Operating the MR System is an important responsibility. The systems are often multi-million dollar pieces of equipment that require special training and special safety procedures. The certification procedure described below is in force to ensure the safety of all concerned, faculty, staff and patients alike. Safety must be your number one concern at all times while operating this equipment.
Please contact Lisa Brownchidle to schedule an appointment for your MR Safety Test
Email: firstname.lastname@example.org; Phone: 313-745-1395
Part I General Information (PDF Version)
Part II MRI Orientation and Training Program (PDF Version)
Part III MRI Safety Study Guide (PDF Version)
Section I: The Magnetic Environment (PDF Version)
Section II: Contraindications for MRI (PDF Version)
Section III: Emergency Procedures (PDF Version)
Section IV: The Scanner and Related Equipment (PDF Version)
Section V: Data Acquisition and Management (PDF Version)
Part IV MR Operator Training (PDF Version)
Part V MR Safety Exam (PDF Version)
1. Before anyone (staff, subject, visitor) may enter the magnet room, a screening form must be completed and reviewed by the research technologist, research nurse, or the PI who will be performing the MRI exam.
2. Before entering the magnet room, everyone must remove from their person and clothing, watches, pagers, wallets, pens, pencils, hair/money clips, jewelry, keys, coins and any other possible projectiles.
3. Street clothes may be worn by the person being scanned if the clothing is without metal fasteners (i.e. Jogging suit).
4. The magnet room door should be kept closed at all times except when entering or exiting the room. (Keeping the door shut tight will reduce rf noise.)
5. All persons scanned must wear ear protection. If they decline, the exam must be canceled.
6. Never scan with an unplugged surface coil in the bore of the magnet.
7. Use of any research equipment, coils, or supplies not supplied by the MR Research Facility must be approved by the MR Steering Committee.
8. All investigators must clean up after themselves. Return all equipment to its proper place. The room should be kept neat and tidy. Do not lay coils and phantoms on the floors.
9. Please report all malfunctioning or damaged equipment to the research technologist or other facility core personnel immediately.
10. All studies should be archived immediately after the exam is complete.
11. A physician or nurse must be available to cover MR research exams where patients are being scanned or contrast is being administered. For normal volunteers, no medical coverage is necessary, unless contrast or sedation is being administered. However, the researcher must be familiar with code procedures and calling 117 if a medical emergency should arise.
11. Subjects must never be left unattended in the magnet. If the researcher or technologist must leave the area then he/she must get another qualified researcher to cover for him/her during the absence.
12. Subjects should never be left alone while lying on the scan table outside of the magnet. Due to the lack of side rails on the table, there is a risk of the subject falling.
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MRI Orientation and Training Program
To ensure a safe and knowledgeable working environment, all potential MR operators must complete formal training as outlined below. Upon satisfactory completion of this orientation program, only those deemed "Qualified Operators" by the MR Steering Committee will be assigned a one year safety certificate.
Each researcher and staff will complete an orientation in the MR facility via a walk through, demonstration of the equipment, and safety procedures. All orientation sessions will be supervised and documented.
Orientation/Training will include:
MRI Safety Study Guide
Section I: The Magnetic Environment
1. The Magnetic Field
It is important to remember when working around a superconducting magnet that the magnetic field is always on. Under normal working conditions the field is never turned off. Therefore, it is important to be aware of safety issues regarding ferrous projectiles and patients who may have contraindicated devices implanted in their bodies.
There are two units used to describe magnetic field strength. They are the Tesla and the Gauss. One Tesla (T) equals 10,000 Gauss. The strength of the magnetic fields of our magnets in the WSU MR Research Facility currently are 1.5 Tesla or 15,000 Gauss, 3.0T or 30,000 Gauss, 4.7T (small bore animal magnet) 47,000 Gauss and 7T or 70,000 Gauss. Our magnets are approximately 30,000 to 140,000 times stronger than the earth's magnetic field.
The five gauss line is the area at which the magnetic field becomes dangerous. For our 1.5T systems the five gauss line is indicated by orange tape on the floor of the magnet room. For our 3T system the five gauss line is located at the control room wall in the scanner room and in the equipment room the wall closest to the scanner room. For our 4.7T system, the five gauss line is at the hallway entrance door to the console room and is larger than five gauss at the entrance to the 4.7T magnet itself.
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2. Keep Doors Closed!
The doors leading to the magnet rooms should be closed at all times except when entering or exiting the room. This will prevent people who do not belong in the room from mistakenly wandering into the room.
3. Consent and Screening Procedures
Because we are a research facility we have several researchers who perform non-FDA approved MRI sequences on patients and volunteers. These sequences are important to the advancement of the science of MRI. We must, however, inform the patients and volunteers that we are performing these non-approved sequences on them and they must give us their informed consent to do so. In addition, the consent form must be signed by the Principal Investigator or their designee. Only one consent form is needed per exam, but the subject must sign a new consent form every time they return for another exam unless the consent form stipulates more than one exam. The PI or hisis/her designee is responsible for obtaining the consent. A copy of the signed consent must be signed by the appropriate WSU staff or designee before any subject can be scanned.
As stated earlier, the magnets have a very strong magnetic field surrounding them which has the potential to attract certain types of metal. The magnetic field can also interfere with the normal operation of electronic devices. For these reasons, we must have a detailed health history for every person that enters the magnet room. This includes all staff members, investigators, patients, and volunteers. The repercussions associated with a patient, volunteer, or staff member being injured because of negligence on the part of the scanning investigator could be severe and could cause research to be halted at this facility.
