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Result : Searchterm 'Magnetic Resonance' found in 21 terms [] and 109 definitions []
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Searchterm 'Magnetic Resonance' was also found in the following services: 
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News  (787)  Resources  (181)  Forum  (1)  
 
Moving Bed Magnetic Resonance AngiographyMRI Resource Directory:
 - MRA -
 
For a contrast enhanced MR angiography of the peripheral blood vessels, the patient reclines on a moveable table that moves under the MR machine to provide images of the abdomen, upper and lower legs in one procedure. A time optimized 3D gradient echo protocol with contrast agent and tabletop movement in several stages is used.
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Searchterm 'Magnetic Resonance' was also found in the following services: 
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Radiology  (14) Open this link in a new windowUltrasound  (27) Open this link in a new window
Rapid Excitation Magnetic Resonance ImagingInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.MRI Resource Directory:
 - Sequences -
 
(RE MRI) There are several approaches to speeding up the MRI data acquisition process by repeating the excitation by RF pulses in times short compared to T1, typically using small flip angles and gradient echo refocusing. When TR is also on the order of or shorter than T2, the repeated RF pulses will tend to refocus transverse magnetization remaining from prior excitations, setting up a condition of steady state free precession, and a dependence of signal strength (and image contrast) on both T1 and T2.
This can be modified in various ways, particularly:
1) to spoil the tendency to build up a steady state by reducing coherence between excitations, e.g. by variation of the phase or timing of consecutive RF pulses or of the strength of spoiler gradient pulses, thus increasing the relative dependence of signal strength on T1 or
2) acquire the signal when it is refocusing immediately prior to the next RF pulse, thus increasing the relative dependence of signal strength on T2.

See also Ultrafast Gradient Echo Sequence.
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• View the DATABASE results for 'Rapid Excitation Magnetic Resonance Imaging' (2).Open this link in a new window

MRI Resources 
Veterinary MRI - Education - General - Case Studies - Fluorescence - Software
 
3 Dimensional Magnetic Resonance AngiographyInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.MRI Resource Directory:
 - MRA -
 
(3D MRA) The 3D angiography technique can be applied to focus on fast flowing (arterial) blood and to visualize small tortuous vessels. 3D TOF images are less sensitive to turbulent flow artifacts. The advantage of this approach is that the signal, acquired from the entire volume has an increased signal to noise ratio. Slices are defined by a second phase encoded axis, which divides the volume into 'partitions'. 3D TOF MRA is acquired with 3D FT slabs or multiple overlapping thin 3D FT slabs (MOTSA) depending on the coverage required and the range of flow-velocities under examination.
Such 3D techniques can provide equal spatial resolution along all three axes, i.e. be 'isotropic', or the partition thickness can be greater or less than the in plane spatial resolution in which case can be said to be 'anisotropic'. The circle of Willis, anatomy as well as its fast arterial flow, lends itself well to both 3D TOF and 2D or 3D phase contrast angiography.
 
Images, Movies, Sliders:
 CE MRA of the Aorta  Open this link in a new window
    
SlidersSliders Overview

 PCA-MRA 3D Brain Venography Colored MIP  Open this link in a new window
    

 CE-MRA of the Carotid Arteries Colored MIP  Open this link in a new window
    
SlidersSliders Overview

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

 
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• View the DATABASE results for '3 Dimensional Magnetic Resonance Angiography' (2).Open this link in a new window

 
Further Reading:
  Basics:
CHAPTER 55: Ischemia
2003
Magnetic resonance angiography: current status and future directions
Wednesday, 9 March 2011   by www.jcmr-online.com    
Searchterm 'Magnetic Resonance' was also found in the following services: 
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News  (787)  Resources  (181)  Forum  (1)  
 
Magnetic Resonance CholangiopancreaticographyMRI Resource Directory:
 - MRCP -
 
(MRCP) This MR imaging technique takes advantage of the high signal intensity of body fluids and acquires heavy T2 weighted images of the gall bladder, the pancreas and parts of the liver. Due to the T2 weighting, the liver and other solid parenchyma are signal suppressed and only fluid-filled structures in addition to the gall bladder, the bile and pancreatic ducts retain important signal intensity. Hepatobiliary contrast agents (e.g. Gadoxetic Acid, CMC 001) can be useful for enhancement of the bile ducts and better imaging of the biliary tract.
A 2D cholangiogram, often only one thick slice (a volume with a thickness of 4 - 8 cm, mostly coronal planned) or 5 - 6 radial placed slices, shows a view like single slices. If a 3D acquisition is used, the postprocessing function maximum intensity projection (MIP) can show reconstructions from multiple sides.
Radiology-tip.comradBiliary Contrast Agents
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Medical-Ultrasound-Imaging.comGallbladder Ultrasound
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• View the DATABASE results for 'Magnetic Resonance Cholangiopancreaticography' (3).Open this link in a new window

