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American College of Radiology White Paper on MR Safety

he following is a report of theAmerican College of RadiologyBlue Ribbon Panel on MR Safety,

chaired by Emanuel Kanal, MD, FACR, to theTask Force on Patient Safety, chaired by JamesP. Borgstede, MD, FACR. Under the auspicesof the Task Force, the panel met in November2001 consisting of the following members: A.James Barkovich, MD; Charlotte Bell, MD,(Anesthesia Patient Safety Foundation); JamesP. Borgstede, MD, FACR; William G. Bradley,MD, PhD, FACR; Joel Felmlee, PhD; Jerry W.Froelich, MD; Ellisa M. Kaminski, RTR, MR;Emanuel Kanal, MD, FACR; Elaine K. Keeler,PhD, (NEMA); James W. Lester, MD; Eliza-beth Scoumis, RN, BSN; Loren A. Zaremba,PhD (FDA); and Marie D. Zinninger (Ameri-can College of Radiology Staff). The follow-ing document is intended to be used as atemplate for MR facilities to follow in the de-velopment of an MR safety program.

Recent articles in the medical literature andelectronic/print media [1, 2] detailing MagneticResonance Imaging (MRI) adverse incidentsinvolving patients, equipment, and personnelspotlighted the need for review. The Panel wascharged with reviewing MR safety practicesand guidelines and issuing new ones as appro-priate for MR examinations and practices today[3–7]. The document restates existing practicesand articulates new ones. This document willcontinue to evolve, as does the MRI field.

There are potential risks in the MR environ-ment, not only for the patient but also for theaccompanying family members, attendinghealth care professionals, and others who findthemselves only occasionally or rarely in themagnetic fields of MR scanners, such as secu-rity or housekeeping personnel, firefighters, po-lice, etc. These MR Safe Practices Guidelineshave been developed to help guide MR practi-tioners regarding these issues and provide a ba-sis for them to develop and implement theirown MR policies and practices. It is intendedthat these MR Safe Practice Guidelines (and thepolicies and procedures to which they give rise)be reviewed and updated on a regular basis.

It is the intent of the American College ofRadiology (ACR) that these MR Safe PracticeGuidelines will be helpful as the field of MR

evolves and matures, providing patient MRservices that are among the most powerful, yetsafest, of all diagnostic procedures to be devel-oped in the history of modern medicine.

ACR Magnetic Resonance Safe Practice Guidelines

A. Establish, Implement, And Maintain Current MR Safety Policies And Procedures

1. All clinical and research magnetic reso-nance imaging sites should maintain MRSafety Policies and Procedures, which areto be established, implemented, main-tained, and routinely reviewed and updated,as appropriate. The level of compliance bystaff will be assessed and documented an-nually. The policies and procedures manualshould be readily available to the MR pro-fessionals on site at all times of operation.

2. These policies and procedures should also bereviewed concomitant with the introductionof any significant changes in safety parame-ters in the MR imaging environment of thesite’s MR service (e.g., adding faster/strongergradient capabilities, higher RF duty cyclestudies, etc.) and updated as needed. In thisreview process, national and internationalstandards and recommendations should betaken into consideration prior to establishinglocal guidelines, policies, and procedures.

3. Each site will name an MR Medical Direc-tor whose responsibilities will include ensur-ing that these MR Safe Practice Guidelinesare established and maintained as currentand appropriate for the site. It is the responsi-bility of the site’s administration to ensurethat the policies and procedures that resultfrom these MR Safe Practice Guidelines areimplemented and adhered to at all times byall of the site’s personnel.

4. Procedures should be in place to ensurethat any and all adverse events, MR safetyincidents, or “near incidents” that occur inthe MR site are to be reported to the Med-ical Director of the MR site in a timelyfashion (e.g., within 24 hours/one busi-ness day of their occurrence) and used incontinuous quality improvement efforts.

Emanuel Kanal

1

James P. Borgstede

2

A. James Barkovich

3

Charlotte Bell

4

William G. Bradley

5

Joel P. Felmlee

6

Jerry W. Froelich

7

Ellisa M. Kaminski

1

Elaine K. Keeler

8

James W. Lester

9

Elizabeth A. Scoumis

1

Loren A. Zaremba

10

Marie D. Zinninger

11

Received January 8, 2002; accepted after revision March 5, 2002.

1

Department of Radiology, Magnetic Resonance Services, University of Pittsburgh Medical Center 200 Lothrop St., Pittsburgh, PA 15213-2582.

2

Penrose St. Francis Health System, Colorado Springs, CO 80907.

3

Department of Neuroradiology, Rm. L 371, University of California at San Francisco, 505 Parnassus Ave., San Francisco, CA 94143-0628.

4

Department of Anesthesiology, Yale University School of Medicine, 333 Cedar St., P. O. Box 208051, New Haven, CT 06520-8051.

5

Department of Radiology, Long Beach Memorial Medical Center, University of California, Irvine, 403 E. Columbia St., Long Beach, CA 90806.

6

Department of Radiology, Mayo Clinic, 200 1st St. S.W., Rochester, MN 55902-3008.

7

Department of Radiology, Hennepin County Medical Center and The University of Minnesota, 701 Park Ave., Minneapolis, MN 55415.

8

National Electrical Manufacturers Association, Philips Medical Systems, 595 Miner Rd., Cleveland, OH 44143.

9

Durham Radiology Associates, Ste. 500, 4323 Ben Franklin Blvd., Durham, NC 27704.

10

Office of Device Evaluation, Center for Devices and Radiological Health, U.S. Food and Drug Administration, 9200 Corporate Blvd., HFZ-470, Rockville, MD 20850.

11

American College of Radiology, 1891 Preston White Dr., Reston, VA 20191. Address correspondence to M. D. Zinninger.

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B. STATIC MAGNETIC FIELD ISSUES: SITE ACCESS RESTRICTION

1. Zoning:The MR site is conceptually divided into fourZones (Fig. 1) as follows.a. Zone I: This includes all areas that are

freely accessible to the general public.This area is typically outside of the MRenvironment itself and is the areathrough which patients, health care per-sonnel, and other employees of the MRsite access the MR environment.

b. Zone II: This area is the interface be-tween the publicly accessible uncon-trolled Zone I and the strictly controlledZone III and IV (see below). Typicallypatients are greeted in Zone II and arenot free to move throughout Zone II atwill, but are rather under the supervi-sion of MR Personnel (see Section 2b,below). It is in Zone II that the answersto MR screening questions, patient his-tories, medical insurance questions,etc., are typically obtained.

c. Zone III: This area is the region in whichfree access by unscreened non–MR Per-sonnel and/or ferromagnetic objects andequipment can result in serious injury or

death as a result of interactions betweenthe individuals/equipment and the MRscanner’s particular environment. Theseinteractions include but are not limited tothose involving the MR scanner’s staticand time varying magnetic fields. All ac-cess to Zone III is to be strictly restricted,with access to regions within it (includingZone IV, see below) controlled by, andentirely under the supervision of, MRPersonnel (see Section 2b, below). Spe-cifically identified MR Personnel (typi-cally—but not necessarily only—the MRTechnologists) are to be charged with en-suring that this MR Safe Practice Guide-line is strictly adhered to for the safety ofthe patients and other non–MR person-nel, the health care personnel, and theequipment itself. This function of the MRPersonnel is directly under the authorityand responsibility of the MR Medical Di-rector or the Level Two–designated (seesection 2b, below) physician of the dayfor the MR site.

