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Result : Searchterm 'Array' found in 8 terms [] and 53 definitions []
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Sensitivity EncodingInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
(SENSE) A MRI technique for relevant scan time reduction. The spatial information related to the coils of a receiver array are utilized for reducing conventional Fourier encoding. In principle, SENSE can be applied to any imaging sequence and k-space trajectories. However, it is particularly feasible for Cartesian sampling schemes. In 2D Fourier imaging with common Cartesian sampling of k-space sensitivity encoding by means of a receiver array enables to reduce the number of Fourier encoding steps.
SENSE reconstruction without artifacts relies on accurate knowledge of the individual coil sensitivities. For sensitivity assessment, low-resolution, fully Fourier-encoded reference images are required, obtained with each array element and with a body coil.
The major negative point of parallel imaging techniques is that they diminish SNR in proportion to the numbers of reduction factors. R is the factor by which the number of k-space samples is reduced. In standard Fourier imaging reducing the sampling density results in the reduction of the FOV, causing aliasing. In fact, SENSE reconstruction in the Cartesian case is efficiently performed by first creating one such aliased image for each array element using discrete Fourier transformation (DFT).
The next step then is to create a full-FOV image from the set of intermediate images. To achieve this one must undo the signal superposition underlying the fold-over effect. That is, for each pixel in the reduced FOV the signal contributions from a number of positions in the full FOV need to be separated. These positions form a Cartesian grid corresponding to the size of the reduced FOV.
The advantages are especially true for contrast-enhanced MR imaging such as dynamic liver MRI (liver imaging) , 3 dimensional magnetic resonance angiography (3D MRA), and magnetic resonance cholangiopancreaticography (MRCP).
The excellent scan speed of SENSE allows for acquisition of two separate sets of hepatic MR images within the time regarded as the hepatic arterial-phase (double arterial-phase technique) as well as that of multidetector CT.
SENSE can also increase the time efficiency of spatial signal encoding in 3D MRA. With SENSE, even ultrafast (sub second) 4D MRA can be realized.
For MRCP acquisition, high-resolution 3D MRCP images can be constantly provided by SENSE. This is because SENSE resolves the presence of the severe motion artifacts due to longer acquisition time. Longer acquisition time, which results in diminishing image quality, is the greatest problem for 3D MRCP imaging.
In addition, SENSE reduces the train of gradient echoes in combination with a faster k-space traversal per unit time, thereby dramatically improving the image quality of single shot echo planar imaging (i.e. T2 weighted, diffusion weighted imaging).
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• Related Searches:
    • Sense Coil
    • Parallel Imaging Technique
    • Simultaneous Acquisition of Spatial Harmonics
    • Fourier Transformation
    • Cartesian Sampling
 
Further Reading:
  News & More:
Image Characteristics and Quality
   by www.sprawls.org    
MRI Resources 
Resources - NMR - Research Labs - Distributors - Implant and Prosthesis - Jobs pool
 
Excelart AG™ with PianissimoInfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
http://www.medical.toshiba.com/clinical/radiology/15texcelart.htm From Toshiba America Medical Systems Inc.;
the EXCELART is a superconducting whole body MRI system with a short wide-bore magnet, operating at 1.5 T. It features powerful high-speed gradients with a revolutionary gradient acoustic noise reduction system: Pianissimo. The dramatic reduction of gradient acoustic noise by Pianissimo greatly enhances patient comfort during exams. The standard array platform and a wide range of array coils ensure excellent images. A powerful 64-bit RISC-based computer system and newly developed array processor realize high productivity.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Cylindrical Wide Short Bore
Opt. (WIP) Single and Multi Voxel
SYNCHRONIZATION
ECG: standard; peripheral: optional, respiratory gating
PULSE SEQUENCES
SE, FE, IR, FastSE, FastIR, FastFLAIR, Fast STIR, FastFE, FASE, Hybrid EPI, Multi Shot EPI; Angiography: 2D(gate/non-gate)/3D TOF, SORS-STC
IMAGING MODES
Single, multislice, volume study
TR
3.5-30000 msec
TE
8 msec min. SE; 1.2 msec min. FE
SINGLE/MULTI SLICE
less than 0.015 (256x256)
FOV
2 cm
1.0 min. 2-DFT: 0.2 min. 3-DFT
Up to 1024
MEASURING MATRIX
32-1024, phase;; 64-1024, freq.
PIXEL INTENSITY
256 gray levels
BORE DIAMETER
or W x H
65.5 cm, patient aperture
MAGNET WEIGHT
4050 kg (bare magnet incl. L-He)
H*W*D
235 x 219 x 199 cm
COOLING SYSTEM TYPE
Closed-loop water-cooled
CRYOGEN USE
Liquid helium: approx. less than 0.05 L/hr
STRENGTH
25 mT/m
5-GAUSS FRINGE FIELD
2.5 m / 4.0 m
Passive, active, auto-active
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MRI Resources 
Knee MRI - Software - Breast MRI - Pregnancy - MRA - Health
 
