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Result : Searchterm 'Gating' found in 4 terms [] and 63 definitions []
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Searchterm 'Gating' was also found in the following services: 
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News  (4)  Resources  (2)  Forum  (1)  
 
Fast Relaxation Fast Spin EchoInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
(FRFSE, FR-FSE) The fast relaxation fast spin echo sequence provides high signal intensity of fluids even with short repetition times, and can be used with parallel imaging techniques for short breath hold imaging or respiratory gating for free-breathing, high isotropic resolution MR imaging. After signal decay at the end of the echo train, a negative 90° pulse align spins with long T2 from the transverse plane to the longitudinal plane, leading to a much faster recovery of tissues with long T2 time to the equilibrium and thus better contrast between tissues with long and short T2.
Fast relaxation FSE has advantages also for volumetric imaging as the TR can be substantially reduced and thus the scan time. The sequence can be post processed with maximum intensity projection, surface or volume rendering algorithms to visualize anatomical details in brain or spine MRI. Cerebro spinal fluid pulsation artifacts, often problematic in the cervical or thoracic spine may be reduced by radial sampling, in particular when combined with acquisitions of the PROPELLER type.

See also Fast spin echo, Driven Equilibrium.
 
Images, Movies, Sliders:
 Shoulder Sagittal T2 FatSat FRFSE  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 Shoulder Axial T2 FatSat FRFSE  Open this link in a new window
 Shoulder Coronal T2 FatSat FRFSE  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 
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Radiology  (5) Open this link in a new windowUltrasound  (7) Open this link in a new window
Flow ArtifactInfoSheet: - Artifacts - 
Case Studies, 
Reduction Index, 
etc.MRI Resource Directory:
 - Artifacts -
 
Quick Overview
Please note that there are different common names for this artifact.
Artifact Information
DESCRIPTION
Vascular ghosts (ghosting artifact), anomalous intensities in images
REASON
Movement of body fluids
HELP
Flow compensation, presaturation, triggering
Flow effects in MRI produce a range of artifacts, e.g. intravascular signal void by time of flight effects; turbulent dephasing and first echo dephasing, caused by flowing blood.
Through movement of the hydrogen nuclei (e.g. blood flow), there is a location change between the time these nuclei experience a radio frequency pulse and the time the emitted signal is received (because the repetition time is asynchronous with the pulsatile flow).
The blood flow occasionally produces intravascular high signal intensities due to flow related enhancement, even echo rephasing and diastolic pseudogating. The pulsatile laminar flow within vessels often produces a complex multilayered band that usually propagates outside the head in the phase encoded direction. Blood flow artifacts should be considered as a special subgroup of motion artifacts.
mri safety guidance
Image Guidance
Artifacts can be reduced by reduction of phase shifts with flow compensation (gradient moment nulling), suppression of the blood signal with saturation pulses parallel to the slices, synchronization of the imaging sequence with the heart cycle (cardiac triggering) or can be flipped 90° by swapping the phase//frequency encoding directions.

See also Flow Related Enhancement and Flow Effects.
 
Images, Movies, Sliders:
 Knee MRI Sagittal T1 003  Open this link in a new window
 
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• View the DATABASE results for 'Flow Artifact' (6).Open this link in a new window

 
Further Reading:
  News & More:
MRI measure of blood flow over atherosclerotic plaque may detect dangerous plaque
Friday, 5 April 2013   by www.sciencecodex.com    
Advanced Visualization Techniques Could Change the Paradigm for Diagnosis and Treatment of Heart Disease
Thursday, 31 May 2012   by www.sciencedaily.com    
MRI Resources 
Developers - MRA - Collections - Pathology - Quality Advice - PACS
 
Infinion 1.5TPanorama 0.2InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
From Philips Medical Systems; www.medical.philips.com/main/products/mri/products/infinion1.5t/features/ Philips Infinion 1.5 T is designed to maximize the efficiency and quality of patient care. Developed with the patient in mind, the Infinion is the shortest and most open 1.5T scanner available. The unique 'ultra short' 1.4 m magnet assures patient comfort and acceptance without compromising image quality and clinical performance.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Ultra short bore
Head, head / neck, integrated C-spine, L/T spine array, small large GP coils, body flex array, torso pelvis array, breast array, endocavitary, shoulder array, lower extremity, hand / wrist, cardiac, PV array
SYNCHRONIZATION
ECG/peripheral, respiratory gating
PULSE SEQUENCES
SE, TSE, SS TSE, EPI, IR, STIR, FLAIR, FFE, TFE, T1 TFE, T2 TFE, Presat, Fatsat, MTC, Diff-opt., Angiography: PCA, MCA, TOF
IMAGING MODES
Single slice, single volume, multi slice, multi volume
TR
3.1 msec minimum
TE
0.9 msec minimum
SINGLE/MULTI SLICE
80 images/sec std.; up to320 opt.@256
FOV
0.4 - 56 cm
2D: 0.3 mm; 3D: 0.2 mm
1024 x 1024
MEASURING MATRIX
8 x 8 to 1024 x 1024
PIXEL INTENSITY
256 gray scale
BORE DIAMETER
or W x H
60 cm diameter (patient)
MAGNET WEIGHT
4100 kg w/cryogen's
H*W*D
233 (lead fitted) x 198 x 140 cm
POWER REQUIREMENTS
400/480 V
COOLING SYSTEM TYPE
Closed loop, chilled water
CRYOGEN USE
0.06 L/hr helium
STRENGTH
30 mT/m
5-GAUSS FRINGE FIELD
3.0 m / 5.0 m
Passive/active
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• View the DATABASE results for 'Infinion 1.5T™' (2).Open this link in a new window