Zone III regions should be physicallyrestricted from general public access—forexample, by key locks, pass-key lockingsystems, or any other reliable physically

restricting method that can differentiatebetween MR Personnel and non–MRPersonnel. The use of combination locksis to be discouraged as combinations of-ten tend to become more widely distrib-uted than initially intended, resulting insite restriction violations being morelikely with these devices. Only MR Per-sonnel shall be provided with free ac-cess, such as the access keys/passkeys,to Zone III regions.

There should be NO exceptions tothis guideline. Specifically, this includeshospital/site administration, physician, se-curity, and other non–MR Personnel (seesection 2b, below). Non–MR personnel arenot to be provided with independent ZoneIII access until such time as they undergothe proper education and training and be-come MR Personnel themselves. ZoneIII regions or at the very least the areawithin them wherein the static magneticfield’s strength exceeds 5-gauss shouldbe clearly marked and demarcated as be-ing potentially hazardous.

d. Zone IV: This area is synonymous with theMR scanner magnet room itself—i.e., thephysical confines of the room within whichthe MR scanner itself is located. Zone IV,by definition, will always be located withinZone III as it is the MR magnet and its as-sociated magnetic field that generates theexistence of Zone III itself. Zone IV re-gions should also be clearly marked anddemarcated as being potentially hazardousdue to the presence of very strong magneticfields. As part of the Zone IV site restric-tion, all MR installations should be in-stalled in such a way as to provide for directvisual observation by Level II MR Person-nel to access pathways into Zone IV re-gions. By means of illustration only, theMR Technologists would be able to di-rectly observe and control, via line of site orvia video monitors, the entrances or accesscorridors to Zone IV regions from theirnormal positions when stationed at theirdesks in the scan control room.

Zone IV/MR magnet rooms shouldbe clearly marked with a lighted sign andred light stating, “The Magnet is On.”Except for resistive systems, this sign/redlight should be illuminated at all timesand should be provided with a backupenergy source to continue to remain illu-minated for at least 24 hours in the eventof a loss of power to the site.

In case of cardiac or respiratory arrestor other medical emergency within ZoneFig. 1.—MR site floor plan.

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IV for which emergent medical interven-tion and/or resuscitation is required, ap-propriately trained and certified MRPersonnel should immediately initiatebasic life support and/or CPR as requiredby the situation WHILE the patient is be-ing emergently removed from the MRmagnet room/Zone IV to a predeter-mined magnetically safe location. ALLPRIORITIES SHOULD BE FOCUSEDON STABILIZING (E.G., BASIC LIFESUPPORT WITH CARDIAC COM-PRESSIONS AND MANUAL VENTI-LATION) AND THEN EVACUATINGTHE PATIENT AS RAPIDLY ANDSAFELY AS POSSIBLE FROM THEMAGNETIC ENVIRONMENT THATMIGHT RESTRICT SAFE RESUSCI-TATIVE EFFORTS.

Further, for logistical safety reasons,the patient should always be removedfrom ZONE IV (the magnet room it-self) to the prospectively identified lo-cation where full resuscitative effortsare to continue.

Quenching the magnet (for supercon-ducting systems only) is not routinely ad-vised for cardiac or respiratory arrest orother medical emergency, since quench-ing the magnet itself and having the mag-netic field dissipate could easily takemore than a minute. Furthermore, asquenching a magnet can theoretically behazardous, ideally one should evacuatethe magnet room, when possible, for anintentional quench. One should rather usethat time wisely to initiate life supportmeasures while removing the patientfrom Zone IV/the MR magnet room to alocation where the strength of the mag-netic field(s) is insufficient to be a medicalconcern. ZONE III AND ZONE IV SITEACCESS RESTRICTION MUST BEMAINTAINED DURING RESUSCITA-TIONS AND/OR OTHER EMERGENTSITUATIONS FOR THE PROTECTIONOF ALL INVOLVED.

2. MR Personnel/Non–MR Personnel a. All individuals working within at least

Zone III of the MR environment shouldbe documented to have completed suc-cessfully at least one of the MR site’s ap-proved MR safety live lectures orprerecorded presentations as approvedby the MR Medical Director. Attendanceshould be repeated at least annually, andappropriate documentation should beprovided. These individuals shall be re-ferred to henceforth as MR Personnel.

b. There are two levels of MR Personnel.1. Level One MR Personnel: Those who

have passed minimal safety educa-tional efforts to ensure their ownsafety as they work within Zone III re-gions will be referred to henceforth asLevel One MR Personnel.

2. Level Two MR Personnel: Those whohave been more extensively trainedand intensively educated in thebroader aspects of MR safety issuesincluding, for example, issues relatedto the potential for thermal loading/burns, direct neuromuscular excitationfrom rapidly changing gradients, etc.,shall be referred to henceforth asLevel Two MR Personnel. It is the re-sponsibility of the MR Medical Direc-tor of the site not only to identify thenecessary training, but also to identifythose individuals that qualify as LevelTwo MR Personnel. It is understoodthat the Medical Director of the MRsite will be one whose education andexperience in MR safety qualifiesthem for designation as Level TwoMR Personnel.

c. All those not having successfully com-plied with these MR safety instructionguidelines shall be referred to henceforthas Non–MR Personnel.

3. Patient/Non–MR Personnel Screeninga. ALL Non–MR Personnel wishing to en-

ter Zone III regions of the MR Site musthave first successfully passed an MRsafety screening process to be performedby authorized MR Personnel. Only MRPersonnel are authorized to perform anMR safety screen prior to permittingNon–MR Personnel into Zone III areas.

b. Metal DetectorsThe usage of metal detectors in MR en-vironments is NOT recommended.Reasons for this recommendation in-clude, among others: 1. They have varied—and variable—

sensitivity settings. 2. The skills of the operators can vary. 3. Today’s metal detectors cannot de-

tect, for example, a 2

×

3 mm, po-tentially dangerous ferromagneticmetal fragment in the orbit, near thespinal cord, or heart, etc.

4. Today’s metal detectors do not dif-ferentiate between ferromagneticand nonferromagnetic metallic ob-jects/implants/foreign bodies.

5. Metal detectors should not be neces-sary for the detection of large metallic

objects such as oxygen tanks on thegurney with the patients. These objectsare fully expected to be detected—andphysically excluded—during the rou-tine patient screening process.

c. Non–MR Personnel should be accom-panied by, or under the immediate su-pervision and visual/verbal contactwith, one specifically identified LevelTwo MR Person for the entirety of theduration during which the Non–MRPersonnel remain within Zone III orZone IV restricted regions. However, itis acceptable to have them in a chang-ing room or restroom not in visual con-tact in Zone III as long as personneland the patient can verbally communi-cate with each other.

