Infection Control in the MRI Environment*

The magnetic resonance (MR) imaging environment is a complex and potentially dangerous setting with respect to issues involving infection control, particularly because custodial personnel and routine cleaning equipment are not permitted to enter this area without adhering to strict policies and procedures. Importantly, cleaning the MR system room is often the responsibility of the MR system operator, who is rarely trained or certified in infection control. Therefore, it is unreasonable to believe that the MRI environment, especially the MR system and associated accessories (e.g., inside the bore of the scanner, surface coils, the positioning pads/sponges, patient management devices, etc.), can be cleaned safely and effectively by untrained personnel. This important task requires specialized written procedures and proper training.

Patients with serious infections may undergo diagnostic imaging during the course of their treatment. There is frequently a lack of special procedures for managing highly contagious patients, particularly at outpatient imaging centers and mobile MR scanners. Contagious patients may simply be placed on the MR system table and scanned, while the next patient, possibly an immunosuppressed child with a sprained knee, is put on the table directly after this infected patient without properly cleaning the table, pads, and sponges. Obviously, this is a serious situation that deserves attention. Therefore, all MRI facilities must take appropriate action to ensure that the MR environment is not a site for exposing patients and healthcare workers to microorganisms that are capable of causing infectious diseases.

At many MRI centers, there is a misconception that merely placing a clean sheet over the scanner table, without actually cleaning the mattress between patients, will prevent the spread of infectious agents. Of note is that placing clean sheets on a contaminated surface may contaminate the sheets and pose further infectious risk when the sheets are handled. Of further concern is that very few MRI facilities clean inside of the bore of the MR system on a regular basis. Positioning pads and sponges may only be cleaned once a day.

There is also the issue of potentially spreading infectious agents by direct or indirect contact among the imaging staff and patients within the imaging facility. For MR systems in mobile facilities, ensuring proper hygiene is often more difficult, since these sites may not have a sink or running water. Therefore, hand-washing between patients as well as using hand sanitizer regularly is of crucial importance.

Another overlooked area is the presence of torn or frayed positioning pads, sponges, and scanner table mattresses used in association with MRI examinations. Once the covering material has been breached, the surfaces of these items cannot be properly cleaned and should be immediately removed and replaced. It is well known that, if disinfected, a smooth surface can be repeatedly used without problems. However, for items with a porous surface (e.g., those made from “spongy” materials), the presence of infectious agents, including Methicillin-resistant Staphylococcus aureus, MRSA, can be detected even after performing disinfection. Thus, porous surfaces made of such materials cannot be adequately cleaned and disinfected.

Protecting patients and staff takes a concerted effort by all parties involved in the MRI facility. There is no question that infection control has not received the attention that it deserves and there is a growing concern that at least some of the spread of infectious agents could be coming from outpatient imaging centers and radiology departments in hospitals.

The following recommendations are provided for MRI facilities to address infection control standards that are used throughout the healthcare industry:

Recommendations for Infection Control in the MRI Environment

1. Create a written infectious control policy to include cleaning procedures for the MRI environment, as well as a cleaning schedule, and have it posted throughout the center.
2. Implement a mandatory hand-washing / hand-sanitizing procedure between each patient not only for MRI healthcare workers, but also for others who come into contact with patients.
3. Clean the MR scanner table, the area inside the bore of the MR system, and all items that come into contact with the patient. Infection control experts recommend that the cleaning procedure should be performed between patients.
4. Clean all positioning pads and sponges with an approved disinfectant. Infection control experts recommend cleaning after each patient.
5. Periodically inspect the pads with a magnifying glass, particularly at the seams, to identify fraying or tearing. Replace the pads, as needed.
6. Use pillows with a waterproof covering that is designed to be surface wiped. Replace pillows when this barrier is compromised.
7. Promptly remove body fluids and then disinfect all contaminated areas.
8. If the patient has an open wound or history of infection, especially related to MRSA, gloves and gowns must be worn by all staff members coming into contact with the patient. These barriers must be removed before touching other areas that do not come in contact with the patient (e.g., door knobs, scanner console, computer keyboards, etc.).
9. The scanner table, positioning sponges, and pads should be completely cleaned with disinfectant before the next patient is scanned, if this procedure is not already being performed between each patient. For patients with any known infectious process, add 10-15 minutes to the scheduled scan time to ensure that there is enough time to thoroughly clean the room and patient-related surfaces.
10. All furniture should be periodically cleaned. Ideal surfaces are those that are waterproof, nonporous, and easy to clean. Infection control experts recommend that such cleaning be performed between patients.

Content excerpted with permission provided by Peter Rothschild, M.D. Louisville, KY. Reviewed and updated 2016.

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