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 'Fast Spin Echo' 
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Result : Searchterm 'Fast Spin Echo' found in 5 terms [] and 28 definitions []
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Searchterm 'Fast Spin Echo' was also found in the following service: 
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Forum  (3)  
 
Fat SuppressionForum -
related threads
 
Fat suppression is the process of utilizing specific MRI parameters to remove the deleterious effects of fat from the resulting images , e.g. with STIR, FAT SAT sequences, water selective (PROSET WATS - water only selection, also FATS - fat only selection possible) excitation techniques, or pulse sequences based on the Dixon method.
Spin magnetization can be modulated by using special RF pulses. CHESS or its variations like SPIR, SPAIR (Spectral Selection Attenuated Inversion Recovery) and FAT SAT use frequency selective excitation pulses, which produce fat saturation.
Fat suppression techniques are nearly used in all body parts and belong to every standard MRI protocol of joints like knee, shoulder, hips, etc.
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Image Guidance
Imaging of, e.g. the foot can induce bad fat suppression with SPIR/FAT SAT due to the asymmetric volume of this body part. The volume of the foot alters the magnetic field to a different degree than the smaller volume of the lower leg affecting the protons there. There is only a small band of tissue where the fat protons are precessing at the frequency expected, resulting in frequency selective fat saturation working only in that area. This can be corrected by volume shimming or creating a more symmetrical volume being imaged with water bags.
Even with their longer scan time and motion sensitivity, STIR (short T1/tau inversion recovery) sequences are often the better choice to suppress fat. STIR images are also preferred because of the decreased sensitivity to field inhomogeneities, permitting larger fields of views when compared to fat suppressed images and the ability to image away from the isocenter.
See also Knee MRI.
Sequences based on Dixon turbo spin echo (fast spin echo) can deliver a significant better fat suppression than conventional TSE/FSE imaging.
 
Images, Movies, Sliders:
 Shoulder Axial T2 FatSat FRFSE  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 MRI Orbita T2 FatSat  Open this link in a new window
    
 Knee MRI Sagittal STIR 001  Open this link in a new window
 MRI - Anatomic Imaging of the Ankle 3  Open this link in a new window
    
SlidersSliders Overview

 
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• Related Searches:
    • Spectral Presaturation Inversion Recovery
    • Short T1 Inversion Recovery
    • Fat Saturation
    • Spectral Selection Attenuated Inversion Recovery
    • Shoulder MRI
 
Further Reading:
  Basics:
Techniques of Fat Suppression(.pdf)
   by cds.ismrm.org    
  News & More:
Enhanced Fast GRadient Echo 3-Dimensional (efgre3D) or THRIVE
   by www.mri.tju.edu    
Ultrashort echo time (UTE) MRI of the spine in thalassaemia
February 2004   by bjr.birjournals.org    
MRI Resources 
DICOM - Software - MRI Training Courses - Stimulator pool - Pediatric and Fetal MRI - Crystallography
 
FerumoxideInfoSheet: - Contrast Agents - 
Intro, Overview, 
Characteristics, 
Types of, 
etc.
 
Short name: AMI-25, generic name: Ferumoxide (SPIO)
Ferumoxides are superparamagnetic (T2*) MRI contrast agents, so the largest signal change is on T2 and T2* weighted images.
The agent distributes relatively rapidly to organs with reticuloendothelial cells primarily the liver, spleen and bone marrow. The liver shows decreased signal intensity, as does the spleen and marrow. The agent is taken up by the normal liver, resulting in increased CNR between tumor and normal liver. Hepatocellular lesions, such as adenoma or focal nodular hyperplasia, contain reticuloendothelial cells, so they will behave similar to the liver, with decreased signal on T2 weighted images. On T1 images, there is typically some circulating contrast agent, and blood vessels show increased signal intensity.
Current MRI protocols involve T1 weighted breath-hold gradient echo images of the liver, and fast spin echo T2 weighted pictures. This requires about 15 minutes. The patient is then removed from the scanner, and the contrast agent administered. After contrast administration, the same pulse sequences are again repeated.
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• View the DATABASE results for 'Ferumoxide' (5).Open this link in a new window

