Magnetic Resonance - Technology Information Portal Welcome to MRI Technology
Info
  Sheets

Out-
      side
 



 
 MRI Database 
SEARCH FOR    
  2 3 5 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
previous     16 - 20 (of 98)     next 
Fa-Fa   Fa-Fa   Fa-Fa   Fa-Fa     Fa-Fe   Fe-Fe   Fe-Fe   Fe-Fe   Fe-Fi   Fi-Fi   Fi-Fi   Fi-Fl   FL-Fl   Fl-Fl   Fl-Fl   Fo-Fo   FO-Fr   Fr-Fr   Fr-Fu   Fu-Fu   
MRI Resources 
Process Analysis - MRI Centers - MRA - Lung Imaging - Devices - MRI Technician and Technologist Jobs
 
Fast Scanning
 
A specialized technique usually associated with short TR, reduced flip angle and repeated 180° rephasing pulses.
spacer

• View the DATABASE results for 'Fast Scanning' (3).Open this link in a new window

 
Further Reading:
  News & More:
Ultra-Fast MRI Is Effective in Acute Neurological Emergency Diagnoses
Wednesday, 15 January 2020   by www.diagnosticimaging.com    
MR Fingerprinting Could Lead to Much Faster MRI Scans and Simpler Recognition of Pathology
Friday, 22 March 2013   by www.medgadget.com    
New Imaging Method Makes Brain Scans 7 Times Faster
Sunday, 9 January 2011   by www.dailytech.com    
Faster MRI scans could boost psychiatric research
Monday, 10 January 2011   by www.theengineer.co.uk    
Fast Spin EchoForum -
there are 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
 
spacer

• 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    
MRI Resources 
Non-English - Diffusion Weighted Imaging - Contrast Enhanced MRI - Journals - Chemistry - Functional MRI
 
Fast Spin Echo Optimization
 
FSE optimization runs a preliminary TR period at the central slice and compares the phase of each echo in the echo train. If the phases do not compliment each other the RF is recalibrated and then the entire sequence is run. If there is an error in calibrating the phases of each of the echoes artifacts will appear.
spacer
 
Further Reading:
  Basics:
RARE
Monday, 3 December 2012   by www2.warwick.ac.uk    
  News & More:
MYELIN-SELECTIVE MRI: PULSE SEQUENCE DESIGN AND OPTIMIZATION
   by www.imaging.robarts.ca    
Fast Spoiled Gradient EchoInfoSheet: - Sequences -
Intro, Overview, 
Types of, 
etc.
 
spacer
 
Further Reading:
  News & More:
3-D VOLUMETRIC IMAGING FOR STEREOTACTIC LESIONAL AND DEEP BRAIN STIMULATION SURGERY
Fast Spoiled Grass Sequence with IR PreparationInfoSheet: - Sequences -
Intro, Overview, 
Types of, 
etc.
 
(IR-FSPGR) This sequence uses an inversion pulse followed by a spoiled low flip angle and short TR gradient echo train to collect all partition data. The 3D-IR-FSPGR uses centric ordering of Gz. The selected TI is also the effective TI. The centric reordering strategy can lead to image blurring if a steady state is not achieved quickly with low flip angles (less than 20°).
spacer
MRI Resources 
Journals - Mobile MRI - Calculation - Knee MRI - Portals - Safety Products
 
previous       16 - 20 (of 98)      next 
Fa-Fa   Fa-Fa   Fa-Fa    Fa-Fa    Fa-Fe   Fe-Fe   Fe-Fe   Fe-Fe   Fe-Fi   Fi-Fi   Fi-Fi   Fi-Fl   FL-Fl   Fl-Fl   Fl-Fl   Fo-Fo   FO-Fr   Fr-Fr   Fr-Fu   Fu-Fu   
 Random Page
 
Share This Page
FacebookTwitterLinkedIn

MR-TIP    
Community   
User
Pass
Forgot your UserID/Password ?    



Next big thing in MRI will be :
AI 
remote operator 
personalized protocols 
helium-free 
molecular MRI 
portable MRI 

Look
      Ups





MR-TIP.com uses cookies! By browsing MR-TIP.com, you agree to our use of cookies.

Magnetic Resonance - Technology Information Portal
Member of SoftWays' Medical Imaging Group - MR-TIP • Radiology-TIP • Medical-Ultrasound-Imaging • 
Copyright © 2003 - 2024 SoftWays. All rights reserved. [ 29 March 2024]
Terms of Use | Privacy Policy | Advertising
 [last update: 2024-02-26 03:41:00]