In the event of a shift change, lunchbreak, etc., no Level Two MR Personnelshall relinquish their responsibility to su-pervise the Non–MR Personnel stillwithin Zone III or Zone IV under theircharge until such supervision has beenformally transferred to another of theLevel Two MR Personnel of the MR Site.

d. Non-emergent patients should be MRsafety screened onsite by a minimum oftwo separate individuals. At least one ofthese individuals should be one of theLevel Two MR Personnel of the MR site.At least one of these two screens shouldbe performed verbally/interactively.

Emergent patients and their accom-panying Non–MR Personnel may bescreened only once providing that thescreening individual is one of the site’sLevel Two MR Personnel.

There should be no exceptions to this.e. Any individual undergoing an MR pro-

cedure must remove all readily remov-able metallic personal belongings anddevices on or in them (e.g., watches;jewelry; pagers; cell phones; body pierc-ings, if removable; contraceptive dia-phragms; metallic drug delivery patches;and clothing items that may contain me-tallic fasteners, hooks, zippers, loose me-tallic components, or metallic threads;cosmetics containing metallic particles,such as eye makeup). It is therefore ad-visable to require that the patients or re-search subjects wear a site-suppliedgown with no metal fasteners during theMR procedure when feasible.

f. All patients/Non–MR Personnel with ahistory of a potential ferromagnetic for-eign object penetration must undergofurther investigation prior to being per-

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mitted entrance to Zone III of the MRsite. Examples of acceptable methodsof screening include patient history,plain x-ray films, prior CT or MR ofthe questioned anatomic area, or accessto written documentation as to the typeof implant or foreign object that mightbe present. Once positive identificationhas been made as to the type of im-plant/foreign object that is within a pa-tient, best effort assessments should bemade to attempt to identify the MRcompatibility or MR safety of the im-plant/object. Efforts at identificationmight include written testing on the im-plant prior to implantation (preferred),product labeling regarding the implant/object, peer-reviewed publications re-garding MR compatibility, and MRsafety testing of the make/model/typeof the object, etc. MR safety testingwould only be of value assuming thatthe object/device has not been alteredsince such testing had been published.

All patients who have a history oforbit trauma by a potential ferromag-netic foreign body

for which theysought medical attention

are to havetheir orbits cleared by either plain x-rayorbit films (two views) [8, 9] or by a ra-diologist’s review and assessment ofcontiguous cut prior CT or MR images(obtained since the suspected traumaticevent) if available.

g. Conscious, non-emergent patients and re-search and volunteer subjects are to com-plete written MR safety screeningquestionnaires prior to their introductioninto Zone III regions. Family/guardians ofnon-responsive patients or of patients whocannot reliably provide their own medicalhistories are to complete a written MRsafety screening questionnaire prior totheir introduction into Zone III regions.These completed questionnaires are thento be reviewed orally with the patient/guardian/research subject in their entiretyprior to permitting the patient/researchsubject to be cleared into Zone III regions.

The patient/guardian/research subjectas well as the screening MR staff mem-ber must both sign the completed form.This should then become a part of thepatient’s medical record. No empty re-sponses will be accepted—each questionMUST be answered definitively with a“Yes” or “No” or provide specific furtherinformation as requested. A sample of apre–MR screening form is provided

(Appendixes 2–5). This is the minimuminformation to be obtained; more may beadded if the site so desires.

h. Screening of the patient/Non–MR Per-sonnel with, or suspected of having, anintracranial aneurysm clip should beperformed as per the separate MR SafePractice Guideline addressing this par-ticular topic (see section K, below).

i. Screening of all unconscious/unresponsivepatients and/or patients who cannot pro-vide their own reliable histories, or whenthe history cannot be reliably obtainedfrom others, regarding prior possible ex-posures to surgery, trauma, and/or metal-lic foreign object history/exposure, inwhom an MR examination is deemedclinically indicated/necessary: 1. If no reliable patient metal exposure

history can be otherwise obtained andif the requested MR examination can-not reasonably wait until such a timethat a reliable such history might beobtained, it is recommended that suchpatients be physically examined byLevel Two MR Personnel. All areas ofscars or deformities that might be ana-tomically indicative of an implant suchas on the chest or spine region, etc.,and whose origins are unknown andwhich may have been caused by ferro-magnetic foreign bodies, implants,etc., should be subject to plain film ra-diography (if such recently obtainedplain films or computer tomographicor magnetic resonance studies of suchareas are not already available). Theinvestigation described above shouldbe made to ensure that there are no po-tentially harmful embedded/im-planted metallic foreign objects ordevices. All such patients should alsoundergo plain film imaging of theskull/orbits and chest to exclude metal-lic foreign objects (if recently obtainedsuch radiographic and/or MR informa-tion is not already available).

2. Monitoring of patients is sometimesnecessary in the MR scanner. The po-tential for thermal injury from possiblyexcessive radiofrequency power depo-sition exists. Sedated, anesthetized,and/or unconscious patients may notbe able to express symptoms of suchinjury. This potential for injury isgreater on especially higher fieldwhole-body scanners (e.g., 1 Tesla andabove). Much patient monitoring infor-mation can be satisfactorily acquired

via pulse oximetry and/or other meanswithout utilization of electrocardio-graphic tracing and its inherent thermalinjury risks. Patients who require EKGmonitoring and who are, unconscious,sedated, and/or anesthetized should beexamined with potential repositioning,after each imaging sequence, of theEKG leads and any other electricallyconductive material with which the pa-tient is in contact. Alternatively, coldcompresses or ice packs could beplaced upon all necessary electricallyconductive material that touches thepatient during scanning.

j. Final determination of whether or not toscan any given patient with any givenimplant, foreign body, etc., is to be madeby the Level Two designated attendingMR radiologist, or the MR Medical Di-rector, or specifically designated LevelTwo MR Personnel following criteria foracceptability for MR scanning predeter-mined by the Medical Director.

k. All Non–MR Personnel (e.g., patients,volunteers, varied site employees and pro-fessionals, etc.) with implanted cardiacpacemakers, autodefibrillators, diaphrag-matic pacemakers, and/or other electrome-chanically activated devices on whosefunction the Non–MR Personnel is depen-dent should be precluded from the MRmagnet room/Zone IV and physically re-strained from the 5-gauss line unless spe-cifically cleared in writing by a Level TwoMR Personnel–designated radiologist at-tending physician or the Medical Directorof the MR site. In such circumstances, spe-cific defending risk/benefit rationaleshould be provided in writing and signedby the authorizing radiologist.

Should it be determined that Non–MRPersonnel wishing to accompany a patientinto an MR scan room require their orbitsto be cleared by plain film radiography, aradiologist must first discuss with theNon–MR Personnel that plain x-ray filmsof their orbits are required prior to permit-ting them access to the MR scan room.Should they still wish to proceed with ac-cess to Zone IV and/or within the 5-gaussline, and should the attending radiologistdeem it medically advisable that they doso (e.g., for the care of their child about toundergo an MR study), written informedconsent should be provided by these ac-companying Non–MR Personnel prior totheir undergoing x-ray examination oftheir orbits.