 
Further Reading:
  Basics:
Comparison of Two Superparamagnetic Viral-Sized Iron Oxide Particles Ferumoxides and Ferumoxtran-10 with a Gadolinium Chelate in Imaging Intracranial Tumors
2002   by www.ajnr.org    
Optimized Labelling of Human Monocytes with Iron Oxide MR Contrast Agents
Sunday, 30 November 2003   by rsna2003.rsna.org    
MRI Resources 
Open Directory Project - Universities - Shielding - Used and Refurbished MRI Equipment - Health - MRCP
 
Imaging of the ExtremitiesMRI Resource Directory:
 - Musculoskeletal and Joint MRI -
 
Knee and shoulder MRI exams are the most commonly requested musculoskeletal MRI scans. Other MR imaging of the extremities includes hips, ankles, elbows, and wrists. Orthopedic imaging requires very high spatial resolution for reliable small structure definition and therefore places extremely high demands on SNR.
Exact presentation of joint pathology expects robust and reliable fat suppression, often under difficult conditions like off-center FOV, imaging at the edge of the field homogeneity or in regions with complex magnetic susceptibility.
MR examinations can evaluate meniscal dislocations, muscle fiber tears, tendon disruptions, tendinitis, and diagnose bone tumors and soft tissue masses. MR can also demonstrate acute fractures that are radiographically impossible to see. Evaluation of articular cartilage for traumatic injury or assessment of degenerative disease represents an imaging challenge, which can be overcome by high field MRI applications. Currently, fat-suppressed 3D spoiled gradient echo sequences and density weighted fast spin echo sequences are the gold-standard techniques used to assess articular cartilage.
Open MRI procedures allow the kinematic imaging of joints, which provides added value to any musculoskeletal MRI practice. This technique demonstrates the actual functional impingements or positional subluxations of joints. In knee MRI examinations, the kinematical patellar study can show patellofemoral joint abnormalities.

See also Open MRI, Knee MRI, Low Field MRI.
 
Images, Movies, Sliders:
 MRI - Anatomic Imaging of the Foot  Open this link in a new window
    
SlidersSliders Overview

 Anatomic Imaging of the Shoulder  Open this link in a new window
      

Courtesy of  Robert R. Edelman

 MRI - Anatomic Imaging of the Ankle 2  Open this link in a new window
    
SlidersSliders Overview

 Anatomic MRI of the Knee 1  Open this link in a new window
    
SlidersSliders Overview

 
Radiology-tip.comradJoint Scintigraphy,  Arthrography
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Medical-Ultrasound-Imaging.comSonography,  Musculoskeletal and Joint Ultrasound
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• View the DATABASE results for 'Imaging of the Extremities' (5).Open this link in a new window

 
Further Reading:
  Basics:
Musculoskeletal MRI at 3.0 T: Relaxation Times and Image Contrast
Sunday, 1 August 2004   by www.ajronline.org    
Optimizing Musculoskeletal MR
   by rad.usuhs.mil    
VALUE OF 3D T1W & STIR MRI SEQUENCES IN DIAGNOSING EROSIONS IN RHEUMATOID ARTHRITIS
   by www.bocaradiology.com    
Comparison of New Methods for Magnetic Resonance Imaging of Articular Cartilage(.pdf)
2002
  News & More:
MRI of Hand, Foot May Predict RA in Undifferentiated Arthritis
Monday, 24 January 2022   by consumer.healthday.com    
MRI-Detected Erosions of the Small Joints Not Predictive of Later Rheumatoid Arthritis
Tuesday, 7 July 2020   by www.rheumatologyadvisor.com    
MRI Superior to Radiography in Capturing Joint Changes That Signal Future Bleeds, Study Says
Friday, 7 February 2020   by hemophilianewstoday.com    
3D 'bone maps' could spot early signs of osteoporosis
Monday, 27 February 2017   by www.gmanetwork.com    
Is magnetic resonance imaging necessary in isolated greater trochanter fracture? A systemic review and pooled analysis
Thursday, 24 December 2015   by www.ncbi.nlm.nih.gov    
Researcher uses MRI to measure joint's geometry and role in severe knee injury
Tuesday, 23 September 2014   by medicalxpress.com    
MRI technique allows study of wrist in motion
Monday, 6 January 2014   by www.healthimaging.com    
Searchterm 'Fast Spin Echo' was also found in the following service: 
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Forum  (3)  
 
