scholarly journals Imaging and Gross Pathological Appearance of Changes in the Parasagittal Grooves of Thoroughbred Racehorses

Animals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3366
Author(s):  
Georgina C. A. Johnston ◽  
Benjamin J. Ahern ◽  
Chiara Palmieri ◽  
Alex C. Young
Keyword(s):  
Cartilage Defects ◽  
Resonance Imaging ◽  
Limited Evidence ◽  
Advanced Imaging ◽  
Low Field ◽  
Thoroughbred Racehorses ◽  
Microdamage Accumulation ◽  
Pathological Appearance ◽  
Magnetic Resonance Imaging Mri ◽  
Adaptive Modelling

(1) Background: Parasagittal groove (PSG) changes are often present on advanced imaging of racing Thoroughbred fetlocks and have been suggested to indicate increased fracture risk. Currently, there is limited evidence differentiating the imaging appearance of prodromal changes in horses at risk of fracture from horses with normal adaptive modelling in response to galloping. This study aims to investigate imaging and gross PSG findings in racing Thoroughbreds and the comparative utility of different imaging modalities to detect PSG changes. (2) Methods: Cadaver limbs were collected from twenty deceased racing/training Thoroughbreds. All fetlocks of each horse were examined with radiography, low-field magnetic resonance imaging (MRI), computed tomography (CT), contrast arthrography and gross pathology. (3) Results: Horses with fetlock fracture were more likely to have lateromedial PSG sclerosis asymmetry and/or lateral PSG lysis. PSG lysis was not readily detected using MRI. PSG subchondral bone defects were difficult to differentiate from cartilage defects on MRI and were not associated with fractures. The clinical relevance of PSG STIR hyperintensity remains unclear. Overall, radiography was poor for detecting PSG changes. (4) Conclusions: Some PSG changes in Thoroughbred racehorses are common; however, certain findings are more prevalent in horses with fractures, possibly indicating microdamage accumulation. Bilateral advanced imaging is recommended in racehorses with suspected fetlock pathology.

Improved Contrast in Ultra-Low-Field MRI with Time-Dependent Bipolar Prepolarizing Fields: Theory and NMR Demonstrations

2013 ◽  
Vol 20 (3) ◽  
pp. 327-336 ◽  
Author(s):  
Jaakko O. Nieminen ◽  
Jens Voigt ◽  
Stefan Hartwig ◽  
Hans Jürgen Scheer ◽  
Martin Burghoff ◽  
...  
Keyword(s):  
Field Strength ◽  
Time Course ◽  
Signal Strength ◽  
Relaxation Rates ◽  
Resonance Imaging ◽  
New Approach ◽  
Spin Lattice ◽  
Low Field ◽  
Low Field Mri ◽  
Magnetic Resonance Imaging Mri

Abstract The spin-lattice (T1) relaxation rates of materials depend on the strength of the external magnetic field in which the relaxation occurs. This T1 dispersion has been suggested to offer a means to discriminate between healthy and cancerous tissue by performing magnetic resonance imaging (MRI) at low magnetic fields. In prepolarized ultra-low-field (ULF) MRI, spin precession is detected in fields of the order of 10-100 μT. To increase the signal strength, the sample is first magnetized with a relatively strong polarizing field. Typically, the polarizing field is kept constant during the polarization period. However, in ULF MRI, the polarizing-field strength can be easily varied to produce a desired time course. This paper describes how a novel variation of the polarizing-field strength and duration can optimize the contrast between two types of tissue having different T1 relaxation dispersions. In addition, NMR experiments showing that the principle works in practice are presented. The described procedure may become a key component for a promising new approach of MRI at ultra-low fields

scholarly journals Acute Mesenteric Vein Thrombosis in a Pregnant Patient at 10 Weeks Gestation: A Case Report

Diagnostics ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1348
Author(s):  
Ying-Ying Chen ◽  
Sheng-Mao Wu ◽  
Russell Oliver Kosik ◽  
Yi-Chien Hsieh ◽  
Tzu-I Wu ◽  
...  
Keyword(s):  
Acute Abdominal Pain ◽  
Clinical Manifestations ◽  
Pregnant Patient ◽  
Resonance Imaging ◽  
Advanced Imaging ◽  
Mesenteric Vein Thrombosis ◽  
Mesenteric Vein ◽  
Vein Thrombosis ◽  
Management Perspective ◽  
Magnetic Resonance Imaging Mri

Acute abdominal pain during pregnancy is challenging, both from a diagnostic and management perspective. A non-localized, persistent pain out of proportion to physical examination is a sign that advanced imaging may be necessary. Mesenteric venous thrombosis in a pregnant patient is extremely rare, but if diagnosis is delayed, can be potentially fatal to both the mother and the fetus. We present here a pregnant patient in the tenth week of gestation with classic clinical manifestations of mesenteric vein thrombosis and the corresponding findings on magnetic resonance imaging (MRI) and computed tomography (CT).