Screening forms have been designed and must be completed by every person entering the magnet room. For persons who are employed by this facility, the form only needs to be completed once. In the event that a staff member has an accident or surgery where a metallic foreign object or electronic device is implanted into their body, the staff member would be restricted from going into the magnet room until the metallic/electronic object can be cleared for safety purposes. It is up to the staff member to be aware of such circumstances and to report any such events to their direct supervisor.
**From this point on patients and volunteers will be referred to as "subjects". However, it should be noted that the word "patient" refers to any person scanned in the research facility who is under a physician's care.
Subjects who return for another MR exam must fill out a new screening form each time they visit. The screening form must be signed by the subject and the investigator or technologist who is performing the scan (if listed as one able to sign the consent form). The signed screening form will be kept on file in the WSU MR Research Facility Coordinator's office. Blank screening forms can be found in the file drawer in the 1.5T and 3T control room.
Keep in mind that all subjects who are giving information regarding their health history must be conscious and coherent. Any gaps in memory or lack of information about a surgical procedure is grounds for canceling the subject, unless a family member can provide a detailed history. If there is ever any question about a subject's past health history regarding metal in their body, it is required that the MR exam be put on hold until the question can be investigated thoroughly.
An in depth explanation of contraindications to MRI will follow in the next section.
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Section II: Contraindications for MRI
There are several types of contraindications that would prevent a subject from having an MRI scan. Metallic implants and foreign bodies as well as the subject's physical condition will be discussed in this section. All subjects are required to remove any clothing that has metal on it. Gowns are provided for the subject to change into. All subjects and staff members must empty their pockets of any loose metallic objects (hair pins, safety pins, coins, keys, ID badges, wallets, credit cards, banking cards, lighters, pocket knives, scissors, stethoscopes, hemostats, etc.) before entering the magnet room.
1. Surgical Implants
There are hundreds of metallic implants that can be surgically placed into a person's body for various reasons. Some of these implants are ferrous and may be attracted to the magnetic field. Some may be electronic in nature, in which case, the magnetic field can interrupt the device's normal operations. Worse, by placing an electronic device in the magnetic field, a current may be induced in the conducting wires of the device which could possibly burn the patient. There are many metallic implants that are non-ferrous and may be compatible for MR such as orthopedic screws, rods, and plates. It is suggested that a waiting period of at least six weeks after surgery is necessary for the tissues around the implant to take hold of it to prevent any potential movement of the implant. Although the six week period is generally observed, in some more emergent instances a subject with a non-ferrous implant may be scanned as soon as a day after the implant is in place. There are also some ferrous implants (e.g., heart valves, venous blood clot filters) that are compatible for MR. Typically the waiting period for these implants is six weeks. The bottom line is that the waiting period decision should be left to a Radiologist who is familiar with the implant and its magnetic properties. To prevent injury to the subject, it is extremely important that the scanning investigator be familiar with the difference between compatible and contraindicated implants and devices.
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2. Accidental Metallic Foreign Bodies
Occasionally an investigator may have a subject tell them they have been injured by a piece of metal which punctured their body in some way, shape, or form. Common causes of this type of injury are people being shot with bullets, buckshot, pellets, or BB's. Other frequent causes are people who work with grinding, sanding, or cutting metal frequently are exposed to metal slivers flying off of the metal piece they are working with. These metal slivers often fly into the eyes, hands, or face. People who have been involved in wartime activity may have pieces of shrapnel or other metal fragments in their body. Any of these circumstances must be investigated thoroughly to prevent injury to the subject.
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3. Checklist of Tested Implants, Devices, and Metallic Foreign Bodies
Located in the MR Facility is a small handbook entitled Reference Manual for Magnetic Resonance Safety 2002 Edition . This book lists hundreds of surgical implants and metallic foreign bodies which have been tested by leading MR safety authorities in magnetic environments for evidence of deflection and torquing of the metallic objects. This book should be used to investigate any questionable implant or foreign body. Additional safety articles are available in the Research Coordinator's office.
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4. Procedure to Clear Metallic Implants and Foreign Bodies
The subject should be asked about their surgical or accident history. In addition to this, the investigator should re-question the subject about their history even if the subject has stated that they have not had any surgery. It is not uncommon for a subject to conceal or forget about a procedure or accident which may have happened long ago. Further questioning the subject and explaining to them the importance of their honesty for their own safety can sometimes provide additional information to the investigator.
If you discover the subject has had a surgical implant or an accident involving metal you must find out the following:
1. What was the procedure? What was the nature of the accident?
2. What kind of implant is it? Name of the manufacturer? What does it do? What is it used for?
3. When was the procedure done? What year?
4. Do you know for sure that it is metal?
5. Who was the doctor/surgeon who performed the procedure? Is he or she still in practice?
6. At what hospital was the procedure performed?
7. If it was an accident, did you have any x-rays done at the time and was the metal removed?
Once you have all of the answers to these questions, proceed with the following:
1. Take the information to the MR research technologist or MR Research Coordinator. They have been educated as to what may or may not be scanned and in many instances will be able to assist you.
2. If they do not know of the implant or think the subject may have to be canceled, the PI and a radiologist must be involved at this time for more information. If the subject doesn't know if the implant is metal, the radiologist may suggest x-rays be done to rule out metal. X-rays may not be performed without the permission of the Principal Investigator and the subject.
3. If the radiologist does not know of the implant, you must contact the surgeon who placed the implant and request a copy of the operating room report which should describe the model and name of the implant. This report will be attached to the subject's screening questionnaire for permanent documentation.
4. The final responsibility of canceling or proceeding with the exam lies with the Principal Investigator who should make an informed decision based on the information provided by the MR Research Facility Staff and radiologists.