Excelart XG™ with PianissimoInfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
http://www.medical.toshiba.com/clinical/radiology/15texcelart.htm From Toshiba America Medical Systems Inc.;
the EXCELART is a superconducting whole body MRI system with a short wide-bore magnet, operating at 1.5 T. It features powerful high-speed gradients with a revolutionary gradient acoustic noise reduction system: Pianissimo. The dramatic reduction of gradient acoustic noise by Pianissimo greatly enhances patient comfort during exams. The standard array platform and a wide range of array coils ensure excellent images. A powerful 64-bit RISC-based computer system and newly developed array processor realize high productivity.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Cylindrical Wide Short Bore
Optional (WIP)
SYNCHRONIZATION
ECG/peripheral, respiratory gating
PULSE SEQUENCES
SE, FE, IR, FastSE, FastIR, FastFLAIR, Fast STIR, FastFE, FASE, Hybrid EPI, Multi Shot EPI; Angiography: 2D(gate/non-gate)/3D TOF, SORS-STC
IMAGING MODES
Single, multislice, volume study
TR
2.6-30000 msec
TE
8 msec min. SE; 0.9 msec min. FE
SINGLE/MULTI SLICE
less than 0.011 (256x256)
FOV
2 cm
1.0 min. 2-DFT: 0.2 min. 3-DFT
Up to 1024
MEASURING MATRIX
32-1024, phase;; 64-1024, freq.
PIXEL INTENSITY
256 gray levels
BORE DIAMETER
or W x H
65.5 cm, patient aperture
MAGNET WEIGHT
4050 kg (bare magnet incl. L-He)
H*W*D
235 x 219 x 199 cm
POWER REQUIREMENTS
380/400/415/440/480 V
COOLING SYSTEM TYPE
Closed-loop water-cooled
CRYOGEN USE
Liquid helium: approx. less than 0.05 L/hr
STRENGTH
25 mT/m
5-GAUSS FRINGE FIELD
2.5 m / 4.0 m
Passive, active, auto-active
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Further Reading:
  News & More:
Angio, cardiac imaging top list for MR and CT
1999   by www.diagnosticimaging.com    
Searchterm 'Array' was also found in the following services: 
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G-SCANInfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.esaote.de/04_kernspin/gscan/gscan.htm From Esaote S.p.A.; Esaote introduced the new G-SCAN at the RSNA in Dec. 2004. The G-SCAN covers almost all musculoskeletal applications including the spine. The tilting gantry is designed for scanning in weight-bearing positions. This unique MRI scanner is developed in line with the Esaote philosophy of creating high quality MRI systems that are easy to install and that have a low breakeven point.
Device Information and Specification
CLINICAL APPLICATION
CONFIGURATION
Spine, extremity, shoulder, flex coil, knee dual phased array, ankle//foot dual phased array, hand//wrist dual phased array
PULSE SEQUENCES
SE, GE, IR, STIR, TSE, 3D CE, GE-STIR, 3D GE, ME, TME, HSE
IMAGING MODES
Single, multislice, volume study, fast scan, multi slab, cine
FOV
100 up to 350 mm, 25 mm displayed
512 x 512
MEASURING MATRIX
256 x 256 maximum
MAGNET TYPE
Permanent
BORE DIAMETER
or W x H
33 cm H, open
POWER REQUIREMENTS
100/110/200/220/230/240 V
STRENGTH
25 mT/m
5-GAUSS FRINGE FIELD
180 cm
Passive
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MRI Resources 
Software - Diffusion Weighted Imaging - Stent - Cardiovascular Imaging - MR Guided Interventions - Liver Imaging
 
MAGNETOM Trio™ (TIM System)InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.
 
www.medical.siemens.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&langId=-11&catalogId=-11&catTree=100001%2C12786%2C12754&level=0&productId=145739 From Siemens Medical Systems;
The Magnetom Trio™, a 3T whole body MRI system with Tim (total imaging matrix technology), targets clinical applications such as abdominal, cardiac, spine, whole body and orthopedics. TIM enables flexible coil combinations for high resolution imaging of large anatomical areas without the need to change coils.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Short bore
CP head, CP integrated body coil, neck matrix, breast array, 8-channel knee array, CP wrist, shoulder array, CP extremity
Yes/Mutli-nuclear MRS
PULSE SEQUENCES
SE, IR, 2D/3D TurboSE, Turbo IR, Dark-Fluid IR, True IR, 2D/3D MEDIC, 2D/3D GRE FLASH, 2D/3D GRE FISP, 2D/3D PSIF, 2D TurboFLASH, 3D MP-RAGE, 3D TurboFLASH, 2D/3D TOF angiography, MTC, TONE with 3D TOF MRA, GMR, LOTA
IMAGING MODES
Single, multislice, volume study, multi angle, multi oblique
SINGLE/MULTI SLICE
178 images/sec at 256 x 256 at 100% FOV
40 cm
Min 2D/3D: 0.1/0.05 mm
1024 x 1024 full screen display
MEASURING MATRIX
64 x 64 to 1024 x 1024
10 micrometer
60 cm
MAGNET WEIGHT
12000 kg
H*W*D
221 x 244 x 213 cm
POWER REQUIREMENTS
380/400/420/440/480 V
COOLING SYSTEM TYPE
Single cryogen, 2 stage refrig.
0.12 L/hr helium
STRENGTH
40 - 45 mT/m
200 mT/m/ms
5-GAUSS FRINGE FIELD
3.4 m / 5.9 m
Passive, act.; 1st order std./2nd opt.
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MRI Resources 
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