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Result : Searchterm 'Spectroscopy' found in 12 terms [] and 83 definitions []
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Searchterm 'Spectroscopy' was also found in the following services: 
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News  (16)  Resources  (59)  Forum  (3)  
 
MRI History
 
•
Sir Joseph Larmor (1857-1942) developed the equation that the angular frequency of precession of the nuclear spins being proportional to the strength of the magnetic field. [Larmor relationship]
•
In the 1930's, Isidor Isaac Rabi (Columbia University) succeeded in detecting and measuring single states of rotation of atoms and molecules, and in determining the mechanical and magnetic moments of the nuclei.
•
Felix Bloch (Stanford University) and Edward Purcell (Harvard University) developed instruments, which could measure the magnetic resonance in bulk material such as liquids and solids. (Both honored with the Nobel Prize for Physics in 1952.) [The birth of the NMR spectroscopy]
•
In the early 70's, Raymond Damadian (State University of New York) demonstrated with his NMR device, that there are different T1 relaxation times between normal and abnormal tissues of the same type, as well as between different types of normal tissues.
•
In 1973, Paul Lauterbur (State University of New York) described a new imaging technique that he termed Zeugmatography. By utilizing gradients in the magnetic field, this technique was able to produce a two-dimensional image (back-projection). (Through analysis of the characteristics of the emitted radio waves, their origin could be determined.) Peter Mansfield further developed the utilization of gradients in the magnetic field and the mathematically analysis of these signals for a more useful imaging technique. (Paul C Lauterbur and Peter Mansfield were awarded with the 2003 Nobel Prize in Medicine.)
•
In 1975, Richard Ernst introduced 2D NMR using phase and frequency encoding, and the Fourier Transform. Instead of Paul Lauterbur's back-projection, he timely switched magnetic field gradients ('NMR Fourier Zeugmatography'). [This basic reconstruction method is the basis of current MRI techniques.]
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1977/78: First images could be presented. A cross section through a finger by Peter Mansfield and Andrew A. Maudsley. Peter Mansfield also could present the first image through the abdomen.
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In 1977, Raymond Damadian completed (after 7 years) the first MR scanner (Indomitable). In 1978, he founded the FONAR Corporation, which manufactured the first commercial MRI scanner in 1980. Fonar went public in 1981.
•
1981: Schering submitted a patent application for Gd-DTPA dimeglumine.
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1982: The first 'magnetization-transfer' imaging by Robert N. Muller.
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In 1983, Toshiba obtained approval from the Ministry of Health and Welfare in Japan for the first commercial MRI system.
•
In 1984, FONAR Corporation receives FDA approval for its first MRI scanner.
•
1986: Jürgen Hennig, A. Nauerth, and Hartmut Friedburg (University of Freiburg) introduced RARE (rapid acquisition with relaxation enhancement) imaging. Axel Haase, Jens Frahm, Dieter Matthaei, Wolfgang Haenicke, and Dietmar K. Merboldt (Max-Planck-Institute, Göttingen) developed the FLASH (fast low angle shot) sequence.
•
1988: Schering's MAGNEVIST gets its first approval by the FDA.
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In 1991, fMRI was developed independently by the University of Minnesota's Center for Magnetic Resonance Research (CMRR) and Massachusetts General Hospital's (MGH) MR Center.
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From 1992 to 1997 Fonar was paid for the infringement of it's patents from 'nearly every one of its competitors in the MRI industry including giant multi-nationals as Toshiba, Siemens, Shimadzu, Philips and GE'.
•
 
Images, Movies, Sliders:
 Cardiac Infarct Short Axis Cine Overview  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 
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• Related Searches:
    • Medical Imaging
    • Cardiac MRI
    • Open MRI
    • Lumbar Spine MRI
    • Spin
 
Further Reading:
  Basics:
Magnetic Resonance Imaging, History & Introduction
2000   by www.cis.rit.edu    
A Short History of the Magnetic Resonance Imaging (MRI)
   by www.teslasociety.com    
Fonar Our History
   by www.fonar.com    
  News & More:
Scientists win Nobels for work on MRI
Tuesday, 10 June 2003   by usatoday30.usatoday.com    
2001 Lemelson-MIT Lifetime Achievement Award Winner
   by web.mit.edu    
MRI's inside story
Thursday, 4 December 2003   by www.economist.com    
Searchterm 'Spectroscopy' was also found in the following service: 
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Radiology  (1) Open this link in a new window
MRP-7000â„¢InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.hitachimed.com/products/mrp.asp From Hitachi Medical Systems America, Inc.;
because of its dependability, the MRP-7000â„¢ remains popular more than a decade after the first U.S. system was shipped. This system maintains a high resale value, what has made it one of the most sought-after scanners on the used MRI equipment market.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Vertical Orientation Field
DualQuad T/R Body Coil, MA Head, MA C-Spine, MA Shoulder, MA Wrist, MA CTL Spine, MA Knee, MA TMJ, MA Flex Body (3 sizes), Neck, small and large Extremity, PVA (WIP), Breast (WIP), Neurovascular (WIP), Cardiac (WIP) and MA Foot//Ankle (WIP)
SYNCHRONIZATION
Cardiac gating, ECG/peripheral, respiratory gating (2 modes)
PULSE SEQUENCES
SE, GE, GR, IR, FIR, STIR, ss-FSE, FSE, DE-FSE/FIR, FLAIR, ss/ms-EPI, ss/ms EPI- DWI, SSP, MTC, SE/GE-EPI, MRCP, SARGE, RSSG, TRSG, BASG, Angiography: CE, PC, 2D/3D TOF
IMAGING MODES
Single, multislice, volume study
MAGNET TYPE
Permanent, self shielded
STRENGTH
8 mT/m
5-GAUSS FRINGE FIELD
horizontal 2.5 m x 2.1 m vertical
Auto shimming, 3-axis/patient and active shimming
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• View the DATABASE results for 'MRP-7000™' (2).Open this link in a new window

