5,317 results match your criteria Magnetic resonance imaging[Journal]


Evaluation of the sensitivity of Rρ MRI to pH and macromolecular density.

Magn Reson Imaging 2019 Feb 13. Epub 2019 Feb 13.

Department of Radiology, Box 218, University of Cambridge, Cambridge CB2 0QQ, United Kingdom; Cambridge University Hospitals NHS Foundation Trust, Addenbrooke's Hospital, Cambridge, United Kingdom, CB2 0QQ. Electronic address:

The tumor microenvironment is characteristically acidic and this extracellular acidosis is known to play a role in carcinogenesis and metastasis and can affect tumor chemosensitivity and radiosensitivity. Intracellular pH has been used as a possible biomarker of salvageable tissue in ischemic stroke. A non-invasive MRI-based approach for the determination and imaging of cerebral pH would be a powerful tool in cancer diagnosis and monitoring, as well as stroke treatment planning. Read More

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http://dx.doi.org/10.1016/j.mri.2019.02.004DOI Listing
February 2019

Prostate cancer treated with irreversible electroporation: MRI-based volumetric analysis and oncological outcome.

Magn Reson Imaging 2019 Feb 12. Epub 2019 Feb 12.

Department of Radiology, University College London Hospital NHS Foundation Trust, London, UK; Centre for Medical Imaging, University College London, London, UK.

Background: To assess multiparametric magnetic resonance imaging (mpMRI) characteristics in prostate cancer (PCa) before and after irreversible electroporation (IRE) and to investigate their correlation with the presence of post-operative recurrence of PCa.

Methods: MpMRI was performed in 30 men with PCa prior to treatment, after 10 days and at 6 months. An additional scan at 1 year was available for 18 men. Read More

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http://dx.doi.org/10.1016/j.mri.2019.02.003DOI Listing
February 2019

T2 mapping with 3.0 T MRI of the temporomandibular joint disc of patients with disc dislocation.

Magn Reson Imaging 2019 Feb 9. Epub 2019 Feb 9.

High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Lazarettgasse 14, 1090 Vienna, Austria; CD Laboratory for Clinical Molecular MR Imaging, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. Electronic address:

Introduction: T2 mapping, as a quantitative biochemical MRI-technique that provides information on water and collagen fiber content and composition, was shown to be clinically feasible for the evaluation of healthy temporomandibular joints.

Objectives: The aim of our study was to compare the T2 values of whole discs in patients with and without disc dislocation, to evaluate the possible influence of morphological findings on T2 values and to assess the interrater agreement.

Methods: Sixty-six patients were included in the study. Read More

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http://dx.doi.org/10.1016/j.mri.2019.02.002DOI Listing
February 2019
1 Read

MRI estimates of brown adipose tissue in children - Associations to adiposity, osteocalcin, and thigh muscle volume.

Magn Reson Imaging 2019 Feb 8. Epub 2019 Feb 8.

Section of Radiology, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; MRT, Entrance 24, Uppsala University Hospital, SE-751 85 Uppsala, Sweden; Antaros Medical, Mölndal, Sweden; BioVenture Hub, Pepparedsleden 1, SE-431 83 Mölndal, Sweden. Electronic address:

Context: Brown adipose tissue is of metabolic interest. The tissue is however poorly explored in children.

Methods: Sixty-three 7-year old subjects from the Swedish birth-cohort Halland Health and Growth Study were recruited. Read More

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http://dx.doi.org/10.1016/j.mri.2019.02.001DOI Listing
February 2019

Automatic classification and removal of structured physiological noise for resting state functional connectivity MRI analysis.

Magn Reson Imaging 2019 Jan 26;58:97-107. Epub 2019 Jan 26.

Multimodal Functional Imaging Lab, Department of Biomedical Engineering, McGill University, Duff Medical Building, 3775 Rue University, Montreal, QC H3A 2B4, Canada; Montreal Neurological Institute, McGill University, 3801 Rue University, Montreal, QC H3A 2B4, Canada; Department of Physics and PERFORM Centre, Concordia University, 7200 Rue Sherbrooke St. W, Montreal, QC H4B 1R6, Canada.

Resting state functional magnetic resonance imaging is used to study how brain regions are functionally connected by measuring temporal correlation of the fMRI signals, when a subject is at rest. Sparse dictionary learning is used to estimate a dictionary of resting state networks by decomposing the whole brain signals into several temporal features (atoms), each being shared by a set of voxels associated to a network. Recently, we proposed and validated a new method entitled Sparsity-based Analysis of Reliable K-hubness (SPARK), suggesting that connector hubs of brain networks participating in inter-network communication can be identified by counting the number of atoms involved in each voxel (sparse number k). Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183011
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http://dx.doi.org/10.1016/j.mri.2019.01.019DOI Listing
January 2019
1 Read

Tissue sodium concentration and sodium T mapping of the human brain at 3 T using a Variable Flip Angle method.

Magn Reson Imaging 2019 Jan 26;58:116-124. Epub 2019 Jan 26.

