The owner of MRI equipment has to ensure that the equipment does fulfill the local requirements.
In some countries, the requirements are more stringent than in others; in other countries, they are nonexistent.
The user in general is unable to check power output, gradient strength, or even field strength. The manufacturer has to cover authorized hardware and software updates after the initial installation and has to give guarantee for the requirements. Specially designed computer programs usually supervise the power output of MRI devices and will not allow or will interrupt any imaging or spectroscopy procedure exceeding those limits considered safe.

See also European Medicines Agency, FDA information:
www.fda.gov/cdrh/safety/mrisafety.html

From Siemens Medical Systems;
the 3 T MAGNETOM Allegra is a dedicated MR headscanner, perfect as a research system in cognitive and neuroscience with MRS and fMRI. MAGNETOM Allegra is a full member of the MAGNETOM product family. It uses many common components, i.e. electronics, computer system, software and pulse sequence concepts.

Possible MR guided interventions are breast MRI, liver and bone biopsies. Open MRI is advantageous to guide interventional procedures because this type of MRI scanner provides a better patient access.
Before the MRI guided biopsy is started, all the necessary precautions ensuring normal sterile and safe conditions for an intervention have to be performed. This includes the special safety issues concerning MRI surroundings and special equipment, like non-magnetic biopsy needles, localization tools (e.g. wires to mark lesions prior to surgery with breast MRI guidance) etc.

See also 5 Gauss Line, Contraindications, Low Field MRI, MR Compatibility, Magnetic Resonance Guided Focused Ultrasound and Computer Aided Detection.

The MRI equipment consists of following components:
Better MRI equipment and software design along with the latest information technology improves system maintenance and overall communication. Software and digital imaging and communications in medicine (DICOM) compatibility allows to network into hospital databases, helps to modify pulse sequences, data post processing, and archiving via picture archiving and communication system (PACS).

See also the related poll result: 'Most outages of your scanning system are caused by failure of'

(MRA) Magnetic resonance angiography is a medical imaging technique to visualize blood filled structures, including arteries, veins and the heart chambers. This MRI technique creates soft tissue contrast between blood vessels and surrounding tissues primarily created by flow, rather than displaying the vessel lumen. There are bright blood and black blood MRA techniques, named according to the appearance of the blood vessels. With this different MRA techniques both, the blood flow and the condition of the blood vessel walls can be seen. Flow effects in MRI can produce a range of artifacts. MRA takes advantage of these artifacts to create predictable image contrast due to the nature of flow.
Technical parameters of the MRA sequence greatly affect the sensitivity of the images to flow with different velocities or directions, turbulent flow and vessel size.
This are the three main types of MRA:
All angiographic techniques differentially enhance vascular MR signal. The names of the bright blood techniques TOF and PCA reflect the physical properties of flowing blood that were exploited to make the vessels appear bright. Contrast enhanced magnetic resonance angiography creates the angiographic effect by using an intravenously administered MR contrast agent to selectively shorten the T1 of blood and thereby cause the vessels to appear bright on T1 weighted images.
MRA images optimally display areas of constant blood flow-velocity, but there are many situations where the flow within a voxel has non-uniform speed or direction. In a diseased vessel these patterns are even more complex. Similar loss of streamline flow occurs at all vessel junctions and stenoses, and in regions of mural thrombosis. It results in a loss of signal, due to the loss of phase coherence between spins in the voxel.
This signal loss, usually only noticeable distal to a stenosis, used to be an obvious characteristic of MRA images. It is minimized by using small voxels and the shortest possible TE. Signal loss from disorganized flow is most noticeable in TOF imaging but also affects the PCA images.
Indications to perform a magnetic resonance angiography (MRA):
Conventional angiography or computerized tomography angiography (CT angiography) may be needed after MRA if a problem (such as an aneurysm) is present or if surgery is being considered.

See also Magnetic Resonance Imaging MRI.