MRI Injector Power Supply, MR Conditional Labelling and Placement

MR Safe, MR Conditional and MR Unsafe

Standard MR safety terminology (ASTM F2503) classifies devices as MR Safe, MR Conditional or MR Unsafe. An MR conditional injector has been shown to pose no known hazard in a defined MR environment under stated conditions, for example a maximum static field strength, a maximum spatial field gradient or a restriction on where in the room the unit may stand. These conditions are given in the device labelling and instructions for use.

Ask the supplier for the MR labelling of the exact model, not just the family, and compare the stated conditions with your scanner. If a condition is unclear, request written clarification from the manufacturer before ordering.

Zones and positioning in the magnet room

MRI departments are usually divided into four access zones, with the magnet room as the most restricted. A mri injector in magnet room use must be positioned according to its conditions: often this means that it can stand in the room but must stay beyond a marked line or distance from the bore, and must not be left unattended where it could be drawn toward the magnet.

Mark the permitted parking position on the floor, train all staff, and make it part of the room rules. The injector terminal and the staff operating it are commonly in the control room or the technician area, depending on the system.

Include the injector in your emergency planning. Staff should know how to remove the unit from the magnet room quickly and safely if a patient needs urgent help, and where it must never be taken. Rehearse this in the same drills you use for other MR equipment.

• Check the maximum field strength in the labelling
• Mark the permitted position with floor tape or a line
• Never move the unit toward the bore if its labelling does not allow it
• Include the injector in the MR safety screening procedure

Power supply and cordless injectors

Mains cables across a magnet room are a nuisance and, near the bore, a risk. A cordless design removes them. The ulrich medical Max 3 and Max 2M run on battery and communicate with the terminal by Wi-Fi, which keeps the room free of cables. Both are compact units of about 40 kg on a four-caster base (530 × 530 × 1,372 mm).

A cordless MRI injector battery needs a routine: charge between lists, monitor run time and plan for replacement as it ages. Ask the supplier what happens when the battery is low, how the user is warned and whether charging can be done outside the magnet room. Request the details from the manufacturer's documentation rather than relying on general statements.

Wi-Fi in an MRI suite also needs thought. The link between terminal and injector should be tested in the actual room, and the supplier should state which radio-frequency band is used so that your MR physicist can confirm that it does not interfere with imaging.

What to put in the purchase documents

Include in the specification the MR labelling and conditions, the maximum field strength supported, the battery and charging arrangement, the Wi-Fi requirements and any restrictions on positioning. Ask the supplier to supply the instructions for use in advance so your MR safety officer can review them.

For other considerations, see our Max 3 overview, the compact Max 2M article and the MRI injector price guide, which lists what to include in quotation requests.

Next steps

Beckfinity can provide the documentation for ulrich medical MRI injectors and help you plan placement in the magnet room; contact our specialists for a quote or consultation. Your MR safety officer or medical physicist should approve the final arrangement.