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l. MR scanning of patients/prisoners/parolees with metallic prisoner re-straining devices or radiofrequencyID/tracking bracelets could lead totheoretical potential adverse eventsincluding: 1) ferromagnetic attractiveeffects and resultant patient injury, 2)possible ferromagnetic attractive ef-fects and potential damage to the de-vice and/or its battery pack, 3)radiofrequency (RF) interferencewith the MR imaging study and sec-ondary image artifact, 4) RF interfer-ence with the functionality of thedevice, 5) RF power deposition andheating of the bracelet tagging deviceor its circuitry and secondary patientinjury (if the bracelet would be in theanatomic volume of the RF transmit-ter coil being imaged). Therefore, incases where requested to scan a pa-tient/prisoner/parolee wearing radio-frequency tagging bracelets and/ormetallic handcuffs or anklecuffs, re-quest that the patient be accompaniedby the appropriate authorities whocan and will remove the restrainingdevice prior to the MR study and becharged with its replacement follow-ing the examination.

m. Firefighter/Police/Security safety con-siderations: For the safety of firefight-ers and other emergent servicesresponding to an emergent call at theMR site, it is recommended that allfire alarms, cardiac arrests, or otheremergent service response calls origi-nating/located in the MR site shouldbe forwarded simultaneously to a spe-cifically designated individual fromamongst the site’s MR Personnel. Thisindividual should, if possible, be on-site prior to the arrival of the firefight-ers/emergent responders to ensure thatthey do not have free access to ZoneIII or Zone IV. The site might considerassigning appropriately trained secu-rity personnel, who have been trainedand designated as MR Personnel, torespond to such calls.

In any case, all MR sites should ar-range to prospectively educate their localfire marshals/firefighters associationsand police/security personnel about thepotential hazards of responding to emer-gencies in the MR suite.

It should be stressed that even inthe presence of a true fire (or otheremergency) in Zone III and/or Zone

IV, the magnetic fields may bepresent and fully operational. There-fore, free access to Zone III or ZoneIV by firefighters and/or other Non–MR Personnel with air tanks, axes,crowbars, other firefighting equip-ment, guns, etc., might prove cata-strophic or even lethal to thoseresponding or others in the vicinity.

As part of the Zone III/IV re-strictions, all MR sites must haveclearly marked MR-compatible fireextinguishing equipment physicallystored within and readily accessibleto Zone III/IV regions. All Non–MRcompatible fire extinguishers andother firefighting equipment shouldbe restricted from being broughtinto Zone III regions.

For superconducting magnets, thehelium (and the nitrogen as well, inthe older magnets) is not flammableand does not pose a fire hazard di-rectly. However, the liquid oxygenthat can result from the supercooledair in the vicinity of the releasedgases might well increase the firehazard in this area. If there are appro-priately trained and knowledgeableMR personnel available during theemergency to ensure that emergencyresponse personnel responding to thefire call are kept out of the MR scan-ner/magnet room and 5-gauss line,then quenching the magnet during re-sponse to an emergency or fire shouldnot be a requirement.

HOWEVER, if the fire is in such alocation where Zone III/IV needs to beentered for whatever reason by thefirefighting and/or emergency re-sponse personnel and their firefightingand emergent equipment such as aircanisters, crowbars, axes, defibrilla-tors, etc., a decision to quench a super-conducting magnet at that point shouldbe VERY seriously considered to pro-tect the health and lives of the emer-gent responding personnel in such anemergency situation. Should a quenchbe performed, appropriately desig-nated MR personnel still need to en-sure that ALL non–MR personnel(including and especially emergentlyresponding personnel) continue to berestricted from Zone III/IV regions un-til the designated MR Personnel havepersonally verified that the static fieldis either no longer detectable or at least

sufficiently attenuated so as to nolonger present a potential hazard toone moving by it with, for example,large ferromagnetic objects such asoxygen tanks, axes, etc.

For resistive systems, the magneticfield of the MR scanner should beshut down as completely as possibleand verified as such prior to permit-ting the emergency response person-nel access to the magnet/Zone IV. Forpermanent or resistive or hybrid sys-tems whose magnetic fields cannot becompletely shut down, MR personnelshould be available to warn the emer-gency response personnel that a verypowerful magnetic field is still opera-tional in the magnet room/Zone IV.

4. MR Personnel ScreeningAll MR Personnel are to undergo an MRscreening process as part of their employmentinterview process to ensure their own safety inthe MR environment. For their own protec-tion and for the protection of the Non–MR Per-sonnel under their supervision, all MRPersonnel must immediately report to the MRMedical Director any trauma, procedure, orsurgery that they experience or undergo inwhich a ferromagnetic metallic object/devicemay have become introduced within or onthem. This will permit an appropriate screen-ing to be performed upon the employee to de-termine the safety of permitting that MRPersonnel–designated employee into theZone III environment of the MR site.

5. Device/Object ScreeningAs part of the Zone III site restriction andequipment testing/clearing responsibili-ties, all sites should have ready access to astrong handheld magnet (

≥

1000-gauss).This will enable the site to test externaland even some superficial internal devicesor implants for the presence of grossly de-tectable ferromagnetic attractive forces. a. All portable metallic or partially metallic

devices that are on or external to the pa-tient (e.g., oxygen cylinders) are to bepositively identified in writing as non-fer-romagnetic and either MR safe or MRcompatible prior to permitting them intoZone III regions. For all device/objectscreening, all verification and positiveidentification should be in writing. Exam-ples of such devices that need to be posi-tively identified include fire extinguishers,oxygen tanks, aneurysm clips, etc.

b. If external devices/objects are demon-strated to be ferromagnetic and Non–MR safe/MR compatible, they may

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still, under specific circumstances, bebrought into Zone III regions if, for ex-ample, they are deemed by MR Person-nel to be necessary and appropriate forthe care of the patient. They shouldonly be brought into Zone III regions ifthey are under the direct supervision ofspecifically designated either LevelOne or Level Two MR Personnel whoare thoroughly familiar with the device,its function, and the reason supportingits introduction into the Zone III desig-nated region. The safe utilization ofthese devices at all times while they arepresent in Zone III will be the responsi-bility of a specifically named LevelOne or Two MR Personnel. This devicemust be appropriately physically se-cured or restricted at all times duringwhich it is in Zone III regions to ensurethat it does not inadvertently becomeintroduced too close to the MR scannerand accidentally become exposed tostatic magnetic fields/gradients thatmight result in its becoming either ahazardous projectile or no longer accu-rately functional.

c. Never assume MR compatibility orsafety information about the device if itis not clearly documented in writing.All unknown external objects/devicesbeing considered for introduction be-yond Zone II regions should be testedwith a strong handheld magnet (

≥

1000-gauss) for ferromagnetic propertiesprior to permitting them entry beyondZone II regions. The results of suchtesting as well as the date, time, andname of tester, and methodology usedfor that particular device should bedocumented in writing. If a device hasnot been tested and/or its MR compati-bility/safety status is unknown, itshould NOT be permitted unrestrictedaccess beyond Zone II regions.

d. All portable metallic or partially metallicobjects that are to be brought into ZoneIV regions (i.e., the MR magnet room it-self) must be labeled with either a green“MR Safe” label or a red “Not MR Safe”label. As noted in section 5 introductionabove, testing for the purpose of this la-beling is to be accomplished by the site’sMR personnel by exposing the metallicobject to a handheld magnet (

≥

1000-gauss). If grossly detectable attractiveforces are observed between the metallicobject or any of its components and thehandheld magnet, it is to be labeled with

a red label. If no such forces are ob-served, a green label is to be affixed tothe device/object prior to its introductioninto Zone IV.

e. Decisions based on published MRcompatibility or safety claims shouldrecognize that all such claims apply tospecifically tested static field and staticgradient field strengths. For example,“MR compatible up to 3.0 Tesla at gra-dient strengths of 400-gauss/cm,” or“MR safe tested up to 1.5 Tesla up tomaximum static gradient fields experi-enced in an unshielded 1.5 Tesla [man-ufacturer name] whole body MRscanner tested 1.5 feet within the bore.”

f. It should be noted that alterations per-formed by the site on MR safe/compat-ible equipment or devices may alter theMR safety and/or compatibility proper-ties of the device. For example, tying aferromagnetic metallic twisting binderonto a sign labeling the device as MRcompatible might result in artifact in-duction—or worse—if introduced intothe MR scanner in that altered manner.

