MRIS 101- CH4-7

In the ACR MR safety framework, how are 'MR Personnel' defined?

MR Personnel are individuals who have been formally educated and trained in MR safety topics (as defined by the facility's MRMD) to ensure they do not represent a danger to themselves or others in the MR environment.

Who is classified as 'Non-MR Personnel'?

Non-MR Personnel include patients, accompanying companions, and healthcare staff (including non-trained physicians and technologists) who have not met the facility's formal MR safety education requirements.

What defines 'Level 1 MR Personnel'?

Level 1 MR Personnel are individuals who have passed basic MR safety training to ensure they will not pose a hazard to themselves or others while working in Zone III and Zone IV.

What defines 'Level 2 MR Personnel'?

Level 2 MR Personnel are extensively trained in broader MR safety issues (such as RF thermal burns, gradient-induced PNS, and static field forces). They are authorized to supervise Level 1 personnel and Non-MR Personnel in Zone III and Zone IV.

Which clinical roles are required to hold Level 2 MR Personnel status?

• MR Technologists • MR Radiologists / MR Physicians

What are the primary responsibilities of the MR Medical Director (MRMD)?

1. Oversee overall operational safety of the MR facility. 2. Appoint the MR Safety Officer (MRSO) and advisory MR Safety Expert (MRSE). 3. Establish, maintain, and enforce facility MR safety policies and SOPs. 4. Ensure appropriate MR safety training for all personnel. 5. Investigate, document, and report MR safety-related adverse events.

What are the primary responsibilities of the MR Safety Officer (MRSO)?

1. Ensure day-to-day enforcement of MR safety policies established by the MRMD. 2. Remain accessible to scanner operators whenever the facility is in use. 3. Oversee equipment marking, testing, and tethering in Zone III and Zone IV. 4. Monitor safety measures, manage environmental hazards, and assist in root-cause analyses.

What is the primary role of the MR Safety Expert (MRSE)?

The MRSE serves as an off-site or on-site expert resource for technical, scientific, and physics-related MR safety matters (such as spatial field gradient evaluations and complex implant safety calculations).

What safety rule applies when Non-MR Personnel enter Zone III or Zone IV?

Non-MR Personnel must be screened and directly accompanied, monitored, and supervised by Level 2 MR Personnel at all times while in Zone III and Zone IV.

What requirement must be met to hand off supervisory responsibility for Non-MR Personnel in Zone III/IV?

There must be a formal, explicit transfer of safety responsibility from one Level 2 MR Personnel to another Level 2 MR Personnel who fully accepts the responsibility.

What minimum staffing model is required when employing remote MR scanning technology?

A minimum of 3 MR Personnel is required: 1. Remote Level 2 MR Technologist (operates scanner remotely). 2. On-site Level 2 MR Technologist (dedicated to patient screening, positioning, and safety). 3. On-site Level 1 or Level 2 MR Personnel (assists with patient monitoring and emergency response).

What critical responsibilities must the on-site Level 2 MR Technologist handle during remote scanning?

1. Perform history and physical MR safety screening. 2. Research implanted devices. 3. Position the patient and apply burn prevention insulation/padding. 4. Select, place, and plug in the proper RF coils. 5. Respond immediately to patient distress, emergencies, or contrast reactions.

What contingency plan must be included in SOPs for remote MR scanning?

Clear provisions must be established to ensure patient safety if the remote network connection is interrupted or lost during an ongoing scan.

What is the primary purpose of MR safety screening?

To prevent accidental introduction of ferromagnetic projectiles, avoid unsafe exposures of implanted/on-planted medical devices, prevent RF burn injuries, and protect all individuals entering Zone III and Zone IV.

What strict rule applies to answering questions on an ACR MR Safety Screening Form?

No blank or empty responses are permitted. Every question must be explicitly answered with 'Yes' or 'No', or detail provided as requested.

What are the components of a multi-tiered MR screening program?

1. Referring physician order set screening questions. 2. Pre-screening questions during scheduling. 3. Written or electronic screening questionnaire. 4. Direct, interactive verbal screening by Level 2 MR Personnel.