Searchterm 'Gating' was also found in the following services: 
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News  (4)  Resources  (2)  Forum  (1)  
 
Intera 0.5TPanorama 0.2InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.medical.philips.com/de/products/mri/products/ From Philips Medical Systems;
this low field MRI system of the Intera-family is onto diagnostic safety and flexibility aligned - cost effective and with high patient acceptance.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Short bore compact
Standard: head, body, C1, C3; Optional: Small joint, flex-E, flex-R, endocavitary (L and S), dual TMJ, knee, neck, T/L spine, breast; Optional phased array: Spine, pediatric, 3rd party connector, Flex-S-M-L, flex body, flex cardiac, neuro-vascular, head
SYNCHRONIZATION
ECG/peripheral: Optional/yes, respiratory gating
PULSE SEQUENCES
SE, Modified-SE (TSE), DAVE, STIR, FLAIR, SPIR, MTC, Dynamic, Keyhole, CLEAR, Q Flow, Balanced FFE, Multi Chunk 3D, Multi Stack 3D, FFE-EPI, SE-EPI, IR-EPI, GRASE, Diffusion Imaging, Perfusion Imaging;; Angiography: Inflow MRA, TONE, PCA, CE MRA
IMAGING MODES
Single Slice 2D , Multi Single Slice 2D, Multi Slice 2D, 3D, Multi Chunk 3D, Multi Stack 3D
TR
Min. 2.9 (Omni) msec
TE
Min. 1.0 (Omni) msec
SINGLE/MULTI SLICE
RapidView Recon. greater than 500 @ 256 Matrix
FOV
Max. 53 cm
0.1 mm (Omni)
128 x 128, 256 x 256,512 x 512,1024 x 1024
MEASURING MATRIX
Variable in 1% increments
PIXEL INTENSITY
Lum.: 120 cd/m2; contrast: 150:1
Variable (op. param. depend.)
60 x 60 cm
MAGNET WEIGHT
2500 kg
H*W*D
240 x 188 x 157 cm
POWER REQUIREMENTS
380/400 V
CRYOGEN USE
0.03 L/hr helium
STRENGTH
23 mT/m (Omni)
5-GAUSS FRINGE FIELD
2.1 m / 2.8 m
Passive and dynamic
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• View the DATABASE results for 'Intera 0.5T™' (2).Open this link in a new window

Searchterm 'Gating' was also found in the following services: 
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Radiology  (5) Open this link in a new windowUltrasound  (7) Open this link in a new window
Intera 1.0TPanorama 0.2InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.medical.philips.com/de/products/mri/products/ From Philips Medical Systems; the Intera-family offers with this mid field system maximum efficiency, flexibility and performance. All Philips MR products contain SENSE (coil SENSitivity Encoding) technology - that increases scanning speed.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Short bore compact
Standard: head, body, C1, C3; Optional: Small joint, flex-E, flex-R, endocavitary (L and S), dual TMJ, knee, neck, T/L spine, breast; Optional phased array: Spine, pediatric, 3rd party connector, Optional SENSE Coils: Flex-S-M-L, Flex Body, Flex Cardiac
Optional
SYNCHRONIZATION
ECG/peripheral: Optional/yes, respiratory gating
PULSE SEQUENCES
SE, Modified-SE, IR (T1, T2, PD), STIR, FLAIR, SPIR, FFE, T1-FFE, T2-FFE, Balanced FFE, TFE, Balanced TFE, Dynamic, Keyhole, 3D, Multi Chunk 3D, Multi Stack 3D, K Space Shutter, MTC, TSE, Dual IR, DRIVE, EPI, Cine, 2DMSS, DAVE, Mixed Mode; Angiography: Inflow MRA, TONE, PCA, CE MRA
IMAGING MODES
Single Slice 2D , Multi Single Slice 2D, Multi Slice 2D, 3D, Multi Chunk 3D, Multi Stack 3D
TR
Min. 2.9 (Omni) msec, 1.6 (Power) msec
TE
Min. 1.0 (Omni) msec, 0.7 (Power) msec
SINGLE/MULTI SLICE
RapidView Recon. greater than 500 @ 256 Matrix
FOV
Max. 53 cm
0.1 mm(Omni), 0.05 mm (Power)
128 x 128, 256 x 256,512 x 512,1024 x 1024 (64 for Bold img)
MEASURING MATRIX
Variable in 1% increments
PIXEL INTENSITY
Lum.: 120 cd/m2; contrast: 150:1
Variable (op. param. depend.)
60 x 60 cm
MAGNET WEIGHT
2700 kg
H*W*D
240 x 188 x 157 cm
POWER REQUIREMENTS
380/400 V
CRYOGEN USE
0.03 L/hr helium
STRENGTH
23 mT/m (Omni), 30 (Power) mT/m
5-GAUSS FRINGE FIELD
2.3 m / 3.3 m
Passive and dynamic
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• View the DATABASE results for 'Intera 1.0T™' (2).Open this link in a new window

MRI Resources 
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