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 'Gradient Echo Sequence' 
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Result : Searchterm 'Gradient Echo Sequence' found in 5 terms [] and 80 definitions []
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Searchterm 'Gradient Echo Sequence' was also found in the following services: 
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Balanced Fast Field EchoInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.MRI Resource Directory:
 - Sequences -
 
(bFFE) A FFE sequence using a balanced gradient waveform. A balanced sequence starts out with a RF pulse of 90° or less and the spins in the steady state. Before the next TR in the slice phase and frequency encoding, gradients are balanced so their net value is zero. Now the spins are prepared to accept the next RF pulse, and their corresponding signal can become part of the new transverse magnetization. Since the balanced gradients maintain the transverse and longitudinal magnetization, the result is, that both T1 and T2 contrast are represented in the image. This pulse sequence produces images with increased signal from fluid, along with retaining T1 weighted tissue contrast. Because this form of sequence is extremely dependent on field homogeneity, it is essential to run a shimming prior the acquisition. A fully balanced (refocused) sequence would yield higher signal, especially for tissues with long T2 relaxation times.

See Steady State Free Precession and Gradient Echo Sequence.
 
Images, Movies, Sliders:
 Cardiac Infarct Short Axis Cine bFFE 1  Open this link in a new window
    
 
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Further Reading:
  News & More:
T1rho-prepared balanced gradient echo for rapid 3D T1rho MRI
Monday, 1 September 2008   by www.ncbi.nlm.nih.gov    
Utility of the FIESTA Pulse Sequence in Body Oncologic Imaging: Review
June 2009   by www.ajronline.org    
MRI Resources 
Blood Flow Imaging - Veterinary MRI - IR - Stent - Journals - Anatomy
 
Black Boundary ArtifactInfoSheet: - Artifacts - 
Case Studies, 
Reduction Index, 
etc.MRI Resource Directory:
 - Artifacts -
 
Quick Overview
Please note that there are different common names for this artifact.
Artifact Information
NAME
Black boundary, dark boundary, contour, chemical shift, relief
DESCRIPTION
Black contours at boundaries
Black boundary artifacts are black lines following voxels where both water and fat protons are present in the same voxel. This artifact arise along the boundary of organs or tissues perpendicular to the frequency encoding direction, and occurs preferentially in gradient echo sequences with out of phase echo times.
mri safety guidance
Image Guidance
Fat suppression techniques eliminate this artifact. For artifact reducing helps a smaller water fat shift (high bandwidth), a higher matrix or/and an in phase TE.

See also Chemical Shift Artifact.
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• View the DATABASE results for 'Black Boundary Artifact' (4).Open this link in a new window

 
Further Reading:
  Basics:
What is chemical shift artefact? Why does it occur? How many Hz at 1.5 T?
   by www.revisemri.com    
MRI Resources 
Hospitals - Intraoperative MRI - MRI Technician and Technologist Schools - NMR - Service and Support - IR
 
Breath Hold ImagingMRI Resource Directory:
 - Abdominal Imaging -
 
Breath hold imaging in MRI is a technique with one ore more stoppage of breathing during the sequence and require therefore a short scan time. Breath hold techniques are used with fast gradient echo sequences in thoracic or abdominal regions with much respiratory movement.
Breath hold cine MRI techniques are used in cardiovascular imaging and provide detailed views of the beating heart in different cardiac axes.
Breath hold imaging requires the full cooperation of the patient, caused by usual MRI scan times from 15 to 20 sec.. In some cases breath holding can be practiced outside the MRI scanner to improve patient cooperation with the examination. Shorter scan times e.g. by parallel imaging techniques, or the administration of oxygen can help the patient to hold the breath during the scan.
See also Abdominal Imaging.
 
Images, Movies, Sliders:
 MRI Upper Abdomen T1 with Contrast  Open this link in a new window
 Normal Dual Inversion Fast Spin-echo  Open this link in a new window
 Anatomic Imaging of the Lungs  Open this link in a new window
 
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• View the DATABASE results for 'Breath Hold Imaging' (7).Open this link in a new window

 
Further Reading:
  News & More:
The Effects of Breathing Motion on DCE-MRI Images: Phantom Studies Simulating Respiratory Motion to Compare CAIPIRINHA-VIBE, Radial-VIBE, and Conventional VIBE
Tuesday, 7 February 2017   by www.kjronline.org    
Controlling patient's breathing makes cardiac MRI more accurate
Friday, 13 May 2016   by www.upi.com    
Accurate T1 Quantification Using a Breath-hold Inversion Recovery TrueFISP Sequence
2003   by rsna2003.rsna.org    
Searchterm 'Gradient Echo Sequence' was also found in the following services: 
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Completely Balanced Steady StateInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.MRI Resource Directory:
 - Sequences -
 
(CBASS) A gradient echo sequence with balanced waveform.

See Steady State Free Precession and Balanced Sequence.
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• View the DATABASE results for 'Completely Balanced Steady State' (2).Open this link in a new window

MRI Resources 
Breast Implant - Online Books - Intraoperative MRI - Hospitals - Spectroscopy pool - Service and Support
 
Constructive Interference Steady StateInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
(CISS) This gradient echo sequence is a stimulated T2 echo. Two TrueFISP sequences are acquired with differing RF pulses and than combined for strong T2 Weighted high resolution 3D images.
These TrueFISP sequences are normally affected by dark phase dispersion bands, which are caused by patient induced local field inhomogeneities and made prominent by the relatively long TR used. The different excitation pulse regimes offset these bands in the 2 sequences. Combining the images results in a picture free of banding. The image combination is performed automatically after data collection, adding some time to the reconstruction process. The advantage of the 3D CISS sequence is its combination of high signal levels and extremely high spatial resolution.
Used for, e.g. inner ear, cranial nerves and cerebellum.

See also Steady State Free Precession.
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Further Reading:
  News & More:
Pediatric and Adult Cochlear Implantation1
2003   by radiographics.rsnajnls.org    
MRI Resources 
Spectroscopy pool - Open Directory Project - Examinations - Mobile MRI - Devices - MR Myelography
 
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