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Result : Searchterm 'Contrast Resolution' found in 1 term [] and 5 definitions [], (+ 19 Boolean[] results
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Searchterm 'Contrast Resolution' was also found in the following services: 
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News  (7)  
 
Lumbar Spine MRI
 
MRI of the lumbar spine, with its multiplanar 3 dimensional imaging capability, is currently the preferred modality for establishing a diagnosis. MRI scans and magnetic resonance myelography have many advantages compared with computed tomography and/or X-ray myelography in evaluating the lumbar spine. MR imaging scans large areas of the spine without ionizing radiation, is noninvasive, not affected by bone artifacts, provides vascular imaging capability, and makes use of safer contrast agents (gadolinium chelate).
Due to the high level of tissue contrast resolution, nerves and discs are clearly visible. MRI is excellent for detecting degenerative disease in the spine. Lumbar spine MRI accurately shows disc disease (prolapsed disc or slipped disc), the level at which disc disease occurs, and if a disc is compressing spinal nerves. Lumbar spine MRI depicts soft tissues, including the cauda equina, spinal cord, ligaments, epidural fat, subarachnoid space, and intervertebral discs. Loss of epidural fat on T1 weighted images, loss of cerebrospinal fluid signal around the dural sac on T2 weighted images and degenerative disc disease are common features of lumbar stenosis.

Common indications for MRI of the lumbar spine:
Neurologic deficits, evidence of radiculopathy, acute spinal cord compression (e.g., sudden bowel/bladder disturbance)
Suspected systemic disorders (primary tumors, drop metastases, osteomyelitis)
Postoperative evaluation of lumbar spine: disk vs. scar
Localized back pain with no radiculopathy (leg pain)

Lumbar spine imaging requires a special spine coil. often used whole spine array coils have the advantage that patients do not need other positioning if also upper parts of the spine should be scanned. Sagittal T1 and T2 weighted FSE sequences are the standard views. With multi angle oblique techniques individually oriented transverse images of each intervertebral disc at different angles can be obtained.

See also the related poll result: 'MRI will have replaced 50% of x-ray exams by'
 
Images, Movies, Sliders:
 Anatomic Imaging of the Lumbar Spine  Open this link in a new window
      

Courtesy of  Robert R. Edelman

 
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• Related Searches:
    • Multiplanar Reconstruction
    • Crosstalk (Artifact)
    • Contrast Agents
    • Multi Angle Oblique
    • Cerebro Spinal Fluid Pulsation Artifact
 
Further Reading:
  Basics:
Lumbar Spine Stenosis: A Common Cause of Back and Leg Pain
   by www.aafp.org    
Spine imaging after lumbar disc replacement: pitfalls and current recommendations
Tuesday, 21 July 2009   by 7thspace.com    
  News & More:
Impact of patient-reported symptom information on lumbar spine MRI Interpretation
Monday, 25 January 2021   by www.eurekalert.org    
Lumbar spine MRI reports are too difficult for patients to understand
Friday, 29 March 2019   by www.eurekalert.org    
Inappropriate Ordering of Lumbar Spine Magnetic Resonance Imaging: Are Providers Choosing Wisely? -
Tuesday, 2 February 2016   by www.ajmc.com    
How Weight-Bearing MRIs Can Improve Care & Lower Costs While Meeting Milliman Criteria
Friday, 4 October 2013   by www.beckersspine.com    
Lumbar Diskal Cyst Containing Intervertebral Disk Materials
Tuesday, 1 November 2011   by www.orthosupersite.com    
A Study of the Morphology of Lumbar Discs in Sitting and Standing Positions Using a 0.5T Open- Configuration MRI(.pdf)
2001   by cds.ismrm.org    
Searchterm 'Contrast Resolution' was also found in the following services: 
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Radiology  (1) Open this link in a new windowUltrasound  (1) Open this link in a new window
EPIX Pharmaceuticals, Inc.MRI Resource Directory:
 - Developers -
 
www.epixmed.com [This entry is marked for removal.]

