keyword
MENU ▼
Read by QxMD icon Read
search

2d echo

keyword
https://www.readbyqxmd.com/read/28210715/feasibility-and-reproducibility-of-two-dimensional-wall-motion-tracking-wmt-in-fetal-echocardiography
#1
Christian Enzensberger, Friederike Achterberg, Jan Degenhardt, Aline Wolter, Oliver Graupner, Johannes Herrmann, Roland Axt-Fliedner
Objective The primary objective of this study was to determine the feasibility and reproducibility of 2-dimensional speckle tracking imaging based on the wall motion tracking (WMT) technique in fetal echocardiography. The secondary objective was to compare left and right ventricular global and segmental longitudinal peak strain values. Methods A prospective cross-sectional study was performed. Global and segmental longitudinal peak strain values of the left ventricle (LV) and right ventricle (RV) were assessed prospectively...
February 2017: Ultrasound International Open
https://www.readbyqxmd.com/read/28207657/3-tesla-kinematic-mri-of-the-cervical-spine-for-evaluation-of-adjacent-level-disease-after-monosegmental-anterior-cervical-discectomy-and-arthroplasty-results-of-2-year-follow-up
#2
Steffen K Fleck, Soenke Langner, Christian Rosenstengel, Rebecca Kessler, Marc Matthes, Jan-Uwe Müller, Inga Langner, Sascha Marx, Henry W S Schroeder
STUDY DESIGN: We prospectively evaluated adjacent disc levels after anterior cervical discectomy and arthroplasty (ACDA) using kinematic magnetic resonance imaging (MRI) and plain functional radiographs. OBJECTIVE: ACDA is an established treatment for degenerative cervical disc disease. The objective of this study was to evaluate the use of kinematic MRI for assessing the range of motion (ROM) before and after ACDA compared with plain functional radiographs and to evaluate adjacent degenerative disc disease (aDDD) at mid-term follow-up...
February 15, 2017: Spine
https://www.readbyqxmd.com/read/28197872/mr-arthrography-of-the-shoulder-evaluation-of-isotropic-3d-intermediate-weighted-fse-and-hybrid-gre-t1-weighted-sequences
#3
Giovanni Foti, Paolo Avanzi, William Mantovani, Flavia Dal Corso, Emanuele Demozzi, Claudio Zorzi, Giovanni Carbognin
PURPOSE: To compare the diagnostic accuracy of three-dimensional (3D) fast spin echo (FSE) intermediate-weighed (IW-3D) and 3D hybrid double-echo steady-state T1-weighted sequences (Hy-3D) and two-dimensional (FSE) images (2D) at shoulder MR arthrography (MRA). MATERIALS AND METHODS: Institutional review board approval was obtained and informed consent was waived for this retrospective study. From September 2011 to October 2014, 102 patients who had undergone 1...
February 15, 2017: La Radiologia Medica
https://www.readbyqxmd.com/read/28196133/b1-insensitive-t2-mapping-of-healthy-thigh-muscles-using-a-t2-prepared-3d-tse-sequence
#4
Elisabeth Klupp, Dominik Weidlich, Sarah Schlaeger, Thomas Baum, Barbara Cervantes, Marcus Deschauer, Hendrik Kooijman, Ernst J Rummeny, Claus Zimmer, Jan S Kirschke, Dimitrios C Karampinos
PURPOSE: To propose a T2-prepared 3D turbo spin echo (T2prep 3D TSE) sequence for B1-insensitive skeletal muscle T2 mapping and compare its performance with 2D and 3D multi-echo spin echo (MESE) for T2 mapping in thigh muscles of healthy subjects. METHODS: The performance of 2D MESE, 3D MESE and the proposed T2prep 3D TSE in the presence of transmit B1 and B0 inhomogeneities was first simulated. The thigh muscles of ten young and healthy subjects were then scanned on a 3 T system and T2 mapping was performed using the three sequences...
2017: PloS One
https://www.readbyqxmd.com/read/28194611/using-three-dimensional-echocardiography-to-guide-left-ventricle-lead-position-in-cardiac-resynchronization-therapy-does-it-make-any-difference
#5
Haitham A Badran, John Z Kamel, Tarek R Mohamed, Mohamed A Abdelhamid
BACKGROUND: Cardiac resynchronization therapy (CRT) is an effective treatment for patients with advanced heart failure. Nearly 30% of candidates are inadequate responders. Proper patient selection, left ventricle (LV) lead placement optimization, and optimization of the programming of the CRT device are important approaches to improve outcome of CRT. We examined the role of three-dimensional (3D) echocardiography in determining the optimal LV lead position as a method of optimizing CRT response...