5. If the subject is cleared, a written permission signed by the Principal Investigator for the subject to undergo the MR exam must be provided to the MR Research Facility. This permission form will be attached to the subject's screening questionnaire for permanent documentation.
Any person (subject or staff) who has a history of working with metal as an occupation or hobby should have x-rays of their orbits to rule out metallic foreign body before they enter the magnet room. The only case of a patient being blinded by a metal sliver piercing their optic nerve was a former metal worker who did not know that he had a piece of metal in his eye.2 Typically if metal workers get a sliver of metal in their eye, it is removed in an emergency room by a physician. However, without x-rays, there is no way of knowing if the entire piece of metal was removed. Usually x-rays will be ordered at the time the metal is taken out. If we can obtain a copy of the report from those x-rays, and the subject has not gotten any more metal in their eyes since the x-rays were taken, then we may use the original x-ray report to clear the subject for the MR exam.
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5. Emergency Removal of the Subject from the MRI Scanner
If the investigator has placed a subject in the scanner and upon looking at the first set of images notices a metallic artifact present, the investigator must follow the proper procedure for removing the subject from the scanner and the magnet room.
1. Tell the subject you are going to remove them from the magnet. Instruct them to remain perfectly still and to not sit up at any time.
2. Pull the table out of the scanner very slowly.
3. Move a gurney into the magnet room and place it next to the table.
4. Have the subject slide, without sitting up, onto the gurney.
5. Slowly pull the gurney straight away from the magnet without turning the gurney.
6. Once you reach the doorway slowly turn the gurney and move it out through the doorway.
7. Once the subject is safely outside of the room, they may sit up.
** This procedure should also be used if the subject tells you of a contraindicated metallic implant in their body after they have already been placed in the magnet.
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6. Pregnant Subjects
It is the policy of the MR Research Facility not to scan any pregnant subjects for research purposes. In the clinical environment, pregnant patients are only scanned in emergency situations. With this in mind, and realizing that research is not done on an emergency basis, pregnant subjects must wait until after they give birth to participate in a research project.
If a subject believes she may be pregnant, it is up to the Principal Investigator decide if the subject should undergo a pregnancy test. If the PI deems a pregnancy test is necessary, all arrangements and financial responsibility will be taken care of by the PI or their designee.
If the pregnancy test is negative and the subject is to undergo the MR, a copy of the pregnancy test report will be needed by the MR staff to attach to the subject's screening questionnaire for permanent documentation.
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7. Contrast Agents used in Subjects who are Breastfeeding
In the case where a research subject is breastfeeding her child, the mother must be informed that her milk must be expressed with a breast pump and thrown away for 48 hours following the injection of gadolinium contrast agent. It is important that she be aware of this in order that she may, ahead of time, store enough milk to feed the child during the 48 hours after the contrast injection.
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8. Pregnant Staff
It is the policy of the MRI Research Facility that all pregnant staff members be restricted from the magnet room when radiofrequency pulses are on. Any pregnant ancillary staff member (nurses, coordinators, secretaries) who do not need to be in the magnet room should stay out of the room unless there is an emergency with a subject. Pregnant staff members, such as MRI technologists, who must enter the room on a regular basis should only stay in the room as long as necessary i.e., positioning subjects, emergencies, etc.
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9. Radiofrequency and Specific Absorption Rate
MR employs radiofrequency (RF) pulses to disturb the alignment of protons in the nucleus of hydrogen molecules in the body. These RF pulses deposit heat into the tissues of the body. This heat deposition is termed Specific Absorption Rate or SAR. SAR is measured in watts per kilogram and is a function of several variables, including: (1) the type of RF pulse used (90 or 180 degrees); (2) the number of RF pulses in a sequence; (3) the pulse width; (4) the TR; (5) the weight of the patient; and (6) the type of coil used.3 The FDA has developed guidelines to regulate the amount of deposited heat that are within acceptable limits. Currently all manufacturers of MR equipment are required to submit their pulsing sequences to the FDA for SAR review
Conditions in the examination room
Ambient temperature: 21oC, +3 oC
Relative Humidity: 50% - 70%
Old Specific Absorption Rates (SAR)
Levels insufficient to produce a core temperature increase in excess of 1oC and localized heating to greater than 38oC in the head, 39oC in the trunk, and 40oC in the extremities.
< 3.2 W/kg averaged over the mass of the head
< 1.5 W/kg whole body average for all subjects
< 3.0 W/kg whole body average for subjects with normal functioning thermoregulatory systems
< 8.0 W/kg spatial peak in any one gram of tissue
** It should be noted that subjects with thermoregulatory illnesses such as fever, or diseases in which the patient is unable to sweat, may be compromised by heat deposition in MR. Extreme care should be taken with these subjects to keep them cool during the exam. You should investigate choosing sequences that do not result in high amounts of heat deposition. Also, the eyes are particularly susceptible to heat deposition.
Current Specific Absorption Rates (SAR)
There are three specific absorption rate limits:
Whole-Body SAR Limits
Head SAR Limits
Local SAR Limits
Local SAR, or hot-spot SAR, is the value of the SAR averaged over the most exposed 1 gram of tissue.
Slew Rates and Stimulation
On April 21, 1995, CDRH released a draft for public comment which contained revisions to the original MRDD Guidance relating to operation at dB/dt levels beyond the levels of concern listed in that document. A public meeting of the Radiological Devices Panel was held on September 11, 1995 to discuss the proposed revisions, and a final version was issued on October 11, 1995
The original MRDD Guidance had established a level of concern for dB/dt at 20 T/sec for pulse duration over 120 microseconds. As an alternative, a manufacturer could demonstrate that the rate of change of the gradient field was not sufficient to cause peripheral nerve stimulation by an adequate margin of safety. The development of echo planar and similar fast imaging techniques, and the clinical benefits which they provide, caused a re-evaluation of this policy. Evidence was presented that although peripheral nerve stimulation could potentially startle a patient and cause motion which could interfere with image acquisition, the sensation is not harmful. However, painful stimulation should be avoided.