(July 20, 2009 - EPIX Pharmaceuticals, Inc. announced today that, in light of the company's lack of capital and inability to obtain additional financing or consummate a strategic transaction, it has entered into an Assignment for the Benefit of Creditors, effective immediately, in accordance with Massachusetts law).
EPIX has been a specialty pharmaceutical firm developing targeted contrast agents to improve the capability of MRI as a diagnostic tool for a variety of diseases. Gadofosveset trisodium (formerly MS-325, Vasovistâ„¢, now ABLAVARtâ„¢), is an injectable intravascular contrast agents designed for multiple vascular imaging applications, including peripheral vascular disease and coronary artery disease. EPIX conducted a pivotal Phase III trial for the detection of peripheral vascular disease, as well as a Phase II feasibility trial for coronary artery disease diagnosis.
To ensure rapid development and adoption of gadofosveset trisodium into clinical practice upon regulatory approval, EPIX pursued an aggressive product development plan and commercialization strategy. The Company established an exclusive, worldwide sales and marketing agreement with Bayer Schering Pharma AG. EPIX also established corporate collaborations with GE Healthcare, Philips Medical Systems and Siemens Medical Systems, the three leading MRI manufacturers, which together account for approximately 80 percent of the MRI machines installed worldwide.
EPIX had other MRI contrast agents under development, most significantly a novel prototype blood clot agent (EP-2104R). Potential clinical applications for this type of agent include detection of deep venous thrombosis, pulmonary embolism and blood clots in the coronary and carotid arteries. Currently, there is no high resolution imaging technique to directly visualize blood clots in patients with suspected cardiovascular disease.
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• View the DATABASE results for 'EPIX Pharmaceuticals, Inc.' (7).Open this link in a new window


• View the NEWS results for 'EPIX Pharmaceuticals, Inc.' (69).Open this link in a new window.
 
Further Reading:
  Basics:
Epix Pharmaceuticals to shut down
Tuesday, 21 July 2009   by boston.bizjournals.com    
MRI Resources 
Knee MRI - MRA - Spectroscopy pool - Liver Imaging - Universities - Education
 
Intera Achieva 1.5Tâ„¢InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.medical.philips.com/main/products/mri/products/intera_achieva/ From Philips Medical Systems;
The clinical capabilities of MR will further expand. Inside and out, the Achieva is a friendly, open system designed for optimal patient comfort and maximized workflow with high functionality. The Achieva 1.5T can be upgraded to Achieva I/T, with three configurations optimized for MR guided interventions and therapy:
Achieva I/T
Achieva I/T Neurosurgery
Achieva I/T Cardiovascular (or XMR - combining an Achieva 1.5T CV system and an X-Ray system)
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Short bore compact
Standard: Head, body, C1, C3; Optional: Small joint, flex-E, flex-R, endocavitary (L and S), dual TMJ, knee, neck, T/L spine, breast; optional phased array: Spine, pediatric, 3rd party connector; Optional SENSEâ„¢ coils for all applications
Optional
SYNCHRONIZATION
ECG/peripheral: Optional/yes, respiratory gating
PULSE SEQUENCES
SE, Modified-SE, IR (T1, T2, PD), STIR, FLAIR, SPIR, FFE, T1-FFE, T2-FFE, Balanced FFE, TFE, Balanced TFE, Dynamic, Keyhole, 3D, Multi Chunk 3D, Multi Stack 3D, K Space Shutter, MTC, TSE, Dual IR, DRIVE, EPI, Cine, 2DMSS, DAVE, Mixed Mode; Angiography: Inflow MRA, TONE, PCA, CE MRA
IMAGING MODES
Single Slice 2D , Multi Single Slice 2D, Multi Slice 2D, 3D, Multi Chunk 3D, Multi Stack 3D
FOV
Over 40 cm
0.05 mm
128 x 128, 256 x 256,512 x 512,1024 x 1024 (64 for Bold img)
MEASURING MATRIX
Variable in 1% increments
PIXEL INTENSITY
Lum.: 120 cd/m2; contrast: 150:1
Variable (op. param. depend.)
60 x 60 cm
POWER REQUIREMENTS
380/400 V
CRYOGEN USE
0.03 L/hr helium
STRENGTH
up to 66 mT/m
5-GAUSS FRINGE FIELD
2.4 m / 3.8 m
Passive and dynamic
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• View the DATABASE results for 'Intera Achieva 1.5T™' (2).Open this link in a new window

Searchterm 'Contrast Resolution' was also found in the following services: 
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News  (7)  
 