Department of Neurology, RWTH Aachen University, Aachen, Germany. Electronic address:

Purpose: The state-of-the-art method to quantify sodium concentrations in vivo consists in a fully relaxed 3D spin-density (SD) weighted acquisition. Nevertheless, most sodium MRI clinical studies use short-TR SD acquisitions to reduce acquisition durations. We present a clinically viable implementation of the Variable Flip Angle (VFA) method for robust and clinically viable quantification of total sodium concentration (TSC) and longitudinal relaxation rates in vivo in human brain at 3 T. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.015DOI Listing
January 2019
1 Read

Eigenvector-based SPIRiT Parallel MR Imaging Reconstruction based on ℓ pseudo-norm Joint Total Variation.

Magn Reson Imaging 2019 Jan 25;58:108-115. Epub 2019 Jan 25.

School of Microelectronics, Tianjin University, Tianjin 300072, China. Electronic address:

Parallel Magnetic Resonance (MR) imaging is a well-established acceleration technique based on the spatial sensitivities of array receivers. Eigenvector-based SPIRiT (ESPIRiT) is a new parallel MR imaging reconstruction method that combines the advantages of the SENSE and GRAPPA methods. It estimates multiple sets of the sensitivity maps from the calibration matrix that is constructed from the auto-calibration data. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.014DOI Listing
January 2019

NMR characterizing mixed wettability under intermediate-wet condition.

Magn Reson Imaging 2019 Feb 2;56:156-160. Epub 2018 Oct 2.

State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China.

Applying the concept of effective relaxivity to characterize wettability is based on the configuration of fluid distributions in porous media. However, in mixed-wet porous media with intermediate-wet patches (homogeneous wetting region), effective surface relaxivity cannot fully characterize wettability because fluid distributions are not directly corresponding to wetting patch distributions. Patches with different wettability interact with the same fluid differently, which leads to different surface relaxivity. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183033
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http://dx.doi.org/10.1016/j.mri.2018.09.023DOI Listing
February 2019
2 Reads

Design and testing of a 24-channel head coil for MR imaging at 3 T.

Magn Reson Imaging 2019 Jan 23. Epub 2019 Jan 23.

Lauterbur Imaging Research Center, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; Shenzhen Key Laboratory for MRI, Shenzhen 518055, China. Electronic address:

Purpose: To offer the new head coil option (with a lower channel count) of an RF coil array that provides comparable performance to the commercial 32-channel head coil.

Methods: The coil system comprised an upper shield (ten channels) and bottom section (fourteen channels). Signal-to-noise ratio (SNR) values for 2D unaccelerated imaging and the g-factor with an acceleration factor of 2-4 were evaluated in a phantom study. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.020DOI Listing
January 2019
4 Reads

A fiber coherence index for quality control of B-table orientation in diffusion MRI scans.

Magn Reson Imaging 2019 Jan 22;58:82-89. Epub 2019 Jan 22.

Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Electrical Engineering, Vanderbilt University, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA.

Purpose: The diffusion MRI "b-vector" table describing the diffusion sensitization direction can be flipped and permuted in dimension due to different orientation conventions used in scanners and incorrect or improperly utilized file formats. This can lead to incorrect fiber orientation estimates and subsequent tractography failure. Here, we present an automated quality control procedure to detect when the b-table is flipped and/or permuted incorrectly. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183054
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http://dx.doi.org/10.1016/j.mri.2019.01.018DOI Listing
January 2019
2 Reads

Detection of increased intracerebral lactate in a mouse model of Leigh syndrome using proton MR spectroscopy.

Magn Reson Imaging 2019 Jan 19;58:38-43. Epub 2019 Jan 19.

Department of Biomedical Imaging, National Cardiovascular and Cerebral Research Center, Suita, Osaka 565-8565, Japan; Department of Medical Physics and Engineering, Division of Health Sciences, Osaka University Graduate School of Medicine, Suita, Osaka 560-0871, Japan. Electronic address:

Purpose: To establish a brain proton magnetic resonance spectroscopy (H MRS) experimental system using a mouse model of Leigh syndrome for monitoring intracerebral lactate levels as a biomarker of mitochondrial disease progression.

Materials And Methods: Brain H MRS was performed in the Ndufs4 homozygous knockout (KO) mice, a mouse model of Leigh syndrome, and control mice on a horizontal 7.0-T magnetic resonance imaging system at age 5-9 weeks. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183052
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http://dx.doi.org/10.1016/j.mri.2019.01.010DOI Listing
January 2019
9 Reads

TherMouseDuino: An affordable Open-Source temperature control system for functional magnetic resonance imaging experimentation with mice.

Magn Reson Imaging 2019 Jan 17;58:67-75. Epub 2019 Jan 17.

Centre for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Camí de Vera s/n, 46022 Valencia, Spain. Electronic address:

Introduction: Functional magnetic resonance imaging (fMRI) is one of the most highly regarded techniques in the neuroimaging field. This technique is based on vascular responses to neuronal activation and is extensively used in clinical and animal research studies. In preclinical settings, fMRI is usually applied to anesthetized animals. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.009DOI Listing
January 2019
1 Read

Dynamics of blood brain barrier permeability and tissue microstructure following controlled cortical impact injury in rat: A dynamic contrast-enhanced magnetic resonance imaging and diffusion kurtosis imaging study.