The Guidance Update for dB/dt recommended that manufacturers of equipment which exceeds 20 T/sec conduct volunteer studies to determine if peripheral nerve stimulation is possible with their device. If so, the device should incorporate a warning to the operator below the level at which stimulation begins to occur. Acknowledgment of the warning by the operator should then be necessary to proceed with the scan. Instructions for use should advise the operator to inform the patient when nerve stimulation is possible, and describe the nature of the sensation to the patient. Equipment intended for routine clinical use should be limited so that painful stimulation is not induced.
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Section III: Emergency Procedures
1. CPR Requirements
It is a requirement of the MR Research Facility that all facility staff who will be conducting MR experiments on humans will be certified in Cardiopulmonary Resuscitation (CPR). We strongly encourage all PIs, their staff and students also be certified. For your convenience the MR Research Coordinator is a certified CPR instructor and usually offers classes once or twice a year. Please contact her for more details. (51393)
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2. The Crash Cart
There is one crash cart located in Radiology. During the day it is located in Angiography and at night in the hallway between Cat Scan and Patient Holding.
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3. Code Procedures
In order to know the status of the subject at all times, it is strongly recommended that the pulse oximeter be placed on the finger of every subject that goes into the magnet. This will provide you with a heart rate and oxygen saturation for the subject while they are in the scanner. If the subject becomes unresponsive begin the code procedure as listed below.
1. Immediately remove the subject from the magnet room.
2. Dial 117 and state the following twice: "
3. Start CPR if you know how.
4. When the code team arrives step out of their way.
5. Provide the code team with any information they may request regarding the subject if known.
Please note because our facility is located within a hospital environment all PIs, their staff and students must be inserviced on the hospital's emergency preparedness plan and environment of care yearly. Our Research Coordinator offers these inservices several times a year for your convenience (please contact her for details 51393).
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The term "quench" is used to describe the rapid boil off of the cryogens that keep the magnet cooled and in a superconducting state. Cryogens are supercooled liquid gases. All our systems require liquid helium to keep them cool. Without cryogens, the magnet loses its magnetic field. Usually a quench is undesirable and is due to a malfunction within the system. In rare instances a quench may be necessary to free someone from the magnet if they have been accidentally struck by a projectile ferrous object and pinned to the magnet. In each control room there are boxes on the wall that enclose quench buttons that should be pushed in the event that the magnetic field must be manually run down.
When a quench occurs, either spontaneously or manually, you must evacuate from the magnet room immediately to avoid being overcome by the helium gasses should they not vent properly out of the room. If you are going to manually quench the magnet, make sure the door to the scan room is left open to avoid a vacuum forming which may seal the door shut. If the magnet quenches spontaneously, and you are unable to open the door, you must break the window between the control room and the magnet room in order to get the subject out of the room.
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5. Projectile Injury
If a subject or staff member becomes pinned to the magnet by a ferromagnetic object, you must evaluate the situation quickly before taking any action. If the person is unconscious, bleeding profusely, at risk of losing a limb or extremity, or in severe pain, you must manually quench the magnet to bring down the field in order to release the object and the person. If the person is responsive and able to tell you they feel O.K., you may be able to leave them in the position until a service engineer can respond and ramp the magnet down slowly to avoid a full quench. If you choose the latter, and the person then loses consciousness, or their condition worsens, immediately quench the magnet manually. Keep in mind that the cryogens are expensive to replace so evaluate the situation carefully but never put cost above the life or well being of the person.
Once the person is released, get them out of the room and obtain medical help or begin the Code Blue procedure. Remember when in doubt it is always better to call a Code Blue than not.
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6. Responsible Parties
Any time a patient is scanned, or any contrast agent or drug is administered to a human in the MR Research Facility a physician and/or nurse must be available to cover in the event of a medical emergency. If the PI is not a medical doctor, arrangements must be made to have a medical doctor and/or nurse available to respond for emergency purposes. If a designee of the PI is present with the subject, the designee must know how to reach the PI, or a medically responsible party, immediately in the case of emergency. The MR Research Facility will assume these arrangements have been made before the subject is scanned and will not be responsible for medical treatment of the patient other than proper emergency procedures, in the event of an emergency or adverse event.
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Section IV: The Scanner and Related Equipment
1. Startup and Shutdown Console Control Computers for the 1.5T Sonta
Function check before switch on/switch off:
Is the display of the alarm box functioning?
Are all warning signs posted?
Are there fluids on the floor?
Is the patient table outside of the magnet bore?
Bringing the MRI computer up, or booting the computer, is a fairly simple procedure. If you come in to a black screen simply press any key or move the mouse and you will get into the normal operation mode (syngo).
From this point on, in order to use the scanners, you must have been approved by the research committee for scan time on the research magnets.
Caution: You must not operate the patient table while syngo MR is starting up.
If the screen remains black, STOP and contact the technical support staff to help.
If you are trained on the start-up and shutdown perform the following:
Turn the key in the alarm box 90 clock wise
Press the System On button
The System On LED at the alarm box lights up. The system is switched on. At the control computer, Windows NT and syngo MR are booted automatically.
Switching on standby mode:
In standby mode the measuring unit and patient table are switched off. The control computer (HOST) is operational. You can evaluate and report but not scan.
Press the Host Standby button of the alarm box.
