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

Out-
      side
 



 
 'Fringe Field' 
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 'Fringe Field' found in 3 terms [] and 62 definitions []
previous     11 - 15 (of 65)     next
Result Pages : [1]  [2 3 4 5 6 7 8 9 10 11 12 13]
MRI Resources 
Movies - Libraries - Universities - Equipment - Pediatric and Fetal MRI - Sequences
 
Cardiac PacemakerMRI Resource Directory:
 - Safety -
 
A pacemaker is a device for internal or external battery-operated cardiac pacing to overcome cardiac arrhythmias or heart block. All implanted electronic devices are susceptible to the electromagnetic fields used in magnetic resonance imaging. Therefore, the main magnetic field, the gradient field, and the radio frequency (RF) field are potential hazards for cardiac pacemaker patients.
The pacemaker's susceptibility to static field and its critical role in life support have warranted special consideration. The static magnetic field applies force to magnetic materials. This force and torque effects rise linearly with the field strength of the MRI machines. Both, RF fields and pulsed gradients can induce voltages in circuits or on the pacing lead, which will heat up the tissue around e.g. the lead tip, with a potential risk of thermal injury.
Regulations for pacemakers provide that they have to switch to the magnet mode in static magnetic fields above 1.0 mT. In MR imaging, the gradient and RF fields may mimic signals from the heart with inhibition or fast pacing of the heart. In the magnet mode, most of the current pacemakers will pace with a fix pulse rate because they do not accept the heartsignals. However, the state of an implanted pacemaker will be unpredictable inside a strong magnetic field. Transcutaneous controller adjustment of pacing rate is a feature of many units. Some achieve this control using switches activated by the external application of a magnet to open/close the switch. Others use rotation of an external magnet to turn internal controls. The fringe field around the MRI magnet can activate such switches or controls. Such activations are a safety risk.
Areas with fields higher than 0.5 mT (5 Gauss Limit) commonly have restricted access and/or are posted as a safety risk to persons with pacemakers.
mri safety guidance
MRI Safety Guidance
A Cardiac pacemaker is because the risks, under normal circumstances an absolute contraindication for MRI procedures.
Nevertheless, with special precaution the risks can be lowered. Reprogramming the pacemaker to an asynchronous mode with fix pacing rate or turning off will reduce the risk of fast pacing or inhibition. Reducing the SAR value reduces the potential MRI risks of heating. For MRI scans of the head and the lower extremities, tissue heating also seems to be a smaller problem. If a transmit receive coil is used to scan the head or the feet, the cardiac pacemaker is outside the sending coil and possible heating is very limited.
spacer
• For this and other aspects of MRI safety see our InfoSheet about MRI Safety.
• Patient-related information is collected in our MRI Patient Information.

 
• Related Searches:
    • Magnetic Forces
    • Transmit Receive Coil
    • Cardiovascular Imaging
    • Brain MRI
    • MRI Procedure
 
Further Reading:
  Basics:
MRI in Patients with Implanted Devices: Current Controversies
Monday, 1 August 2016   by www.acc.org    
Magnetic resonance imaging in patients with cardiac pacemakers: era of MR Conditional designs
Thursday, 27 October 2011   by 7thspace.com    
  News & More:
Newer Heart Devices Safe During MRI
Monday, 23 August 2004   by www.hospimedica.com    
BIOTRONIK debuts pacemaker with continuous MRI sensor
Wednesday, 30 August 2023   by www.medicaldevice-network.com    
Patients with standard pacemakers, ICDs may safely undergo MRIs
Friday, 24 February 2017   by www.cardiovascularbusiness.com    
ITOCHU Named the Exclusive Distributor for ViewRay's MRI-Guided Radiation Therapy System in Japan
Thursday, 22 January 2015   by www.prnewswire.com    
Modern Implantable Heart Devices Safe For Use In MRI Scans
Wednesday, 16 March 2005   by www.sciencedaily.com    
MRI Safety Resources 
Stimulator pool - Implant and Prosthesis pool - Pregnancy - Safety Products - Stent
 
