| Info Sheets |
| | | | | | | | | | | | | | | | | | | | | | | | |
| Out- side |
| | | | |
|
| | | | | | | Searchterm 'AIN' was also found in the following services: | | | | |
| | |
| |
|
MS-325 is the formerly code name of gadofosveset trisodium (new trade name Vasovist). MS-325 belongs to a new class of blood pool agents for magnetic resonance angiography ( MRA) to diagnose vascular disease. Gadofosveset trisodium has ten times the signal-enhancing power of existing contrast agents as well as prolonged retention in the blood. This enables the rapid acquisition of high resolution MRA's using standard MRI machines.
Gadofosveset trisodium, which is gadolinium-based, stays in the blood stream as a result of transient binding to albumin. Albumin binding offers an additional benefit beyond localization in the blood pool. The contrast agent begins to spin much more slowly, at the rate albumin spins, causing a relaxivity g ain that produces a substantially brighter signal than would be possible with freely circulating gadolinium.
MS-325 is an intravascular contrast agent intended for use in MRI as an aid in diagnosing aortoiliac occlusive disease in patients with known or suspected peripheral vascular disease (PVD) or abdominal aortic aneurysm (AAA).
Currently clinical trials completed for peripheral vascular disease and coronary artery disease. Additional trials are also being conducted to evaluate MS-325 as an aid in diagnosing breast cancer and suggested that it might be feasible to combine the use of MS-325, injected during peak stress, with delayed high-resolution imaging to identify myocardial perfusion defects.
Vasovist (MS-325) would compete with the contrast agents Ferumoxytol ( Code 7228) from AMAG Pharmaceuticals, Inc. and NC100150 Injection from Nycomed Amersham, but their further development is uncert ain.
Partners in development: EPIX Pharmaceuticals, Inc., Mallinckrodt Inc., and Bayer Schering Pharma AG. Bayer Schering Pharma has the worldwide marketing rights for the product.
Formerly known under the Mallinckrodt trademark name, AngioMARK®.
See also Classifications, Characteristics, etc. | | | | • View the NEWS results for 'MS-325' (10).
| | | | Further Reading: | News & More:
|
|
| |
| | | | | |
| |
|
Quick Overview Please note that there are different common names for this artifact.
DESCRIPTION
Striped ghosts with a shift of half the field of view
Machine imperfection-based artifacts manifest themselves due to the fact that the odd k-space lines are acquired in a different direction than the even k-space lines. Slight differences in timing result in shifts of the echo in the acquisition window. By the shift theorem, such shifts in the time dom ain data then produce linear phase differences in the frequency dom ain data.
Without correction, such phase differences in every second line produce striped ghosts with a shift of half the field of view, so-called Nyquist ghosts. Shifts in the applied magnetic field can also produce similar (but constant in amplitude) ghosts.
This artifact is commonly seen in an EPI image and can arise from both, hardware and sample imperfections.
A further source of machine-based artifact arises from the need to acquire the signal as quickly as possible. For this reason the EPI signal is often acquired during times when the gradients are being switched. Such sampling effectively means that the k-space sampling is not uniform, resulting in ringing artifacts in the image.
Image Guidance
Such artifacts can be minimized by careful setup of the spectrometer and/or correction of the data. For this reasons reference data are often collected, either as a separate scan or embedded in the imaging data.
The non-uniform sampling can be removed by knowing the form of the gradient switching. It is possible to regrid the data onto a uniform k-space grid. | | | | • View the DATABASE results for 'Machine Imperfection Artifact' (2).
| | | | Further Reading: | Basics:
|
|
| |
| | | | | |
| |
|
Quick Overview
DESCRIPTION
Increase of the T2 time, bright signal in tendons
The magic angle is a precisely defined angle, the value is approximately 54.7°. Hence, two nuclei with a dipolar coupling vector at an angle of approximately 54.7° to a strong external magnetic field have zero dipolar coupling.
Magic angle spinning is a technique in solid-state NMR spectroscopy, which employs this principle to remove or reduce dipolar couplings, thereby increasing spectral resolution.
In MRI, the magic angle effect visualizes as bright spots through an increased T2 time on short echo time (TE) images, for e.g. collagen fibers of tendons and ligaments, which are oriented at the magic angle of approximately 54.7° to the magnetic field.
Image Guidance
Take care that tendons and ligaments are not oriented at about a 54.7° angle to the m ain magnetic field. | | | | | Further Reading: | Basics:
|
|
| |
| | | Searchterm 'AIN' was also found in the following services: | | | | |
| | |
| |
|
A magnet is by definition an object with magnetic properties ( magnetism) that attracts iron and produces a magnetic field. It can be a permanent magnet or an electromagnet.
Permanent magnets do not rely upon outside influences to generate their field. In permanent magnets are the atoms and molecules ordered in long range. The specific electron configuration and the distance of the atoms is what lead to this long range ordering. The electrons exist in a lower energy state if they all have the same orientation. Magnetic dom ains can be likened to microscopic neighborhoods in which there is a strong reinforcing interaction between particles, resulting in a high degree of order. The greater the degree of ordering within and between dom ains, the greater the resulting field will be. Long range ordering is one of the hallmarks of a ferromagnetic material.
A current carrying conductor for example a piece of wire, produces a magnetic field that encircles the wire. An electromagnet, in its simplest form, is a wire that has been coiled into one or more loops. This coil is known as a solenoid. The more loops of wire and the greater the current, the stronger the field will be.
Superconducting magnets are a special type of electromagnets, often used in MRI machines with high field strength. | | | | • View the DATABASE results for 'Magnet' (669).
| | | • View the NEWS results for 'Magnet' (315).
| | | | Further Reading: | | Basics:
|
|
News & More:
| |
| |
| | | | | |
| |
|
(MSI) The combination of biomagnetic field detection and MR imaging into a merged data set. Most applications of MSI involve the combined use of MRI and measurement of magnetic fields created by electric currents in the brain, so-called magnetoencephalography MEG.
MEG allows calculation of the source of the measured biomagnetic fields, and thereby localization of many regional brain functions, such as mapping of the sensorimotor, auditory and visual cortex and also localization of epileptogenic foci.
The MEG coordinate system is defined by anatomical landmarks, which are easily identified also with MRI, making it possible to align the 3D MEG data with the 3D MR image data. The resulting magnetic source images show the spatial relationships between the functional area provided by MEG and the neighboring anatomy and pathology, both provided by MRI.
Cardiac applications of MSI are also being explored. The electric currents in the myocardium create extrathoracic magnetic fields and the source of these fields may be calculated by the same principles as those used in MEG. Possible cardiac applications include mapping of arrhythmogenic sites prior to ablation therapy. | | | | • View the DATABASE results for 'Magnetic Source Imaging' (2).
| | | • View the NEWS results for 'Magnetic Source Imaging' (2).
| | | | Further Reading: | News & More:
|
|
| |
| | | | |
| | | |
|
| |
| Look Ups |
| |