If the system is switched on, all the components except for the HOST computer are switched off.
If the system is switched off, only the HOST computer is switched on.
If you press the System On button in standby mode the system is again ready for scanning.
Switching the system off:
First close syngo MR, then shutdown the system.
Select System>End, select Shut Down All, then confirm with OK.
if the message " It is safe to turn off your computer" appears:
Press the System Off button on the alarm box
Turn the key switch counter clockwise.
The system is now locked.
**Restart is used when there has been a problem with the system software (screen freezes, image recon, scan control, etc.) but you would like to continue to scan after the system comes back up.
*end application will end the processes that you are working on without shutting down the entire system.
*end system will bring down the Numaris software.
**NOTE: The systems can also be brought up and down by pressing the startup and shutdown buttons on the wall in the control room.
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2. Table Controls & Table Stop Buttons
Each of the magnets is equipped with a table that moves into and out of the scanner by using the joy sticks on the front of the magnet gantry. On both sides of each table are red table release buttons. Normal position for the buttons is in the OUT position. To remove the table rapidly, you only have to push one of the red buttons IN on ether side of the table or on the microphone in the control room. The table may then be pulled out of the magnet bore manually.
To reset the table, pull joy stick down all the way and then move the joy stick all the way up, now table is reset.
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All subjects are required to wear ear protection while undergoing an MR exam. Earplugs and headphones are provided. Not only do the headphones serve as a communication device they are also part of the noise cancellation system which helps to drown out the knocking noise of the gradients. If the subject refuses all hearing protection, the scan cannot be performed.
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4. Communicating with the Subject While They are in the Scanner
It is important to maintain voice contact with the subject throughout the exam. The researcher should routinely establish contact between each sequence.
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5. The Patient Alarm
Every subject should be given the patient alarm ball to hold in their hand during the exam. The subject should be instructed to squeeze the ball if...
They need to speak with the investigator in between sequences.
They want to come out of the scanner immediately.
Something is hurting them.
Because the scanner cannot be put in a pause mode, if you stop a scan to speak to the subject, you will have to start the scan all over again from the beginning. For this reason, it is wise to advise the subject to squeeze the ball only in situations of pain, injury, or claustrophobia. If the investigator is communicating with the subject routinely between sequences, the subject will be less likely to squeeze the ball in the middle of a sequence to ask a non-emergent question.
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6. The Invivo Monitoring System
The MR Research Facility has purchased an excellent MRI compatible monitoring system for use during MR exams. With this system we are able to do the following:
1. Obtain an ECG trace from the subject.
2. Obtain blood oxygen saturation percentages from the subject.
3. Obtain blood pressures from the subject.
ECG & Cardiac Gating
Currently there are several types of studies where cardiac gating is desirable. Cardiac gating functions to allow imaging in areas of the body where there is considerable motion. For example, when imaging the heart, cardiac gating is used to tell the computer to image all of the slices at the same point in the heart cycle every time the heart beats. This gives the appearance that the heart motion is frozen resulting in images with the appearance of little or no motion artifact.
Special attention must be give when attaching the electrode and leads to the subject's chest. Because you are placing the lead wires in a magnetic field, it is possible to induce an undesirable current in those wires which may burn the subject. It is imperative that the lead wires and the main ECG cable have no loops in them when placed on the subject. The main cable should not touch the sides of the magnet or the subject's skin as it is run out of the magnet bore. The cable should be run straight out of the bore with no loops and should not cross over the subject's body at any point. If you must get the cable from the subject's left side to the plug-in port on the right side of the table, run the cable down the left side of the subject, and then across the foot of the table. A washcloth, sheet or towel must be placed between the subject's skin and any wire that makes contact with the skin. If the subject has an IV in place do not cross the ECG cable or wire over the IV tubing.
Blood Pressure Monitor
The blood pressure monitor is able to measure the subject's blood pressure non-invasively at prescribed intervals throughout the exam. The researcher may set a time interval at which the monitor will automatically inflate the cuff on the subject's arm while the subject is in the scanner. An updated BP reading is displayed with each interval's measurement.
The blood pressure cuff may be placed on either arm, but care should be taken not to place it on an arm which has an IV placed in it. Also, it is not uncommon for women who have undergone a mastectomy to have poor lymph circulation in the arm on the side of the mastectomy. Because of this, these subjects cannot usually withstand pressure placed on the arm of the same side as the mastectomy. For example, if the woman has had her right breast removed, you will want to put the BP cuff on her left arm. If she has had both breasts removed, ask her on which arm she prefers to have the cuff placed or utilize the leg for BP readings.
Blood Oxygen Saturation Monitor (Pulse Oximeter)
The pulse oximeter when placed on the fingertip of the subject will display the subject's heart rate and percentage of oxygen in the blood. The pulse oximeter may be placed on any finger, however, we have found that it works best on the index or middle finger.
The corrugated cable running from the finger clip to the pulse ox monitor contains fragile fiber optic wires. It is important that this cable is not stepped on or crushed. Please be careful with it. Damage to the fiber optics or a break in the corrugated cover could cause the pulse ox to malfunction or produce RF artifacts.
**NOTE: For safety purposes, it is strongly recommended that the pulse oximeter be placed on all subjects who are having an MR exam. If the subject should fall asleep in the scanner and become unresponsive the investigator will know whether or not the subject is O.K. or in distress based on the readouts from the pulse oximeter. This will save the investigator from having to stop the experiment to go into the magnet room to check on the subject. Also, if the subject should have heart failure or a breathing difficulty, the investigator will know immediately based on the readout from the pulse oximeter.