ENCORE 0.5T™InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.isoltech.co.kr/english/product/05t.htm 'MRI system is not an expensive equipment anymore. ENCORE developed by ISOL Technology is a low cost MRI system with the advantages like of the 1.0T MRI scanner. Developed specially for the overseas market, the ENCORE is gaining popularity in the domestic market by medium sized hospitals.
Due to the optimum RF and Gradient application technology. ENCORE enables to obtain high resolution imaging and 2D/3D Angio images which was only possible in high field MR systems.'
- Less consumption of the helium gas due to the ultra-lightweight magnet specially designed and manufactured for ISOL. - Cost efficiency MR system due to air cooling type (equivalent to permanent magnetic). - Patient processing speed of less than 20 minutes.'
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Short bore compact
Head, C-spine, L-spine, TMJ, Knee, Shoulder, General purpose, Phased Array System: 4 digital receiver channels (Up to 12 channels)
SYNCHRONIZATION
ECG/peripheral: Optional/yes, respiratory gating
SINGLE/MULTI SLICE
Image reconstruction time (2562 ) : 0.02 s
FOV
40 cm
BORE DIAMETER
or W x H
58 cm diameter
MAGNET WEIGHT
3200 kg
H*W*D
200 x 168 x 187 cm
COOLING SYSTEM TYPE
Air-cooled coil and amplifier
CRYOGEN USE
0.05 L/hr helium
STRENGTH
15 mT/m
5-GAUSS FRINGE FIELD
2.3 m / 3.1 m
Passive and active
spacer

• View the DATABASE results for 'ENCORE 0.5T™' (2).Open this link in a new window

MRI Resources 
Developers - Mass Spectrometry - Stimulator pool - Breast Implant - Safety Products - Health
 
Excelart AG™ with PianissimoInfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
http://www.medical.toshiba.com/clinical/radiology/15texcelart.htm From Toshiba America Medical Systems Inc.;
the EXCELART is a superconducting whole body MRI system with a short wide-bore magnet, operating at 1.5 T. It features powerful high-speed gradients with a revolutionary gradient acoustic noise reduction system: Pianissimo. The dramatic reduction of gradient acoustic noise by Pianissimo greatly enhances patient comfort during exams. The standard array platform and a wide range of array coils ensure excellent images. A powerful 64-bit RISC-based computer system and newly developed array processor realize high productivity.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Cylindrical Wide Short Bore
Opt. (WIP) Single and Multi Voxel
SYNCHRONIZATION
ECG: standard; peripheral: optional, respiratory gating
PULSE SEQUENCES
SE, FE, IR, FastSE, FastIR, FastFLAIR, Fast STIR, FastFE, FASE, Hybrid EPI, Multi Shot EPI; Angiography: 2D(gate/non-gate)/3D TOF, SORS-STC
IMAGING MODES
Single, multislice, volume study
TR
3.5-30000 msec
TE
8 msec min. SE; 1.2 msec min. FE
SINGLE/MULTI SLICE
less than 0.015 (256x256)
FOV
2 cm
1.0 min. 2-DFT: 0.2 min. 3-DFT
Up to 1024
MEASURING MATRIX
32-1024, phase;; 64-1024, freq.
PIXEL INTENSITY
256 gray levels
BORE DIAMETER
or W x H
65.5 cm, patient aperture
MAGNET WEIGHT
4050 kg (bare magnet incl. L-He)
H*W*D
235 x 219 x 199 cm
COOLING SYSTEM TYPE
Closed-loop water-cooled
CRYOGEN USE
Liquid helium: approx. less than 0.05 L/hr
STRENGTH
25 mT/m
5-GAUSS FRINGE FIELD
2.5 m / 4.0 m
Passive, active, auto-active
spacer

• View the DATABASE results for 'Excelart AG™ with Pianissimo' (2).Open this link in a new window

MRI Resources 
Developers - Education pool - RIS - Directories - Veterinary MRI - Raman Spectroscopy
 