scholarly journals Effectiveness of low-field magnetic resonance imaging in diagnosing brachial plexus tumours in dogs – short communication

2015 ◽  
Vol 59 (2) ◽  
pp. 317-319
Author(s):  
Zbigniew Adamiak ◽  
Yauheni Zhalniarovich ◽  
Paulina Przyborowska ◽  
Joanna Głodek ◽  
Adam Przeworski
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Brachial Plexus ◽  
Resonance Imaging ◽  
Gadolinium Contrast ◽  
Gadolinium Contrast Agent ◽  
Low Field ◽  
Mri Sequences ◽  
Magnetic Resonance Imaging Mri ◽  
Brachial Plexus Tumours

AbstractThe aim of the study was to identify magnetic resonance imaging (MRI) sequences that contribute to a quick and reliable diagnosis of brachial plexus tumours in dogs. The tumours were successfully diagnosed in 6 dogs by the MRI with the use of SE, FSE, STIR, Turbo 3 D, 3D HYCE, and GE sequences and the gadolinium contrast agent

Detection of Erosions in Sacroiliac Joints of Patients with Axial Spondyloarthritis Using the Magnetic Resonance Imaging Volumetric Interpolated Breath-hold Examination

2019 ◽  
Vol 46 (11) ◽  
pp. 1445-1449 ◽  
Author(s):  
Xenofon Baraliakos ◽  
Florian Hoffmann ◽  
Xiaohu Deng ◽  
Yan-Yan Wang ◽  
Feng Huang ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Structural Changes ◽  
Axial Spondyloarthritis ◽  
Linear Regression Analysis ◽  
Cartilage Defects ◽  
Breath Hold ◽  
Resonance Imaging ◽  
Sacroiliac Joints ◽  
Magnetic Resonance Imaging Mri

Objective.The volumetric interpolated breath-hold examination (VIBE) magnetic resonance imaging (MRI) technique can visualize erosive cartilage defects in peripheral joints. We evaluated the ability of VIBE to detect erosions in sacroiliac joints (SIJ) of patients with axial spondyloarthritis (axSpA) compared to the established T1-weighted MRI sequence and computed tomography (CT).Methods.MRI (T1-weighted and VIBE) and CT scans of SIJ of 109 patients with axSpA were evaluated by 2 blinded readers based on SIJ quadrants (SQ). Erosions were defined according to Assessment of Spondyloarthritis international Society (ASAS) definitions. Scores were recorded if readers were in agreement.Results.Erosions were less frequently detected by CT (153 SQ) than by T1-weighted MRI (182 SQ; p = 0.008) and VIBE-MRI (199 SQ; p < 0.001 vs CT and p = 0.031 vs T1-weighted MRI). Taking CT as the gold standard, the sensitivity of VIBE-MRI (71.2%) was higher than that for T1-weighted MRI (63.4%), with similar specificity (87.3% vs 88%, respectively). In linear regression analysis, younger age was significantly associated with occurrence of erosions independently in VIBE-MRI (β = 0.384, p < 0.001) and T1-weighted MRI (β = 0.369, p < 0.001) compared to CT.Conclusion.The VIBE-MRI sequence was more sensitive than T1-weighted MRI in identifying erosive damage in the SIJ, especially in younger patients. This might be due to the ability of VIBE-MRI to identify structural changes in the cartilage that have not yet extended to the underlying bone, where CT seems to be superior.

Monitoring a typical fermentation process of natto by low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) techniques

2016 ◽  
Vol 8 (39) ◽  
pp. 7135-7140 ◽  
Author(s):  
Jing Wu ◽  
Yanru Li ◽  
Xingsheng Gao
Keyword(s):  
Magnetic Resonance Imaging ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Fermentation Process ◽  
Resonance Imaging ◽  
Low Field ◽  
Magnetic Resonance Imaging Mri ◽  
Lf Nmr ◽  
Nuclear Magnetic

Unique insights into the monitoring of a typical fermentation process of natto based on low field nuclear magnetic resonance (LF-NMR) associated with magnetic resonance imaging (MRI).

scholarly journals The Role of Advanced MRI in the Development of Treat-to-Target Therapeutic Strategies, Patient Stratification and Phenotyping in Rheumatoid Arthritis

2019 ◽  
Author(s):  
Ali Mobasheri ◽  
Mark Hinton ◽  
Olga Kubassova
Keyword(s):  
Rheumatoid Arthritis ◽  
Bone Marrow Edema ◽  
Objective Assessment ◽  
Treat To Target ◽  
Resonance Imaging ◽  
Advanced Imaging ◽  
Dce Mri ◽  
Contrast Enhanced ◽  
Magnetic Resonance Imaging Mri

Abstract In this commentary we discuss the potential of advanced imaging, particularly Dynamic Contrast Enhanced (DCE) magnetic resonance imaging (MRI) for the objective assessment of disease progression in rheumatoid arthritis (RA). We emphasise the potential DCE-MRI in advancing the field and exploring new areas of research and development in RA. We believe that different grades of bone marrow edema (BME) and synovitis in RA can be examined and monitored in a more sensitive manner with DCE-MRI. Future treatments for RA will be significantly improved by enhanced imaging of BMEs and synovitis. DCE-MRI will also facilitate enhanced stratification and phenotyping of patients enrolled in clinical trials.