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7. Removing Subjects from the MR Scanner
If a subject requests to be removed from the magnet at any time, the investigator should do so promptly. Whether it be because of pain, illness, or claustrophobia, the investigator or technologist must never keep the subject in the MR scanner against their will. If a subject asks to be brought out, communicate with them to determine the problem. You may ask the subject if they can continue. If not, remove the subject immediately.
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8. Starting a Scan/Stopping a Scan in Progress address procedure for all scanners
To start a scan simply click on the "measurement" button on the control screen. If the scan has been "loaded", click on the "start" button to begin the scan. To stop a scan click on the stop button on the control screen.
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9. Oxygen/Suction/Room Air Supplies
Both 1.5T and the 3T scanner rooms are equipped with oxygen, suction, and room air channels. In the 1.5T, they are mounted on the wall to the left of the scanner. In the 3T they are mounted on the wall to the right of the scanner. Oxygen is marked by the green hose or regulator, suction is white, and room air is yellow.
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Section V: Data Acquisition and Management
1. Responsibility for Acquired Data, Archiving, & Deletion of Data
All investigators are responsible for the data they acquire. Data must be archived immediately after the exam is complete in order to prevent loss of data by removal from the MR system disks.
Data may stay on the MRI system disks for up to seven days. ( What limits do you wish to place on on this?) It is requested that if the investigator does not need the data or is finished processing it, the data be removed. If the disks become full and deletion is necessary, the oldest studies will be removed first.
If an investigator needs their data to stay on the disks for longer that seven days they will need to contact the MR research technologist and let him/her know how long it will be before they will archive their data. Investigators may only remove their own data. All other MR data may only be removed from the system disks by the MR research technologist.
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Part IV MR Operator Training
MRI Operator's Exam
1. Mr. Jones is feeling a little claustrophobic during his exam and would like his wife to sit with him during his MRI exam. Mrs. Jones had a pacemaker implanted five years ago therefore it is permissible to allow her into the room now as long as she stays at least 10 feet from the front of the magnet.
2. For subject safety purposes, which of the following items are contraindicated for an MRI scan.
a. orthodontic braces.
b. orthopedic screws in the ankle placed 6 months ago
c. aneurysm clips
d. pacer wires (no pacemaker) left in the chest after open heart surgery 3 years ago.
e. c & d only
f. all of the above
3. You walk into the scan room and find a maintenance employee pinned to the magnet by a floor buffer. He is unresponsive but has a weak pulse. You immediately...
a. Throw cold water on him.
b. Use smelling salts to try to rouse him.
c. Call his supervisor and tell him that the maintenance employee is sleeping on the job.
d. Call for help then attempt to free the employee. If unsuccessful, press the quench button to eliminate the magnetic field
4. While scanning a subject for a heart study, he suddenly complains of a stinging, burning sensation at the location of one of the electrodes placed on his chest for cardiac gating. You....
a. Tell him to remain quiet until the sequence has finished.
b. Turn the radio up louder so you can't hear his complaint.
c. Tell him the stinging will subside in a few hours.
d. Immediately remove him from the magnet and inspect the area of the leads for loose or crossed wires.
5. When positioning the ECG monitoring cable on a subject for a heart study, it is OK to run the cable across the subject's body to plug it into the connector box.
6. You have just positioned a subject inside of the magnet for a knee scan when she suddenly remembers she had a brain aneurysm repaired ten years ago. You...
a. Rapidly pull the table out of the scanner, immediately lower it, and rush her out of the room as fast as possible.
b. Continue with the exam because you are not scanning her head.
c. Call 117
d. Very slowly pull the table out of the scanner and then have the subject slowly slide onto a stretcher so that you can slowly cross her through the magnetic field lines and out of the room.
7. Which of the following is the current FDA recommendations regarding specific absorption rates for the Siemen's 1.5T MR scanner?
Are these current and applicable to both machines?
a. Not to exceed 1.5 W/kg(whole body)
b. Not to exceed 3.2 W/kg(head imaging)
c. Not to exceed 8 W/kg in any single gram of tissue
d. Not to exceed an increase of 1oC core temperature or 38oC in the head, 39oC in the trunk, and 40oC in the extremities.
e. all of the above.
8. If a subject is unresponsive when you try to communicate with him in between scanning sequences, you should...
a. Continue with the scan and assume that he is sleeping.
b. Call 117.
c. Defibrillate him.
d. Pull him out of the scanner or at the very least go into the room to see if he is O.K.
9. To avoid the confusion that may be caused by the scenario in the previous question, it is a good idea to use the pulse oximeter on everyone that is placed into the magnet.
10. Your subject has informed you that he has worked as a metal grinder for ten years but he has never had any metal shavings fly into his eyes.
a. Proceed with the scan since he has never gotten any metallic foreign bodies in his eyes.
b. Do not proceed with the scan and at the discretion of the Principle Investigator, send the subject for x-rays of his orbital area to rule out possible metallic foreign bodies.
11. Your subject has informed you that she had a metal sliver enter her eye 10 years ago but that the doctor got it all out. You...
a. Proceed with the scan since the metal sliver was removed.
b. Do not proceed with the scan and at the discretion of the Principle Investigator, send the subject for x-rays of the orbital area to rule out possible metallic foreign body.
12. While performing a brain MR on a twenty-four year old woman, she begins to complain of some stinging around her eyelids. Upon examining her you find out that she has permanent tattoo eyeliner. You...
a. terminate the exam, apply cold compresses to her eyes, and seek the proper medical attention.
b. apply ice-cold compresses to her eyes to lower the temperature in the area and then continue with the scan if she feels up to it.
c. tell the subject to shut her eyes and the pain will go away.
