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 'T1 Weighted' 
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Result : Searchterm 'T1 Weighted' found in 3 terms [] and 53 definitions []
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Searchterm 'T1 Weighted' was also found in the following services: 
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Relaxation Effect
 
The relaxation effect is the transition of an atom or molecule from a higher energy level to a lower one. The return of the excited proton from the high energy to the low energy level is associated with the loss of energy to the surrounding tissue. The T1 and T2 relaxation times define the way that the protons return to their resting levels after the initial radio frequency (RF) pulse. The T1 and T2 relaxation rates have an effect of the signal to noise ratio (SNR) of MR images.
The relaxation process is a result of both T1 and T2, and can be controlled by the dependency of one of the two biological parameters T1 and T2 in the recorded signal. A T1 weighted spin echo sequence is based on a short repetition time (TR) and a change of it will affect the acquisition time and the T1 weighting of the image. Increased TR results in improved SNR caused by longer recovering time for the longitudinal magnetization. Increased TE improves the T2 weighting, combined with a long TR (of several T1 times) to minimize the T1 effect.
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Further Reading:
  News & More:
MRI's inside story
Thursday, 4 December 2003   by www.economist.com    
MRI Resources 
Journals - MRI Technician and Technologist Career - Contrast Agents - Mobile MRI Rental - Calculation - Breast MRI
 
Resovist®InfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.MRI Resource Directory:
 - Contrast Agents -
 
Resovist® is an organ-specific MRI contrast agent, used for the detection and characterization of especially small focal liver lesions.
Resovist® consists of superparamagnetic iron oxide (SPIO) nanoparticles coated with carboxydextran, which are accumulated by phagocytosis in cells of the reticuloendothelial system (RES) of the liver. The uptake of Resovist® Injection in the reticuloendothelial cells results in a decrease of the signal intensity of normal liver parenchyma on both T2- and T1 weighted images.
Most malignant liver tumors do not contain RES cells and therefore do not uptake the iron particles. The resulting imaging effect is an improved contrast between the tumor (bright) and the surrounding tissue (dark).
Resovist® can be injected as an intravenous bolus, which allows immediate imaging of the liver and reduces the overall examination time. A dynamic imaging strategy after bolus injection supports to characterize lesions. In comprehensive clinical trials, it demonstrated an excellent safety profile.
In 2001, Resovist® was approved for the European market.
See also Superparamagnetic Iron Oxide.

Resovist® competed with Primovist™, the other liver imaging agent of Bayer Schering Pharma AG. Due to this reason, the production of Resovist® has been abandoned in 2009.

Drug Information and Specification
NAME OF COMPOUND Ferrixan [Ferucarbotran], carboxydextran coated iron oxide nanoparticles
DEVELOPER Bayer Schering Pharma AG
CENTRAL MOIETY Fe2+
CONTRAST EFFECT T2/T1, Predominantly negative enhancement
RELAXIVITY r1=25.4, r2=151,
PHARMACOKINETIC RES-directed
OSMOLALITY 333 mosm/kg
CONCENTRATION 0.5 mol Fe/L
DOSAGE Less than 60 kg = 0.9 ml, greater than 60 kg = 1.4 ml
PREPARATION Finished product
INDICATION Liver lesions
DISTRIBUTOR See below
PRESENTATION Pre-filled syringes of 0.9 and 1.4 mL
DO NOT RELY ON THE INFORMATION PROVIDED HERE, THEY ARE NOT A SUBSTITUTE FOR THE ACCOMPANYING PACKAGE INSERT

Distribution Information
TERRITORY TRADE NAME DEVELOPMENT
STAGE
DISTRIBUTOR
USA Resovist® ? -
Japan Resovist® approved -
EU Resovist® approved -
Australia Resovist® Approved -

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Further Reading:
  News & More:
Optimized Labelling of Human Monocytes with Iron Oxide MR Contrast Agents
Sunday, 30 November 2003   by rsna2003.rsna.org    
MRI Resources 
Mobile MRI Rental - DICOM - Musculoskeletal and Joint MRI - Collections - Supplies - Services and Supplies
 
SHU 555 CInfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.
 
Short name: SHU 555 C, preliminary trade name: Supravist™, concentration: 0.5 mol Fe/L
SHU 555 C (Bayer Schering Pharma AG), a contrast agent under development for MRA, is an optimized formulation with respect to T1 weighted MRI of the carboxydextran-coated ferucarbotran (see also Resovist® formerly SHU 555 A, Bayer Schering Pharma AG).
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Searchterm 'T1 Weighted' was also found in the following services: 
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Short T1-Relaxation Gastrointestinal AgentsInfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.
 
Protons in -CH2- groups, e.g., contained in fatty emulsions, mineral or vegetable oil or sucrose polyester, have a fast relaxation and short T1 time. These agents with short T1-relaxation, if used in gastrointestinal imaging, produce bright signal intensities in the intestine on T1 weighted sequences. Palatable oil emulsions can produce appropriate contrast opacification of the stomach as well as the small bowel, but caused by absorption in the distal small bowel these materials are not suitable for use in MRI colonoscopy.
See also Positive Oral Contrast Agents and Gastrointestinal Paramagnetic Contrast Agents.
 
Images, Movies, Sliders:
 MR Colonography Gadolinium per Rectum  Open this link in a new window
      

Courtesy of  Robert R. Edelman
 
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MRI Resources 
Sequences - Cardiovascular Imaging - Implant and Prosthesis - Education - Stent - Pediatric and Fetal MRI
 
Signal Intensity
 
Signal intensity interpretation in MR imaging has a major problem.
Often there is no intuitive approach to signal behavior as signal intensity is a very complicated function of the contrast-determining tissue parameter, proton density, T1 and T2, and the machine parameters TR and TE. For this reason, the terms T1 weighted image, T2 weighted image and proton density weighted image were introduced into clinical MR imaging.
Air and bone produce low-intensity, weaker signals with darker images. Fat and marrow produce high-intensity signals with brighter images.
The signal intensity measured is related to the square of the xy-magnetization, which in a SE pulse sequence is given by
Mxy = Mxy0(1-exp(-TR/T1)) exp(-TE/T2) (1)
where Mxy0 = Mz0 is proportional to the proton or spin density, and corresponds to the z-magnetization present at zero time of the experiment when it is tilted into the xy-plane.
See also T2 Weighted Image and Ernst Angle.
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Further Reading:
  Basics:
Contrast mechanisms in magnetic resonance imaging
2004   by www.iop.org    
Image Characteristics and Quality
   by www.sprawls.org    
  News & More:
Kidney stone imaging with 3D ultra-short echo time (UTE) magnetic resonance imaging. A phantom study - Abstract
Wednesday, 11 March 2015   by www.urotoday.com    
High-Field MRI Superior for Delineation of Alar Ligaments
Friday, 13 April 2012   by www.jaapa.com    
MRI Resources 
Stimulator pool - Examinations - Movies - Services and Supplies - Cochlear Implant - Knee MRI
 
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