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Result : Searchterm 'Flow' found in 15 terms [] and 98 definitions []
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Searchterm 'Flow' was also found in the following services: 
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Flow Related Enhancement
 
(FRE) Flow related enhancement could be seen most for blood flow, but also for other liquids with some MR imaging techniques, as an increase in intensity due to the washout of saturated spins. FRE provides positive contrast ("bright blood") of vascular details in time of flight MRA as well as the physiologic characterization of blood flow.
If stationary spins within the scanned region experience only an incomplete T1 relaxation between the repeated radio frequency (RF) excitations, this results in fewer signal of the stationary tissue (compared to inflowing blood with completely relaxed spins). The degree of the flow related enhancement is proportional to the blood flow velocity and the used repetition time. The use of flow compensation (gradient moment nulling) improves the FRE especially in gradient echo sequences.
 
Images, Movies, Sliders:
 TOF-MRA Circle of Willis Inverted MIP  Open this link in a new window
    

 Circle of Willis, Time of Flight, MIP  Open this link in a new window
    
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Further Reading:
  Basics:
Conventional MRI and MR Angiography of Stroke
2012   by www.mc.vanderbilt.edu    
Searchterm 'Flow' was also found in the following services: 
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Radiology  (25) Open this link in a new windowUltrasound  (120) Open this link in a new window
Radio Frequency Overflow 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
NAME
Radio frequency overflow, data clipping
DESCRIPTION
Image non-uniform
REASON
Signal too intense
HELP
Manually decrease of the receiver gain
The received radio frequency signal is too strong, parts of the signal get lost by converting from analog to digital, resulting in a washed out image.
mri safety guidance
Image Guidance
Auto-prescanning usually adjusts the amplification at the receiver in a way, that the received signal could be processed without any loss. Else the receiver gain must be corrected manually.

See also Data Clipping Artifact, Artifact Overview and Artifacts Reduction Index.
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• View the DATABASE results for 'Radio Frequency Overflow Artifact' (2).Open this link in a new window

 
Further Reading:
  Basics:
RF Overflow Artifacts
   by www.mritutor.org    
  News & More:
Magnetic Resonance Imaging (MRI)
2003   by www.hull.ac.uk    
MRI Resources 
Fluorescence - Lung Imaging - MR Myelography - MRI Training Courses - Jobs pool - Stent
 
Inflow Magnetic Resonance AngiographyMRI Resource Directory:
 - MRA -
 
(I MRA) In MR imaging, inflowing non-saturated fluid gives a higher signal intensity than stationary tissue. This effect makes it especially useful for imaging of flowing blood. Other factors such as susceptibility and spin saturation, can affect the signal of the blood within the vessels. Furthermore turbulence is part of normal blood flow and can decrease signal intensity.

See also Time of Flight Angiography.
 
Images, Movies, Sliders:
 TOF-MRA Circle of Willis Inverted MIP  Open this link in a new window
    

 Circle of Willis, Time of Flight, MIP  Open this link in a new window
    
SlidersSliders Overview

 
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Searchterm 'Flow' was also found in the following services: 
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News  (51)  Resources  (20)  Forum  (14)  
 
Flow Sensitive Alternating Inversion RecoveryInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
(FAIR) In this sequence 2 inversion recovery images are acquired, one with a nonselective and the other with a slice selective inversion pulse. The z-magnetization in the first sequence is independent of flow. Inflowing spins give z-magnetization from second pulse. A major signal loss in FAIR is the T1 relaxation of tagged blood in transit to the imaging slice. Sharper edges of the inversion pulse give narrow spacing between the inversion edge and the 1st slice because reduced transit time gives lower T1 relaxation induced signal loss. The difference of the images in a consequence contains information proportional to flow (blood partition coefficient). Standard adiabatic inversion RF pulse does not have good slice-profile, because of power/SAR limitation. A c-shaped frequency offset corrected inversion (FOCI) RF pulse can help to increase the signal.
Perfusion imaging, e.g. myocardial, using tissue water as endogenous contrast is suggested.
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Searchterm 'Flow' was also found in the following services: 
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Radiology  (25) Open this link in a new windowUltrasound  (120) Open this link in a new window
Multiple 2 Dimensional (Inflow) MR AngiographyInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.MRI Resource Directory:
 - MRA -
 
(M2DMRA) The M2D technique can be used to image both fast and slow flow, due to good refreshment of flowing blood. Using overlapping slices can reduce staircase artifacts, which might be seen in projection of the slice thickness.

See also Time of Flight Angiography.
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MRI Resources 
Liver Imaging - Universities - Implant and Prosthesis - Mobile MRI - Services and Supplies - Crystallography
 
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