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Result : Searchterm 'Radio Frequency' found in 12 terms [] and 63 definitions []
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Searchterm 'Radio Frequency' was also found in the following services: 
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News  (7)  Resources  (2)  Forum  (3)  
 
Radio Frequency Quadrature ArtifactInfoSheet: - Artifacts - 
Case Studies, 
Reduction Index, 
etc.MRI Resource Directory:
 - Artifacts -
 
Quick Overview
Artifact Information
NAME
Radio frequency quadrature
DESCRIPTION
Bright spot in the center of the image, ghosting
REASON
RF detection circuitry problem
HELP
Call the service
Radio frequency quadrature artifacts occur when the detector channels of the quadrature detector are disturbed.
A DC offset of one amplifier output can e.g., produce a bright point in the center of the field of view (see also central point artifact), or a higher gain of one detector channel can generate diagonally ghosting.
mri safety guidance
Image Guidance
Radio frequency quadrature artifacts are technical faults and must be eliminated by the service.
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Further Reading:
  News & More:
Magnetic Resonance Imaging (MRI)
2003   by www.hull.ac.uk    
Searchterm 'Radio Frequency' was also found in the following service: 
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Radiology  (2) Open this link in a new window
Radio Frequency Spoiled Steady State Acquisition Rewound Gradient EchoInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.MRI Resource Directory:
 - Sequences -
 
(RSSARGE) A sequence with spoiled gradient echoes.
See Spoiled Gradient Echo Sequence.
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• View the DATABASE results for 'Radio Frequency Spoiled Steady State Acquisition Rewound Gradient Echo' (2).Open this link in a new window

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B1Forum -
related threads
 
[B1] A conventional symbol for the radio frequency field strength (another symbol historically used, is H1). In MRI, B1 labels the field produced by the radio frequency coil.
The B1 field is often conceived of two vectors rotating in opposite directions, usually in a plane transverse to B0. At the Larmor frequency, the vector rotating in the same direction as the precessing spins will interact strongly with the spins.
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• View the DATABASE results for 'B1' (1346).Open this link in a new window

 
Further Reading:
  News & More:
Implementation of Dual-Source RF Excitation in 3 T MR-Scanners Allows for Nearly Identical ADC Values Compared to 1.5 T MR Scanners in the Abdomen
Wednesday, 29 February 2012   by www.plosone.org    
Turbo-FLASH Based Arterial Spin Labeled Perfusion MRI at 7 T
Thursday, 20 June 2013   by www.plosone.org    
Mapping of low flip angles in magnetic resonance(.pdf)
Saturday, 1 January 2011   by www.hal.inserm.fr    
Searchterm 'Radio Frequency' was also found in the following services: 
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News  (7)  Resources  (2)  Forum  (3)  
 
Bird Cage CoilInfoSheet: - Coils - 
Intro, 
Overview, 
etc.MRI Resource Directory:
 - Coils -
 
A RF coil, often a transmit receive coil with a number of wires running along the z-direction, arranged to give a cosine current variation around the circumference of the coil, which looks like a bird cage. The bird cage coil works on a different principle to conventionally tuned local and surround coils in that it behaves like a tuned transmission line with one complete cycle of standing wave around the circumference. The frequency supply is generated by an oscillator, which is modulated to form a shaped pulse by a product detector controlled by the waveform generator. The signal must be amplified to 1000's of watts. This can be done using either solid state electronics, valves or a combination of both.
The bird cage coil design provides the best field homogeneity of all RF imaging coils.
One advantage is that it is simple to produce an exceedingly uniform B1 radio frequency field over most of the coil's volume, with the result of images with a high degree of uniformity.
A second advantage is that nodes with zero voltage occur 90° away from the driven part of the coil, thus facilitating the introduction of a second signal in quadrature, which produces a circularly polarized radio frequency field.
This type of volume coil is used for brain (head) MRI, or MR imaging of joints, such as the wrist or knees.

See also the related poll result: '3rd party coils are better than the original manufacturer coils'
 
Images, Movies, Sliders:
 Brain MRI Images T1  Open this link in a new window
 Anatomic MRI of the Knee 1  Open this link in a new window
    
SlidersSliders Overview

 MRI of the Brain Stem with Temoral Bone and Auditory System  Open this link in a new window
    
SlidersSliders Overview

 
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• View the DATABASE results for 'Bird Cage Coil' (4).Open this link in a new window

 
Further Reading:
  Basics:
HEAD AND NECK MRI GRADIENT COIL DESIGN
Thursday, 26 August 1999   by www.imaging.robarts.ca    
System Architecture
2003   by www.revisemri.com    
  News & More:
On the Horizon - Next Generation MRI
Wednesday, 23 October 2013   by thefutureofthings.com    
TOSHIBA INTRODUCES 32 ELEMENT COILS FOR ITS VANTAGE TITAN MR SYSTEMS
Tuesday, 9 November 2010   by medical.toshiba.com    
Searchterm 'Radio Frequency' was also found in the following service: 
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Radiology  (2) Open this link in a new window
CoilForum -
related threadsInfoSheet: - Coils - 
Intro, 
Overview, 
etc.MRI Resource Directory:
 - Coils -
 
A coil consists of one or more loops of conductive wire, looped around the core of the coil. Coils are part of the hardware of MRI machines and are used to create a magnetic field or to detect a changing magnetic field by voltage induced in the wire. A coil is usually a physically small antenna.
The perfect coil produces a uniform magnetic field without significant radiation.
Different types of MRI coils are used in MR systems:
Gradient coils are used to produce controlled variations in the main magnetic field (B0) to provide spatial localization of the signals and to apply reversal pulses in some imaging techniques.
MR imaging radio frequency coils to receive and/or transmit the RF signal.
Shim coils provide auxiliary magnetic fields in order to compensate for inhomogeneities in the main magnetic field of the MRI machine.

See also Gradient Coil, Radio Frequency Coil, Hardware and Coil Loading.

See also the related POLL result: '3rd party coils are better than the original manufacturer coils'
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• View the DATABASE results for 'Coil' (193).Open this link in a new window


• View the NEWS results for 'Coil' (11).Open this link in a new window.
 
Further Reading:
  News & More:
3T MRI-Compatible Small Body Array Gets FDA Nod
Monday, 15 January 2024   by www.diagnosticimaging.com    
High-field MRI Coils – that work, superbly, even at 750 MHz
   by www.dotynmr.com    
New superconducting coil improves MRI performance
Wednesday, 20 July 2016   by www.eurekalert.org    
First European fully superconductive coil reaching a magnetic field of 25 Tesla produced
Wednesday, 8 June 2016   by www.news-medical.net    
ScanMed Introduces a Groundbreaking New Orbit and Mandible Array to the MRI Market
Wednesday, 26 March 2014   by www.digitaljournal.com    
MRI coil optimized for imaging of infants gets FDA clearance
Tuesday, 17 April 2012   by www.medcitynews.com    
Low-profile MRI coil company inching toward commercialization
Wednesday, 21 December 2011   by www.medcitynews.com    
High-Resolution Uniform MR Imaging of Finger Joints Using a Dedicated RF Coil at 3 Tesla
Sunday, 31 January 2010   by www.ncbi.nlm.nih.gov    
DOTmed Industry Sector Report: MRI Coil Sales & Service Companies
Thursday, 13 December 2007   by www.dotmed.com    
MRI Resources 
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