C. MR SAFE PRACTICE GUIDELINES: MR TECHNOLOGIST

1. MR Technologists should be ARRT Reg-istered Technologists (RT). Furthermore,all MR Technologists must be trained asLevel Two MR Personnel during theirorientation, prior to being permitted freeaccess to Zone III.

2. All MR Technologists will maintain cur-rent certification in American Heart Asso-ciation Basic Life Support at the HealthCare Provider level.

3. Except for emergent coverage, there willbe a minimum of two MR technologistsor one MR Technologist and one other in-dividual with the designation of MR Per-sonnel in the immediate Zone II throughZone IV MR environment. For emergentcoverage, the MR Technologist can scanwith no other individuals in their Zone IIthrough Zone IV MR environment aslong as there is in-house ready emergentcoverage by designated Department ofRadiology MR Personnel (e.g., radiologyhouse staff, radiology attendings, etc.).

D. PREGNANCY-RELATED ISSUES

1. Health care practitioner pregnanciesPregnant health care practitioners are per-mitted to work in and around the MR envi-ronment throughout all stages of theirpregnancy [10]. This includes but is not

limited to positioning patients, scanning,archiving, injecting contrast, entering theMR scan room in response to an emer-gency, etc. Although permitted to work inand around the MR environment, pregnanthealth care practitioners are requested notto remain within the MR scanner bore orZone IV during actual data acquisition/scanning itself.

2. Patient pregnancies a. Pregnant patients can be accepted to un-

dergo MR scans at any stage of preg-nancy if, in the determination of a LevelTwo MR Personnel–designated attend-ing radiologist, the risk–benefit ratio tothe patient warrants that the study beperformed. The radiologist should con-fer with the referring physician and doc-ument this in the radiology report or thepatient’s medical record that:1. The information requested from the

MR study cannot be acquired vianon-ionizing means (e.g., ultra-sonography), and

2. The data is needed to potentiallyaffect the care of that patient and/orfetus DURING the pregnancy, and

3. The referring physician does notfeel that it is prudent to wait to ob-tain this data until after the patientis no longer pregnant.

b. MR contrast agent(s) should NOT beroutinely provided to pregnant patients.This, too, is a decision that must bemade on a case-by-case basis by thecovering Level Two MR Personnel–designated attending radiologist whowill assess the risk–benefit ratio forthat particular patient.

c. It is recommended that pregnant pa-tients undergoing an MR examinationprovide written informed consent todocument that they understand therisks/benefits of the MR procedure tobe performed, the alternative diagnos-tic options available to them (if any),and that they wish to proceed.

E. TIME VARYING GRADIENT MAGNETIC FIELD–RELATED ISSUES: INDUCED VOLTAGES

Types of patients needing extra caution:Patients with implanted or retained wires inanatomically and/or functionally sensitiveareas (e.g., myocardium or epicardium, im-planted electrodes in the brain) should beconsidered at higher risk especially fromfaster MR imaging sequences, such asechoplanar imaging (which may be used insuch sequences as diffusion weighted imag-


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ing, functional imaging, perfusion weightedimaging, MR angiographic imaging, etc.).The decision to limit the dB/dt (rate of mag-netic field change) and maximum strength ofthe magnetic field of the gradient subsystemsduring imaging of such patients should be re-viewed by the Level Two MR Personnel–designated attending radiologist supervisingthe case/patient.

F. TIME VARYING GRADIENT MAGNETIC FIELD–RELATED ISSUES: AUDITORY CONSIDERATIONS

1. All patients/volunteers should be offeredand encouraged to use hearing protectionprior to their undergoing any imaging inthe MR scanners.

2. All patients/volunteers in whom researchsequences are to be performed (i.e., MRscan sequences that have not yet been ap-proved by the Food and Drug Administra-tion [FDA]) are to have hearing protectivedevices IN PLACE prior to initiating anysuch research MR sequences on these pa-tient/volunteers. Without hearing protec-tion in place, MR imaging sequences thatare not FDA approved should not be per-formed on patients/volunteers.

G. TIME VARYING RADIOFREQUENCY MAGNETIC FIELD–RELATED ISSUES: THERMAL

1. All unnecessary and/or unused electricallyconductive materials should be removedfrom the MR system before the onset of im-aging. It is not sufficient to merely “un-plug” or disconnect unused unnecessaryelectrically conductive material and leave itwithin the MR scanner with the patient dur-ing imaging. All electrical connections suchas on surface coil leads, monitoring de-vices, etc., must be visually checked by thescanning MR Technologist prior to eachscan to ensure the integrity of the thermaland electrical insulation.

2. For electrically conductive material, wires,leads, implants, etc., that are required to re-main within the bore of the MR scanner withthe patient during imaging, care should betaken to ensure that no large caliber electri-cally conducting loops (including patient tis-sue; see section g, 5, below) are permitted tobe formed within the MR scanner.

3. For electrically conductive material, wires,leads, implants, etc., that are required to bewithin the bore of the MR scanner with thepatient during imaging, care should betaken to place thermal insulation (includingair, pads, etc.) between the patient and theelectrically conductive material during im-aging, while simultaneously attempting to

(as much as feasible) keep the electricalconductor from directly contacting the pa-tient during imaging. It is also appropriateto try to position the leads/wires as far aspossible from the inner walls of the MRscanner if the body coil is being used for ra-diofrequency transmission. When it is nec-essary that such electrically conductiveleads directly contact the patient during im-aging, consideration should be given toprophylactic application of cold com-presses or ice packs to such areas.

4. Depending on specific magnet designs,care may be needed to ensure that the pa-tient’s tissue(s) do not directly come intocontact with the inner bore of the MR im-ager during the MR imaging process. Thiscare is especially important for severalhigher field MR scanners. The manufactur-ers of these devices provide pads and othersuch insulating devices for this purpose,and manufacturer guidelines should bestrictly adhered to for these units.

5. It is also important to ensure that the pa-tient’s own tissues do not form large con-ductive loops. Therefore, care should betaken to ensure that the patient’s arms/legs not be positioned in such a way as toform a large-caliber loop within the boreof the MR imager during the imaging pro-cess. For this reason, it is preferable thatpatients be instructed not to cross theirarms or legs in the MR scanner.