Excelart XG™ with PianissimoInfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
http://www.medical.toshiba.com/clinical/radiology/15texcelart.htm From Toshiba America Medical Systems Inc.;
the EXCELART is a superconducting whole body MRI system with a short wide-bore magnet, operating at 1.5 T. It features powerful high-speed gradients with a revolutionary gradient acoustic noise reduction system: Pianissimo. The dramatic reduction of gradient acoustic noise by Pianissimo greatly enhances patient comfort during exams. The standard array platform and a wide range of array coils ensure excellent images. A powerful 64-bit RISC-based computer system and newly developed array processor realize high productivity.
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Cylindrical Wide Short Bore
Optional (WIP)
SYNCHRONIZATION
ECG/peripheral, respiratory gating
PULSE SEQUENCES
SE, FE, IR, FastSE, FastIR, FastFLAIR, Fast STIR, FastFE, FASE, Hybrid EPI, Multi Shot EPI; Angiography: 2D(gate/non-gate)/3D TOF, SORS-STC
IMAGING MODES
Single, multislice, volume study
TR
2.6-30000 msec
TE
8 msec min. SE; 0.9 msec min. FE
SINGLE/MULTI SLICE
less than 0.011 (256x256)
FOV
2 cm
1.0 min. 2-DFT: 0.2 min. 3-DFT
Up to 1024
MEASURING MATRIX
32-1024, phase;; 64-1024, freq.
PIXEL INTENSITY
256 gray levels
BORE DIAMETER
or W x H
65.5 cm, patient aperture
MAGNET WEIGHT
4050 kg (bare magnet incl. L-He)
H*W*D
235 x 219 x 199 cm
POWER REQUIREMENTS
380/400/415/440/480 V
COOLING SYSTEM TYPE
Closed-loop water-cooled
CRYOGEN USE
Liquid helium: approx. less than 0.05 L/hr
STRENGTH
25 mT/m
5-GAUSS FRINGE FIELD
2.5 m / 4.0 m
Passive, active, auto-active
spacer

• View the DATABASE results for 'Excelart XG™ with Pianissimo' (2).Open this link in a new window

 
Further Reading:
  News & More:
Angio, cardiac imaging top list for MR and CT
1999   by www.diagnosticimaging.com    
MRI Resources 
Bioinformatics - Portals - Mobile MRI Rental - NMR - Coils - Brain MRI
 
FORTE 3.0T™InfoSheet: - Devices -
Intro, 
Types of Magnets, 
Overview, 
etc.MRI Resource Directory:
 - Devices -
 
www.isoltech.co.kr/english/product/30t.htm From ISOL Technology
'Ultra high field MR system, it's right close to you. FORTE 3.0T is the new standard for the future ultra high field MR system. If you are pushing the limits of your existing clinical MR scanner, the FORTE will surely take you to the next level of diagnostic imaging. FORTE is the core leader of the medical technology in the 21st century. Proving effects of fMRI that cannot be measured with MRI less than 2.0T.'
Device Information and Specification
CLINICAL APPLICATION
Whole body
CONFIGURATION
Short bore compact
SYNCHRONIZATION
ECG/peripheral: Optional/yes, external trigger, respiratory gating
PULSE SEQUENCES
Spin echo, Gradient echo, Fast spin echo, Inversion recovery, 2D/3D Fast gradient echo sequences FLAIR/STIR, 2D/3D TOF
IMAGING MODES
2D/3D, T1, T2 and Diffusion//Perfusion imaging, MR Angiography package, Advanced EPI package, Multi-nuclei MR Spectroscopy package
FOV
40 cm
128 x 128, 256 x 256, 512 x 512, 1024 x 1024
BORE DIAMETER
or W x H
61 cm without body coil
MAGNET WEIGHT
12000 kg
H*W*D
260 x 220 x 235 cm
COOLING SYSTEM TYPE
Water-cooled coil and air-cooled amplifier
CRYOGEN USE
0.15 L/hr helium
STRENGTH
38 mT/m
5-GAUSS FRINGE FIELD
3.3 m / 5.2 m
Passive and active
spacer

• View the DATABASE results for 'FORTE 3.0T™' (2).Open this link in a new window

MRI Resources 
Contrast Enhanced MRI - Mass Spectrometry - Safety Products - General - Musculoskeletal and Joint MRI - Spectroscopy pool
 
previous      11 - 15 (of 65)     next
Result Pages : [1]  [2 3 4 5 6 7 8 9 10 11 12 13]
 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]