13. Your subject has had a heart attack while undergoing an MR exam. You ...
a. dial 117, call a Code Blue and immediately bring the crash cart into the magnet room to begin resuscitation measures.
b. dial 117, call a Code Blue and bring the subject out of the magnet room on a stretcher to begin resuscitation measures.
c. call 911 and wait for the paramedics to arrive.
d. call 117, and go and get the crash cart.
14. The red table stop buttons on both sides of the table are used to...
a. stop the table from moving.
b. set off an alarm that tells you the patient is moving around on the table during the scan.
c. release the table for manual removal of the patient during emergencies.
d. quench the magnet.
15. The red table stop buttons on both sides of the table must be in which position to release the table?
a. pushed in.
b. pulled out
16. During the middle of a measurement, you hear the subject attempting to speak to you but you cannot hear her clearly. You...
a. Ignore her and continue the measurement.
b. Stop the measurement and speak to her.
c. Stop the measurement and yell at her for interrupting.
d Terminate the entire exam.
17. Your subject tells you she had surgery twenty years ago on her brain but she can't remember exactly what it was for. You...
a. proceed with the scan because she seems credible.
b. cancel the scan for today until further investigation into the matter can occur.
c. tell the subject of the risks involved due to her lack of history and allow her to decide if she wants to have the MRI.
d. proceed with the test only after having the subject sign a waiver that releases us from responsibility of injury because after all it's not our fault she can't remember her surgery.
18. Which of the following are contraindicated for an MRI exam?
a. cardiac pacemaker
b. Swan-Ganz catheter
c. aneurysm clips
d. all of the above
19. It is acceptable to loop an insulated surface coil cable around a subject's arm or leg to help keep the cable from getting caught in the table.
20. Cryogens are...
a. industrial strength cleaners.
c. liquefied gases used to cool a superconducting magnet and are deadly to breathe.
d. sewer gases.
21. A quench is...
a. a relief of thirst for a hardworking researcher.
b. a rain cloud that occurs inside of the magnet room due to overuse of the magnet by physicists.
c. a rapid, usually undesired, release of the cryogens which causes a rapid decline of the magnetic field.
d. the German word for magnet.
22. The first thing that you should do if a quench occurs is...
a. call 117
b. call the service engineers.
c. immediately remove the subject from the scanner.
d. call the EPA
23. If during a quench the cryogens do not vent out of the room properly a vacuum may form making it difficult to open the door to the magnet room to get the subject out. If you are unable to open the door, you should...
a. sit and wait..
b. use a blow torch to burn through the door.
c. break the window between the control room and the magnet room.
24. If your subject becomes short of breath while in the MR scanner you should immediately grab the oxygen tank off of the crash cart and administer oxygen.
25. It is O.K. to let someone go into the magnet without emptying their pockets of metal objects if they are only going to be in there for less than a half hour.
26. Which of the following objects are approved for entry into the MR scanner room.
c. employee I.D. badges
d. small paper clips and coins
e. none of the above
27. The system stop key will cut power to...
a. all computer cabinets except for the gradient chiller cabinet.
b. the lights.
c. the fire alarms.
d. the automatic sprinklers.
28. If you get a message that the gradient chiller system is malfunctioning, you should immediately...
a. continue to scan because the chiller is on automatic controls.
b. run from the room screaming.
c. stop scanning to avoid overheating the gradients.
d. call 117.
29. If the subject sets off the patient alarm during the scan you should...
a. page the MR research nurse/technologist
b. tell the patient to be patient.
c. communicate with the subject to check on their status.
d. turn off the alarm and keep scanning.
30. Which of the following are contraindications for MRI?
a. cochlear implants
c. patient controlled anesthesia devices
d. all of the above
31. Pregnant women should never be scanned in our research facility.
32. Pregnant research staff members are not permitted to enter the magnet room.
33. Which of the following is the correct method of investigating a metallic implant in a subject?
a. Take the subject's word that their implant is non-ferrous.
b. Call the surgeon responsible for placing the implant and get a detailed written operating room dictation explaining where the implant was placed, what it is, what it is made of, the manufacturer, and the model name and number.
c. Ask the subject's family member.
d. Call a physician referral service.
34. Any time a patient is scanned for research purposes, a medical doctor or other qualified medical personnel associated with the study must be present or in the near vicinity, and available at all times.
35. The MR compatible monitoring system that we have available to us is capable of measuring which of the following?
a. ECG and heart rate
b. Blood pressure
c. Blood oxygen saturation
d. all of the above
36. It is O.K. to leave a subject lying on the table outside of the magnet bore while you leave the room.
37. All subjects undergoing an MRI should be given ear protection in the form of earplugs and/or the noise cancellation headphones.
38. Every person that enters the magnet room should have completed a screening questionnaire regarding metal in the body.
39. It is mandatory that research subjects remove all metal, metal jewelry, clothing with metal on it, and pocket contents before having an MRI scan.
40. Metallic objects in the body will produce an artifact on the images that looks like...
a. a black signal void with bright edges.
b. a green streak.
c. a line through the image.
d. pink swirls.
41. If caught in the magnet room during a quench where should you place your body to avoid inhalation of the cryogens?
a. On top of the scan table.
b. Perpendicular to the main magnetic field.
c. As close to the floor as possible.
d. Pressed up against the window between the scan room and the control room.
42. The simplest way to stop a measurement is to...
a. click the left mouse on the stop button on the "change" or "position" menus of the scan console.
b. quench the magnet.
c. turn the key off.
d. speak the word "stop" into the microphone.
43. Which of the following is the correct reason to shut the MRI system down (not the magnetic field).
a. Building utilities are to be shut off.
b. The scanner applications have locked up.
c. No one is going to be using the system for several hours.
d. all of the above.