6. Skin Staples/Superficial Metallic Sutures:Patients requested to undergo MR studies inwhom there are skin staples or superficialmetallic sutures (SMS) may be permitted toundergo the MR examination if the skin sta-ples/SMS are not ferromagnetic and are notin the anatomic volume of RF power deposi-tion for the study to be performed. If thenonferromagnetic skin staples/SMS arewithin the volume to be RF irradiated for therequested MR study several precautions arerecommended, as follows: a. Warn the patient and make sure that

they are especially aware of the possi-bility that they may experience warmthor even burning along the skin staple/SMS distribution. The patient shouldbe instructed to report immediately ifthey experience a warmth or burningsensations during the study (and not,for example, wait until the “end of theknocking noise”).

b. It is recommended that a cold com-press/ice pack be placed along the skinstaples/SMS if this can be safely clini-cally accomplished during the MR im-

aging examination. This will help toserve as a heat sink for any focal powerdeposition that may occur, thus de-creasing the likelihood of a clinicallysignificant thermal injury/burn to adja-cent tissue.

7. For patients with extensive and/or dark tat-toos including tattooed eyeliner, in order todecrease the potential for radiofrequencyheating of the tattooed tissue it is recom-mended that cold compresses or ice packsbe placed onto the tattooed area(s) and keptin place throughout the MR imaging pro-cess if these tattoos are within the volumein which the body coil is being used for RFtransmission. This approach is especiallyappropriate if fast spin-echo (or other highRF duty cycle) MR imaging sequences areanticipated to be used in the study. If an-other coil is being used for RF transmis-sion, a decision must be made if high RFtransmitted power is to be anticipated bythe study protocol design. If so then theabove precautions should be followed inthat case as well. Additionally, patients withtattoos that had been placed within 48 hoursprior to the pending MR examinationshould be advised of the potential forsmearing or smudging of the edges of thefreshly placed tattoo.

8. The unconscious/unresponsive patientshould have any/all attached leads coveredwith a cold compress/ice pack at the leadattachment site for the duration of the MRstudy prior to the initiation of scanning.

9. Patients in whom there are long electricallyconductive leads such as Swan-Ganz ther-modilution cardiac output capable cathe-ters, Foley catheters with electricallyconductive leads, etc., should be consideredat risk for MR studies if the body coil is tobe used for RF transmission over the regionof the electrically conductive lead. This isespecially true for higher field systems andfor imaging protocols utilizing fast spinecho or other high RF duty cycle MR imag-ing sequences. Each such patient should bereviewed and cleared by an attending LevelTwo radiologist and a risk benefit ratio as-sessment performed prior to permittingthem access to the MR scanner.

H. CRYOGEN-RELATED ISSUES

1. For superconducting systems, in the event of asystem quench it is imperative that all person-nel/patients be evacuated from the MR scanroom as quickly as safely feasible and the siteaccess be immediately restricted to all indi-viduals until the arrival of the MR equipment

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service personnel. This is especially so ifcryogenic gases are observed to have ventedpartially or completely into the scan room it-self, as evidenced in part by the sudden ap-pearance of white “clouds” or “fog” aroundor above the MR scanner. As noted in sectionB.2.m above, it is especially important to en-sure that all police/fire response personnel arerestricted from entering the MR scan roomwith their equipment (axes, air canisters,guns, etc.) until it can be confirmed that themagnetic field has been successfully dissi-pated, as there may still be considerable staticmagnetic field present despite a quench orpartial quench of the magnetic field.

2. It should be pointed out that room oxygenmonitoring was discussed by the MRBlue Ribbon Panel and rejected at thistime because the present oxygen monitor-ing technology was considered by indus-try experts to not be sufficiently reliableto allow for continued operation duringsituations of power outages, etc.

I. CLAUSTROPHOBIA/ANXIETY/SEDATION–ANALGESIA/ANESTHESIA MR SAFE PRACTICE GUIDELINES

Adult and pediatric patient anxiolysis, se-dation, analgesia, and anesthesia for any rea-son should follow established AmericanCollege of Radiology (ACR) [11, 12], Amer-ican Society of Anesthesiologists (ASA)[13–16], and JCAHO standards [17].

J. CONTRAST AGENT SAFETY MR SAFE PRACTICES

1. Contrast agent administration issuesNo patient is to be administered prescrip-tion MR contrast agents without ordersfrom a duly licensed physician. Intravenousinjection-qualified MR technologists maystart and attend to peripheral intravenousaccess/lines if they have undergone the req-uisite site-specified training in peripheral IVaccess and have demonstrated and docu-mented appropriate proficiency in this area.IV-qualified MR technologists may admin-ister FDA-approved gadolinium-based MRcontrast agents via peripheral intravenousroutes as a bolus or slow or continuous in-jection, as directed by the orders of a dulylicensed site physician. a. Administration of these agents is to be

performed as per the ACR policy(Res.1-H, 1987, 1997):

The ACR approves of the injectionof contrast material and diagnosticlevels of radiopharmaceuticals bycertified and/or licensed radio-logic technologists and radiologicnurses under the direction of a ra-

diologist or his or her physiciandesignee who is personally andimmediately available, if the prac-tice is in compliance with institu-tional and state regulations. Theremust also be prior written approvalby the medical director of the radi-ology department /service of suchindividuals; such approval processhaving followed established poli-cies and procedures, and the radio-logic technologists and nurses whohave been so approved maintaindocumentation of continuing med-ical education related to materialsinjected and to the procedures be-ing performed.

2. Prior contrast agent reaction issues [18]:a. Adverse events after intravenous injec-

tion of gadolinium seem to be morecommon in patients who had previousreactions to an MR contrast agent. Inone study, 16 (21%) of 75 patients whohad previous adverse reactions to MRcontrast agents reacted to subsequentinjections of gadolinium. Patients withasthma also seem to be more likely tohave an adverse reaction to gadolin-ium. Patients with allergies alsoseemed to be at increased risk (~2.0–3.7 times, compared with patientswithout allergies). Patients who havehad adverse reactions to iodinated con-trast media are more than twice aslikely to have an adverse reaction togadolinium (6.3% of 857 patients).

b. At present there are no well-defined poli-cies for patients who are considered to beat increased risk for having adverse reac-tion to MR contrast agents; however, thefollowing recommendations are sug-gested: patients who have previously re-acted to one MR agent can be injectedwith another agent, if they are restudied,and at-risk patients can be pre-medicatedwith corticosteroids and, occasionally,antihistamines [18].

c. All patients with asthma, allergic respi-ratory histories, prior iodinated and/orgadolinium-based contrast reactions,etc., be followed more closely as theyare at a demonstrably higher risk of ad-verse reaction.

K. MR SAFE PRACTICE GUIDELINES REGARDING MR SCANNING OF PATIENTS IN WHOM THERE ARE/MAY BE INTRACRANIAL ANEURYSM CLIPS

1. In the event that it is unclear whether a pa-tient does or does not have an aneurysm

clip in place, plain films should be obtained.Alternatively, if available, any cranial plainfilms, CT or MR examination that mayhave already been taken in the recent past(i.e., subsequent to the suspected surgicaldate) should be reviewed to assess for apossible intracranial aneurysm clip.

