Although the Siemens Espree 1.5T is a closed-bore system, it is aimed at the open-bore market. Siemens are aiming it at the high-field open system market.

Siemens are also promoting it as their interventional system. It is also suitable for the obese patient.

Magnet

The magnet has a bore diameter of 70 cm, a length of 1.25 m and a field strength of 1.5T. In addition, it is fitted with Siemens' TIM technology, it is therefore being marketed as "70 + 1.25+1.5+TIM".

The distance to the isocentre is 62.5 cm from the bore entrance. The gap from the patient table to the bore top is 55.5 cm.

Siemens state that 60% of clinical scans can be performed feet first giving the patient a 65 degree viewing angle. The control panels and display are at the side of the bore gantry and there is the option to have rear magnet control panels.

The system's mass is 6 tonnes.

The field of view for imaging is 45 x 45 x 30 cm (x, y, z). Hence the FOV is shortest in the z direction.

RF System

The Espree 1.5T is available with 2 options for RF configuration: 76x18 and 32x8 (coil elements x RF channels). The coils are the TIM Matrix coils which are lightweight, weighing just 950 g.

The Espree 1.5T can perform the 205 cm whole body imaging but requires more steps than the Avanto.

Gradients

The gradient system is the Q engine with an amplitude of 33mT/m and a slew rate of 100 mT/m/s. No other gradient options are available for this system.

The Espree does not have the same acoustic noise reduction that the Avanto has.

Applications

The Espree 1.5T incorporates Siemens' standard workflow items i.e. Syngo, Phoenix, In-line processing and Auto-Align.

It has all clinical packages that are available on the Avanto.

It is good for spine imaging and is designed so that the new spine loading devices can be used.

Siemens launched the new version of the Trio 3T.

It will be available for delivery from December 2005.

Magnet

The new Trio 3T system incorporates the same magnet design. Siemens has opted to maintain this, rather than use a new design with a shorter bore, to maintain the homogeneity advantage that the Trio magnet has.

It has a 50cm field of view and has a homogeneity of 0.25ppm over a 40cm DSV.

RF

The new Trio 3T incorporates Siemens' TIM technology and comes with two options either 76x18 or 76x32 (coil elements x RF channels).

The Trio has the iPAT2 option with iPAT factors of up to 16. At 3T, iPAT is very useful to reduce the SAR and hence avoid issues with heating and exposure limits.

A big advantage with the TIM system is that the coils for 3T are now Siemens coils. However for fMRI, coils from the independent manufacturers will still be required.

Currently in development are a 32-channel head coil and a multi-channel cardiovascular coil.

Gradients

The new Trio 3T incorporates a new gradient system. It has the same specifications as before, but has a new design.

Upgrade path

Existing Trio 3T systems can be upgraded to the new version. The magnet is retained, but the system requires new gradients, a new RF system and new magnet covers.

The Magnetom Avanto 1.5T was unveiled at last year's meeting in 2003. It continues to be showcased this year, however, and for completeness, we have reproduced the system features.

Whole Body Imaging

Siemens' Total Imaging Matrix (TIM) technology, allows whole-body imaging of patients up to 205cm in height within a single examination.

Magnet

New magnet technology provides greater homogeneity of the static magnetic field.

The improved "cold head" has also virtually eliminated cryogen boil-off. The time between refills is now estimated to exceed 10 years.

Parallel Imaging

Siemens parallel imaging technology (IPAT) now operates at up to factor 12.

Their extended, 3D parallel imaging system, IPAT², now allows parallel imaging in 3 gradient directions.

Gradients

The gradients systems have been redesigned and now provide extended coverage of 50cm.

New noise reduction techniques are also employed, giving maximum noise levels of 99dbA.

The two gradient speed options are the QEngine, with a strength of 33mT/m and slew rate of 125mT/m/s and the SQEngine, with a strength of 45mT/m and slew rate of 200mT/m/s.

The gradient redesign also counteracts the peripheral nerve stimulation of the Sonata gradient systems.

Siemens also are offering the Concerto 0.2T and the Magnetom C 0.35T.

The Magnetom C 0.35T does not have TIM but uses multiple-channel matrix coils with 2 or 4 channels.

Whole body imaging with constant table movement is in development.