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Searchterm 'Cation' was also found in the following services: 
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News  (222)  Resources  (163)  Forum  (75)  
 
Signa HDx 3.0T™InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.
 
gehealthcare.com/euen/mri/products/signa-hdx-3t/index.html From GE Healthcare;
The Signa HDx MRI system is GE's leading edge whole body magnetic resonance scanner designed to support high resolution, high signal to noise ratio, and short scan times.
Signa HDx 3.0T offers new technologies like ultra-fast image reconstruction through the new XVRE recon engine, advancements in parallel imaging algorithms and the broadest range of premium applications. The HD applications, PROPELLER (high-quality brain imaging extremely resistant to motion artifacts), TRICKS (contrast-enhanced angiographic vascular lower leg imaging), VIBRANT (for breast MRI), LAVA (high resolution liver imaging with shorter breath holds and better organ coverage) and MR Echo (high-definition cardiac images in real time) offer unique capabilities.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Compact short bore
Head and body coil, T/R quadrature head; optional coils e.g., T/R phased array extremity abdomen, spine, breast, knee, shoulder, cardiac imaging coils
SYNCHRONIZATION
ECG/peripheral, respiratory gating
PULSE SEQUENCES
SE, IR, 2D/3D GRE, RF-spoiled GRE, 2DFGRE, 2DFSPGR, 3DFGRE, 3DFSPGR, 3DTOFGRE, 3DFSPGR, 2DFSE, 2DFSE-XL, 2DFSE-IR, T1-FLAIR, SSFSE, EPI, DW-EPI, BRAVO, Angiography: 2D/3D TOF, 2D/3D phase contrast vascular
IMAGING MODES
Single, multislice, volume study, fast scan, multi slab, cine, localizer
1 cm to 40 cm continuous
2D 0.5 mm; 3D 0.1 mm
1024 x 1024
PIXEL INTENSITY
256 gray levels
60 cm
MAGNET WEIGHT
12000 kg
H*W*D
240 x 2216,6 x 201,6 cm
POWER REQUIREMENTS
480 or 380/415, 3 phase ||
COOLING SYSTEM TYPE
Closed-loop water-cooled grad.
0.03 L/hr helium
STRENGTH
23 - 50 mT/m
80 - 150 mT/m/ms
5-GAUSS FRINGE FIELD
2.8 m / 5.0 m
second and high order
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MRI Resources 
Homepages - Libraries - Lung Imaging - Movies - Education - Examinations
 
Aliasing ArtifactInfoSheet: - Artifacts - 
Case Studies, 
Reduction Index, 
etc.MRI Resource Directory:
 - Artifacts -
 
Quick Overview
Please note that there are different common names for this MRI artifact.
Artifact Information
NAME
Aliasing, backfolding, foldover, phase wrapping, wrap around
DESCRIPTION
Image wrap around
Aliasing is an artifact that occurs in MR images when the scanned body part is larger than field of view (FOV). As a consequence of the acquired k-space frequencies not being sampled densely enough, whereby portions of the object outside of the desired FOV get mapped to an incorrect location inside the FOV. The cyclical property of the Fourier transform fills the missing data of the right side with data from behind the FOV of the left side and vice versa. This is caused by a too small number of samples acquired in, e.g. the frequency encoding direction, therefore the spectrums will overlap, resulting in a replication of the object in the x direction.
Aliasing in the frequency direction can be eliminated by twice as fast sampling of the signal or by applying frequency specific filters to the received signal.
A similar problem occurs in the phase encoding direction, where the phases of signal-bearing tissues outside of the FOV in the y-direction are a replication of the phases that are encoded within the FOV. Phase encoding gradients are scaled for the field of view only, therefore tissues outside the FOV do not get properly phase encoded relative to their actual position and 'wraps' into the opposite side of the image.
mri safety guidance
Image Guidance
Use a larger FOV, RFOV or 3D Volume, apply presaturation pulses to the undesired tissue, adjust the position of the FOV, or select a small coil which will only receive signal from objects inside or near the coil. The number of phase encoding steps must be increased in phase direction, unfortunately resulting in longer scan times.
When this is not possible it can be corrected by oversampling the data. Aliasing is eliminated by Oversampling in frequency direction. No Phase Wrap (Foldover Suppression) options typically correct the phase encoding by doubling the field of view, doubling the number of phase encodes (to keep resolution constant) and halving the number of averages (to keep scan time constant) then discarding the additional data and processing the image within the desired field of view (but this is more time consuming).
Tissue outside this doubled area can be folded nevertheless into the image as phase wrap. In this case combine more than 2 number of excitations / number of signal averages with foldover suppression.
See also Aliasing, Foldover Suppression, Oversampling, and Artifact Reduction - Aliasing.
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• View the DATABASE results for 'Aliasing Artifact' (11).Open this link in a new window