2. In the event that a patient is identified tohave an intracranial aneurysm clip in place,the magnetic resonance examination shouldnot be performed until it can be docu-mented that the type of aneurysm clipwithin that patient is MR safe/compatible.All documentation of types of implantedclips, dates, etc., MUST be in writing andsigned by a licensed physician. Phone orverbal histories and histories provided by anon-physician are not acceptable. Fax cop-ies of operative reports, physician state-ments, etc., are acceptable as long as alegible physician signature accompanies therequisite documentation. A written historyof the clip itself having been appropriatelytested for ferromagnetic properties (and de-scription of the testing methodology used)prior to implantation by the operating sur-geon is also considered acceptable if thetesting follows the ASTM (American Soci-ety of Testing and Materials) establishedDeflection Test methodology.

3. All implanted intracranial aneurysm clipsthat are documented in writing to be com-posed of titanium (either the commer-cially pure and/or the titanium alloytypes) can be accepted for scanning with-out any other testing necessary.

4. All non-titanium intracranial aneurysm clipsmanufactured 1995 or later for which themanufacturer’s product labeling continuesto claim MR compatibility may be acceptedfor MR scanning without further testing.

5. Clips manufactured prior to 1995 require ei-ther pre-testing (as per the ASTM DeflectionTest methodology) prior to implantation orindividual review of previous MR imaging ofthe clip/brain in that particular case, if avail-able. By assessing the size of the artifact as-sociated with the clip relative to the staticfield strength on which it was studied, the se-quence type, and the MR imaging parame-ters selected, an opinion may be issued byone of the site’s Level Two MR attending ra-diologists as to whether the clip(s) demon-strate significant ferromagnetic properties ornot. Access to the MR scanner would then bebased on that opinion.

6. HAVING SAFELY UNDERGONE APRIOR MR EXAMINATION (WITH ANANEURYSM CLIP—OR OTHER IM-


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PLANT—IN PLACE) AT ANY GIVENSTATIC MAGNETIC FIELD STRENGTHIS NOT IN AND OF ITSELF SUFFI-CIENT EVIDENCE OF ITS MR SAFETYOR COMPATIBILITY, AND SHOULDNOT BE SOLELY RELIED UPON TODETERMINE THE MR SAFETY ORCOMPATIBILITY STATUS OF THATANEURYSM CLIP (OR OTHER IM-PLANT). Variations in static magnetic fieldstrength, static magnetic field spatial gradi-ent, orientation of the aneurysm clip (orother implant) to the static magnetic fieldand/or static field gradient, rate of motionthrough the spatial static field gradient, etc.,are all variables that are virtually impossibleto control/reproduce. These variables maywell have not resulted in adverse event inone circumstance but may result in signifi-cant injury or death on a subsequent expo-sure. Case in point: A patient who went blindfrom interactions between the metallic for-eign body in the retina and the spatial staticfields of the MR scanner entered the magnetand underwent the entire MR examinationwithout difficulty. He only went blind on theway out of the MR scanner at the completionof the examination.

7. Barring availability of either pre-testingor prior MR imaging data of the clip inquestion, a risk/benefit assessment and re-view must be performed in each case indi-vidually. Further, for patients withintracranial clips with no available ferro-magnetic and/or imaging data, should therisk/benefit ratio favor the performance ofthe MR study, the patient/guardian should

provide written informed consent that in-cludes death as a potential risk of the MRimaging procedure prior to permitting thatpatient to undergo an MR examination.

Acknowledgments

We wish to acknowledge the assistance andsupport provided by Jeffrey Hayden, ACRMRI Accreditation Program, and Tamar Whip-ple, ACR.

References

1. Chaljub G, Kramer LA, Johnson RF III, Singh H,Crow WN. Projectile cylinder accidents resultingfrom the presence of ferromagnetic nitrous oxideor oxygen tanks in the MR suite.

AJR

2001

;177:27–30

2. ECRI hazard report: patient death illustrates theimportance of adhering to safety precautions inmagnetic resonance environments.

Health De-vices

2001

;30:311–3143. Shellock FG, Kanal E, SMRI Safety Committee.

Policies, guidelines, and recommendations forMR imaging safety and patient management.

JMagn Reson Imaging

1991

;1:97–1014. Kanal E, Shellock FG, SMRI Safety Committee.

Policies, guidelines, and recommendations forMR imaging safety and patient management.

JMagn Reson Imaging

1992

;2:247–2485. Shellock FG, Kanal E, SMRI Safety Committee.

Guidelines and recommendations for MR imagingsafety and patient management. III. Questionnairefor screening patients before MR procedures.

JMagn Reson Imaging

1994

;4:749–7516. American College of Radiology.

MRI mono-graph: safety and sedation

. Reston, VA: Ameri-can College of Radiology,

1996

7. American College of Radiology.

American Col-lege of Radiology standard for performing and

interpreting magnetic resonance imaging (MRI).

Reston, VA: American College of Radiology,

2000

8. Jarvik JG, Ramsey S. Radiographic screening for or-

bital foreign bodies prior to MR imaging: is it worthit? (editorial)

Am J Neuroradiol

2000

;21:245–2479. Seidenwurm DJ, McDonnell CH III, Raghaven

N, Breslau J. Cost utility analysis of radiographicscreening for an orbital foreign body before MRimaging.

Am J Neuroradiol

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;21:426–43310. Kanal E, Gillen J, Evans JA, Savitz DA, Shellock

FG. Survey of reproductive health among femaleMR workers.

Radiology

1993

;187:395–39911. American College of Radiology.

American Col-lege of Radiology standard for adult sedation/an-algesia.

Reston, VA: American College ofRadiology,

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:res. 1712. American College of Radiology.

American Col-lege of Radiology standard

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or pediatric seda-tion/analgesia

. Reston, VA: American College ofRadiology,

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:res. 3613. American Society of Anesthesiologists.

Updatedpractice guidelines for sedation and analgesia bynon-anesthesiologists

. Park Ridge, IL: AmericanSociety of Anesthesiologists, August

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14. American Society of Anesthesiologists.

Guidelines fornon-operating room anesthetizing locations.

ParkRidge, IL: American Society of Anesthesiologists,

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Standardsfor basic anesthetic monitoring

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Stan-dards for post anesthesia care.

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17. Joint Commission on Accreditation of HealthCare Organizations.

Standards and intents for se-dation and anesthesia care: comprehensive ac-creditation manual for hospitals

. Chicago: JointCommission on Accreditation of Health Care Or-ganizations,

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Drugs and Contrast Media.

Manual on contrastmedia

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The reader’s attention is directed to the commentary on this article, which appears on page 1349.

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APPENDIX 1: Personnel and Zone Definitions

Personnel

Non–MR Personnel: Patients, visitors, or facility staff who do not meet the criteria of Level One or Level Two MR Personnel.

Level One MR Personnel:Individuals who have passed minimal safety educational efforts to ensure their own safety as they work within Zone III regions will be re-

ferred to as Level One MR Personnel (e.g., M.R.I. department office staff, patient aides).

Level Two MR Personnel:Individuals who have been more extensively trained and educated in the broader aspects of MR safety issues including issues related to the

potential for thermal loading/burns, direct neuromuscular excitation from rapidly changing gradients, etc., will be referred to as Level Two MRPersonnel (e.g., M.R.I. Technologists, Radiologists, Radiology Department nursing staff).