Liver ImagingForum -
related threadsMRI Resource Directory:
 - Liver Imaging -
 
Liver imaging can be performed with sonography, computed tomography (CT) and magnetic resonance imaging (MRI). Ultrasound is, caused by the easy access, still the first-line imaging method of choice; CT and MRI are applied whenever ultrasound imaging yields vague results. Indications are the characterization of metastases and primary liver tumors e.g., benign lesions such as focal nodular hyperplasia (FNH), adenoma, hemangioma and malignant lesions (cancer) such as hepatocellular carcinomas (HCC). The decision, which medical imaging modality is more suitable, MRI or CT, is dependent on the different factors. CT is less costly and more widely available; modern multislice scanners provide high spatial resolution and short scan times but has the disadvantage of radiation exposure.
With the introduction of high performance MR systems and advanced sequences the image quality of MRI for the liver has gained substantially. Fast spin echo or single shot techniques, often combined with fat suppression, are the most common T2 weighted sequences used in liver MRI procedures. Spoiled gradient echo sequences are used as ideal T1 weighted sequences for evaluating of the liver. The repetition time (TR) can be sufficiently long to acquire enough sections covering the entire liver in one pass, and to provide good signal to noise. The TE should be the shortest in phase echo time (TE), which provides strong T1 weighting, minimizes magnetic susceptibility effects, and permits acquisition within one breath hold to cover the whole liver. A flip angle of 80° provides good T1 weighting and less of power deposition and tissue saturation than a larger flip angle that would provide comparable T1 weighting.
Liver MRI is very dependent on the administration of contrast agents, especially when detection and characterization of focal lesions are the issues. Liver MRI combined with MRCP is useful to evaluate patients with hepatic and biliary disease.
Gadolinium chelates are typical non-specific extracellular agents diffusing rapidly to the extravascular space of tissues being cleared by glomerular filtration at the kidney. These characteristics are somewhat problematic when a large organ with a huge interstitial space like the liver is imaged. These agents provide a small temporal imaging window (seconds), after which they begin to diffuse to the interstitial space not only of healthy liver cells but also of lesions, reducing the contrast gradient necessary for easy lesion detection. Dynamic MRI with multiple phases after i.v. contrast media (Gd chelates), with arterial, portal and late phase images (similar to CT) provides additional information.
An additional advantage of MRI is the availability of liver-specific contrast agents (see also Hepatobiliary Contrast Agents). Gd-EOB-DTPA (gadoxetate disodium, Gadolinium ethoxybenzyl dimeglumine, EOVIST Injection, brand name in other countries is Primovist) is a gadolinium-based MRI contrast agent approved by the FDA for the detection and characterization of known or suspected focal liver lesions.
Gd-EOB-DTPA provides dynamic phases after intravenous injection, similarly to non-specific gadolinium chelates, and distributes into the hepatocytes and bile ducts during the hepatobiliary phase. It has up to 50% hepatobiliary excretion in the normal liver.
Since ferumoxides are not eliminated by the kidney, they possess long plasmatic half-lives, allowing circulation for several minutes in the vascular space. The uptake process is dependent on the total size of the particle being quicker for larger particles with a size of the range of 150 nm (called superparamagnetic iron oxide). The smaller ones, possessing a total particle size in the order of 30 nm, are called ultrasmall superparamagnetic iron oxide particles and they suffer a slower uptake by RES cells. Intracellular contrast agents used in liver MRI are primarily targeted to the normal liver parenchyma and not to pathological cells. Currently, iron oxide based MRI contrast agents are not marketed.
Beyond contrast enhanced MRI, the detection of fatty liver disease and iron overload has clinical significance due to the potential for evolution into cirrhosis and hepatocellular carcinoma. Imaging-based liver fat quantification (see also Dixon) provides noninvasively information about fat metabolism; chemical shift imaging or T2*-weighted imaging allow the quantification of hepatic iron concentration.