44. When should the doors to the magnet rooms be shut?
a. When measurements are running.
b. Whenever the system is not in use.
c. Whenever there is the potential that someone not associated with the study will wander into the room.
d. all of the above
45. If an acquaintance of yours asks you to take them into the magnet room to look at it, what do you do.
a. Take them right in.
b. Insist that they empty their pockets and then take them in.
c. Tell them absolutely not, under any circumstances will you let them in.
d. Screen them for metal in their body as if they were a patient and if they are cleared, have them remove all loose metal from hair, pockets, and clothing, and then take them in the room.
46. All subjects must complete a consent form before having an MRI scan in the research facility.
47. A volunteer had an MRI scan six months ago and they are now participating again. What documents do they need to complete?
a. None, the ones they completed before are still good.
b. Screening form only.
c. Consent form only.
d. Consent and screening forms.
48. Under normal circumstances when the MRI scan is not an emergency, subjects who have had non-ferrous metal e.g., orthopedic screws or plates, surgically implanted must wait how long before they can undergo an MRI scan?
a. 2-6 weeks
b. 5 years
c. 1 year
49. Subjects who have metal devices which are not contraindicated for MRI i.e., heart valves, venous blood clot filters, surgically implanted, must wait how long before they can undergo an MRI scan?
a. 2-6 weeks
b. 5 years
c. 1 year
50. After completing an experiment, you should...
a. leave the room clean and tidy.
b. leave the room as you found it.
c. leave the phantoms on the floor.
d. call the technologist to clean up the room.
51. Ferromagnetic objects are dangerous to take near the magnet because...
a. they can become projectiles and harm the subject.
b. they will burn the subject.
c. they become very heavy.
d. there are too many north poles and the subject gets dizzy.
52. The leads for cardiac gating must be handled as follows.
a. wound together and routed down the center of the magnet.
b. run in parallel across the subject's chest.
c. placed on the shin of the subject.
d. coiled in a loop and placed across the subject's chest.
e. none of the above.
53. Echo-planar imaging and other sequences can be quite loud. You should...
a. tell the subject to grin and bear it.
b. have the subject cup his hands over his ears.
c. use ear plugs and/or ear phones to dampen the sound.
d. have the subject sing during the scan to dampen the sound.
54. Consent forms must be signed by all subjects when non-FDA sequences are used.
55. While scanning a subject for a heart study, he suddenly complains of chest pain. You...
a. tell him to remain quiet until the sequence is finished.
b. ignore his complaints.
c. immediately remove him from the scanner, get him out of the room, and call 117.
d. give him a drink of water and put him back in the scanner to continue the exam.
56. All ferrous devices and devices containing motors or questionable ferrous parts should be secured when brought into the magnet room.
57. The five gauss line is...
a. A pixel line in the matrix.
b. The magnetic field line territory at which the magnetic field can become harmful.
c. A catheter inserted into the femoral artery.
d. A geometric theorem.
58. Where are the five gauss lines located in our MR research facility.
a.. At the RF window/screen between the control room and the magnet room for the 3T.
b. At the orange tape on the floor between the console room wall and the 1.5T magnet.
c. At the hallway entrance door of the console room for the 4.7T system.
d. All of the above
59. When a subject is in the bore of the magnet it is O.K. for the researcher to leave the control room ...
a. to check the weather outside.
b. whenever he feels like it.
c. when he wants to get himself a soda.
d. if, and only if, he gets someone else to monitor the subject for him while he is gone.
60. Potential subjects who have magnetically controlled artificial body parts or prostheses such as artificial limbs or eyes cannot undergo an MRI exam.
61. Assume you are using the head coil to image a patient and that the next patient will have a body scan. When the patient scanning is completed and you have taken the patient out of the room you should:
a. pull the table out and carefully remove the head coil and put it away
b. rip the expensive head coil out of its support with no regard for its expense because you have to get ready for the next patient or volunteer
c. call the research tech for help
d. slide the head coil to the other end of the patient table
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Part V MR Safety Exam
TOPIC TOUR MATERIAL REVIEWED BY DATE
Patient Handling Procedures
• Screening/Safety ____________________
• Review Screening Form ____________________
• Review Consent Form ____________________
• Review Permission Form ____________________
• Monitoring Equipment
Blood Pressure ____________________
Pulse Oximeter ____________________
• Emergencies ____________________
• Code Procedures ____________________
TOPIC TRAINING MATERIAL REVIEWED BY DATE
• Coil Selection/Set up ____________________
• Positioning ____________________
• Pulse Sequence Selection ____________________
• Imaging Options Selection ____________________
• Scanner Startup/Shutdown ____________________
• Record Keeping/Documentation ____________________
• Archiving/Deletion of Data ____________________
TOPIC Training/Tour Materials REVIEWED BY DATE
• Processor Startup/Shutdown ______________________
• Laser Camera Startup/Shutdown ______________________
• Filming Software ______________________
• Developing Films ______________________
Description of Training
Accomplishments* No. of Hrs. Reviewed By Date
• Sequence Experience ________________________________
• Sequence Design (IDEA) ________________________________
• Reconstruction (ICE) ________________________________
• Patient/Volunteer Handling ________________________________
• Other molds, surface coils, etc. ______________________________
* A total of at least 20 hours on the system is required.
Documentation of Approval
_____________________________________________is approved to operate the
magnet system indicated below located at the WSU MR Research Facility in Harper University Hospital
Approval given by_______________________________________________.
Siemens 1.5T Sonata_____ Siemens/Bruker_____ Bruker 4.7T small bore______
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