 Oliver Bieri, Claudia Weidensteiner, Carl Ganter
PurposeTo develop a novel signal representation for balanced steady state free precession (bSSFP) displaying its T2 independence on B1 and on magnetization transfer (MT) effects.MethodsA signal model for bSSFP is developed that shows only an explicit dependence (up to a scaling factor) on E2 (and, therefore, T2) and a novel parameter c (with implicit dependence on the flip angle and E1). Moreover,
-
Hand‐held electron spin resonance scanner for subcutaneous oximetry using OxyChip Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-27 Nir Almog, Oleg Zgadzai, Periannan Kuppusamy, Yehonatan Zur, Limor Baruch, Marcelle Machluf, Aharon Blank
PurposeElectron spin resonance (ESR) is used to measure oxygen partial pressure (pO2) in biological media with many clinical applications. Traditional clinical ESR involves large magnets that encompass the subject of measurement. However, certain applications might benefit from a scanner operating within local static magnetic fields. Our group recently developed such a compact scanner for transcutaneous
-
Stealth RF energy harvesting in MRI using selective shielding Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-27 Oskar Bjorkqvist, Klaas P. Pruessmann
PurposeTo utilize the transmit radiofrequency (RF) field in MRI as a power source, near or within the field of view but without affecting image quality or safety.MethodsPower harvesting is performed by RF induction in a resonant coil. Resulting RF field distortion in the subject is canceled by a selective shield that couples to the harvester while being transparent to the RF transmitter. Such shielding
-
Interventional device tracking under MRI via alternating current controlled inhomogeneities Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-23 Dogangun Uzun, Dursun Korel Yildirim, Christopher G. Bruce, Rim N. Halaby, Andrea E. Jaimes, Amanda Potersnak, Rajiv Ramasawmy, Adrienne E. Campbell‐Washburn, Robert J. Lederman, Ozgur Kocaturk
PurposeTo introduce alternating current‐controlled, conductive ink‐printed marker that could be implemented with both custom and commercial interventional devices for device tracking under MRI using gradient echo, balanced SSFP, and turbo spin‐echo sequences.MethodsTracking markers were designed as solenoid coils and printed on heat shrink tubes using conductive ink. These markers were then placed
-
Tensor denoising of quantitative multi-parameter mapping Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-18 Helge Herthum, Stefan Hetzer
Quantitative multi-parameter mapping (MPM) provides maps of physical quantities representing physiologically meaningful tissue characteristics, which allows to investigate microstructure-function relationships reflecting normal or pathologic processes in the brain. However, the achievable spatial resolution and stability of MPM for basic research or clinical applications is severely constrained by
-
Novel pore size-controlled, susceptibility matched, 3D-printed MRI phantoms Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-18 Velencia J. Witherspoon, Michal E. Komlosh, Dan Benjamini, Evren Özarslan, Nickolay Lavrik, Peter J. Basser
We report the design concept and fabrication of MRI phantoms, containing blocks of aligned microcapillaires that can be stacked into larger arrays to construct diameter distribution phantoms or fractured, to create a “powder-averaged” emulsion of randomly oriented blocks for vetting or calibrating advanced MRI methods, that is, diffusion tensor imaging, AxCaliber MRI, MAP-MRI, and multiple pulsed field
-
Quantitative measurement of mammographic density in breast‐tissue explants using portable NMR: Precision and accuracy Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-21 Satcha Foongkajornkiat, Kamil Sokolowski, James Stephenson, Thomas Lloyd, Honor J. Hugo, Erik W. Thompson, Konstantin I. Momot
PurposeSingle‐sided portable NMR (pNMR) has previously been demonstrated to be suitable for quantification of mammographic density (MD) in excised breast tissue samples. Here we investigate the precision and accuracy of pNMR measurements of MD ex vivo as compared with the gold standards.MethodsForty‐five breast‐tissue explants from 9 prophylactic mastectomy patients were measured. The relative tissue
-
Quasi‐steady‐state (QUASS) reconstruction enhances T1 normalization in apparent exchange‐dependent relaxation (AREX) analysis: A reevaluation of T1 correction in quantitative CEST MRI of rodent brain tumor models Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-21 Phillip Zhe Sun