Magn Reson Imaging 2019 Jan 17. Epub 2019 Jan 17.

Department of Radiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China; Imaging Center, Kashgar Prefecture Second People's Hospital, Kashgar 844000, Xinjiang, China. Electronic address:

Objective: The blood-brain barrier (BBB) and cerebral tissue microstructure can be impaired following traumatic brain injury (TBI). However, the spatiotemporal changes of BBB leakage and tissue microstructure are not completely understood. In this study, we evaluated the spatiotemporal changes of BBB leakage and tissue microstructure using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion kurtosis imaging (DKI) in controlled cortical impact (CCI) rats. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183062
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http://dx.doi.org/10.1016/j.mri.2019.01.017DOI Listing
January 2019
4 Reads

Age-related changes in eye morphology and aqueous humor dynamics in DBA/2J mice using contrast-enhanced ocular MRI.

Magn Reson Imaging 2019 Jan 17. Epub 2019 Jan 17.

Ocular Genetics, Unit, Smurfit Institute of Genetics, Trinity College Dublin, Lincoln Place Gate, Dublin 2, Ireland. Electronic address:

Purpose: Here, we are testing the hypothesis that dynamic contrast enhanced MRI (DCE-MRI) is a useful approach for non-invasively evaluating age-related changes in aqueous humor outflow and its contribution to elevated intraocular pressure in the DBA/2J model of pigmentary glaucoma.

Methods: A rodent-specific 7 T MRI was used to assess eye anatomy (anterior chamber (AC) and vitreous body (VB) morphology, eye size, lens size) and aqueous humor dynamics (via intravenous administration of Gd-DTPA and Gd-BOPTA contrast agents) in C57BL/6 and DBA/2J mice at 3 and 9 months of age.

Results: Gd-MRI was used to demonstrate an anterior solute pathway into the mouse AC. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.016DOI Listing
January 2019
1 Read

Sliding motion compensated low-rank plus sparse (SMC-LS) reconstruction for high spatiotemporal free-breathing liver 4D DCE-MRI.

Magn Reson Imaging 2019 Jan 15;58:56-66. Epub 2019 Jan 15.

Department of Radiology, Weill Cornell Medical College, New York, NY, United States.

Liver dynamic contrast-enhanced MRI (DCE-MRI) requires high spatiotemporal resolution and large field of view to clearly visualize all relevant enhancement phases and detect early-stage liver lesions. The low-rank plus sparse (L + S) reconstruction outperforms standard sparsity-only-based reconstruction through separation of low-rank background component (L) and sparse dynamic components (S). However, the L + S decomposition is sensitive to respiratory motion so that image quality is compromised when breathing occurs during long time data acquisition. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183044
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http://dx.doi.org/10.1016/j.mri.2019.01.012DOI Listing
January 2019
3 Reads

Space-time variant weighted regularization in compressed sensing cardiac cine MRI.

Magn Reson Imaging 2019 Jan 14;58:44-55. Epub 2019 Jan 14.

Laboratorio de Procesado de Imagen, Department of Teoría de la Señal y Comunicaciones e Ingeniería Telemática, ETSIT, Universidad de Valladolid, Campus Miguel Delibes s.n., Valladolid 47011, Spain.

Purpose: To analyze the impact on image quality and motion fidelity of a motion-weighted space-time variant regularization term in compressed sensing cardiac cine MRI.

Methods: k-t SPARSE-SENSE with temporal total variation (tTV) is used as the base reconstruction algorithm. Motion in the dynamic image is estimated by means of a robust registration technique for non-rigid motion. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183019
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http://dx.doi.org/10.1016/j.mri.2019.01.005DOI Listing
January 2019
5 Reads

Effect of spiral undersampling patterns on FISP MRF parameter maps.

Magn Reson Imaging 2019 Jan 14. Epub 2019 Jan 14.

Siemens Healthcare, Erlangen, Germany.

Purpose: Artifacts arising from undersampling are not always treatable as incoherent noise for the pattern matching process in Magnetic Resonance Fingerprinting (MRF). To estimate the effect of undersampling artifacts on MRF quantitative results, spiral sampling trajectories and their temporal variation is examined.

Methods: The effect of sampling trajectories and their variation during the MRF experiment was assessed by characterizing aliasing artifacts. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183040
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http://dx.doi.org/10.1016/j.mri.2019.01.011DOI Listing
January 2019
4 Reads

Susceptibility weighted MRI after uterine artery embolization for leiomyoma.

Magn Reson Imaging 2019 Jan 15;58:32-37. Epub 2019 Jan 15.

Department of Radiology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto 602-8566, Japan.

Purpose: To evaluate whether susceptibility-weighted MR imaging (SWI) findings are associated with tumor infarction on contrast-enhanced MRI (CE-MRI) after uterine artery embolization (UAE) for leiomyoma.

Methods: This was a single institution, retrospective study. Between February 2016 and April 2017, 27 consecutive patients underwent UAE and completed SWI and CE-MRI before and 1 week after UAE. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.013DOI Listing
January 2019

Quantification of pathophysiological alterations in venous oxygen saturation: A comparison of global MR susceptometry techniques.

