Short name: MION, central moiety: Fe3+/Fe2+, relaxivity: r1=3.7, r2=6.5, B0=0.47T
MIONs are under development (preclin.) as contrast agents (taken up by the RES) for MR angiography, MR lymphography, tumor detection and detection of infarctioned tissue. Also called monodisperse iron oxide nanoparticles or nanocompounds.

(MC) Multiple 3D Volumes (chunks) joined together in 1 scan. Used for 3D TOF angiography. 3D TOF MRA is acquired with 3D FT slabs or multiple overlapping thin 3D FT slabs depending on the coverage required and the range of flow-velocities under examination.
Also called multiple overlapping thin slab slice acquisition (MOTSA) or multi slab.

(MOTSA) This technique combines the best features of 2D time of flight angiography (2D TOF) and 3D TOF MRA. The MOTSA technique consists of multiple 2 cm thick 3D TOF slabs (which minimize saturation effects for through plane flow) combine to provide unlimited coverage similar to multiple 2D TOF slices. High resolution imaging of the carotid arteries is possible when image quality is of greater concern than acquisition time. Images with 1 mm (or less) spatial resolution in all three planes are required. The slabs typically overlap 25-40 to minimize the venetian blind artifact venetian blind artifact due to minimal saturation effects. MOTSA is an useful technique for the evaluation of vertebrobasilar ischemia and aneurysm scanning from the foramen magnum through the circle of Willis.

The navigator technique measures with an additional quick MR prepulse the position, of e.g. the diaphragm before data collecting. Similar respiratory conditions of the patient can be identified and used to synchronize image data acquisition so that respiration induced image blurring is minimized by either respiratory ordered phase encoding or respiratory gating.
The prepulse sequence images a small area perpendicular to the structure, which is moving. The contrast of the interface between the diaphragm and the lung should be high to permit easy automatic detection. After data acquisition, the position of the interface is automatically recorded and imaging data are only accepted when the position of the interface falls within a range of prespecified values.
This technique has the advantage of greater accuracy than other respiratory gating (therefore used for coronary angiography) and has no need for additional sensing MRI equipment, as the MR system itself provides it.

From Toshiba America Medical Systems Inc.;
OPART™ is a 0.35 T superconducting open MR system featuring cryogenless operation. Superconducting speed and performance are combined with the patient access advantages of open MRI design for unmatched clinical versatility. OPART™ features innovative technologies such as digital RF, high speed gradients and optimized RF coils, which support advanced MRI applications.