Zones

Zone I: This includes all areas that are freely accessible to the general public. This area is typically outside of the MR environment itself,and is the area through which patients, health care personnel, and other employees of the MR site access the MR environment.

Zone II: This area is the interface between the publicly accessible uncontrolled Zone I and the strictly controlled Zone III (see below). Typ-ically the patients are greeted in Zone II and are not free to move throughout Zone II at will, but are rather under the supervision of MR Per-sonnel. It is in Zone II that the answers to MR screening questions, patient histories, medical insurance questions, etc., are typically obtained.

Zone III:This area is the region in which free access by unscreened Non–MR Personnel and/or ferromagnetic objects and equipment can result in se-

rious injury or death as a result of interactions between the individuals/equipment and the MR scanner’s particular environment. These interac-tions include but not limited to those with the MR scanner’s static and time varying magnetic fields. All access to at least Zone III is to bestrictly restricted, with access to regions within it (including Zone IV) controlled by, and entirely under the supervision of, MR Personnel.

Zone IV:This area is synonymous with the MR scanner magnet room itself; Zone IV, by definition, will always be located within Zone III as it is the

MR magnet and its associated magnetic field, which generates the existence of Zone III itself.

Non–MR Personnel should be accompanied under the immediate supervision and visual contact with one specifically identified Level TwoMR Person for the entirety of their duration within Zone III or Zone IV restricted regions.

Level One and Two MR Personnel may move freely about all zones.


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APPENDIX 2: Safety Screening Form for MR Procedures

Date_________ Name_(first middle last) _____________________________________________ Female [ ] Male [ ] Age_______ Date of Birth______________ Height_______ Weight_______

1. Why are you having this examination (medical problem)?______________________________________

2. Have you ever had an MRI examination before and had a problem?----------------------------------------------If yes, please describe____________________________________________________________

3. Have you ever had a surgical operation or procedure of any kind?------------------------------------------------If YES, list all prior surgeries and approximate dates: ___________________________________ ______________________________________________________________________________

4. Have you ever been injured by a metal object/foreign body (e.g., bullet, BB, shrapnel)?---------------------If YES, please describe_____________________________________________________________________________________________________________________________

5. Have you ever had an injury from a metal object in your eye (metal slivers, metal shavings, other metal object)?---------------------------------------------------------------------If YES, did you seek medical attention? ---------------------------------------------------------------------------------Describe what was found _________________________________________________________

6. Do you have a history of kidney disease, asthma, or other allergic respiratory disease?------------------------

7. Do you have any drug allergies?----------------------------------------------------------------------------------------If Yes, please list drugs ___________________________________________________________

8. Have you ever received a contrast agent/x-ray dye used for MRI, CT, or other x-ray or study?--------------------

9. Have you ever had an x-ray dye or magnetic resonance imaging (MRI) contrast agent allergic reaction?-----------If YES, please describe____________________________________________________________ _______________________________________________________________________________

10. Are you pregnant or suspect you may be pregnant?----------------------------------------------------------------

11. Are you breast feeding?-------------------------------------------------------------------------------------------------

12. Date of last menstrual period_________ Post-menopausal?------------------------------------------------------

YES NO____ ____

____ ____

____ ____

____ ________ ____

____ ____

____ ____

____ ____

____ ____

____ ____

____ ____

____ ____

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APPENDIX 3: MR Hazard Checklist

THE FOLLOWING ITEMS MAY BE HARMFUL TO YOU DURING YOUR MR SCAN OR MAY INTERFERE WITH THE MR EXAMINATION.

Please mark on the drawings provided the location of any metal inside your body or site of surgical operation.

You must provide a Yes or No for every item. Please indicate if you have or have had any of the following:YES NO____ ____ Any type of electronic, mechanical, or magnetic implant. (Type________) ____ ____ Cardiac pacemaker____ ____ Aneurysm clip(s)____ ____ Implanted cardiac defibrillator____ ____ Neurostimulator____ ____ Biostimulator (Type __________________)____ ____ Any type of internal electrode(s) or wire(s)____ ____ Cochlear implant____ ____ Hearing aid____ ____ Implanted drug pump (e.g., insulin, Baclofen, chemotherapy, pain medicine)____ ____ Halo vest____ ____ Spinal fixation device____ ____ Spinal fusion procedure____ ____ Any type of coil, filter, or stent (Type__________________)____ ____ Any type of metal object (e.g., shrapnel, bullet, BB)____ ____ Artificial heart valve____ ____ Any type of ear implant____ ____ Penile implant____ ____ Artificial eye____ ____ Eyelid spring____ ____ Any type of implant held in place by a magnet (Type___________________)____ ____ Any type of surgical clip or staple____ ____ Any I.V. access port (e.g., Broviac, Port-a-Cath, Hickman, Picc line)____ ____ Medication patch (e.g., Nitroglycerine, nicotine)____ ____ Shunt____ ____ Artificial limb or joint (What and where_________________________)____ ____ Tissue expander (e.g., breast)____ ____ Removable dentures, false teeth or partial plate____ ____ Diaphragm, IUD, Pessary (Type________________________)____ ____ Surgical mesh (Location_____________________)____ ____ Body piercing (Location______________________)____ ____ Wig, hair implants____ ____ Tattoos or tattooed eyeliner____ ____ Radiation seeds (e.g., cancer treatment)____ ____ Any implanted items (e.g., pins, rods, screws, nails, plates, wires)____ ____ Any hair accessories (e.g., bobby pins, barrettes, clips)____ ____ Jewelry____ ____ Any other type of implanted item (Type_____________________)

I attest that the above information is correct to the best of my knowledge. I have read and understand the entire contents of this form and Ihave had the opportunity to ask questions regarding the information on this form.

Patient signature_____________________________MD/RN/RT signature_________________________ Date___________Print name of MD, RN, RT_______________________


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APPENDIX 4: Instructions for the Patients

1. You are urged to use the ear plugs or headphones that we supply for use during your MRI examination since some patients may find the noise levels unacceptable and the noise levels may affect your hearing.

2. Remove all jewelry (e.g., necklaces, pins, rings).3. Remove all hair pins, bobby pins, barrettes, clips, etc.4. Remove all dentures, false teeth, partial dental plates.5. Remove hearing aids.6. Remove eyeglasses.7. Remove your watch, pager, cell phone, credit and bank cards, and all other cards with a magnetic strip.8. Remove body piercing objects.9. Use gown, if provided, or remove all clothing with metal fasteners, zippers.

APPENDIX 5: Hazard Checklist for MRI Personnel

For MRI Office Use OnlyPatient Name____________________________________Patient ID Number_______________ Referring Physician______________________Procedure_________________________ Diagnosis____________________________Clinical History__________________________________________________________

Hazard Checklist for MRI PersonnelYES NO____ ____ Endotracheal tube____ ____ Swan-Ganz catheter____ ____ Extraventricular device____ ____ Arterial line transducer____ ____ Foley catheter with temperature sensor and/or metal clamp____ ____ Rectal probe ____ ____ Esophageal probe____ ____ Tracheotomy tube____ ____ Guidewires

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