MRI Resources 
Examinations - Education - Brain MRI - Online Books - Safety Products - Stimulator pool
 
Combidex®InfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.MRI Resource Directory:
 - Contrast Agents -
 
Combidex® is the brand name (same as Sinerem®) for an ultrasmall superparamagnetic iron oxide (USPIO) in the development pipeline to detect metastatic disease in lymph nodes. Metastatic lymph nodes show less uptake of this MRI contrast agent, which results in less signal decrease and allows the differentiation of normal lymph nodes from normal-sized, metastatic nodes. Combidex® has also potential to be used as a functional molecular imaging agent.
In March 2005, AMAG Pharmaceuticals Inc received an approvable letter from the U.S. Food and Drug Administration with respect to Combidex subject to certain conditions.
See also Ferumoxtran, Drug Development and Approval Process USA, Molecular Imaging and Classifications, Characteristics, etc.
Drug Information and Specification
NAME OF COMPOUND
Ferumoxtran, USPIO, AMI-227
CENTRAL MOIETY
Fe3+/Fe2+
CONTRAST EFFECT
T1, predominantly T2
r1=25, r2=160, B0=0.47T, r1=23.3, r2=48.9, B0=0.47T
PHARMACOKINETIC
Vascular, lymph v. hepatocyte (AG-USPIO)
DOSAGE
2.6 mg Fe/kg
PREPARATION
Suspend in an isotonic glucose solution
INDICATION
Lymph node, (MR angiography vascular, staging of RES-directed liver diseases)
DO NOT RELY ON THE INFORMATION PROVIDED HERE, THEY ARE
NOT A SUBSTITUTE FOR THE ACCOMPANYING PACKAGE INSERT!
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• View the DATABASE results for 'Combidex®' (6).Open this link in a new window


• View the NEWS results for 'Combidex®' (1).Open this link in a new window.
 
Further Reading:
  Basics:
The demise of Combidex - Sinerem
Wednesday, 24 March 2010   by www.wellsphere.com    
  News & More:
Combidex, MRI, and identification of nodal metastases
Wednesday, 17 June 2009   by prostatecancerinfolink.net    
Superparamagnetic Iron Oxide–enhanced MR Imaging of Head and Neck Lymph Nodes1
Searchterm 'Cation' was also found in the following services: 
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News  (222)  Resources  (163)  Forum  (75)  
 
ENCORE 0.5T™InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.isoltech.co.kr/english/product/05t.htm 'MRI system is not an expensive equipment anymore. ENCORE developed by ISOL Technology is a low cost MRI system with the advantages like of the 1.0T MRI scanner. Developed specially for the overseas market, the ENCORE is gaining popularity in the domestic market by medium sized hospitals.
Due to the optimum RF and Gradient application technology. ENCORE enables to obtain high resolution imaging and 2D/3D Angio images which was only possible in high field MR systems.'
- Less consumption of the helium gas due to the ultra-lightweight magnet specially designed and manufactured for ISOL. - Cost efficiency MR system due to air cooling type (equivalent to permanent magnetic). - Patient processing speed of less than 20 minutes.'
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Short bore compact
Head, C-spine, L-spine, TMJ, Knee, Shoulder, General purpose, Phased Array System: 4 digital receiver channels (Up to 12 channels)
SYNCHRONIZATION
ECG/peripheral: Optional/yes, respiratory gating
SINGLE/MULTI SLICE
Image reconstruction time (2562 ) : 0.02 s
FOV
40 cm
BORE DIAMETER
or W x H
58 cm diameter
MAGNET WEIGHT
3200 kg
H*W*D
200 x 168 x 187 cm
COOLING SYSTEM TYPE
Air-cooled coil and amplifier
CRYOGEN USE
0.05 L/hr helium
STRENGTH
15 mT/m
5-GAUSS FRINGE FIELD
2.3 m / 3.1 m
Passive and active
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• View the DATABASE results for 'ENCORE 0.5T™' (2).Open this link in a new window

MRI Resources 
Process Analysis - PACS - MRI Technician and Technologist Career - Image Quality - Blood Flow Imaging - Libraries
 
Foldover SuppressionInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
A problem occurs in the phase encoding direction, where the phases of signal-bearing tissues outside of the FOV in the y-direction are a replication of the phases that are encoded within the FOV. This signal will be mapped (wrapped, backfolded) back into the image at incorrect locations.
Foldover suppression (phase oversampling, no phase wrap) is a user-selectable parameter that maps this signal to its correct location outside the FOV, then discards any signal from outside the FOV before displaying the image. In order to be able to choose this parameter, in most cases more than an average is necessary.

See also Phase Wrapping Artifact and Oversampling.
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• View the DATABASE results for 'Foldover Suppression' (4).Open this link in a new window

MRI Resources 
RIS - Mobile MRI - Spectroscopy pool - Process Analysis - Spine MRI - Devices
 
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