by
Sean Ruck, Contributing Editor | September 16, 2015
From the September 2015 issue of HealthCare Business News magazine
HCBN: Why does an RF shield no longer meet specifications?
Dave Geiger, ETS Lindgren: There are many reasons. It could be building settlement, corrosion in the shield, wear and tear in the door, moisture buildup due to condensation or leaky pipes, and due to other construction workers in the area who may have been physically in contact with the shield after it was installed.
HCBN: What should someone look for in a shield upgrade? For instance, if they were upgrading from just an RF shield, should a magnetic shield be included?
Diego Copa, SDI Worldwide: The steps are similar to the ones they should follow for reusing an existing shield. The first step to an upgrade is what we call a baseline test — this allows clients to determine the current state of the shielding system in question. A baseline test is usually performed by a shielding vendor or a specialized testing firm.
The test provides the results in dB and must be performed in accordance with the future magnet attenuation specifications. A properly executed baseline test includes some minor troubleshooting in order to provide the client with the scope of work required to achieve a suitable upgrade for the new magnet.
Mike Profeta: When swapping out equipment, the existing MRI room will be tested for shielding effectiveness. Ironically, after all the work, decisions, and testing for when the shield was first built, most of the time its effectiveness has not ever been measured again until the replacement magnet is on its way. It is now that the customer finds out the shield fails miserably and they have potentially been dealing with somewhat compromised images. Perhaps noisier than normal or intermittent artifacts or a whole mirage of compromises that over the years have become the norm.
HCBN: What should customers look for when selecting an MR vendor?
Carly Holloway and Onofrio Losito: Having a wealth of knowledge and technical support is a key component to look for when choosing a shielding vendor. Can they tell what the problem is from a DICOM file, or do they have to go through a list of troubleshooting? The size of the company is also important and can sometimes affect how quickly they can get to a site. If their engineers are at a site installing a shield, how many days will it take them to send someone to service yours? Has the company you are purchasing from been in business for many years or is it just starting out? This is something to consider when looking at warranties of an RF shield — it is great to have a five-year warranty as long as the company will not be out of business by then.