MRI Resources 
Nerve Stimulator - Non-English - Artifacts - Brain MRI - MRI Technician and Technologist Schools - Blood Flow Imaging
 
MSK-Extremeâ„¢InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.onicorp.com/ From ONI Medical Systems, Inc.;
MSK-Extremeâ„¢MRI system is a dedicated high field extremity imaging device, designed to provide orthopedic surgeons and other physicians with detailed diagnostic images of the foot, ankle, knee, hand, wrist and elbow, all with the clinical confidence and advantages derived from high field, whole body MRI units. The light weight (less than 650 kg) of the OrthOne System performs rapid patient studies, is easy to operate, has a patient friendly open environment and can be installed in a practice office or hospital, all at a cost similar to a low field extremity machine.
New features include a more powerful operating system that offers increased scan speed as well as a 160-mm knee coil with higher signal to noise ratio, and the option of a CD burner.
Device Information and Specification
CLINICAL APPLICATION
Dedicated extremity imaging
CONFIGURATION
16 cm knee, 18 cm lower extremity;; 12.3 cm upper extremity, additional high resolution v-SPEC Coils: 80 mm, 100 mm, or 145 mm.
SYNCHRONIZATION
No
PULSE SEQUENCES
SE, FSE, GE2D, GE3D, Inversion recovery (IR), Driven Equilibrium, Fat Saturation (FS), STIR, MT, PD, Flow Compensation (FC), RF spoiling, MTE, No Phase Wrap (NPW)
IMAGING MODES
Scout, single, multislice, volume
TR
10-10,000ms; 1ms steps
TE
5-150ms; 1 ms steps
SINGLE/MULTI SLICE
2D less than 200 msec/image
4cm-16cm
2D: 2mm-10mm/.1mm incr.
Up to 1,000x1,000
MEASURING MATRIX
X/Y: 64-512; 2 pixel steps
PIXEL INTENSITY
4,096 grey lvls; 256 lvls in 3D
28cm ID x 50cm L
MAGNET WEIGHT
635 kg
H*W*D
146 x 69 x 84 cm
POWER REQUIREMENTS
115VAC, 1phase, 20A; 208VAC, 3 phase, 30A
COOLING SYSTEM TYPE
LHe with 2 stage cold head
Negligible
STRENGTH
15 mT/m
5-GAUSS FRINGE FIELD
1.25m radial x 1.8m axial
Passive
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Further Reading:
  Basics:
MSK Extreme Brochure(.pdf)
   by www.nova-logic.ch    
MSK Extreme Specifications(.pdf)
   by www.nova-logic.ch    
Searchterm 'Spectroscopy' was also found in the following services: 
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News  (16)  Resources  (59)  Forum  (3)  
 
Magic Angle Effect (Artifact)InfoSheet: - Artifacts - 
Case Studies, 
Reduction Index, 
etc.MRI Resource Directory:
 - Artifacts -
 
Quick Overview
Artifact Information
NAME
Magic angle
DESCRIPTION
Increase of the T2 time, bright signal in tendons
REASON
Angle about 55° to the main magnetic field
HELP
Angle not about 55°
The magic angle is a precisely defined angle, the value is approximately 54.7°. Hence, two nuclei with a dipolar coupling vector at an angle of approximately 54.7° to a strong external magnetic field have zero dipolar coupling.
Magic angle spinning is a technique in solid-state NMR spectroscopy, which employs this principle to remove or reduce dipolar couplings, thereby increasing spectral resolution. In MRI, the magic angle effect visualizes as bright spots through an increased T2 time on short echo time (TE) images, for e.g. collagen fibers of tendons and ligaments, which are oriented at the magic angle of approximately 54.7° to the magnetic field.
mri safety guidance
Image Guidance
Take care that tendons and ligaments are not oriented at about a 54.7° angle to the main magnetic field.
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Further Reading:
  Basics:
Magic angle
   by en.wikipedia.org    
Magic Angle Effects
   by www.mritutor.org    
Searchterm 'Spectroscopy' was also found in the following service: 
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Radiology  (1) Open this link in a new window
Magnitude Calculation
 
Magnitude calculation e.g. cuts the amplitude information, or can be used to obtain pure absorption Lorentzian lineshapes in spectroscopy.
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MRI Resources 
Databases - Raman Spectroscopy - Artifacts - Chemistry - Calculation - Safety Products
 
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