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 'T2 Weighted' 
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Result : Searchterm 'T2 Weighted' found in 2 terms [] and 44 definitions []
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Searchterm 'T2 Weighted' was also found in the following services: 
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Contrast Enhanced FLASHInfoSheet: - Sequences - 
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(CE FLASH) A fast T2 weighted imaging sequence utilizing refocused transverse coherence.
See Contrast Enhanced Echo Sequence.
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MRI Resources 
Mass Spectrometry - Nerve Stimulator - Diffusion Weighted Imaging - Services and Supplies - Developers - Liver Imaging
 
Contrast Enhanced Gradient Echo SequenceInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
Contrast enhanced GRE sequences provide T2 contrast but have a relatively poor SNR. Repetitive RF pulses with small flip angles together with appropriate gradient profiles lead to the superposition of two resonance signals.
The first signal is due to the free induction decay FID observed after the first and all ensuing RF excitations.
The second is a resonance signal obtained as a result of a spin echo generated by the second and all addicted RF-pulses.
Hence it is absent after the first excitation, it is a result of the free induction decay of the second to last RF-excitation and has a TE, which is almost 2TR. For this echo to occur the gradients have to be completely symmetrical relative to the half time between two RF-pulses, a condition that makes it difficult to integrate this pulse sequence into a multiple slice imaging technique. The second signal not only contains echo contributions from free induction decay, but obviously weakened by T2-decay. Since the echo is generated by a RF-pulse, it is truly T2 rather than T2* weighted. Correspondingly it is also less sensitive to susceptibility changes and field inhomogeneities.
Companies use different acronyms to describe certain techniques.
Different terms (see also acronyms) for these gradient echo pulse sequences:
CE-FAST Contrast Enhanced Fourier Acquired Steady State,
CE-FFE Contrast Enhanced Fast Field Echo,
CE-GRE Contrast Enhanced Gradient-Echo,
DE-FGR Driven Equilibrium FGR,
FADE FASE Acquisition Double Echo,
PSIF Reverse Fast Imaging with Steady State Precession,
SSFP Steady State Free Precession,
T2 FFE Contrast Enhanced Fast Field Echo (T2 weighted).

In this context, ‘contrast enhanced’ refers to the pulse sequence, it does not mean enhancement with a contrast agent.

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Manufacturers - Quality Advice - Education - Sequences - Cardiovascular Imaging - Mobile MRI Rental
 
Double Contrast SequenceInfoSheet: - Sequences - 
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Overview, 
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etc.
 
This sequence type is a TSE counterpart to double echo sequences. To keep the echo train as short as possible, only echoes for PD and T2 weighted images, where the phase encoding gradient has a small amplitude, are measured separately. The echoes that determine resolution are used in both raw data matrices. This reduces the number of echoes required. Also the SAR drops and more slices can be acquired in the same repetition time.

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Further Reading:
  Basics:
BASIC PRINCIPLES OF MR IMAGING
   by spinwarp.ucsd.edu    
Searchterm 'T2 Weighted' was also found in the following services: 
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News  (7)  Resources  (1)  Forum  (6)  
 
Dual Echo SequenceInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
(DE - dual / double echo) Dual echo sequences include images with different weightings and / or echo times and are used to obtain both, proton density and T2 weighted images or in phase and out of phase gradient echo images, simultaneously without increasing the measurement time.

 
Images, Movies, Sliders:
 MRI Liver In Phase  Open this link in a new window
 MRI Liver Out Of Phase  Open this link in a new window
 
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• View the DATABASE results for 'Dual Echo Sequence' (3).Open this link in a new window

 
Further Reading:
  Basics:
BASIC PRINCIPLES OF MR IMAGING
   by spinwarp.ucsd.edu    
  News & More:
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    
MRI Resources 
Pediatric and Fetal MRI - Hospitals - MR Myelography - Databases - General - Calculation
 
Gastrointestinal ImagingMRI Resource Directory:
 - Abdominal Imaging -
 
Rectal staging is necessary for the preoperative assessment of intra- and extramural tumor infiltration or the decision for adjuvant radio-chemotherapy. One indication of MRI with luminal contrast enhancement is small bowel enteroclysis after duodenal intubation for visualization of inflammatory bowel wall thickening and other complications.
"Double contrast" enhancement of the bowel lumen is the administration of plain water or water with methylcellulose along with heavily T2 weighted sequences or contrast enhanced T1 weighted sequences.
Several oral contrast agents have been used for small bowel MRI: Mannitol, metamucil, locust bean gum, and PEG. All provide sufficient bowel distension and homogeneity, but suffer from side effects such as diarrhea. The volume of PEG or mannitol administered must be not too large in order to achieve the best compromise between distension and acceptance by the patient.
MR colonography with positive bowel lumen enhancement requires higher concentrations of paramagnetic agents compared to the available dedicated enteral contrast agents, IV compounds are used to dope water enemas for this purpose.
Some investigators advocate negative bowel enhancement with Contrast Agents to suppress high signal bowel content in MRCP ( Magnetic resonance cholangiopancreaticography ). The use of a mixture of metamucil and 20 ml of gadolinium chelate provides good homogeneity and good tolerance without diarrhea.
 
Images, Movies, Sliders:
 MR Colonography Gadolinium per Rectum  Open this link in a new window
      

Courtesy of  Robert R. Edelman
 Pregnancy and Small Bowel Obstruction  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 
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• View the NEWS results for 'Gastrointestinal Imaging' (1).Open this link in a new window.
 
Further Reading:
  Basics:
Nottingham scientists exploit MRI technology to assist in the treatment of IBS
Thursday, 9 January 2014   by www.news-medical.net    
Hydro-MRI of the Small Bowel: Effect of Contrast Volume, Timing of Contrast Administration, and Data Acquisition on Bowel Distention
Sunday, 1 October 2006   by www.ajronline.org    
Usefulness of MR Imaging for Diseases of the Small Intestine: Comparison with CT
2000   by www.ncbi.nlm.nih.gov    
  News & More:
Advancing Clinical Trials with Medical Imaging: Spotlight on Immunologic Diseases
Tuesday, 28 April 2015   by www.clinicalleader.com    
MRI Resources 
MRI Centers - Blood Flow Imaging - Developers - Safety pool - IR - Services and Supplies
 
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