How many times must a conscious nonemergent patient be screened prior to Zone IV entry?

At least twice prior to entering Zone IV, with at least one screen performed interactively/verbally by Level 2 MR Personnel.

What special screening requirement exists for pediatric or minor patients?

They must be screened twice by Level 2 MR Personnel, with one screening conducted separately from their parents or guardians.

How must an unconscious or altered-consciousness patient be screened for MRI?

1. A family member, legal guardian, or healthcare proxy completes the written questionnaire and verbal interview. 2. Objective physical screening (e.g., visual inspection, plain radiographs, or FMDS) is used to detect unknown foreign bodies or active/passive implants.

Under what conditions may an unscreened emergent patient enter the MR environment?

Only in extenuating circumstances where delay risks death or permanent disability, AND with explicit mutual agreement between the ordering physician and covering Level 2 MR Physician / MRMD acknowledging the risks of skipping screening.

What screening requirements apply to patient companions entering Zone IV?

• Must complete an abbreviated safety screening form. • Must be screened for ferromagnetic objects. • Must be provided and wear hearing protection while in Zone IV.

What is the policy for staff and personnel MR safety screening?

• Initial onboarding MR safety screening prior to entering Zone III/IV. • Mandatory annual review of safety screening. • Immediate reporting of any change in medical status (e.g., new implant) to the MRMD before returning to Zone III/IV.

Who makes the final decision on whether to proceed with an MR examination for a high-risk or complex patient?

The Level 2 MR Physician or MRMD makes the final determination based on a risk-versus-benefit assessment.

What is the recommended role of Ferromagnetic Detection Systems (FMDS) in MR screening?

FMDS should be used as an effective adjunct to written and verbal screening to detect concealed ferromagnetic materials before entering Zone IV.

Why are conventional hand-held or walk-through metal detectors NOT recommended for MR screening?

Conventional metal detectors detect all metals (ferrous and non-ferrous) non-specifically, frequently alarm on non-hazardous items, and can miss small, highly dangerous ferromagnetic objects, creating a false sense of security.

What are the patient gowning requirements prior to entering Zone IV?

Patients must remove all street clothing, undergarments, and metallic accessories, and change into site-supplied MR Safe pocketless gowns/garments covering the RF irradiation zone.

According to MR safety protocols, why must items like those shown in the image be removed before entering Zone IV?

These items present serious MR risks: 1. Projectile risks (keys, cell phones, hair clips). 2. RF burn & induced current risks (hearing aids, CGMs, smart rings, hand warmers). 3. Device malfunction or destruction (insulin pumps, CGMs, electronic keys).

What is the 'Full Stop / Final Check' process?

A mandatory pause performed immediately before crossing the boundary from Zone III into Zone IV to confirm complete safety screening and remove all undetected metallic or electronic hazards.

What is the difference between a Routine and an Augmented Full Stop / Final Check?

• Routine: Used in ambulatory settings with no extra support equipment. • Augmented: Used in complex settings (inpatient, emergent, anesthesia, interventional) involving support equipment, monitors, lines, and transport personnel.

Who performs the Routine Full Stop / Final Check, and when is it executed?

It is performed by the Level 2 MR Technologist immediately prior to permitting the patient, accompanying personnel, or equipment to pass from Zone III into Zone IV.

What verification elements are included in the Routine Full Stop / Final Check?

1. Confirm patient identity and completed screening forms. 2. Verify removal of hearing aids, CGMs, external pumps, hair pins, keys, and cell phones. 3. Inspect support equipment for concealed ferrous items. 4. Identify contrast injection access line/port. 5. Ensure required equipment in Zone IV is tethered. 6. Re-confirm patient/equipment status has not changed in Zone III.

Why must external devices like CGMs, hearing aids, and insulin pumps be removed before entering Zone IV?

• Static magnetic fields ($B_0$) can damage electronic circuits or cause displacement. • Gradient fields ($dB/dt$) and RF fields ($B_1$) can induce electrical currents, causing thermal burns or device failure.