PurposeThe apparent exchange‐dependent relaxation (AREX) analysis has been proposed as an effective means to correct T1 contribution in CEST quantification. However, it has been recognized that AREX T1 correction is not straightforward if CEST scans are not performed under the equilibrium condition. Our study aimed to test if quasi‐steady‐state (QUASS) reconstruction could boost the accuracy of the
-
Robust EMI elimination for RF shielding‐free MRI through deep learning direct MR signal prediction Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-20 Yujiao Zhao, Linfang Xiao, Jiahao Hu, Ed X. Wu
PurposeTo develop a new electromagnetic interference (EMI) elimination strategy for RF shielding‐free MRI via active EMI sensing and deep learning direct MR signal prediction (Deep‐DSP).MethodsDeep‐DSP is proposed to directly predict EMI‐free MR signals. During scanning, MRI receive coil and EMI sensing coils simultaneously sample data within two windows (i.e., for MR data and EMI characterization
-
The coax monopole antenna: A flexible end‐fed antenna for ultrahigh field transmit/receive arrays Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-20 Lyanne M. I. Budé, Bart R. Steensma, Irena Zivkovic, Alexander J. E. Raaijmakers
PurposeThe coax monopole antenna is presented for body imaging at 7 T. The antenna is fed at one end, eliminating the possibility of cable‐coil coupling and simplifying cable routing. Additionally, its flexibility improves loading to the subject.MethodsLike the coax dipole antenna, an interruption in the shield of the coaxial cable allows the current to extend to the outside of the shield, generating
-
Cardiac DTI using short‐axis PROPELLER: A feasibility study Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-20 Mehdi Sadighi, Danielle Kara, Dingheng Mai, Khoi Nguyen, Shi Chen, Deborah Kwon, Christopher Nguyen
PurposeWe aimed to develop a free‐breathing (FB) cardiac DTI (cDTI) method based on short‐axis PROPELLER (SAP) and M2 motion compensated spin‐echo EPI (SAP‐M2‐EPI) to mitigate geometric distortion and eliminate aliasing in acquired diffusion‐weighted (DW) images, particularly in patients with a higher body mass index (BMI).Theory and MethodsThe study involved 10 healthy volunteers whose BMI values
-
Motion compensated structured low-rank reconstruction for 3D multi-shot EPI Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-15 Xi Chen, Wenchuan Wu, Mark Chiew
The 3D multi-shot EPI imaging offers several benefits including higher SNR and high isotropic resolution compared to 2D single shot EPI. However, it suffers from shot-to-shot inconsistencies arising from physiologically induced phase variations and bulk motion. This work proposed a motion compensated structured low-rank (mcSLR) reconstruction method to address both issues for 3D multi-shot EPI.
-
Any-nucleus distributed active programmable transmit coil Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-11 Victor Han, Charlie P. Reeder, Miriam Hernández-Morales, Chunlei Liu
There are 118 known elements. Nearly all of them have NMR active isotopes and at least 39 different nuclei have biological relevance. Despite this, most of today's MRI is based on only one nucleus—1H. To facilitate imaging all potential nuclei, we present a single transmit coil able to excite arbitrary nuclei in human-scale MRI.
-
Improving quantitative MRI using self-supervised deep learning with model reinforcement: Demonstration for rapid T1 mapping Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-11 Wanyu Bian, Albert Jang, Fang Liu
This paper proposes a novel self-supervised learning framework that uses model reinforcement, REference-free LAtent map eXtraction with MOdel REinforcement (RELAX-MORE), for accelerated quantitative MRI (qMRI) reconstruction. The proposed method uses an optimization algorithm to unroll an iterative model-based qMRI reconstruction into a deep learning framework, enabling accelerated MR parameter maps
-
JUST-Net: Jointly unrolled cross-domain optimization based spatio-temporal reconstruction network for accelerated 3D myelin water imaging Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-11 Jae-Hun Lee, Jae-Yoon Kim, Kanghyun Ryu, Mohammed A. Al-masni, Tae Hyung Kim, Dongyeob Han, Hyun Gi Kim, Dong-Hyun Kim
We introduced a novel reconstruction network, jointly unrolled cross-domain optimization-based spatio-temporal reconstruction network (JUST-Net), aimed at accelerating 3D multi-echo gradient-echo (mGRE) data acquisition and improving the quality of resulting myelin water imaging (MWI) maps.