Magn Reson Imaging 2019 Jan 11;58:18-23. Epub 2019 Jan 11.

Department of Physiology and Experimental Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Medical Imaging, University of Toronto, Toronto, Ontario, Canada. Electronic address:

The purpose of this study was to compare the Infinite Cylinder and Forward Field methods of quantifying global venous oxygen saturation (Y) in the superior sagittal sinus (SSS) from MRI phase data, and assess their applicability in systemic cerebrovascular disease.15 children with sickle cell disease (SCD) and 10 healthy age-matched controls were imaged on a 3.0 T MRI system. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.008DOI Listing
January 2019

The use of a binary chelate formulation: Could gadolinium based linear contrast agents be rescued by the addition of zinc selective chelates?

Magn Reson Imaging 2019 Jan 10;58:76-81. Epub 2019 Jan 10.

Magnetic Research Inc., 3152 N University Ave #50, Provo, UT 84604, United States of America. Electronic address:

Tissue and bone retention of gadolinium based contrast agents (GBCAs) has become a clinical concern because of the potential short and long term toxic effects of free gadolinium. This is a critical problem for most open-chain agents that more readily transmetallate in vivo, in comparison to macrocyclic compounds. Gadolinium diethylene tri-aminepentaacetic acid bis-glucosamide (Gd-DTPA-BIGA) is an experimental, open-chain contrast agent which has a significantly increased relaxivity coefficient in comparison to other GBCAs. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183032
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http://dx.doi.org/10.1016/j.mri.2019.01.001DOI Listing
January 2019
4 Reads
2.022 Impact Factor

MRI visualization of shiitake mycelium growing in woodchip blocks used for shiitake mushroom cultivation.

Magn Reson Imaging 2019 Jan 11;58:90-96. Epub 2019 Jan 11.

Ishikawa Agriculture and Forestry Research Center, 1-1 Mizuho, Noto-chou, Housu-gun, Ishikawa 927-0311, Japan. Electronic address:

In order to eliminate woodchip blocks where unwanted fungi have grown and select only blocks where shiitake mycelium are growing well, there is a need to develop a visualization technique for shiitake mycelium growing in woodchip blocks, and MRI is an obvious candidate technique. From the results of measurements of the woodchip bed in a small bottle (26 mm inside diameter) where shiitake mycelium was growing, the T relaxation time constant immediately after inoculation was 77.9 ± 5. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.004DOI Listing
January 2019

Using functional magnetic resonance imaging to evaluate an acute allograft rejection model in rats.

Magn Reson Imaging 2019 Jan 7;58:24-31. Epub 2019 Jan 7.

Department of Urology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China; Institute of Urology, Capital Medical University, Beijing, China. Electronic address:

Purpose: To assess the longitudinal changes of allograft pathophysiology by intravoxel incoherent motion (IVIM) and blood oxygen level-dependent (BOLD) MRI in a rat model of acute renal allograft rejection.

Materials And Methods: Acute rejection (AR) was induced by transplantation of Dark Agouti donor kidneys into Lewis recipients (n = 18). A Lewis-Lewis rat syngeneically transplanted (sTX) model served as the control (n = 6). Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.006DOI Listing
January 2019
1 Read
2.022 Impact Factor

NMR-based analysis of shear strength of weakly expansive clay in sodium chloride solution.

Magn Reson Imaging 2019 Jan 7;58:6-13. Epub 2019 Jan 7.

State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, Hubei 430071, China.

A series of direct shear and nuclear magnetic resonance (NMR) tests were performed on a compacted weakly expansive clay saturated by sodium chloride (NaCl) solutions with different concentrations to study the effect of NaCl solution on the shear strength and its mechanism. Results from the direct shear tests show that the shear strength decreases slightly with increasing the NaCl solution concentration when the concentration is less than 1.0 mol/L. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.002DOI Listing
January 2019

Slow component apparent diffusion coefficient for prostate cancer: Comparison and correlation with pharmacokinetic evaluation from dynamic contrast-enhanced MR imaging.

Magn Reson Imaging 2019 Jan 7;58:14-17. Epub 2019 Jan 7.

Department of Radiology, Osaka Medical College Hospital, Japan.

Purpose: Dynamic contrast enhancement (DCE)-MRI has high diagnostic performance of prostate cancer. However, it is preferable to avoid the use of MRI contrast media. A study reported that the diagnosability of the wash-in index of DCE-MRI was equivalent to the intravoxel incoherent motion of the diffusion weighted image. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.003DOI Listing
January 2019
1 Read

Diffusion-weighted imaging of the dentate nucleus after repeated application of gadolinium-based contrast agents in multiple sclerosis.

Magn Reson Imaging 2019 Jan 7;58:1-5. Epub 2019 Jan 7.

Department of Neurology, Universitätsmedizin Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1 - 3, 68167 Mannheim, Germany.

Objective: Over the last years several studies reported an increased signal intensity (SI) of the dentate nucleus (DN) on unenhanced T1-weighted images after repeated application of gadolinium-based contrast agents (GBCAs), suggesting gadolinium deposition. The aim of this study was to investigate with diffusion-weighted MRI possible tissue abnormalities of the DN in multiple sclerosis (MS) patients.

