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Searchterm 'Energy' was also found in the following services: 
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DecouplingInfoSheet: - Artifacts - 
Case Studies, 
Reduction Index, 
etc.
 
1) The specific irradiation designed to remove the multiple structure in a particular resonance due to spin spin coupling with other nuclei;
2) The preventing of the interaction by mutual inductive coupling of two (or more) resonant RF coils, e.g. by detuning coils not in use at a particular point in time. Decoupling can take the form of active decoupling where an externally controlled switching circuit is used to detune the non-selected coils or passive decoupling where RF energy from the transmitter pulse is used to switch diodes to detune the appropriate coil.
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Further Reading:
  Basics:
A Half-Volume Coil for Efficient Proton Decoupling in Humans at 4 Tesla
1997   by www.cmrr.umn.edu    
Searchterm 'Energy' was also found in the following services: 
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DeviceForum -
related threadsInfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.
 
Magnetic resonance imaging (MRI) is based on the magnetic resonance phenomenon, and is used for medical diagnostic imaging since ca. 1977 (see also MRI History).
The first developed MRI devices were constructed as long narrow tunnels. In the meantime the magnets became shorter and wider. In addition to this short bore magnet design, open MRI machines were created. MRI machines with open design have commonly either horizontal or vertical opposite installed magnets and obtain more space and air around the patient during the MRI test.
The basic hardware components of all MRI systems are the magnet, producing a stable and very intense magnetic field, the gradient coils, creating a variable field and radio frequency (RF) coils which are used to transmit energy and to encode spatial positioning. A computer controls the MRI scanning operation and processes the information.
The range of used field strengths for medical imaging is from 0.15 to 3 T. The open MRI magnets have usually field strength in the range 0.2 Tesla to 0.35 Tesla. The higher field MRI devices are commonly solenoid with short bore superconducting magnets, which provide homogeneous fields of high stability.
There are this different types of magnets:
The majority of superconductive magnets are based on niobium-titanium (NbTi) alloys, which are very reliable and require extremely uniform fields and extreme stability over time, but require a liquid helium cryogenic system to keep the conductors at approximately 4.2 Kelvin (-268.8° Celsius). To maintain this temperature the magnet is enclosed and cooled by a cryogen containing liquid helium (sometimes also nitrogen).
The gradient coils are required to produce a linear variation in field along one direction, and to have high efficiency, low inductance and low resistance, in order to minimize the current requirements and heat deposition. A Maxwell coil usually produces linear variation in field along the z-axis; in the other two axes it is best done using a saddle coil, such as the Golay coil.
The radio frequency coils used to excite the nuclei fall into two main categories; surface coils and volume coils. The essential element for spatial encoding, the gradient coil sub-system of the MRI scanner is responsible for the encoding of specialized contrast such as flow information, diffusion information, and modulation of magnetization for spatial tagging.
An analog to digital converter turns the nuclear magnetic resonance signal to a digital signal. The digital signal is then sent to an image processor for Fourier transformation and the image of the MRI scan is displayed on a monitor.

For Ultrasound Imaging (USI) see Ultrasound Machine at Medical-Ultrasound-Imaging.com.

See also the related poll results: 'In 2010 your scanner will probably work with a field strength of' and 'Most outages of your scanning system are caused by failure of'
Radiology-tip.comradGamma Camera,  Linear Accelerator
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Medical-Ultrasound-Imaging.comUltrasound Machine,  Real-Time Scanner
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• View the DATABASE results for 'Device' (141).Open this link in a new window


• View the NEWS results for 'Device' (29).Open this link in a new window.
 