 
Further Reading:
  News & More:
Perspectum and Nuance Collaborate to Scale Access to AI-Enabled Integrated Digital Care Platforms to Improve Patient Care for Metabolic Disease
Friday, 9 December 2022   by www.itnonline.com    
Searchterm 'Magnetic Resonance' was also found in the following services: 
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Radiology  (14) Open this link in a new windowUltrasound  (27) Open this link in a new window
Contrast Enhanced Magnetic Resonance AngiographyInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.MRI Resource Directory:
 - MRA -
 
(CE MRA) Contrast enhanced MR angiography is based on the T1 values of blood, the surrounding tissue, and paramagnetic contrast agent.
T1-shortening contrast agents reduces the T1 value of the blood (approximately to 50 msec, shorter than that of the surrounding tissues) and allow the visualization of blood vessels, as the images are no longer dependent primarily on the inflow effect of the blood. Contrast enhanced MRA is performed with a short TR to have low signal (due to the longer T1) from the stationary tissue, short scan time to facilitate breath hold imaging, short TE to minimize T2* effects and a bolus injection of a sufficient dose of a gadolinium chelate.
Images of the region of interest are performed with 3D spoiled gradient echo pulse sequences. The enhancement is maximized by timing the contrast agent injection such that the period of maximum arterial concentration corresponds to the k-space acquisition. Different techniques are used to ensure optimal contrast of the arteries e.g., bolus timing, automatic bolus detection, bolus tracking, care bolus. A high resolution with near isotropic voxels and minimal pulsatility and misregistration artifacts should be striven for. The postprocessing with the maximum intensity projection (MIP) enables different views of the 3D data set.
Unlike conventional MRA techniques based on velocity dependent inflow or phase shift techniques, contrast enhanced MRA exploits the gadolinium induced T1-shortening effects. CE MRA reduces or eliminates most of the artifacts of time of flight angiography or phase contrast angiography. Advantages are the possibility of in plane imaging of the blood vessels, which allows to examine large parts in a short time and high resolution scans in one breath hold. CE MRA has found a wide acceptance in the clinical routine, caused by the advantages:
•
3D MRA can be acquired in any plane, which means that greater vessel coverage can be obtained at high resolution with fewer slices (aorta, peripheral vessels);
•
the possibility to perform a time resolved examination (similarly to conventional angiography);
•
no use of ionizing radiation; paramagnetic agents have a beneficial safety.
 
Images, Movies, Sliders:
 CE-MRA of the Carotid Arteries  Open this link in a new window
    
SlidersSliders Overview

 CE MRA of the Aorta  Open this link in a new window
    
SlidersSliders Overview

 CE-MRA of the Carotid Arteries Colored MIP  Open this link in a new window
    
SlidersSliders Overview

 
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• View the DATABASE results for 'Contrast Enhanced Magnetic Resonance Angiography' (14).Open this link in a new window


• View the NEWS results for 'Contrast Enhanced Magnetic Resonance Angiography' (2).Open this link in a new window.
 
Further Reading:
  Basics:
Contrast-Enhanced MR Angiography(.pdf)
   by ric.uthscsa.edu    
CONTRAST ENHANCED MR ANGIOGRAPHY – PRINCIPLES, APPLICATIONS, TIPS AND PITFALLS(.pdf)
  News & More:
CONTRAST-ENHANCED MRA OF THE CAROTIDS(.pdf)
PERIPHERAL VASCULAR MAGNETIC RESONANCE ANGIOGRAPHY(.pdf)
CONTRAST ENHANCED MRI OF THE LIVER STATE-OF-THE-ART(.pdf)
MRI Resources 
Shoulder MRI - Sequences - Stent - Mass Spectrometry - Process Analysis - Chemistry
 
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