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

Out-
      side
 



 
 'Cardiac MRI' 
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 'Cardiac MRI' found in 1 term [] and 15 definitions [], (+ 19 Boolean[] results
1 - 5 (of 35)     next
Result Pages : [1]  [2 3 4]  [5 6 7]
Searchterm 'Cardiac MRI' was also found in the following services: 
spacer
News  (45)  Resources  (14)  Forum  (1)  
 
Cardiac MRIForum -
related threads
 
In the last years, cardiac MRI techniques have progressively improved. No other noninvasive imaging modality provides the same degree of contrast and temporal resolution for the assessment of cardiovascular anatomy and pathology. Contraindications MRI are the same as for other magnetic resonance techniques.
The primary advantage of MRI is extremely high contrast resolution between different tissue types, including blood. Moreover, MRI is a true 3 dimensional imaging modality and images can be obtained in any oblique plane along the true cardiac axes while preserving high temporal and spatial resolution with precise demonstration of cardiac anatomy without the administration of contrast media.
Due to these properties, MRI can precisely characterize cardiac function and quantify cavity volumes, ejection fraction, and left ventricular mass. In addition, cardiac MRI has the ability to quantify flow (see flow quantification), including bulk flow in vessels, pressure gradients across stenosis, regurgitant fractions and shunt fractions. Valve morphology and area can be determined and the severity of stenosis quantified. In certain disease states, such as myocardial infarction, the contrast resolution of MRI is further improved by the addition of extrinsic contrast agents (see myocardial late enhancement).
A dedicated cardiac coil, and a field strength higher than 1 Tesla is recommended to have sufficient signal. Cardiac MRI acquires ECG gating. Cardiac gating (ECGs) obtained within the MRI scanner, can be degraded by the superimposed electrical potential of flowing blood in the magnetic field. Therefore, excellent contact between the skin and ECG leads is necessary. For male patients, the skin at the lead sites can be shaved. A good cooperation of the patient is necessary because breath holding at the end of expiration is practiced during the most sequences.

See also Displacement Encoding with Stimulated Echoes.
For Ultrasound Imaging (USI) see Cardiac Ultrasound at Medical-Ultrasound-Imaging.com.

See also the related poll results: 'In 2010 your scanner will probably work with a field strength of' and 'MRI will have replaced 50% of x-ray exams by'
 
Images, Movies, Sliders:
 Infarct 4 Chamber Cine  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 MVP Parasternal  Open this link in a new window
    

Courtesy of  Robert R. Edelman
 Delayed Myocardial Contrast Enhancement from Infarct  Open this link in a new window
      

Courtesy of  Robert R. Edelman
 
spacer
 
• Share the entry 'Cardiac MRI':  Facebook  Twitter  LinkedIn  
 
• Related Searches:
    • Cardiac Axes
    • Heart MRI
    • Cardiac Risks
    • Cardiac Gating
    • Cardiovascular Imaging
 
Further Reading:
  Basics:
Cardiac MRI - Technical Aspects Primer
Wednesday, 7 August 2002
Prediction of Myocardial Viability by MRI
1999   by circ.ahajournals.org    
  News & More:
MRI technology visualizes heart metabolism in real time
Friday, 18 November 2022   by medicalxpress.com    
Even early forms of liver disease affect heart health, Cedars-Sinai study finds
Thursday, 8 December 2022   by www.eurekalert.org    
MRI sheds light on COVID vaccine-associated heart muscle injury
Tuesday, 15 February 2022   by www.sciencedaily.com    
Radiologists must master cardiac CT, MRI to keep pace with demand: The heart is not a magical organ
Monday, 1 March 2021   by www.radiologybusiness.com    
Diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) in the heart (myocardium)
Sunday, 30 August 2020   by github.com    
Non-invasive diagnostic procedures for suspected CHD: Search reveals informative evidence
Wednesday, 8 July 2020   by medicalxpress.co    
Cardiac MRI Becoming More Widely Available Thanks to AI and Reduced Exam Times
Wednesday, 19 February 2020   by www.dicardiology.com    
Controlling patient's breathing makes cardiac MRI more accurate
Friday, 13 May 2016   by www.upi.com    
Precise visualization of myocardial injury: World's first patient-based cardiac MRI study using 7T MRI
Wednesday, 10 February 2016   by medicalxpress.com    
New technique could allow for safer, more accurate heart scans
Thursday, 10 December 2015   by www.gizmag.com    
Searchterm 'Cardiac MRI' was also found in the following service: 
spacer
Radiology  (2) Open this link in a new window
Cardiovascular ImagingMRI Resource Directory:
 - Cardiovascular Imaging -
 