February 13, 2017: Journal of Interventional Cardiac Electrophysiology: An International Journal of Arrhythmias and Pacing
https://www.readbyqxmd.com/read/28187250/phase-imaging-with-multiple-phase-cycled-balanced-steady-state-free-precession-at-9-4%C3%A2-t
#6
Jae-Woong Kim, Seong-Gi Kim, Sung-Hong Park
While phase imaging with a gradient echo (GRE) sequence is popular, phase imaging with balanced steady-state free precession (bSSFP) has been underexplored. The purpose of this study was to investigate anatomical and functional phase imaging with multiple phase-cycled bSSFP, in expectation of increasing spatial coverage of steep phase-change regions of bSSFP. Eight different dynamic 2D pass-band bSSFP studies at four phase-cycling (PC) angles and two TE /TR values were performed on rat brains at 9.4 T with electrical forepaw stimulation, in comparison with dynamic 2D GRE...
February 10, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28185433/model-based-iterative-reconstruction-for-single-shot-epi-at-7t
#7
Uten Yarach, Myung-Ho In, Itthi Chatnuntawech, Berkin Bilgic, Frank Godenschweger, Hendrik Mattern, Alessandro Sciarra, Oliver Speck
PURPOSE: To describe a model-based reconstruction strategy for single-shot echo planar imaging (EPI) that intrinsically accounts for k-space nonuniformity, Nyquist ghosting, and geometric distortions during rather than before or after image reconstruction. METHODS: Ramp sampling and inhomogeneous B0 field-induced distortion cause the EPI samples to lie on a non-Cartesian grid, thus requiring the nonuniform fast Fourier transform. Additionally, a 2D Nyquist ghost phase correction without the need for extra navigator acquisition is included in the proposed reconstruction...
February 10, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28177647/comprehensive-assessment-of-ankle-syndesmosis-injury-using-3d-isotropic-turbo-spin-echo-sequences-diagnostic-performance-compared-with-that-of-conventional-and-oblique-3-t-mri
#8
Minchul Kim, Yun Sun Choi, Min Sun Jeong, Mira Park, Tong Jin Chun, Jin Su Kim, Ki Won Young
OBJECTIVE: The objective of this study is to evaluate the diagnostic performance of 3D sampling perfection with application-optimized contrasts using different flip angle evolution (SPACE) sequences in the evaluation of ankle syndesmosis injuries, compared with that of conventional orthogonal MRI and oblique proton density-weighted turbo spin-echo (TSE) sequences performed with 3-T MRI. MATERIALS AND METHODS: This retrospective study included 98 patients with suspected ankle syndesmosis injuries who underwent both MRI and surgery...
February 8, 2017: AJR. American Journal of Roentgenology
https://www.readbyqxmd.com/read/28166493/a-gpu-accelerated-3d-coupled-sub-sample-estimation-algorithm-for-volumetric-breast-strain-elastography
#9
Bo Peng, Yuqi Wang, Timothy J Hall, Jingfeng Jiang
Our primary objective of this work was to extend a previously published 2D coupled sub-sample tracking algorithm for 3D speckle tracking in the framework of ultrasound breast strain elastography. In order to overcome heavy computational cost, we investigated the use of a graphic processing unit (GPU) to accelerate the 3D coupled sub-sample speckle tracking method. The performance of the proposed GPU implementation was tested using a tissue-mimicking (TM) phantom and in vivo breast ultrasound data. The performance of this 3D sub-sample tracking algorithm was compared with the conventional 3D quadratic subsample estimation algorithm...
January 31, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28161809/alteration-of-cardiac-deformation-in-acute-rejection-in-pediatric-heart-transplant-recipients
#10
Nitin Chanana, Charlotte S Van Dorn, Melanie D Everitt, Hsin Yi Weng, Dylan V Miller, Shaji C Menon
The objective of this study is to assess changes in cardiac deformation during acute cellular- and antibody-mediated rejection in pediatric HT recipients. Pediatric HT recipients aged ≤18 years with at least one episode of biopsy-diagnosed rejection from 2006 to 2013 were included. Left ventricular systolic S (SS) and SR (SSr) data were acquired using 2D speckle tracking on echocardiograms obtained within 12 h of right ventricular endomyocardial biopsy. A mixed effect model was used to compare cardiac deformation during CR (Grade ≥ 1R), AMR (pAMR ≥ 2), and mixed rejection (CR and AMR positive) versus no rejection (Grade 0R and pAMR 0 or 1)...