Material And Methods: We retrospectively identified seventeen patients with at least six contrast-enhanced MRI examinations by using the linear GBCA gadopentate dimeglumine and twenty-three patients with the exclusive use of the macrocyclic contrast agent gadoterate meglumine followed by another 3 Tesla MRI scan including unenhanced T1-weighted and diffusion-weighted images. Read More

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http://dx.doi.org/10.1016/j.mri.2019.01.007DOI Listing
January 2019
1 Read

Choroid plexus cysts analyzed using diffusion-weighted imaging with short diffusion-time.

Magn Reson Imaging 2019 Apr 31;57:323-327. Epub 2018 Dec 31.

Department of Radiology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan.

Introduction: Oscillating gradient spin-echo (OGSE) sequences can shorten diffusion times by replacing the long-lasting diffusion-sensitizing gradients used in pulsed gradient spin-echo (PGSE) methods with rapidly oscillating gradients. To obtain information regarding the internal structure of choroid plexus cysts that appear hyperintense on diffusion-weighted imaging (DWI), we investigated the apparent diffusion coefficient (ADC) values acquired with a shorter diffusion time using an OGSE sequence.

Material And Methods: Twenty-seven patients with choroid plexus cysts were scanned using a 3 T magnetic resonance scanner. Read More

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http://dx.doi.org/10.1016/j.mri.2018.12.010DOI Listing
April 2019
2.022 Impact Factor

Diffusion kurtosis imaging of endometrial carcinoma: Correlation with histopathological findings.

Magn Reson Imaging 2019 Apr 30;57:337-346. Epub 2018 Dec 30.

Department of Human Pathology, Tokyo Medical and Dental University, Tokyo, Japan.

Purpose: In this study, we aimed to determine the usefulness of diffusion kurtosis imaging (DKI) as a noninvasive method for the evaluation of tumor invasion depth, histological grade, and lymph node metastasis in patients with endometrial carcinoma (EMC).

Materials And Methods: Our institutional review board approved this retrospective study and waived informed consent. In total, 24 patients suspected of having EMC were examined by a 1. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183056
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http://dx.doi.org/10.1016/j.mri.2018.12.009DOI Listing
April 2019
3 Reads

Incorporating reference guided priors into calibrationless parallel imaging reconstruction.

Magn Reson Imaging 2019 Apr 28;57:347-358. Epub 2018 Dec 28.

Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.

Purpose: To propose and evaluate a new calibrationless parallel imaging method aimed at further improving the reconstruction accuracy of the accelerated multi-channel MR images.

Method: We introduce a new calibrationless parallel imaging method. On top of exploiting joint sparsity cross channels of the target image to be reconstructed, it incorporates similar priors on the grey-level intensity and edge orientation, which both come from a high-spatial resolution reference image that can be easily obtained in many clinical MRI scenarios. Read More

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http://dx.doi.org/10.1016/j.mri.2018.12.006DOI Listing
April 2019
2.022 Impact Factor

Water mobility spectral imaging of the spinal cord: Parametrization of model-free Laplace MRI.

Magn Reson Imaging 2019 Feb 22;56:187-193. Epub 2018 Dec 22.

Section on Quantitative Imaging and Tissue Sciences, NICHD, National Institutes of Health, Bethesda, MD 20892, USA.

Diffusion magnetic resonance imaging (dMRI) of biological systems most often results in non-monoexponential signal, due to their complexity and heterogeneity. One approach to interpreting dMRI data without imposing tissue microstructural models is to fit the signal to a multiexponential function, which is sometimes referred to as an inverse Laplace transformation, and to display the coefficients as a distribution of the diffusivities, or water mobility spectra. Until recently, this method has not been used in a voxelwise manner, mainly because of heavy data requirements. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183046
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http://dx.doi.org/10.1016/j.mri.2018.12.001DOI Listing
February 2019
3 Reads

Quantification of morphometry and intensity features of intracranial arteries from 3D TOF MRA using the intracranial artery feature extraction (iCafe): A reproducibility study.

Magn Reson Imaging 2019 Apr 20;57:293-302. Epub 2018 Dec 20.

Department of Radiology, University of Washington, Seattle, WA 98195, USA. Electronic address:

Background: Accurate and reliable vascular features extracted from 3D time-of-flight (TOF) magnetic resonance angiography (MRA) can help evaluate cerebral vascular diseases and conditions. The goal of this study was to evaluate the reproducibility of an intracranial artery feature extraction (iCafe) algorithm for quantitative analysis of intracranial arteries from TOF MRA.

Methods: Twenty-four patients with known intracranial artery stenosis were recruited and underwent two separate MRA scans within 2 weeks of each other. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183053
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http://dx.doi.org/10.1016/j.mri.2018.12.007DOI Listing
April 2019
8 Reads

Diagnostic efficacy of MRI for pre-operative assessment of ovarian malignancy in endometrial carcinoma: A decision tree analysis.

Magn Reson Imaging 2019 Apr 21;57:285-292. Epub 2018 Dec 21.

