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

Out-
      side
 



 
 'Receiver' 
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
Result : Searchterm 'Receiver' found in 4 terms [] and 41 definitions []
previous     26 - 30 (of 45)     next
Result Pages : [1]  [2 3 4 5 6 7 8 9]
Searchterm 'Receiver' was also found in the following services: 
spacer
News  (2)  Resources  (1)  Forum  (5)  
 
Incoherent Gradient Echo (RF Spoiled)InfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
A gradient echo is generated by using a pair of bipolar gradient pulses. The gradient field is negatively pulsed, causing the spins of the xy-magnetization to dephase. A second gradient pulse is applied with the opposite polarity. During the pulsing, the spins that dephased begin to rephase and generate a gradient echo.
Spoiling can be accomplished by RF or a gradient. The incoherent RF spoiled type of a gradient echo sequence use a continuous shifting of the RF pulse to spoil the residual transverse magnetization. The phase of the RF excitation and receiver channel are varied pseudo randomly with each excitation cycle to prevent the xy magnetization from achieving steady state. T2* does not dominate image contrast, so T1 and PD weighting is practical. This method is effective and can be used to achieve a shorter TR, due to a lack of additional gradients. Spoiling eliminates the effect of the remaining xy-magnetization and leads to steady state longitudinal magnetization. These sequences can be used for breath hold, dynamic imaging and in cine and volume acquisitions.
spacer
 
• Related Searches:
    • Ernst Angle
    • Bipolar Gradient Pulse
    • Spoiled Gradient Echo Sequence
    • Coherent
    • Gradient Recalled Acquisition in Steady State
Searchterm 'Receiver' was also found in the following services: 
spacer
Radiology  (2) Open this link in a new windowUltrasound  (10) Open this link in a new window
MRI EquipmentInfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.
 
The MRI equipment consists of following components:
The magnet generates the magnetic field.
Shim coils make the magnetic field homogeneous.
Radio frequency coils transmit the radio signal into the body part being imaged.
Receiver coils detect the returning radio signals.
Gradient coils provide spatial localization of the signals.
Shielding coils produce a magnetic field that cancels the field from primary coils in regions where it is not desired.
The computer reconstructs the signals into the image.
The MRI scanner room is shielded by a faraday shield.
Different cooling systems cool the magnet, the scanner room and the technique room.

Better MRI equipment and software design along with the latest information technology improves system maintenance and overall communication. Software and digital imaging and communications in medicine (DICOM) compatibility allows to network into hospital databases, helps to modify pulse sequences, data post processing, and archiving via picture archiving and communication system (PACS).

See also the related poll result: 'Most outages of your scanning system are caused by failure of'
Radiology-tip.comradCT Scanner,  Radiography
spacer
Medical-Ultrasound-Imaging.comUltrasound Machine,  Ultrasound System Performance
spacer

• View the DATABASE results for 'MRI Equipment' (13).Open this link in a new window


• View the NEWS results for 'MRI Equipment' (4).Open this link in a new window.
 
Further Reading:
  News & More:
Low Power MRI Helps Image Lungs, Brings Costs Down
Thursday, 10 October 2019   by www.medgadget.com    
MRI safety targeted as new group offers credentialing test
Monday, 12 January 2015   by www.modernhealthcare.com    
Audio/Video System helps patients relax during MRI scans
Monday, 8 December 2014   by news.thomasnet.com    
Dräger introduces anaesthesia system for MRI environment
Wednesday, 12 December 2007   by www.mtbeurope.info    
MRI Resources 
Breast MRI - Image Quality - Most Wanted - MRI Reimbursement - Brain MRI - Online Books
 
Multi Echo Data Image CombinationInfoSheet: - Sequences - 
Intro, 
Overview, 
Types of, 
etc.
 
(MEDIC) MEDIC is a heavily T2* weighted spoiled gradient echo sequence with multiple echoes. MEDIC uses a series of identically phase encoded gradient echoes, sampled per line in k-space. Unipolar frequency encoding gradients are used to achieve flow compensation and to avoid off resonance effects. For each echo the magnitude images are reconstructed and postprocessed by using a sum of squares algorithm to improve the signal to noise ratio. The increased receiver bandwidth reduces the T2* effects and impairment of the spatial resolution.
The multi echo data image combination sequence is potentially useful in imaging of cartilage in joints.
spacer

• View the DATABASE results for 'Multi Echo Data Image Combination' (2).Open this link in a new window

Searchterm 'Receiver' was also found in the following services: 
spacer
News  (2)  Resources  (1)  Forum  (5)  
 
Multi Turn SolenoidInfoSheet: - Coils - 
Intro, 
Overview, 
etc.MRI Resource Directory:
 - Coils -
 
The multi turn solenoid is a volume coil that typically operates as the transmitter and receiver of RF energy. Multi turn solenoids can be wrapped, but the uniformity of the field suffers.
spacer

• View the DATABASE results for 'Multi Turn Solenoid' (2).Open this link in a new window

Searchterm 'Receiver' was also found in the following services: 
spacer
Radiology  (2) Open this link in a new windowUltrasound  (10) Open this link in a new window
NoiseForum -
related threadsInfoSheet: - Artifacts - 
Case Studies, 
Reduction Index, 
etc.
 
An undesirable background interference or disturbance that affects image quality.
The Noise is commonly characterized by the standard deviation of signal intensity in the image of a uniform object (phantom) in the absence of artifacts. The measured noise may depend on the particular phantom used due to variable effects on the Q of the receiver coil.
Noisy images appear when the SNR-Rate is too low - this is induced by the operator. Image artifacts and RF noise can often be caused by the presence and/or operation of a medical device in the MR environment. There are various noise sources in any electronic system, including Johnson noise, shot noise, thermal noise. Materials produce their own characteristic static magnetic field that can perturb the relationship between position and frequency essential to accurate image reconstruction.
RF noise, which often appears as static on the image, can be caused by a medical device located anywhere in the MR procedure room. RF noise is a result of excessive electromagnetic emissions from the medical device that interfere with the proper operation of the MR scanner. Since the MR procedure room is shielded from extraneous RF fields entering the room (Faraday cage), operation of electromagnetically noisy equipment outside the room does not typically affect the MR scanner.

See Signal to Noise Ratio and Radio Frequency Noise Artifact.
spacer

• View the DATABASE results for 'Noise' (86).Open this link in a new window


• View the NEWS results for 'Noise' (2).Open this link in a new window.
 
Further Reading:
  Basics:
Image Characteristics and Quality
   by www.sprawls.org    
  News & More:
Noise from Magnetic Resonance Imaging Can Have Short-Term Impact on Hearing
Thursday, 22 February 2018   by www.diagnosticimaging.com    
MRI Noise in Utero Not Harmful for Baby's Ears
Tuesday, 28 September 2010   by www.medgadget.com    
A Neural Mosaic Of Tones
Tuesday, 20 June 2006   by www.sciencedaily.com    
MRI Resources 
Portals - Abdominal Imaging - Bioinformatics - Equipment - Functional MRI - Manufacturers
 
previous      26 - 30 (of 45)     next
Result Pages : [1]  [2 3 4 5 6 7 8 9]
 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. [ 25 April 2024]
Terms of Use | Privacy Policy | Advertising
 [last update: 2024-02-26 03:41:00]