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Result : Searchterm 'Image Quality' found in 1 term [] and 44 definitions []
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Searchterm 'Image Quality' was also found in the following services: 
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News  (17)  Resources  (5)  Forum  (10)  
 
Amersham plcMRI Resource Directory:
 - Manufacturers -
 
www.amersham.com [This entry is marked for removal.]

GE Medical Systems and Amersham announced in April 2004 the completion of a share exchange acquisition of Amersham Health by GE. The result of this acquisition is the new GE Healthcare, based in the UK, totally owned by General Electric (GE).

Amersham plc, was a producer of contrast imaging agents used to enhance image quality in X-ray, magnetic resonance imaging, and ultrasound procedures. It was also a leading producer of radiopharmaceuticals used in nuclear medicine imaging. Amersham Health was the firm's imaging, diagnostics, and therapeutics segment. Amersham plc was involved in biotechnology research through its Amersham Biosciences unit, which made scanners, sequencers, microarrays, industrial separations, and other research supplies.
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Further Reading:
  News & More:
Recommended Share Exchange Acquisition by General Electric Company and GE Investments, Inc. of Amersham plc
Friday, 10 October 2003   by www.evaluatepharma.com    
Searchterm 'Image Quality' was also found in the following services: 
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Radiology  (13) Open this link in a new windowUltrasound  (35) Open this link in a new window
Arrhythmia Rejection
 
With this method irregular RR intervals in cardiac gating during cardiovascular imaging are rejected and then repeated to improve the image quality, whereby the cardiac frequency is used as a basis of the normal heart rate.
The RR interval window determines the percentage variation of the heart rate. Variations of the acquired data outside the window are rejected and not used in the image reconstruction. Also one interval after the arrhytmic beat will be rejected.
Arrhythmia rejection may be inappropriate for patients with certain pathologies, because if the RR interval is constant long, short, long, - all intervals would be rejected. Also a disadvantage is the time consume, but in some cases this function is mandatory, e.g. for diverse retrospective triggered sequences.
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Further Reading:
  Basics:
A Guide To Cardiac Imaging
   by www.simplyphysics.com    
  News & More:
Irregular heartbeat may lead to silent strokes
Wednesday, 5 November 2014   by www.techtimes.com    
MRI Resources 
Breast Implant - Artifacts - Lung Imaging - MRI Reimbursement - Breast MRI - Movies
 
ArtifactForum -
related threadsInfoSheet: - Artifacts - 
Case Studies, 
Reduction Index, 
etc.MRI Resource Directory:
 - Artifacts -
 
An image artifact is a structure not normally present but visible as a result of a limitation or malfunction in the hardware or software of the MRI device, or in other cases a consequence of environmental influences as heat or humidity or it can be caused by the human body (blood flow, implants etc.). The knowledge of MRI artifacts (brit. artefacts) and noise producing factors is important for continuing maintenance of high image quality. Artifacts may be very noticeable or just a few pixels out of balance but can give confusing artifactual appearances with pathology that may be misdiagnosed.
Changes in patient position, different pulse sequences, metallic artifacts, or other imaging variables can cause image distortions, which can be reduced by the operator; artifacts due to the MR system may require a service engineer.
Many types of artifacts may occur in magnetic resonance imaging. Artifacts in magnetic resonance imaging are typically classified as to their basic principles, e.g.:
•
Physiologic (motion, flow)
•
Hardware (electromagnetic spikes, ringing)
•
Inherent physics (chemical shift, susceptibility, metal)

Several techniques are developed to reduce these artifacts (e.g. respiratory compensation, cardiac gating, eddy current compensation) but sometimes these effects can also be exploited, e.g. for flow measurements.

See also the related poll result: 'Most outages of your scanning system are caused by failure of'
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Further Reading:
  Basics:
ARTEFACT VERSUS ARTIFACT
Saturday, 26 January 2002   by www.worldwidewords.org    
  News & More:
MRI results affected by movement? MIT researchers have an AI-powered solution
Friday, 25 August 2023   by healthimaging.com    
Magnetic eyelashes: A new source of MRI artifacts
Wednesday, 24 July 2019   by medicalxpress.com    
On the Horizon - Next Generation MRI
Wednesday, 23 October 2013   by thefutureofthings.com    
Searchterm 'Image Quality' was also found in the following services: 
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News  (17)  Resources  (5)  Forum  (10)  
 