-
High SNR full brain relaxometry at 7T by accelerated MR-STAT Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-07 Edwin Versteeg, Hongyan Liu, Oscar van der Heide, Miha Fuderer, Cornelis A. T. van den Berg, Alessandro Sbrizzi
To demonstrate the feasibility and robustness of the Magnetic Resonance Spin TomogrAphy in Time-domain (MR-STAT) framework for fast, high SNR relaxometry at 7T.
-
Comparison of methods for intravoxel incoherent motion parameter estimation in the brain from flow-compensated and non-flow-compensated diffusion-encoded data Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-06 Oscar Jalnefjord, Isabella M. Björkman-Burtscher
Joint analysis of flow-compensated (FC) and non-flow-compensated (NC) diffusion MRI (dMRI) data has been suggested for increased robustness of intravoxel incoherent motion (IVIM) parameter estimation. For this purpose, a set of methods commonly used or previously found useful for IVIM analysis of dMRI data obtained with conventional diffusion encoding were evaluated in healthy human brain.
-
Getting the phase consistent: The importance of phase description in balanced steady-state free precession MRI of multi-compartment systems Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-06 Nils M. J. Plähn, Simone Poli, Eva S. Peper, Berk C. Açikgöz, Roland Kreis, Carl Ganter, Jessica A. M. Bastiaansen
Determine the correct mathematical phase description for balanced steady-state free precession (bSSFP) signals in multi-compartment systems.
-
B1+ inhomogeneity mitigation for diffusion weighted MRI at 7T using TR-FOCI pulses Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-06 Shahrokh Abbasi-Rad, Martijn A. Cloos, Jin Jin, Kieran O'Brien, Markus Barth
The purpose of this study is to improve the image quality of diffusion-weighted images obtained with a single RF transmit channel 7 T MRI setup using time-resampled frequency-offset corrected inversion (TR-FOCI) pulses to refocus the spins in a twice-refocused spin-echo readout scheme.
-
In vivo monitoring of renal tubule volume fraction using dynamic parametric MRI Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-06 Ehsan Tasbihi, Thomas Gladytz, Jason M. Millward, Joāo S. Periquito, Ludger Starke, Sonia Waiczies, Kathleen Cantow, Erdmann Seeliger, Thoralf Niendorf
The increasing incidence of kidney diseases is a global concern, and current biomarkers and treatments are inadequate. Changes in renal tubule luminal volume fraction (TVF) serve as a rapid biomarker for kidney disease and improve understanding of renal (patho)physiology. This study uses the amplitude of the long T2 component as a surrogate for TVF in rats, by applying multiexponential analysis of
-
Sidebands in CEST MR—How to recognize and avoid them Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-05 Jan-Rüdiger Schüre, Simon Weinmüller, Lukas Kamm, Kai Herz, Moritz Zaiss
Clinical scanners require pulsed CEST sequences to maintain amplifier and specific absorption rate limits. During off-resonant RF irradiation and interpulse delay, the magnetization can accumulate specific relative phases within the pulse train. In this work, we show that these phases are important to consider, as they can lead to unexpected artifacts when no interpulse gradient spoiling is performed
-
Effect of inhaled oxygen level on dynamic glucose-enhanced MRI in mouse brain Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-02 Jianpan Huang, Zilin Chen, Peter C. M. van Zijl, Lok Hin Law, Rohith Saai Pemmasani Prabakaran, Se Weon Park, Jiadi Xu, Kannie W. Y. Chan
To investigate the effect of inhaled oxygen level on dynamic glucose enhanced (DGE) MRI in mouse brain tissue and CSF at 3 T.