What equipment check must be conducted during an Augmented Final Check for ICU or anesthesia transfers?

Inspect all portable equipment (ventilators, IV poles, monitors, oxygen tanks) to ensure they are strictly MR Safe or MR Conditional, non-ferrous, and properly secured or tethered before entering Zone IV.

What key preparation steps must MR Personnel complete with the patient inside Zone IV prior to starting the scan?

1. Explain scan expectations (breath-holds, limiting motion, reporting heating/pain). 2. Provide fitted hearing protection. 3. Position patient and securely plug in RF coils. 4. Implement RF burn prevention padding. 5. Test two-way communication and squeeze ball. 6. Confirm protocol, operating mode, and scan duration.

What is the requirement for hearing protection during an MRI examination?

Hearing protection (earplugs and/or headphones) MUST be provided to all patients, research subjects, and companions staying in Zone IV during the scan, and proper fit and function must be verified.

How does proper patient padding prevent RF burn injuries inside the bore?

Non-conductive insulation padding ($1$-$2\text{ cm}$ thick) prevents patient skin from directly touching the bore walls, transmit coils, or conductive cables where strong capacitive RF coupling occurs.

Why must skin-to-skin contact points (e.g., crossed legs or touching thighs) be prevented during MRI?

Skin-to-skin contact forms closed conductive tissue loops. Rapidly changing RF fields ($B_1$) induce currents across these loops, leading to severe focal thermal burns at contact points.

What are the rules for managing electronic cables and lead wires inside Zone IV?

1. Route cables straight out of the bore along the center axis. 2. Never cross or loop cables. 3. Never allow cables to touch the patient's bare skin or the bore wall directly. 4. Use thermal insulation padding around cables.

What communication devices must be provided to the patient prior to initiating the scan?

• An emergency technologist notification squeeze ball (tested before starting). • A functioning two-way audio intercom system.

When should a patient be instructed to use the emergency squeeze ball?

The patient should squeeze the ball immediately if they experience localized heating, burning sensation, severe pain, unexpected loud noise, claustrophobia, or feel unwell.

What three verifications should be completed after obtaining initial localizer images?

1. Check patient comfort, safety, and willingness to proceed. 2. Inspect localizer images for concerning susceptibility artifacts indicative of hidden metal. 3. Re-confirm adequate hearing protection positioning.

Who is authorized to remove a patient or research subject from Zone IV upon exam completion?

Removal must be performed directly by Level 2 MR Personnel or under direct supervision of Level 2 MR Personnel.

What is the primary cause of MR safety accidents according to root cause analyses?

Accidents rarely result from equipment malfunction. They are typically caused by human error, non-adherence to safety SOPs, or unrecognized policy gaps.

What is the most frequently reported injury in MR imaging?

MRI-associated thermal burns.

What annual training requirement applies to Level 1 and Level 2 MR Personnel?

All Level 1 and Level 2 MR Personnel must complete annual MR safety training approved by the facility's MRMD.

In a research facility, who holds responsibility equivalent to the MRMD?

The MR Research Director (MRRD).

Within what timeframe should MR safety adverse events or 'near misses' be reported to the MRMD?

In a timely manner, typically within 24 hours or 1 business day of the occurrence.

What federal program collects medical device adverse event reports?

The FDA MedWatch program (MAUDE database).

How should a patient with an MR Conditional active implant (e.g., pacemaker or neurostimulator) be verified prior to scanning?

1. Identify model and serial numbers. 2. Consult exact manufacturer Instructions for Use (IFU) for MR conditions. 3. Confirm static field strength, spatial field gradient, $B_1+RMS$ or SAR, and lead placement rules. 4. Program device to MR Conditional mode prior to entry into Zone IV.

What protocol must be followed if an unscreened metal implant or foreign body is unexpectedly discovered while a patient is inside the scanner bore?

1. Stop imaging immediately. 2. Keep the patient stationary and move the table out slowly to minimize rotational magnetic torque ($B_0$ gradient forces). 3. Keep the patient recumbent until well away from the bore. 4. Escort patient to Zone III for urgent evaluation.