Cervical Spine MRI
 
Cervical spine MRI is a suitable tool in the assessment of all cervical spine (vertebrae C1 - C7) segments (computed tomography (CT) images may be unsatisfactory close to the thoracic spine due to shoulder artifacts). The cervical spine is particularly susceptible to degenerative problems caused by the complex anatomy and its large range of motion.
Advantages of magnetic resonance imaging MRI are the high soft tissue contrast (particularly important in diagnostics of the spinal cord), the ability to display the entire spine in sagittal views and the capacity of 3D visualization. Magnetic resonance myelography is a useful supplement to conventional MRI examinations in the investigation of cervical stenosis. Myelographic sequences result in MR images with high contrast that are similar in appearance to conventional myelograms. Additionally, open MRI studies provide the possibility of weight-bearing MRI scan to evaluate structural positional and kinetic changes of the cervical spine.
Indications of cervical spine MRI scans include the assessment of soft disc herniations, suspicion of disc hernia recurrence after operation, cervical spondylosis, osteophytes, joint arthrosis, spinal canal lesions (tumors, multiple sclerosis, etc.), bone diseases (infection, inflammation, tumoral infiltration) and paravertebral spaces.
State-of-the-art phased array spine coils and high performance MRI machines provide high image quality and short scan time. Imaging protocols for the cervical spine includes sagittal T1 weighted and T2 weighted sequences with 3-4 mm slice thickness and axial slices; usually contiguous from C2 through T1. Additionally, T2 fat suppressed and T1 post contrast images are often useful in spine imaging.

See also Lumbar Spine MRI.
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• View the NEWS results for 'Cervical Spine MRI' (1).Open this link in a new window.
 
Further Reading:
  News & More:
Ultrafast MRI protocol reduces scan time by 10 minutes for cervical imaging
Monday, 26 September 2022   by healthimaging.com    
In Vivo 3-D Cervical Spine Kinematics Demonstrated
Thursday, 19 May 2011   by www.doctorslounge.com    
MRI Images at a 45-Degree Angle Through The Cervic al Neural Forami na:A Technique For Improved Visualization(.pdf)
2006   by www.painphysicianjournal.com    
Searchterm 'Image Quality' was also found in the following services: 
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Radiology  (13) Open this link in a new windowUltrasound  (35) Open this link in a new window
ContraindicationsForum -
related threadsMRI Resource Directory:
 - Safety -
 
The principal contraindications of the MRI procedure are mostly related to the presence of metallic implants in a patient. The risks of MRI scans increase with the used field strength. In general, implants are becoming increasingly MR safe and an individual evaluation is carried out for each case.
mri safety guidance
MRI Safety Guidance
Some patients should not be examined in MRI machines, or come closer than the 5 Gauss line to the system.

Absolute Contraindications for the MRI scan:
•
electronically, magnetically, and mechanically activated implants
•
ferromagnetic or electronically operated active devices like automatic cardioverter defibrillators
•
metallic splinters in the eye
•
ferromagnetic haemostatic clips in the central nervous system (CNS)

Patients with absolute contraindications should not be examined or only with special MRI safety precautions. Patients with an implanted cardiac pacemaker have been scanned on rare occasions, but pacemakers are generally considered an absolute contraindication. Relative contraindications may pose a relative hazard, and the type and location of an implant should be assessed prior to the MRI examination.

Relative Contraindications for the MRI scan:
•
other pacemakers, e.g. for the carotid sinus
•
lead wires or similar wires (MRI Safety risk)
•
prosthetic heart valves (in high fields, if dehiscence is suspected)
•
haemostatic clips (body)
•

Osteosynthesis material is usually anchored so well in the patients that no untoward effect will result. Another effect on metal parts in the patient's body is the heating of these parts through induction. In addition, image quality may be severely degraded. The presence of other metallic implants such as surgical clips etc. should be made known to the MRI operators. Most of these materials are non-magnetic, but if magnetic, they can pose a hazard.

See also MRI safety, Pregnancy, Claustrophobia and Tattoos.
Radiology-tip.comradRadiation Safety,  As Low As Reasonably Achievable
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Medical-Ultrasound-Imaging.comUltrasound Safety
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Further Reading:
  Basics:
MRI in Patients with Implanted Devices: Current Controversies
Monday, 1 August 2016   by www.acc.org    
Newer Heart Devices Safe During MRI
Monday, 23 August 2004   by www.hospimedica.com    
Physics of MRI Safety
   by www.aapm.org    
FDA Releases New Guidance On Establishing Safety, Compatibility Of Passive Implants In MR Environments
Tuesday, 16 December 2014   by www.meddeviceonline.com    
  News & More:
Women with permanent make-up tattoos suffer horrific facial burns after going in for MRI scans - which create an electric current in the ink
Monday, 4 July 2016   by www.dailymail.co.uk    
Positive diagnosis for neural therapeutic implants
Tuesday, 19 April 2016   by medicalxpress.com    
Codman Neuro develops new MRI-resistant programmable valve for treatment of hydrocephalus
Tuesday, 22 September 2015   by www.news-medical.net    
MRI Resources 
Mobile MRI - Developers - Liver Imaging - Quality Advice - Spine MRI - Services and Supplies
 
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