Department of Gynecology, The Central Hospital of Karamay, Xinjiang, Uyghur Autonomous Region, China. Electronic address:

Aim: Accurate preoperative assessment of ovarian malignancy in endometrial carcinoma helps in determining the decision to preserve the ovaries in individualized treatment. This study adopted decision tree method to evaluate the diagnostic efficiency of pelvic MRI and clinical data of patients for preoperative identification of endometrial carcinoma-combined ovarian malignancy (EC-OM).

Material And Methods: This retrospective study included a total of 801 patients, and postoperative pathological examinations identified 58 EC-OM group and 743 endometrial carcinoma cases without ovarian malignancy (EC group). Read More

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http://dx.doi.org/10.1016/j.mri.2018.12.008DOI Listing
April 2019
4 Reads

Is it worth to perform preoperative MRI for breast cancer after mammography, tomosynthesis and ultrasound?

Magn Reson Imaging 2019 Apr 20;57:317-322. Epub 2018 Dec 20.

Department of Radiology, Clínica Universidad de Navarra, Pamplona, Navarra, Spain. Electronic address:

Background: The use of preoperative breast MRI remains controversial despite being the most sensitive technique for the detection of breast malignancies.

Purpose: To evaluate the benefit of preoperative breast MRI after performing the three conventional techniques (DM, US, DBT). To analyze the influence of breast density in the sensitivity of the different imaging techniques. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183050
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http://dx.doi.org/10.1016/j.mri.2018.12.005DOI Listing
April 2019
2 Reads
2.022 Impact Factor

Combination of free-breathing radial 3D fat-suppressed T1-weighted gradient-echo sequence with diffusion weighted images: Potential for differentiating malignant from benign peripheral solid pulmonary masses.

Magn Reson Imaging 2019 Apr 14;57:271-276. Epub 2018 Dec 14.

Department of Radiology, The affiliated hospital of Shaanxi university of Chinese medicine, Xian Yang, China. Electronic address:

Objectives: High resolution CT is the most commonly used radiological method for differentiating benign from malignant peripheral solid pulmonary masses, however, some of them are not easily diagnosed by morphology alone. Furthermore, due to the radiation dose, it is unsuitable for patients with disorders requiring repeated examinations over prolonged periods. The aims of this study were to evaluate whether a combination of diffusion-weighted images (DWI) and free-breathing radial 3D fat-suppressed T1-weighted gradient echo (radial volumetric interpolated breath-hold examination, radial VIBE) sequence can enable discrimination between benign from malignant peripheral solid pulmonary masses. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183063
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http://dx.doi.org/10.1016/j.mri.2018.12.004DOI Listing
April 2019
4 Reads
2.022 Impact Factor

Novel distortion correction method for diffusion-weighted imaging based on non-rigid image registration between low b value image and anatomical image.

Magn Reson Imaging 2019 Apr 10;57:277-284. Epub 2018 Dec 10.

Division of Health Sciences, Graduate School of Medical Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, 920-0942, Japan. Electronic address:

Purpose: This study aimed to develop a novel technique for retrospective distortion correction based on non-rigid image registration in magnetic resonance diffusion image.

Methods: A 3.0 T MRI scanner with an 18-channel dedicated breast coil and the outer shell of the original breast phantom, which provided images with non-uniform fat-suppression based on clinical data were used. Read More

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http://dx.doi.org/10.1016/j.mri.2018.12.002DOI Listing

Diffusion MRI detects longitudinal white matter changes in the 3xTg-AD mouse model of Alzheimer's disease.

Magn Reson Imaging 2019 Apr 11;57:235-242. Epub 2018 Dec 11.

Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA; Center for Biomedical Imaging, Medical University of South Carolina, Charleston, SC, USA; Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA.

The sensitivity of multiple diffusion MRI (dMRI) parameters to longitudinal changes in white matter microstructure was investigated for the 3xTg-AD transgenic mouse model of Alzheimer's disease, which manifests both amyloid beta plaques and neurofibrillary tangles. By employing a specific dMRI method known as diffusional kurtosis imaging, eight different diffusion parameters were quantified to characterize distinct aspects of water diffusion. Four female 3xTg-AD mice were imaged at five time points, ranging from 4. Read More

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http://dx.doi.org/10.1016/j.mri.2018.12.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6331227PMC

Two-dimensional nuclear magnetic resonance method for wettability determination of tight sand.

Magn Reson Imaging 2019 Feb 5;56:144-150. Epub 2018 Dec 5.

State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China.

The wettability of reservoir rocks is important for oil recovery and reserve calculations. However, current methods for evaluating the wettability of rocks are time-consuming and expensive. Previous work has shown that low-field nuclear magnetic resonance (NMR) is a potentially useful and non-invasive technique for rock wettability determination. Read More

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http://dx.doi.org/10.1016/j.mri.2018.09.020DOI Listing
February 2019
1 Read

Challenges in diffusion MRI tractography - Lessons learned from international benchmark competitions.

Magn Reson Imaging 2019 Apr 29;57:194-209. Epub 2018 Nov 29.

Sherbrooke Connectivity Imaging Lab (SCIL), Computer Science Department, Université de Sherbrooke, Québec, Canada.

