Articles
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36 results found
Article
Reverse Bernheim phenomenon
Reverse Bernheim phenomenon, also known as reverse Bernheim syndrome or reverse Bernheim effect, describes the compromise of left ventricular filling caused by the interventricular septum bulging into the left ventricle. When there is right ventricular pressure and volume overload, the intervent...
Article
MRI in patients with pacemaker systems
MRI in patients with cardiac implantable electronic devices (CIED) has increasingly become a requirement in radiological departments 1-8. Especially in the setting of patients with MR conditional pacemaker systems, where all the manufacturer's instructions are followed and a standardized institu...
Article
Thallium-201 scintigraphy
Thallium-201 (Tl-201) is a radiopharmaceutical used for scintigraphy, primarily of the myocardium. The element thallium is treated by the body as an analog of potassium; it is produced in a cyclotron by bombarding thallium-203 with protons.
Characteristics
thallium is a monovalent cation
usua...
Article
Diastolic pseudogating
Diastolic pseudogating appears as periodic bright and dark signal in arteries such as the aorta as one progresses through a series of images. Synchronisation of the cardiac cycle and the pulse sequence results in high signal in the artery during diastole when blood is relatively stationary and l...
Article
Double oblique multiplanar reconstruction
Double oblique is a type of multiplanar reconstruction used in cardiac cross-sectional imaging. It is useful for an accurate assessment of the ascending aorta and aortic annulus, and is particularly useful for pre- and post-procedure evaluation of a transcatheter aortic valve replacement (TAVR)....
Article
Dimensionless index (DI)
Dimensionless index (DI) is the ratio of the velocity-time integral of the left ventricular outflow tract (LVOT-VTI) to that of the aortic valve jet (AV VTI)1-2.
Dimensionless index (DI) = LVOT VTI / AV VTI
Usage
Dimensionless index is a classic marker of severity in aortic stenosis that does...
Article
Myocardial mapping
Myocardial mapping or parametric mapping of the heart is one of various magnetic resonance imaging techniques, which has evolved and been increasingly used in the last decade for non-invasive tissue characterization of the myocardium 1-5. Unlike normal T1-, T2- or T2*- images, parametric mapping...
Article
Spontaneous echocardiographic contrast (SEC)
Spontaneous echocardiographic contrast (SEC), also known as “echocardiographic smoke” is an echogenic swirling pattern of blood flow created by enhanced ultrasonic back-scatter from clumping of the cellular components of blood in instances of stagnating or low-velocity (low-flow states) 1. It di...
Article
T2* mapping - myocardium
T2* mapping is a magnetic resonance imaging technique used to calculate the T2* time of tissue and display them voxel-vice on a parametric map. It is used for myocardial tissue characterization 1-4 and has been investigated for other tissues 5,6.
Clinical applications
T2* relaxation time has b...
Article
Phase-sensitive inversion recovery
Phase-sensitive inversion recovery (PSIR), also known as phase-corrected inversion recovery (PCIR), refers to an inversion recovery MRI pulse sequence that accounts for the positive and negative polarities and preserves the information of tissue magnetization during the recovery from the initial...
Article
Velocity encoding
Velocity encoding or Venc is referred to as an operator-controlled parameter for the determination of the maximum velocity within a velocity-encoded phase contrast imaging study.
Usage
Velocity-encoding (Venc) gradients are used to generate a phase shift in magnetic resonance phase contrast im...
Article
Cardiac ischemia protocol (MRI)
The cardiac MRI ischemia or stress protocol encompasses a set of different MRI sequences for the assessment of myocardial ischemia.
Note: This article aims to frame a general concept of a cardiac MRI protocol in the setting of vasodilator stress perfusion testing.
Protocol specifics will vary ...
Article
Cardiac tissue characterization
Cardiac tissue characterization is a term for an approach in cardiac imaging used for the evaluation of the myocardial tissue in respect to its inherent properties as opposed to cardiac function e.g. in cine or strain imaging.
In cardiac magnetic resonance imaging tissue characterization typica...
Article
Ammonia (N-13)
13NH3 is a PET tracer used for studies of myocardial perfusion imaging. It is produced in a cyclotron by proton irradiation of the enriched water of the oxygen-16. Ammonia (N-13) is administered intravenously, at a dose of 10-20 mCi (370-740 Mbq) in adults; its physical half-life is 10 minutes.
...
Article
Coronary MR angiography
Coronary MR angiography (coronary MRA) is a developing approach to imaging the coronary arteries.
Advantages of coronary MRA include avoidance of the intravenous iodinated contrast and ionizing radiation used in coronary CT angiography and conventional angiography.
A disadvantage of coronary M...
Article
Extracellular volume - myocardium
Extracellular volume (ECV) refers to the space or volume of a tissue, which is not occupied by cells. Apart from the usual extracellular space, which surrounds the cells of a specific tissue it also includes the intracapillary plasma volume 1,2. It measures the space, which is occupied by the ex...
Article
Bernheim phenomenon
Bernheim phenomenon, also known as the Bernheim syndrome or the Bernheim effect, is the development of right heart failure before left heart failure and has been described in patients with a hypertrophied ventricular septum bulging into the right ventricle, restricting right ventricular diastoli...
Article
Late gadolinium enhancement
Late gadolinium enhancement is a technique used in cardiac MRI for cardiac tissue characterization, in particular, the assessment of myocardial scar formation and regional myocardial fibrosis 1-5.
Terminology
Late gadolinium enhancement is also known under the terms ‘late enhancement’ or ‘dela...
Article
T2 mapping - myocardium
T2 mapping is a magnetic resonance imaging technique used to calculate the T2 times of a certain tissue and display them voxel-vice on a parametric map. It has been used for tissue characterization of the myocardium 1-5 and has been investigated for cartilage 6,7 and other tissues 4.
T2 mapping...
Article
T1 mapping - myocardium
T1 mapping is a magnetic resonance imaging technique used to calculate the T1 time of a certain tissue and display them voxel-vice on a parametric map. It has been used for myocardial tissue characterization 1-6 and has been investigated for other tissues 5.
Terminology
Native T1 is referred t...
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