February 4, 2017: Pediatric Cardiology
https://www.readbyqxmd.com/read/28161394/magic-angle-effect-plays-a-major-role-in-both-t1rho-and-t2-relaxation-in-articular-cartilage
#11
Hongda Shao, Chantal Pauli, Shihong Li, Yajun Ma, Anthony S Tadros, Eric Y Chang, Guangyu Tang, Jiang Du
PURPOSE: To investigate the effect of sample orientation on T1rho and T2 values of articular cartilage in histologically confirmed normal and abnormal regions using a whole-body 3T scanner, providing information on the angular dependence of T1rho and T2 in clinical imaging. MATERIALS AND METHODS: Eight human cadaveric patellae were evaluated using a 2D CPMG sequence for T2 measurement as well as a 2D spin-locking prepared spiral sequence and a 3D magnetization-prepared angle-modulated partitioned-k-space spoiled gradient echo snapshots (3D MAPSS) sequence for T1rho measurement...
February 1, 2017: Osteoarthritis and Cartilage
https://www.readbyqxmd.com/read/28160410/mri-compatibility-of-several-early-transition-metal-based-alloys-and-its-influencing-factors
#12
Da-Bo Zhou, Shao-Gang Wang, Shao-Ping Wang, Hong-Jun Ai, Jian Xu
Magnetic resonance imaging (MRI) compatibility of three early transition metal (ETM) based alloys was assessed in vitro with agarose gel as a phantom, including Zr-20Nb, near-equiatomic (TiZrNbTa)90 Mo10 and Nb-60Ta-2Zr, together with pure tantalum and L605 Co-Cr alloy for comparison. The artifact extent in the MR image was quantitatively characterized according to the maximum area of 2D images and the total volume in reconstructed 3D images with a series of slices under acquisition by fast spin echo (FSE) sequence and gradient echo (GRE) sequence...
February 3, 2017: Journal of Biomedical Materials Research. Part B, Applied Biomaterials
https://www.readbyqxmd.com/read/28154124/benign-enhancing-foramen-magnum-lesions-clinical-report-of-a-newly-recognized-entity
#13
B J McGuinness, J P Morrison, S K Brew, M W Moriarty
Intradural extramedullary foramen magnum enhancing lesions may be due to meningioma, nerve sheath tumor, aneurysm, or meningeal disease. In this clinical report of 14 patients, we describe a novel imaging finding within the foramen magnum that simulates disease. The lesion is hyperintense on 3D-FLAIR and enhances on 3D gradient-echo sequences but is not seen on 2D-TSE T2WI. It occurs at a characteristic location related to the posterior aspect of the intradural vertebral artery just distal to the dural penetration...
February 2, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28152227/3d-myocardial-t1-mapping-using-saturation-recovery
#14
Giovanna Nordio, Markus Henningsson, Amedeo Chiribiri, Adriana D M Villa, Torben Schneider, René M Botnar
PURPOSE: To propose a 3D quantitative high-resolution T1 mapping technique, called 3D SASHA (saturation-recovery single-shot acquisition), which combines a saturation recovery pulse with 1D-navigator-based-respiratory motion compensation to acquire the whole volume of the heart in free breathing. The sequence was tested and validated both in a T1 phantom and in healthy subjects. MATERIALS AND METHODS: The 3D SASHA method was implemented on a 1.5T scanner. A diaphragmatic navigator was used to allow free-breathing acquisition and the images were acquired with a resolution of 1...
February 2, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28140650/comparison-of-a-fast-5-minute-shoulder-mri-protocol-with-a-standard-shoulder-mri-protocol-a-multiinstitutional-multireader-study
#15
Naveen Subhas, Alex Benedick, Nancy A Obuchowski, Joshua M Polster, Luis S Beltran, Jean Schils, Gina A Ciavarra, Soterios Gyftopoulos
OBJECTIVE: The purpose of this study was to compare the diagnostic performance of a 5-minute shoulder MRI protocol consisting of multiplanar 2D fast spin-echo (FSE) sequences with parallel imaging to that of a standard shoulder MRI protocol. MATERIALS AND METHODS: A retrospective review of 151 3-T MRI examinations of shoulders of 147 patients (mean age, 46.95 years) and 50 1.5-T MRI examinations of shoulders of 50 patients (mean age, 53.74 years) with four fast and five standard sequences from two academic centers between January 2014 and April 2015 was performed by three musculoskeletal radiologists...