-
Self-supervised multicontrast super-resolution for diffusion-weighted prostate MRI Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-02 Batuhan Gundogdu, Milica Medved, Aritrick Chatterjee, Roger Engelmann, Avery Rosado, Grace Lee, Nisa C. Oren, Aytekin Oto, Gregory S. Karczmar
This study addresses the challenge of low resolution and signal-to-noise ratio (SNR) in diffusion-weighted images (DWI), which are pivotal for cancer detection. Traditional methods increase SNR at high b-values through multiple acquisitions, but this results in diminished image resolution due to motion-induced variations. Our research aims to enhance spatial resolution by exploiting the global structure
-
Dynamic field mapping and distortion correction using single-shot blip-rewound EPI and joint multi-echo reconstruction Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-02 Wenchuan Wu
To develop a method for dynamic ∆ B 0 $$ \Delta {B}_0 $$ mapping and distortion correction.
-
Universal modes: Calibration-free time-interleaved acquisition of modes Magn. Reson. Med. (IF 3.3) Pub Date : 2024-02-01 Simon Schmidt, Xiaoxuan He, Gregory J. Metzger
To introduce universal modes by applying the universal pulse concept to time-interleaved acquisition of modes (TIAMO), thereby achieving calibration-free B 1 + $$ {B}_1^{+} $$ inhomogeneity mitigation for body imaging at ultra-high fields.
-
Analytical corrections for B1-inhomogeneity and signal decay in multi-slice 2D spiral hyperpolarized 129Xe MRI using keyhole reconstruction Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-31 J. W. Plummer, R. Hussain, A. S. Bdaiwi, M. L. Costa, M. M. Willmering, J. Parra-Robles, Z. I. Cleveland, L. L. Walkup
Hyperpolarized xenon MRI suffers from heterogeneous coil bias and magnetization decay that obscure pulmonary abnormalities. Non-physiological signal variability can be mitigated by measuring and mapping the nominal flip angle, and by rescaling the images to correct for signal bias and decay. While flip angle maps can be calculated from sequentially acquired images, scan time and breath-hold duration
-
Quantification of the in vivo brain ultrashort-T2* component in healthy volunteers Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-30 Nikhil Deveshwar, Jingwen Yao, Misung Han, Nicholas Dwork, Xin Shen, Emil Ljungberg, Eduardo Caverzasi, Peng Cao, Roland Henry, Ari Green, Peder E. Z. Larson
Recent work has shown MRI is able to measure and quantify signals of phospholipid membrane-bound protons associated with myelin in the human brain. This work seeks to develop an improved technique for characterizing this brain ultrashort- T 2 ∗ $$ {\mathrm{T}}_2\ast $$ component in vivo accounting for T 1 $$ {\mathrm{T}}_1 $$ weighting.
-
Predictive uncertainty in deep learning–based MR image reconstruction using deep ensembles: Evaluation on the fastMRI data set Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-28 Thomas Küstner, Kerstin Hammernik, Daniel Rueckert, Tobias Hepp, Sergios Gatidis
To estimate pixel-wise predictive uncertainty for deep learning–based MR image reconstruction and to examine the impact of domain shifts and architecture robustness.
-
Model-based reconstruction for looping-star MRI Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-28 Haowei Xiang, Jeffrey A. Fessler, Douglas C. Noll
The aim of this study was to develop a reconstruction method that more fully models the signals and reconstructs gradient echo (GRE) images without sacrificing the signal to noise ratio and spatial resolution, compared to conventional gridding and model-based image reconstruction method.
-
Zero-DeepSub: Zero-shot deep subspace reconstruction for rapid multiparametric quantitative MRI using 3D-QALAS Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-28 Yohan Jun, Yamin Arefeen, Jaejin Cho, Shohei Fujita, Xiaoqing Wang, P. Ellen Grant, Borjan Gagoski, Camilo Jaimes, Michael S. Gee, Berkin Bilgic
To develop and evaluate methods for (1) reconstructing 3D-quantification using an interleaved Look-Locker acquisition sequence with T2 preparation pulse (3D-QALAS) time-series images using a low-rank subspace method, which enables accurate and rapid T1 and T2 mapping, and (2) improving the fidelity of subspace QALAS by combining scan-specific deep-learning-based reconstruction and subspace modeling
-
Frequency shifts of free water signals from compact bone: Simulations and measurements using a UTE-FID sequence Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-28 Anja Fischer, Petros Martirosian, Jürgen Machann, Bernd Fränkle, Fritz Schick
Free water in cortical bone is either contained in nearly cylindrical structures (mainly Haversian canals oriented parallel to the bone axis) or in more spherically shaped pores (lacunae). Those cavities have been reported to crucially influence bone quality and mechanical stability. Susceptibility differences between bone and water can lead to water frequency shifts dependent on the geometric characteristics
-
Unsupervised motion artifact correction of turbo spin-echo MRI using deep image prior Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-28 Jongyeon Lee, Hyunseok Seo, Wonil Lee, HyunWook Park
In MRI, motion artifacts can significantly degrade image quality. Motion artifact correction methods using deep neural networks usually required extensive training on large datasets, making them time-consuming and resource-intensive. In this paper, an unsupervised deep learning-based motion artifact correction method for turbo-spin echo MRI is proposed using the deep image prior framework.