Evaluation of Magnetic Resonance Imaging Responsiveness in Active Psoriatic Arthritis at Multiple Timepoints during the First 12 Weeks of Antitumor Necrosis Factor Therapy

2015 ◽  
Vol 43 (1) ◽  
pp. 75-80 ◽  
Author(s):  
Marie Feletar ◽  
Stephen Hall ◽  
Paul Bird
Keyword(s):  
Magnetic Resonance Imaging ◽  
Psoriatic Arthritis ◽  
Magnetic Resonance ◽  
High Field ◽  
Early Response ◽  
Resonance Imaging ◽  
Low Field ◽  
Low Field Mri ◽  
Magnetic Resonance Imaging Mri ◽  
Necrosis Factor

Objective.To assess the responsiveness of high- and low-field extremity magnetic resonance imaging (MRI) variables at multiple timepoints in the first 12 weeks post-antitumor necrosis factor (anti-TNF) therapy initiation in patients with psoriatic arthritis (PsA) and active dactylitis.Methods.Twelve patients with active PsA and clinical evidence of dactylitis involving at least 1 digit were recruited. Patients underwent sequential high-field conventional (1.5 Tesla) and extremity low-field MRI (0.2 Tesla) of the affected hand or foot, pre- and postgadolinium at baseline (pre-TNF), 2 weeks (post-TNF), 6 weeks, and 12 weeks. A blinded observer scored all images on 2 occasions using the PsA MRI scoring system.Results.Eleven patients completed the study, but only 6 patients completed all high-field and low-field MRI assessments. MRI scores demonstrated rapid response to TNF inhibition with score reduction in tenosynovitis, synovitis, and osteitis at 2 weeks. Intraobserver reliability was good to excellent for all variables. High-field MRI demonstrated greater sensitivity to tenosynovitis, synovitis, and osteitis and greater responsiveness to change posttreatment. Treatment responses were maintained to 12 weeks.Conclusion.This study demonstrates the use of MRI in detecting early response to biologic therapy. MRI variables of tenosynovitis, synovitis, and osteitis demonstrated responsiveness posttherapy with high-field scores more responsive to change than low-field scores.

scholarly journals B0-Shimming Methodology for Affordable and Compact Low-Field Magnetic Resonance Imaging Magnets

2021 ◽  
Vol 9 ◽  
Author(s):  
Konstantin Wenzel ◽  
Hazem Alhamwey ◽  
Tom O’Reilly ◽  
Layla Tabea Riemann ◽  
Berk Silemek ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Field ◽  
Magnetic Resonance ◽  
Point Of Care ◽  
Low Cost ◽  
Field Measurements ◽  
Target Volume ◽  
Resonance Imaging ◽  
Low Field ◽  
Magnetic Resonance Imaging Mri

Low-field (B0 &lt; 0.2 T) magnetic resonance imaging (MRI) is emerging as a low cost, point-of-care alternative to provide access to diagnostic imaging technology even in resource scarce environments. MRI magnets can be constructed based on permanent neodymium-iron-boron (NdFeB) magnets in discretized arrangements, leading to substantially lower mass and costs. A challenge with these designs is, however, a good B0 field homogeneity, which is needed to produce high quality images free of distortions. In this work, we describe an iterative approach to build a low-field MR magnet based on a B0-shimming methodology using genetic algorithms. The methodology is tested by constructing a small bore (inner bore diameter = 130 mm) desktop MR magnet (&lt;15 kg) at a field strength of B0 = 0.1 T and a target volume of 4 cm in diameter. The configuration consists of a base magnet and shim inserts, which can be placed iteratively without modifying the base magnet assembly and without changing the inner dimensions of the bore or the outer dimensions of the MR magnet. Applying the shims, B0 field inhomogeneity could be reduced by a factor 8 from 5,448 to 682 ppm in the target central slice of the magnet. Further improvements of these results can be achieved in a second or third iteration, using more sensitive magnetic field probes (e.g., nuclear magnetic resonance based magnetic field measurements). The presented methodology is scalable to bigger magnet designs. The MR magnet can be reproduced with off-the-shelf components and a 3D printer and no special tools are needed for construction. All design files and code to reproduce the results will be made available as open source hardware.

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