Further Reading:
  News & More:
small-steps-can-yield-big-energy-savings-and-cut-emissions-mris
Thursday, 27 April 2023   by www.itnonline.com    
Portable MRI can detect brain abnormalities at bedside
Tuesday, 8 September 2020   by news.yale.edu    
Point-of-Care MRI Secures FDA 510(k) Clearance
Thursday, 30 April 2020   by www.diagnosticimaging.com    
World's First Portable MRI Cleared by FDA
Monday, 17 February 2020   by www.medgadget.com    
Low Power MRI Helps Image Lungs, Brings Costs Down
Thursday, 10 October 2019   by www.medgadget.com    
Cheap, portable scanners could transform brain imaging. But how will scientists deliver the data?
Tuesday, 16 April 2019   by www.sciencemag.org    
The world's strongest MRI machines are pushing human imaging to new limits
Wednesday, 31 October 2018   by www.nature.com    
Kyoto University and Canon reduce cost of MRI scanner to one tenth
Monday, 11 January 2016   by www.electronicsweekly.com    
A transportable MRI machine to speed up the diagnosis and treatment of stroke patients
Wednesday, 22 April 2015   by medicalxpress.com    
Portable 'battlefield MRI' comes out of the lab
Thursday, 30 April 2015   by physicsworld.com    
Chemists develop MRI technique for peeking inside battery-like devices
Friday, 1 August 2014   by www.eurekalert.org    
New devices doubles down to detect and map brain signals
Monday, 23 July 2012   by scienceblog.com    
MRI Resources 
MRI Physics - MRI Accidents - Sequences - Mass Spectrometry - Education pool - NMR
 
DiffusionForum -
related threads
 
The process by which molecules or other particles intermingle and migrate due to their random thermal motion. Microscopic particles are jittering around with translational and rotational motions as a result of their thermal energy, which is half the Boltzmann constant multiplied by the absolute temperature of the system (0.5kT) per degree of freedom (3 directions of translation and 3 directions of rotation for ordinary particles).
MRI provides a sensitive technique for measuring diffusion of some substances. These diffusive processes mean that particles reach areas of low from areas of high concentration, thus leading to equilibration. In body fluids, the distribution of capillaries within tissues is such that transport over macroscopic distances is accomplished by the blood circulation, while over intercapillary distances substances are carried by diffusion. The fluid diffusion constant is itself inversely proportional to the viscosity and the radius of the diffusing particles.

See also Diffusion Tensor Imaging and Diffusion Weighted Imaging.
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• View the NEWS results for 'Diffusion' (12).Open this link in a new window.
 
Further Reading:
  Basics:
Conventional MRI and MR Angiography of Stroke
2012   by www.mc.vanderbilt.edu    
EVALUATION OF HUMAN STROKE BY MR IMAGING
2000
Diffusion-Weighted MRI in the Body: Applications and Challenges in Oncology
Friday, 1 June 2007   by www.ajronline.org    
  News & More:
EORTC study aims to qualify ADC as predictive imaging biomarker in preoperative regimens
Monday, 4 January 2016   by www.eurekalert.org    
Diffusion-weighted MRI sensitive for metastasis in pelvic lymph nodes
Sunday, 15 June 2014   by www.2minutemedicine.com    
Connecting the dots: Water diffusion MRI reveals plasticity networks in remote nonstimulated brain regions
Monday, 31 March 2014   by medicalxpress.com    
Searchterm 'Energy' was also found in the following services: 
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EchoForum -
related threads
 
In MRI, an echo is the emission of energy in form of an electromagnetic resonance signal of a nuclei after its excitation. At this point spins are back in phase again and the signal is measured. The desired number of echoes is selectable. Often until eight echoes are permissible for 2D or 3D scans using spin echo, inversion recovery or MIX techniques. Two echoes are permissible for all other techniques. A multi echo imaging sequence is needed for simultaneous measurement of T2 and density weighted images.
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Further Reading:
  News & More:
Ultrashort echo time (UTE) MRI of the spine in thalassaemia
February 2004   by bjr.birjournals.org    
UCLA chemists use MRI to peek at temperatures of gases inside catalytic reactors
Thursday, 24 October 2013   by esciencenews.com    
Searchterm 'Energy' was also found in the following services: 
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Electromagnetic Spectrum
 
Continuum of electromagnetic energy.
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