Fast Spin EchoForum -
related threadsInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
Fast Spin Echo Diagram (FSE) In the pulse sequence timing diagram, a fast spin echo sequence with an echo train length of 3 is illustrated. This sequence is characterized by a series of rapidly applied 180° rephasing pulses and multiple echoes, changing the phase encoding gradient for each echo.
The echo time TE may vary from echo to echo in the echo train. The echoes in the center of the K-space (in the case of linear k-space acquisition) mainly produce the type of image contrast, whereas the periphery of K-space determines the spatial resolution. For example, in the middle of K-space the late echoes of T2 weighted images are encoded. T1 or PD contrast is produced from the early echoes.
The benefit of this technique is that the scan duration with, e.g. a turbo spin echo turbo factor / echo train length of 9, is one ninth of the time. In T1 weighted and proton density weighted sequences, there is a limit to how large the ETL can be (e.g. a usual ETL for T1 weighted images is between 3 and 7). The use of large echo train lengths with short TE results in blurring and loss of contrast. For this reason, T2 weighted imaging profits most from this technique.
In T2 weighted FSE images, both water and fat are hyperintense. This is because the succession of 180° RF pulses reduces the spin spin interactions in fat and increases its T2 decay time. Fast spin echo (FSE) sequences have replaced conventional T2 weighted spin echo sequences for most clinical applications. Fast spin echo allows reduced acquisition times and enables T2 weighted breath hold imaging, e.g. for applications in the upper abdomen.
In case of the acquisition of 2 echoes this type of a sequence is named double fast spin echo / dual echo sequence, the first echo is usually density and the second echo is T2 weighted image. Fast spin echo images are more T2 weighted, which makes it difficult to obtain true proton density weighted images. For dual echo imaging with density weighting, the TR should be kept between 2000 - 2400 msec with a short ETL (e.g., 4).
Other terms for this technique are:
Turbo Spin Echo
Rapid Imaging Spin Echo,
Rapid Spin Echo,
Rapid Acquisition Spin Echo,
Rapid Acquisition with Refocused Echoes
 
Images, Movies, Sliders:
 Lumbar Spine T2 FSE Sagittal  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 MRI - Anatomic Imaging of the Foot  Open this link in a new window
    
SlidersSliders Overview

 Lumbar Spine T2 FSE Axial  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 
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• View the DATABASE results for 'Fast Spin Echo' (31).Open this link in a new window

 
Further Reading:
  Basics:
MYELIN-SELECTIVE MRI: PULSE SEQUENCE DESIGN AND OPTIMIZATION
   by www.imaging.robarts.ca    
Advances in Magnetic Resonance Neuroimaging
Friday, 27 February 2009   by www.ncbi.nlm.nih.gov    
  News & More:
New MR sequence helps radiologists more accurately evaluate abnormalities of the uterus and ovaries
Thursday, 23 April 2009   by www.eurekalert.org    
Spin echoes, CPMG and T2 relaxation - Introductory NMR & MRI from Magritek
2013   by www.azom.com    
Searchterm 'Contrast Resolution' was also found in the following services: 
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Radiology  (1) Open this link in a new windowUltrasound  (1) Open this link in a new window
Signa 3.0Tâ„¢InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.gehealthcare.com/usen/mr/s_excite3/index.html (Signa VH/i 3.0T)
With GE Healthcare leading-edge technology in ultra-high-field imaging. The 3 T VH/i provides a platform for advanced applications in radiology, cardiology, psychology and psychiatry. Real-time image processing lets you acquire multislice whole brain images and map brain functions for research or surgical planning. And the 3 T Signa VH/i is flexible enough to provide clinicians with high performance they require. It can provide not only outstanding features in brain scanning and neuro-system research, but also a wide range of use in scanning breasts, extremities, the spine and the cardiovascular systems.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Cylindrical - high homogeneity
T/R quadrature head, T/R quadrature body, T/R phased array extremity (opt)
SYNCHRONIZATION
ECG/peripheral, respiratory gating
PULSE SEQUENCES
SE, IR, 2D/3D GRE, FGRE, RF-spoiled GRE, FSE, Angiography: 2D/3D TOF, 2D/3D phase contrast vascular
IMAGING MODES
Single, multislice, volume study, fast scan, multi slab, cine, localizer
SINGLE SLICE
100 Images/sec with Reflex100
MULTISLICE
100 Images/sec with Reflex100
1 cm to 40 cm continuous
2D 0.5-100mm in 0.1mm incremental
1280 x 1024
MEASURING MATRIX
128x512 steps 32 phase encode
PIXEL INTENSITY
256 gray levels
55cm
MAGNET WEIGHT
15102 kg incl. cryogen's
H*W*D
260cm x 238cm x 265cm
POWER REQUIREMENTS
480 or 380/415, 3 phase ||
COOLING SYSTEM TYPE
Closed-loop water-cooled grad.
Less than 0.14 L/hr liquid He
STRENGTH
40mT/m
5-GAUSS FRINGE FIELD, radial/axial
5.4 m x 3.2 m
Superconductive + hi order active
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• View the DATABASE results for 'Signa 3.0T™' (2).Open this link in a new window

MRI Resources 
Functional MRI - MRI Centers - Safety pool - Homepages - Lung Imaging -
 
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