January 31, 2017: AJR. American Journal of Roentgenology
https://www.readbyqxmd.com/read/28128490/the-role-of-holes-in-borophenes-an-ab%C3%A2-initio-study-of-their-structure-and-stability-with-and-without-metal-templates
#16
Naiwrit Karmodak, Eluvathingal D Jemmis
An electron-counting strategy starting from magnesium boride was used to show the inevitability of hexagonal holes in 2D borophene. The number (hole density, HD) and distribution of the hexagonal holes determine the binding energy per boron atom in monolayer borophenes. The relationship between binding energy and HD changes dramatically when the borophene is placed on a Ag(111) surface. The distribution of holes in borophenes on Ag(111) surfaces depends on the temperature. DFT calculations show that aside from the previously reported S1 and S2 borophene phases, other polymorphs may also be competitive...
January 27, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28121369/four-dimensional-diffusion-weighted-mr-imaging-4d-dwi-a-feasibility-study
#17
Yilin Liu, Xiaodong Zhong, Brian G Czito, Manisha Palta, Mustafa R Bashir, Brian M Dale, Fang-Fang Yin, Jing Cai
PURPOSE: Diffusion-weighted Magnetic Resonance Imaging (DWI) has been shown to be a powerful tool for cancer detection with high tumor-to-tissue contrast. This study aims to investigate the feasibility of developing a four-dimensional DWI technique (4D-DWI) for imaging respiratory motion for radiation therapy applications. MATERIALS/METHODS: Image acquisition was performed by repeatedly imaging a volume of interest (VOI) using an interleaved multislice single-shot echo-planar imaging (EPI) 2D-DWI sequence in the axial plane...
December 9, 2016: Medical Physics
https://www.readbyqxmd.com/read/28112827/new-method-to-characterize-and-correct-with-sub-%C3%A2%C2%B5s-precision-gradient-delays-in-bipolar-multispoke-rf-pulses
#18
Vincent Gras, Alexandre Vignaud, Alexis Amadon, Franck Mauconduit, Denis Le Bihan, Nicolas Boulant
PURPOSE: Small gradient delays with respect to radiofrequency (RF) events can have disastrous effects on the performance of bipolar spokes RF pulses used in parallel transmission (pTx). In this work, we propose a new method to characterize and correct this delay with sub-µs precision. METHODS: By determining experimentally the phase Δφ producing a 0 ° flip angle excitation in a α0°-α180°+Δφ bipolar two-spoke pulse configuration at multiple slice locations, we demonstrate the possibility of deducing the underlying gradient delay with precision...
January 23, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28111874/rationalising-heteronuclear-decoupling-in-refocussing-applications-of-solid-state-nmr-spectroscopy
#19
Ilya Frantsuzov, Suresh K Vasa, Matthias Ernst, Steven P Brown, Vadim Zorin, Arno P M Kentgens, Paul Hodgkinson
Factors affecting the performance of (1) H heteronuclear decoupling sequences for magic-angle spinning (MAS) NMR spectroscopy of organic solids are explored, as observed by time constants for the decay of nuclear magnetisation under a spin-echo (T2' ). By using a common protocol over a wide range of experimental conditions, including very high magnetic fields and very high radio-frequency (RF) nutation rates, decoupling performance is observed to degrade consistently with increasing magnetic field. Inhomogeneity of the RF field is found to have a significant impact on T2' values, with differences of about 20 % observed between probes with different coil geometries...
January 23, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28107094/dynamic-volume-assessment-of-hepatocellular-carcinoma-in-rat-livers-using-a-clinical-3t-mri-and-novel-segmentation
#20
Lorenzo A Orci, Graziano Oldani, Stephanie Lacotte, Florence Slits, Iris Friedli, Wolfgang Wirth, Christian Toso, Jean-Paul Vallée, Lindsey A Crowe
PURPOSE: In vivo liver cancer research commonly uses rodent models. One of the limitations of such models is the lack of accurate and reproducible endpoints for a dynamic assessment of growing tumor nodules. The aim of this study was to validate a noninvasive, true volume segmentation method using two rat hepatocellular carcinoma (HCC) models, correlating magnetic resonance imaging (MRI) with histological volume measurement, and with blood levels of α-fetoprotein. MATERIALS AND METHODS: We used 3T clinical MRI to quantify tumor volume with follow-up over time...
January 20, 2017: Journal of Investigative Surgery: the Official Journal of the Academy of Surgical Research
keyword
keyword
82640
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"