Cardiovascular MR imaging includes the complete anatomical display of the heart with CINE imaging of all phases of the heartbeat. Ultrafast techniques make breath hold three-dimensional coverage of the heart in different cardiac axes feasible. Cardiac MRI provides reliable anatomical and functional assessment of the heart and evaluation of myocardial viability and coronary artery disease by a noninvasive diagnostic imaging technique.
Cardiovascular MRI offers potential advantages over radioisotopic techniques because it provides superior spatial resolution, does not use ionizing radiation, has no imaging orientations constraints and contrast resolution better than echocardiography. It also offers direct visualization and characterization of atherosclerotic plaques and diseased vessel walls and surrounding tissues in cardiovascular research.
MRI perfusion approaches measure the alteration of regional myocardial magnetic properties after the intravenous injection of contrast agents and assess the extent of injury after a myocardial infarction and the presence of myocardial viability with a technique based on late enhancement. Extracellular MRI contrast agents, like Gd-DTPA, accumulate only in irreversibly damaged myocardium after a time period of at least 10 minutes.
This type of patients may also have an implanted cardiac stent, bypass or a cardiac pacemaker and special caution should be observed on the MRI safety and the contraindications. While a number of coronary stents have been tested and reported to be MRI compatible, coronary stents must be assessed on an individual basis, with the medical team weighing the risks and benefits of the MRI procedure.

Cardiac MRI overview:
Myocardial perfusion imaging and viability
Calculation of ventricular volume, myocardial mass and wall thickness
Functional parameters
Description of a stenosis or aneurysma
Anatomical display of the heart, vessels and the surrounding tissue

Cardiovascular MRI has become one of the most effective noninvasive imaging techniques for almost all groups of heart and vascular disease.
 
Images, Movies, Sliders:
 Angulation of Cardiac Planes Cine Images of Septal Infarct  Open this link in a new window
      

Courtesy of  Robert R. Edelman

 Left Circumflex Ischemia First-pass Contrast Enhancement  Open this link in a new window
      

Courtesy of  Robert R. Edelman

 Delayed Myocardial Contrast Enhancement from Infarct  Open this link in a new window
 
spacer

• View the DATABASE results for 'Cardiovascular Imaging' (18).Open this link in a new window


• View the NEWS results for 'Cardiovascular Imaging' (6).Open this link in a new window.
 
Further Reading:
  Basics:
Cardiac MRI - Technical Aspects Primer
Wednesday, 7 August 2002
Coronary Artery Disease: Combined Stress MR Imaging Protocol-One-Stop Evaluation of Myocardial Perfusion and Function1
   by radiology.rsnajnls.org    
A Guide To Cardiac Imaging
   by www.simplyphysics.com    
  News & More:
New Imaging Technique Reveals Different Heart Motions by Age, Gender
Thursday, 10 December 2009   by www.sciencedaily.com    
MRI Resources 
Universities - Jobs - IR - Anatomy - Calculation - Mass Spectrometry
 
Coronary AngiographyMRI Resource Directory:
 - Cardiovascular Imaging -
 
(MRI-CA, MRCA) The noninvasive imaging of the coronary arteries using magnetic resonance imaging of the heart.
For cardiac MRI-CA, high performance machines are necessary with minimum 40mT/m and 300μsec slew rate.
2D and 3D acquisition are used for fast gradient echo sequences with techniques for minimizing cardiac and respiratory motion and suppressing the high signal of pericardial fat. The optimal sequences seem to be trueFISP, Balanced FFE or FIESTA with SMASH and SENSE techniques. Respiratory motion is minimized for 3D acquisitions by using respiratory gating, especially using navigator echoes (Navigator Technique) to track diaphragmatic and cardiac movement. Optimization of MR technique can provide mapping of long segments of the coronary arteries.
Blood pool agents are being applied to improve the reliability of coronary MR angiography. The major current clinical indication is the identification of coronary artery anomalies because the diagnostic accuracy's for identifying haemodynamically significant stenoses are variable depending of the image quality.