See also Abdominal Imaging, Primovistâ„¢, Liver Acquisition with Volume Acquisition (LAVA), T1W High Resolution Isotropic Volume Examination (THRIVE) and Bolus Injection.

For Ultrasound Imaging (USI) see Liver Sonography at Medical-Ultrasound-Imaging.com.
 
Images, Movies, Sliders:
 Anatomic Imaging of the Liver  Open this link in a new window
      

 MRI Liver T2 TSE  Open this link in a new window
    
 
Radiology-tip.comradAbdomen CT,  Biliary Contrast Agents
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Medical-Ultrasound-Imaging.comLiver Sonography,  Vascular Ultrasound Contrast Agents
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• View the DATABASE results for 'Liver Imaging' (13).Open this link in a new window


• View the NEWS results for 'Liver Imaging' (10).Open this link in a new window.
 
Further Reading:
  Basics:
Comparison of liver scintigraphy and the liver-spleen contrast in Gd-EOB-DTPA-enhanced MRI on liver function tests
Thursday, 18 November 2021   by www.nature.com    
Liver Imaging Today
Friday, 1 February 2013   by www.healthcare.siemens.it    
Elastography: A Useful Method in Depicting Liver Hardness
Thursday, 15 April 2010   by www.sciencedaily.com    
Iron overload: accuracy of in-phase and out-of-phase MRI as a quick method to evaluate liver iron load in haematological malignancies and chronic liver disease
Friday, 1 June 2012   by www.ncbi.nlm.nih.gov    
  News & More:
Utility and impact of magnetic resonance elastography in the clinical course and management of chronic liver disease
Saturday, 20 January 2024   by www.nature.com    
Even early forms of liver disease affect heart health, Cedars-Sinai study finds
Thursday, 8 December 2022   by www.eurekalert.org    
For monitoring purposes, AI-aided MRI does what liver biopsy does with less risk, lower cost
Wednesday, 28 September 2022   by radiologybusiness.com    
Perspectum: High Liver Fat (Hepatic Steatosis) Linked to Increased Risk of Hospitalization in COVID-19 Patients With Obesity
Monday, 29 March 2021   by www.businesswire.com    
EMA's final opinion confirms restrictions on use of linear gadolinium agents in body scans
Friday, 21 July 2017   by www.ema.europa.eu    
T2-Weighted Liver MRI Using the MultiVane Technique at 3T: Comparison with Conventional T2-Weighted MRI
Friday, 16 October 2015   by www.ncbi.nlm.nih.gov    
EORTC study aims to qualify ADC as predictive imaging biomarker in preoperative regimens
Monday, 4 January 2016   by www.eurekalert.org    
MRI effectively measures hemochromatosis iron burden
Saturday, 3 October 2015   by medicalxpress.com    
Total body iron balance: Liver MRI better than biopsy
Sunday, 15 March 2015   by www.eurekalert.org    
MRI Resources 
Image Quality - Developers - Software - Coils - MRI Accidents - Most Wanted
 
Magnetic Resonance MyelographyMRI Resource Directory:
 - MR Myelography -
 
MR myelography is studying the spinal canal and subarachnoid space by high-resolution MRI with a technique in which a sequence with strong T2 weighting is used to provide high contrast between the "dark" spinal cord and its nerves and the surrounding "bright" cerebrospinal fluid. MR myelography as part of an entire MR examination has virtually replaced X-ray myelography. Used sequences are T2 weighted fast spin echo pulse sequences or a refocused gradient echo pulse sequence with strong T2 weighting.

See also the related poll result: 'MRI will have replaced 50% of x-ray exams by'
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• View the DATABASE results for 'Magnetic Resonance Myelography' (4).Open this link in a new window

MRI Resources 
Implant and Prosthesis - MRI Technician and Technologist Schools - Mass Spectrometry - MRCP - MR Guided Interventions - Bioinformatics
 
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