Diffusion MRI (dMRI) fiber tractography has become a pillar of the neuroimaging community due to its ability to noninvasively map the structural connectivity of the brain. Despite widespread use in clinical and research domains, these methods suffer from several potential drawbacks or limitations. Thus, validating the accuracy and reproducibility of techniques is critical for sound scientific conclusions and effective clinical outcomes. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6331218PMC
April 2019
7 Reads

WITHDRAWN: NMR characterizing mixed wettability under intermediate-wet condition.

Magn Reson Imaging 2018 Nov 29. Epub 2018 Nov 29.

State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China.

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http://dx.doi.org/10.1016/j.mri.2018.09.030DOI Listing
November 2018
3 Reads

Denoising of MR images using Kolmogorov-Smirnov distance in a Non Local framework.

Magn Reson Imaging 2019 Apr 2;57:176-193. Epub 2018 Dec 2.

Dipartimento di Ingegneria, Università degli Studi di Napoli Parthenope, Napoli, Italy. Electronic address:

Data coming from any acquisition system, such as Magnetic Resonance Imaging ones, are affected by noise. Although modern high field scanners can reach high Signal to Noise Ratios, in some circumstances, for example in case of very weak signals due to a specific acquisition sequence, noise becomes a critical issue that has to be properly handled. In the last years methods based on the so called Non Local Mean have proven to be very effective in denoising tasks. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.022DOI Listing
April 2019
9 Reads

Robustly reconstructing magnetic resonance images via structure decomposition.

Magn Reson Imaging 2019 Apr 28;57:165-175. Epub 2018 Nov 28.

College of Electrical Engineering and Information Technology, Sichuan University, No.24 South Section 1, Yihuan Road, Chengdu, China.

In magnetic resonance (MR) imaging, for highly under-sampled k-space data, it is typically difficult to reconstruct images and preserve their original texture simultaneously. The high-degree total variation (HDTV) regularization handles staircase effects but still blurs textures. On the other hand, the non-local TV (NLTV) regularization can preserve textures, but will introduce additional artifacts for highly-noised images. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.020DOI Listing

Dual-contrast pCASL using simultaneous gradient-echo/spin-echo multiband EPI.

Magn Reson Imaging 2019 Apr 27;57:359-367. Epub 2018 Nov 27.

Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany; Department of Radiology, German Cancer Research Center, Heidelberg, Germany. Electronic address:

A 2D gradient-echo EPI is commonly employed for arterial spin labeling (ASL) readout to achieve fast whole brain coverage measurements. However, such a readout suffers from susceptibility artifacts induced by magnetic field inhomogeneities. To reduce these susceptibility effects, single-shot spin-echo EPI was proposed to be used for acquisitions in continuous ASL (CASL). Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.018DOI Listing
April 2019
1 Read

7-Tesla MRI of the brain in a research subject with bilateral, total knee replacement implants: Case report and proposed safety guidelines.

Magn Reson Imaging 2019 Apr 27;57:313-316. Epub 2018 Nov 27.

Department of Radiology, Keck School of Medicine of University of Southern California, 1975 Zonal Ave, Los Angeles, CA 90033, United States of America.

Recently, the first 7-T MR system was approved for clinical use in the United States. Unfortunately, relatively few metallic implants have undergone testing to determine if they are acceptable or pose hazards to research subjects and patients at this ultra-high-field strength. Therefore, in lieu of not performing a research or clinical MRI exam at 7-T, the supervising physician may make a decision to scan the individual with an untested metallic implant based on an analysis of the risks vs. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.016DOI Listing
April 2019
9 Reads

Comparison of NODDI and spherical mean signal for measuring intra-neurite volume fraction.

Magn Reson Imaging 2019 Apr 26;57:151-155. Epub 2018 Nov 26.

Department of Radiology, Nemours - Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA.

Purpose: Neurite orientation dispersion and density imaging (NODDI) is a clinically feasible approach to measure intra-neurite volume fraction (f). However, the sophisticated fitting procedure takes several hours. And the NODDI model relied on several questionable assumptions. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S0730725X183046
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http://dx.doi.org/10.1016/j.mri.2018.11.021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6331250PMC
April 2019
4 Reads

High temperature/pressure MAS-NMR for the study of dynamic processes in mixed phase systems.

Magn Reson Imaging 2019 Feb 25;56:37-44. Epub 2018 Oct 25.

Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99354, United States. Electronic address:

A new MAS-NMR rotor (the WHiMS rotor) has been developed which can reach pressures of 400 bar at 20 °C or 225 bar at 250 °C. These rotors are ideal for mixed phase systems such as a reaction using a solid catalyst with a liquid/supercritical solvent topped with high pressure gas in the head space. After solid and liquid portions of the sample are loaded, the rotor is capped with an o-ring equipped polymer bushing that snaps into a mating groove in the rotor. Read More

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http://dx.doi.org/10.1016/j.mri.2018.09.026DOI Listing
February 2019

Magnetic resonance imaging in the presence of projectiles and projectile fragments: Artefacts, image quality, rotation and movement.

