From Siemens Medical Systems;
Received FDA clearance in 2007.
The MAGNETOM Verio provides up to 102 integrated matrix coil elements and up to 32 independent radiofrequency channels that allow flexible coil combinations to make patient and coil repositioning virtually unnecessary. The Tim (total imaging matrix) technology also increases patient throughput due to a shorter scan time.
The open bore design offers great comfort for patients of all shapes and sizes.

System for actively cooling structures in a superconducting magnet. If only cryoshields are cooled (two-stage refrigerator), no liquid nitrogen will be needed and He boil off will be reduced. If additionally the superconducting coil support is actively cooled (three-stage refrigerator) the He-consumption can be essentially reduced to zero.

See also Boil off Rate.

From Hitachi Medical Systems America Inc.;
Hitachi expanded its portfolio with the Echelon™ 1.5T. The MRI scanner combines a compact magnet and a scalable 8-channel RF system with high-performance gradients and slew rate to select short echo times, small field of views, high matrices and thin slices. Standard features of the Echelon MRI system include higher-order active shim, RAPID (parallel imaging for use on brain MRI, body, cardiovascular imaging, and orthopedic coils), multiple coil ports, and an advanced reconstruction engine.

Quenching is the cryogen boil off (liquid helium) which is used to cool the superconducting magnet coils of high field MRI systems. This results in a loss of superconductivity in the magnet, in a rapid increase in the resistivity of the magnet, which generates heat that results in further evaporation of the cryogen.

A quench can cause total magnet failure and should be avoided.

Superconducting magnets are electromagnets that are partially built from superconducting materials and therefore reach much higher magnetic field intensity.
The coil windings of superconducting magnets are made of wires of a type 2 superconductor (mostly used is niobium-titanium - up to 15 Tesla the critical temperature is less then 10 Kelvin). These coils have no resistance when operated at temperatures near absolute zero (-273.15°C, -459°F, 0 K).
Liquid helium (4.2 K) is commonly used as a coolant (sometimes in addition with a second cryogen liquid nitrogen as an intermediate thermal shield to reduce the boil-off rate of liquid helium), which consequently conclude refilling (intervals: liquid helium ~ 3 month, liquid nitrogen ~ 2 weeks). There are cryogen-free superconducting magnets with a closed-cycle refrigerating system at the horizon. Superconducting magnets typically exhibit field strengths of greater than 0.5 T, operate clinically up to 3 T, and have a horizontal field orientation, which makes them prone to missile effects without significant magnetic shielding.
See also Quenching.

See also the related poll result: 'In 2010 your scanner will probably work with a field strength of'