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Searchterm 'sequence' was also found in the following services: 
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SequencesForum -
related threadsInfoSheet: - Sequences - 
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Overview, 
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 - Sequences -
 
A preselected set of RF (and/or gradient) magnetic field pulses and time spacing between these pulses; used in conjunction with magnetic field gradients and MR signal reception to produce MR images.

See also Pulse Sequence , Interpulse Times and the info sheet.
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Further Reading:
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Single Sequence Magnetic Resonance Imaging in Serous Otitis Media
Friday, 28 April 2023   by www.cureus.com    
Multiacquisition with variable resonance image combination T2 (MAVRIC SL T2) for postoperative cervical spine with artificial disc replacement
Friday, 11 November 2022   by www.nature.com    
High-resolution MRI enables direct imaging of neuronal activity - DIANA – direct imaging of neuronal activity
Friday, 18 November 2022   by physicsworld.com    
What MRI Sequences Produce the Highest Specific Absorption Rate (SAR), and Is There Something We Should Be Doing to Reduce the SAR During Standard Examinations?
Thursday, 16 April 2015   by www.ajronline.org    
MRI techniques improve pulmonary embolism detection
Monday, 19 March 2012   by medicalxpress.com    
MRI Resources 
Intraoperative MRI - Most Wanted - Research Labs - Mobile MRI Rental - Devices - Calculation
 
Cine SequenceInfoSheet: - Sequences - 
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Overview, 
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Cine sequences used in cardiovascular MRI are collection of images (usually at the same spatial location) covering of one full period of cardiac cycle or over several periods in order to obtain complete coverage.
The pulse sequence used, is either a standard gradient echo pulse sequence, a segmented data acquisition, a gradient echo EPI sequence or a gradient echo with balanced gradient waveform. In cardiac gating studies it is possible to assign consecutive lines either to different images, yielding a multiphase sequence with as many images as lines, or the lines are grouped together into segments and assigned to the same image. The overall time to acquire such a segment has to be small compared to the RR-interval of the cardiac cycle, i. e. 50 ms, and hence contains typically 8 to 16 image lines.
This strategy is called segmented data acquisition, and has the advantage of reducing overall imaging time for cardiac images so that they can be acquired within a breath hold, but obviously decreasing the temporal resolution of each individual image. This method shows dynamic processes, such as the ejection of blood out of the heart into the aorta, by means of fast imaging and displaying the resulting images in a sequential-loop, the impression of a real-time movie is generated. Ejection fractions and stroke volumes calculated from these cine MRI images in different cardiac axes have been shown to be more accurate than any other imaging modality.

See also Cardiac Gating.
 
Images, Movies, Sliders:
 Angulation of Cardiac Planes Cine Images of Septal Infarct  Open this link in a new window
      

Courtesy of  Robert R. Edelman

 Cardiac Infarct Short Axis Cine Overview  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 Infarct 4 Chamber Cine  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 
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Further Reading:
  News & More:
Study Shows Cardiac MRI Use Reduces Adverse Events for Patients with Acute Chest Pain
Monday, 10 June 2013   by www.healthcanal.com    
Study identifies new way to predict prognosis for heart failure patients
Tuesday, 10 December 2013   by medicalxpress.com    
MRI Resources 
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Pulse SequenceForum -
related threadsMRI Resource Directory:
 - Sequences -
 
A pulse sequence is a preselected set of defined RF and gradient pulses, usually repeated many times during a scan, wherein the time interval between pulses and the amplitude and shape of the gradient waveforms will control NMR signal reception and affect the characteristics of the MR images. Pulse sequences are computer programs that control all hardware aspects of the MRI measurement process.
Usual to describe pulse sequences, is to list the repetition time (TR), the echo time (TE), if using inversion recovery, the inversion time (TI) with all times given in milliseconds, and in case of a gradient echo sequence, the flip angle. For example, 3000/30/1000 would indicate an inversion recovery pulse sequence with TR of 3000 msec., TE of 30 msec., and TI of 1000 msec.
Specific pulse sequence weightings are dependent on the field strength, the manufacturer and the pathology.

See also Interpulse Times.
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• View the DATABASE results for 'Pulse Sequence' (96).Open this link in a new window


• View the NEWS results for 'Pulse Sequence' (1).Open this link in a new window.
 
Further Reading:
  Basics:
MYELIN-SELECTIVE MRI: PULSE SEQUENCE DESIGN AND OPTIMIZATION
   by www.imaging.robarts.ca    
Faster speed, better spatial resolution lead 3T benefits
   by sipi.usc.edu    
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New MR sequence helps radiologists more accurately evaluate abnormalities of the uterus and ovaries
Thursday, 23 April 2009   by www.eurekalert.org    
Searchterm 'sequence' was also found in the following services: 
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Imaging Sequence
 
An imaging sequence is in magnetic resonance imaging a predefined set of radio frequency - and gradient pulses to excite the hydrogen nuclei of the object being imaged.
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• View the NEWS results for 'Imaging Sequence' (2).Open this link in a new window.
 
Further Reading:
  News & More:
New MR sequence helps radiologists more accurately evaluate abnormalities of the uterus and ovaries
Thursday, 23 April 2009   by www.eurekalert.org    
New MRI Technique Detects Genetic Condition That Attacks the Heart, Brain, Nerves
Wednesday, 2 October 2013   by www.sciencedaily.com    
MRI Resources 
Mobile MRI Rental - Software - Cardiovascular Imaging - Lung Imaging - Chemistry - Sequences
 
Balanced SequenceForum -
related threadsInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
This family of sequences uses a balanced gradient waveform. This waveform will act on any stationary spin on resonance between 2 consecutive RF pulses and return it to the same phase it had before the gradients were applied. A balanced sequence starts out with a RF pulse of 90° or less and the spins in the steady state. Prior to the next TR in the slice encoding, the phase encoding and the frequency encoding direction, 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. If the balanced gradients maintain the longitudinal and transverse 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 (like T2 weighted sequences), along with retaining T1 weighted tissue contrast. Balanced sequences are particularly useful in cardiac MRI. Because this form of sequence is extremely dependent on field homogeneity, it is essential to run a shimming prior the acquisition.
Usually the gray and white matter contrast is poor, making this type of sequence unsuited for brain MRI. Modifications like ramping up and down the flip angles can increase signal to noise ratio and contrast of brain tissues (suggested under the name COSMIC - Coherent Oscillatory State acquisition for the Manipulation of Image Contrast).
These sequences include e.g. Balanced Fast Field Echo (bFFE), Balanced Turbo Field Echo (bTFE), Fast Imaging with Steady Precession (TrueFISP, sometimes short TRUFI), Completely Balanced Steady State (CBASS) and Balanced SARGE (BASG).
 
Images, Movies, Sliders:
 Cardiac Infarct Short Axis Cine Overview  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 Infarct 4 Chamber Cine  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 
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• View the DATABASE results for 'Balanced Sequence' (5).Open this link in a new window

 
Further Reading:
  News & More:
Generic Eddy Current Compensation for Rapid Magnetic Resonance Imaging(.pdf)
   by www.switt.ch    
Magnetic resonance imaging guided musculoskeletal interventions at 0.23T: Chapter 4. Materials and methods
2002
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