MRI vendor suite templates: What they don't show

Emergency exhaust: A crucial backup to the cryogen vent, the emergency exhaust fan can quickly evacuate cryogen vapors that may back up into the room in the event of a quench. Though emergency exhaust systems are referenced once or twice in multipage siting material, their layout isn't included in the templates of many vendors. Incorrect design or positioning of emergency exhaust or transfer grille components by design professionals can render these safety features useless, or even increase certain hazards.

Cryogen vent discharge: Vendors do include cryogen vents in their templates, but most don't graphically depict the recommended safety clearances at the point of discharge. These safety clearances apply not only to persons who may be in the area of discharge, but also to serviceable equipment, air intakes, or operable windows that may be near the cryogen vent or emergency exhaust discharge locations.

ACR four-zone patient screening: Magnetic field hazards aren't limited to the magnet room, and patient screening prior to entering the high-strength magnetic field is vital. Yet magnet vendors only provide the magnet room, control room, and equipment room in their templates, without even so much as a disclaimer to safety and operational issues that extend beyond these three rooms and perhaps outside the building. Those are left to facility operators and their design professionals.

Image quality: Generic vendor templates define the maximum allowable ferrous content for shimming thresholds, but don't explain that "operational tolerances" and "optimal image quality" can be miles apart. If an MRI installation is expected to provide top-quality images five or 10 years from now, then every effort should be taken to design the suite that will protect the quality of the clinical image and extend the useful life of the MRI.

Patient throughput: A magnet may make a cluster of rooms into an MRI suite but, by itself, it doesn't do anything to maximize efficiency and operational ease. Effective layout of support spaces (patient waiting, interview, screening, changing, holding, and so on) is vital to an efficient and effective patient flow. Focusing only on the magnet, control, and equipment rooms does nothing to provide an effective patient flow. Particularly with reduced reimbursements, suite efficiency and patient throughput are vital to the financial performance of a facility.

Upgradeability: When magnet room construction costs run more than $250 per square foot, it only makes sense to ensure that the building is suitable to support the next generation of magnets. Rooms built to the minimum specifications of many current vendor templates for 1.5-tesla systems would have a very hard time being adapted to support that same vendor's 3-tesla MRI units. Why build a suite that will require a couple hundred thousand dollars in renovations to support the next upgrade when you can now add the incremental room size or shielding at a fraction of the future costs?

Lines of sight: Many vendors show the console with a view into the bore of the magnet, but no information is provided about laying out the suite so that the technologist at the console also has direct lines of sight to the magnet room door, its approach, and, if possible, the patient holding area. In many MRI facilities, the technologist is the person principally responsible for patient safety throughout the MRI suite. How are they to monitor the activity and safety of patients anywhere other than inside the bore of the magnet if that's the only view they're afforded from the console?

Patient specific: Templates are, by definition, a "one-size-fits-all" solution. But patient populations and magnet use differ from facility to facility. Facilities that perform scans on patients under general anesthesia, treat only pediatric patients, or scan only emergent patients have vastly different room needs than a dedicated outpatient facility. Templates don't address those variables.

We trust them too much: Well, this is really a problem with us and not vendor templates. Templates do have a lot of very valuable information and can greatly facilitate siting an MRI. However, there is a vast amount of information that facility operators, technologists, administrators, engineers, and architects must bring to the design to have truly safe, effective and efficient suites.