See also Magnetic Resonance Angiography, and Cardiac MRI.
spacer

• View the DATABASE results for 'Coronary Angiography' (7).Open this link in a new window

 
Further Reading:
  Basics:
Role of Magnetic Resonance Imaging in Visualizing Coronary Arteries
Monday, 2 August 2004   by www.clinmedres.org    
  News & More:
Graphic illustration
Tuesday, 12 February 2008   by www.theengineer.co.uk    
Searchterm 'Cardiac MRI' was also found in the following services: 
spacer
News  (45)  Resources  (14)  Forum  (1)  
 
Myocardial Late Enhancement
 
(LE) Myocardial late enhancement in contrast enhanced cardiac MRI has the ability to precisely delineate myocardial scar associated with coronary artery disease. Viability imaging implies evaluating infarcted myocardium to see whether there is enough viable tissue available for revascularization. The reversal of myocardial dysfunction is particularly relevant in patients with depressed ventricular function because revascularization improves long-term survival. In comparison to SPECT and PET imaging, myocardial late enhancement MRI demonstrates areas of delayed enhancement exactly in correlation with the infarcted region.
Viability on cardiac MRI (CMR) is based on the fact that all infarcts enhance vividly 10-15 minutes after the administration of intravenous paramagnetic contrast agents. This enhancement represents the accumulation of gadolinium in the extracellular space, due to the loss of membrane integrity in the infarcted tissue. This phenomenon of delayed hyperenhancement has been proven to correlate with the actual extent of the infarct.
MRI myocardial late enhancement can quantify the size, location and transmural extent of the infarct. If the transmural extent of the infarct (region of enhancement on MRI) is less than 50% of the wall thickness, there will be improved contractility in that segment following revascularization. In areas of hypokinesia, if there is a rim of "black" or non-infarcted myocardium that is not contracting well, it indicates the presence of hibernating myocardium, which is likely to improve after revascularization of the artery supplying that particular territory.
The total duration of a myocardial late enhancement MR imaging protocol for viability is approximately 30 minutes, including scout images, first-pass images, cine images in two planes, and delayed myocardial enhancement images. In order to assess viable myocardium, the gadolinium contrast agent is injected at a dose of 0.15 to 0.2 mmol/kg. After about 10 minutes, short axis and long axis views (see cardiac axes) of the heart are obtained using an inversion prepared ECG gated gradient echo sequence. The inversion pulse is adjusted to suppress normal myocardium. Areas of nonviable myocardium retain extremely high signal intensity, black areas show normal tissue.

For Ultrasound Imaging (USI) see Myocardial Contrast Echocardiography at Medical-Ultrasound-Imaging.com.
spacer

• View the DATABASE results for 'Myocardial Late Enhancement' (6).Open this link in a new window

 
Further Reading:
  Basics:
A Guide To Cardiac Imaging
   by www.simplyphysics.com    
  News & More:
Prediction of Myocardial Viability by MRI
1999   by circ.ahajournals.org    
Geron Demonstrates hESC-derived cardiomyocytes improve heart function after myocardial infarction
Monday, 27 August 2007   by www.brightsurf.com    
Searchterm 'Cardiac MRI' was also found in the following service: 
spacer
Radiology  (2) Open this link in a new window
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
 
spacer

• 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
MRI Resources 
Implant and Prosthesis pool - Breast MRI - Raman Spectroscopy - Societies - Absorption and Emission - Health
 
     1 - 5 (of 35)     next
Result Pages : [1]  [2 3 4]  [5 6 7]
 Random Page
 
Share This Page
FacebookTwitterLinkedIn

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



Personalized protocols (age, gender, body habitus, etc.) lead to :
more automated planning 
improved patient comfort 
better diagnostics 
optimized image quality 
nothing 

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. [ 28 March 2024]
Terms of Use | Privacy Policy | Advertising
 [last update: 2024-02-26 03:41:00]