-
Distinguishing metabolic signals of liver tumors from surrounding liver cells using hyperpolarized 13C MRI and gadoxetate Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-25 Shubhangi Agarwal, Jeremy Gordon, Robert A. Bok, Cornelius von Morze, Daniel B. Vigneron, John Kurhanewicz, Michael A. Ohliger
To use the hepatocyte-specific gadolinium-based contrast agent gadoxetate combined with hyperpolarized (HP) [1-13C]pyruvate MRI to selectively suppress metabolic signals from normal hepatocytes while preserving the signals arising from tumors.
-
Quantitative MRI reveals heterogeneous impacts of treatment on diseased bone marrow in a mouse model of myelofibrosis Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-24 Tanner H. Robison, Winston Lee, Kathryn E. Luker, Kristen Pettit, Moshe Talpaz, Thomas L. Chenevert, Brian D. Ross, Gary D. Luker
Analyzing bone marrow in the hematologic cancer myelofibrosis requires endpoint histology in mouse models and bone marrow biopsies in patients. These methods hinder the ability to monitor therapy over time. Preclinical studies typically begin treatment before mice develop myelofibrosis, unlike patients who begin therapy only after onset of disease. Using clinically relevant, quantitative MRI metrics
-
3T 31P/1H calf muscle coil for 1H and 31P MRI/MRS integrated with NIRS data acquisition Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-24 Bei Zhang, Daniel Lowrance, Manoj Kumar Sarma, Miles Bartlett, David Zaha, Michael D. Nelson, Anke Henning
Our aim was to design and build a 3T 31P/1H calf coil that is capable of providing both good 31P and 1H transmit and receive performance, as well as being capable of accommodating a near-infrared spectroscopy (NIRS) device for simultaneous NIRS data and MRI/MRS acquisition.
-
Functional activation of pyruvate dehydrogenase in human brain using hyperpolarized [1-13C]pyruvate Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-24 Maheen Zaidi, Junjie Ma, Binu P. Thomas, Salvador Peña, Crystal E. Harrison, Jun Chen, Sung-Han Lin, Kelley A. Derner, Jeannie D. Baxter, Jeff Liticker, Craig R. Malloy, Brenda Bartnik-Olson, Jae Mo Park
Pyruvate, produced from either glucose, glycogen, or lactate, is the dominant precursor of cerebral oxidative metabolism. Pyruvate dehydrogenase (PDH) flux is a direct measure of cerebral mitochondrial function and metabolism. Detection of [13C]bicarbonate in the brain from hyperpolarized [1-13C]pyruvate using carbon-13 (13C) MRI provides a unique opportunity for assessing PDH flux in vivo. This study
-
Referenceless Nyquist ghost correction outperforms standard navigator-based method and improves efficiency of in vivo diffusion tensor cardiovascular magnetic resonance Magn. Reson. Med. (IF 3.3) Pub Date : 2024-01-24 Zimu Huo, Ke Wen, Yaqing Luo, Radhouene Neji, Karl P. Kunze, Pedro F. Ferreira, Dudley J. Pennell, Andrew D. Scott, Sonia Nielles-Vallespin
The study aims to assess the potential of referenceless methods of EPI ghost correction to accelerate the acquisition of in vivo diffusion tensor cardiovascular magnetic resonance (DT-CMR) data using both computational simulations and data from in vivo experiments.