Magn Reson Imaging 2019 Apr 22;57:143-150. Epub 2018 Nov 22.

Department of Neurosurgery, German Armed Forces Hospital of Ulm, Germany.

Background And Purpose: Gunshot injuries have been considered a contraindication for MRI because of the risk of secondary dislodgement of retained metallic foreign bodies. The objective of our study was to provide a systematic overview of the behaviour of projectiles and fragments in order to aid decision-making regarding the use of MRI in clinical practice.

Materials And Methods: Ferromagnetic (n = 2) and non-ferromagnetic (n = 5) projectiles and fragments that were lodged in soft tissue (porcine masseter muscles) were examined using standard protocols at 1, 1. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.019DOI Listing
April 2019
1 Read

Isotropically weighted intravoxel incoherent motion brain imaging at 7T.

Magn Reson Imaging 2019 Apr 23;57:124-132. Epub 2018 Nov 23.

Bernstein Center for Computational Neuroscience, Berlin, Germany; Department of Physics, Humboldt University, Berlin, Germany.

Perfusion magnetic resonance imaging (MRI) is a promising non-invasive technique providing insights regarding the brain's microvascular architecture in vivo. The scalar perfusion metrics can be used for quantitative diagnostics of various brain abnormalities, in particular, in the stroke cases and tumours. However, conventional MRI-based perfusion approaches such as dynamic contrast-enhanced perfusion imaging or arterial spin labelling have a few weaknesses, for instance, contrast agent deposition, low signal-to-noise ratio, limited temporal and spatial resolution, and specific absorption rate constraints. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.007DOI Listing
April 2019
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Influence of excess ligand on Nephrogenic Systemic Fibrosis associated with nonionic, linear gadolinium-based contrast agents.

Magn Reson Imaging 2018 Nov 21. Epub 2018 Nov 21.

Department of Radiology, Hospital Garcia de Orta, EPE, Almada, Portugal.

Background: The molecular structure, charge, thermodynamic and kinetic stability are approximately the same for gadodiamide and gadoversetamide, the main substantive difference is that gadodiamide is manufactured with 5% free ligand to form Omniscan® and gadoversetamide with 10% free ligand to form OptiMARK®.

Purpose: To determine the relative risk of Nephrogenic Systemic Fibrosis (NSF) between gadodiamide (Omniscan®) and gadoversetamide (OptiMARK®) and to explore the potential contribution of the amount of excess ligand added to their commercial formulations.

Materials And Methods: In this retrospective observational study, the number of doses and NSF cases associated with these agents were calculated based on two different approaches: the number of doses was determined based on pharmaceutical companies' information, and the number of unconfounded NSF cases was obtained from the previously published literature based on a legal database. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.015DOI Listing
November 2018
2.022 Impact Factor

Sampling arterial input function (AIF) from peripheral arteries: Comparison of a temporospatial-feature based method against conventional manual method.

Magn Reson Imaging 2019 Apr 22;57:118-123. Epub 2018 Nov 22.

Department of Radiology and Imaging Sciences, University of Utah, 729 Arapeen Drive, Salt Lake City, UT, United States. Electronic address:

It is often difficult to accurately localize small arteries in images of peripheral organs, and even more so with vascular abnormality vasculatures, including collateral arteries, in peripheral artery disease (PAD). This poses a challenge for manually sampling arterial input function (AIF) in quantifying dynamic contrast-enhanced (DCE) MRI data of peripheral organs. In this study, we designed a multi-step screening approach that utilizes both the temporal and spatial information of the dynamic images, and is presumably suitable for localizing small and unpredictable peripheral arteries. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6331273PMC

Characterization and correlation of signal drift in diffusion weighted MRI.

Magn Reson Imaging 2019 Apr 22;57:133-142. Epub 2018 Nov 22.

Computer Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Electrical Engineering, Vanderbilt University, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA.

Diffusion weighted MRI (DWMRI) and the myriad of analysis approaches (from tensors to spherical harmonics and brain tractography to body multi-compartment models) depend on accurate quantification of the apparent diffusion coefficient (ADC). Signal drift during imaging (e.g. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.009DOI Listing

Comparison of dynamic contrast-enhanced magnetic resonance imaging and contrast-enhanced ultrasound for evaluation of the effects of sorafenib in a rat model of hepatocellular carcinoma.

Magn Reson Imaging 2019 Apr 19;57:156-164. Epub 2018 Nov 19.

Department of Interventional Radiology at The University of Texas M.D. Anderson Cancer Center, Houston, TX, United States of America. Electronic address:

Objectives: To compare the accuracy of contrast-enhanced ultrasound (CEUS) and Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) for the assessment of changes in tissue vascularization as result of sorafenib treatment in a rat model of hepatocellular carcinoma (HCC).

Methods: Male Buffalo rats with orthotopic liver tumors treated daily with 7.5 mg/kg sorafenib via oral gavage for 2 weeks (n = 9) were subject to DCE-MRI and CEUS 2 weeks after tumor implantation - right before treatment initiation - and also after treatment completion - right before tumor harvest. Read More

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http://dx.doi.org/10.1016/j.mri.2018.11.012DOI Listing
April 2019
8 Reads