EX 1 Flashcards by William Kerns

Which of the following holds the least threat in terms of biological threat to the patient?

Static magnetic field
Time-varying gradient field
Time-varying RF field

Time-varying gradient field

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When evaluating for concerns associated with the time-varying gradient field, which implant listed below is the most concerning?

Deep brain stimulator
Cardiac stent
Epicardial pacing leads
AAA repair

Deep brain stimulator

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What is the half wavelength for a 1.5 T unit?

60 cm
25 cm
5 cm
12 cm

25 cm

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Which of the following are true of 1.5 T MR units vs. 3.0 T? Select all that apply.

Implants that are safe at 3.0 T do not mean that they are safe at 1.5 T
Small metallic passive objects are safe at 3.0 T and not at 1.5 T
Ferrous objects show more attraction at 3.0 T vs 1.5 T
Heating in the pacemaker leads not connected to a generator is higher at 3.0 T than 1.5 T

implants that are safe at 3.0 T do not mean that they are safe at 1.5 T

Ferrous objects show more attraction at 3.0 T vs 1.5 T

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All the following are true of screening patients with a ferromagnetic detector except?

Any objects that are metal or electrically conductive will be detected by a ferromagnetic detector.
They provide a higher level of detecting MR threats when compared to a metal detector.
It will only detect objects that are attracted to a magnetic field.
A ferrous object must be moving through the ferromagnetic detector field in order to be detected.

Any objects that are metal or electrically conductive will be detected by a ferromagnetic detector.

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When advancing a patient into the bore, a patient with a pain pump complains of discomfort and like the device is moving within them. Once you stop moving the table, the discomfort stops as well. This is most likely caused by what?

Ohm’s law
Lorentz forces
Lenz forces

Lenz forces

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A patient is having an MR lumbar spine scan in normal mode. We know that the whole body SAR will not exceed which of the following?

1.0 W/kg
4.0 W/kg
2.0 W/kg
3.0 W/kg

2.0 W/kg

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What is the half wavelength for a 3.0 T unit?

12 cm
25 cm
5 cm
30 cm

12 cm

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5,000G is equal to _____ T.

0.5T
1T
2T
0.25T

0.5T

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Which of the following is true of the MR screening process according to the ACR Manual on MRI Safety? Select all that apply.

A written MR screening process is acceptable by a level 1 MR personnel as long as a level 2 MR personnel provides a verbal or interactive MR screening as well
A patient should be screened by at least one level 2 MR personnel verbally or interactively
Level 1 and 2 MR personnel need to have a more comprehensive MR screening process than used with patients
A patient should be MR screened twice

A patient should be MR screened twice

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What is the limit of the static magnetic field for patients <1 month old?

4T
8T
3T
2T

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Which of the following is true of tattoos? Select all that apply.

The strong static field can erase fresh tattoos
Skin can be twisted by the static magnetic field
Can rip out tattoos
Can cause a burn

Can cause a burn

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What is true of an MR screening sheet? Select all that apply.

All the answers must be marked “yes” or “no”
Anyone entering zone 2 must have a sheet filled out prior to entering it
A Level 1 and 2 personnel will have a different sheet filled out than a patient

All the answers must be marked “yes” or “no”

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Select the correct MR Unsafe symbol. Select all that apply.

black w/red
black w/black

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What is the FDA limit of the static magnetic field for patients >1 month old?

2T
4T
8T
10T

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An Essure coil is made of 316L stainless steel, platinum, iridium, and nickel-titanium alloy. Which of the following statements is true?

An Essure coil is ferrous and may demonstrate some torquing while in the static magnetic field.
An Essure coil is ferrous and will demonstrate some artifacts when imaging the implant.
An Essure coil is non-ferrous and may demonstrate some artifact when imaging the implant.

An Essure coil is non-ferrous and may demonstrate some artifact when imaging the implant.

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Which of the following is true when scanning pregnant patients?

Stay in normal mode
Scanning at 1.5 T suggested
Communicate with patient
All of the choices

Stay in normal mode
Scanning at 1.5 T suggested
Communicate with patient

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Peripheral nerve stimulations are caused by an electric field that exceeds ____.

0.4 V/m
4.3 V/m
2.2 V/m
1.1 V/m

2.2 V/m

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n order for the static magnetic field to be a true threat, an object could? Select all that apply.

Contain steel or iron
Contain 316L stainless steel
Be electrically conductive
Enter the MR environment

Contain steel or iron

Enter the MR environment

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The ICNIRP states that moving through a field strength above ______ may be high enough to produce vertigo and other sensory perceptions like nausea or magnetophosphenes.

1.0 T
4.0 T
2.0 T
3.0 T

2.0 T

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The ICNIRP sets an occupational dose of ____ to the head and torso.

Spatial peak magnetic flux density of 6 T
Spatial peak magnetic flux density of 2 T
Spatial peak magnetic flux density of 1 T
Spatial peak magnetic flux density of 4 T

Spatial peak magnetic flux density of 2 T

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The quench vent outside the MR facility is inspected by who?

MR Technologist
Manufacturer engineer
MRMD
Facility engineer

Facility engineer

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Which of the following is typically labeled non-MR personnel? Select all that apply.

Local firefighter
Family of patient
Referring physicians
Security
Patient transport

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A proximity burn occurs when?

When a electrical conductive material is placed on our patient.
When a patient’s skin forms a conductive loop.
When an ECG wire forms a loop.
A patient’s skin is in contact with the gantry.

A patient’s skin is in contact with the gantry.

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All the zones need to be represented with signage except? Zone 4 Zone 2 Zone 1 Zone 3 All need to be represented, but zone 1 may be optional depending on the auditing body

All need to be represented, but zone 1 may be optional depending on the auditing body

PNS occurs in our patient due to which of the following processes? Faraday's law Ohm's law Lenz Law Lorentz forces

Faraday's law

A patient is exposured to 99dBA and has earplugs with an NRR of 29. What is the level of noise the patient will experience? 88dBA 70dBA 85dBA 90dBA

88dBA (29-7)/2=11. 99-11 = 88dBA

A patient had an MRI a month ago and had suffered a moderate allergic reaction. The patient is in need of another MR with contrast tomorrow. How can we reduce the risk of this… Give the patient Xanax prior to the exam Have a code blue team on standby in zone IV for the duration of the exam Give a half dose of GBCM Give steroids to the patient 6 hours before their exam

Give steroids to the patient 6 hours before their exam

A large ferrous object is stuck against the MRI unit and no one is in harm’s way. What should you do? Pull the object off of the unit yourself All of the choices There is no need to report this event since it did not hurt anyone Contact trained personnel to remove the object

Contact trained personnel to remove the object

This individual manages day-to-day MR safety issues, enforces policies, and provides MR safety knowledge. MRMD MRSO MRSE

MRSO

What makes the time-varying gradient field (TVGF) different than the time-varying RF field (TVRF)? The TVGF will produce resonance in the patient. The TVGF uses a faster changing magnetic field than the TVRF. The TVGF uses a slower changing magnetic field than the TVRF. The TVGF will induce more heating in the patient than the TVRF.

The TVGF uses a slower changing magnetic field than the TVRF.

Gadolinium contrast has been found in the body in what form? Select all that apply. Water soluble Non-water soluble Free gadolinium is not bound to anything

Water soluble Non-water soluble

Which of the following are true of the copper T or copper 7 IUD? Select all that apply. Can produce significant heating Can become dislodged Contains thin coiled copper wires Produce large artifacts

Contains thin coiled copper wires

If a cryogen comes in contact with skin, what will happen? Explode Combust Frostbite/necrosis Nothing, in its gas form

Frostbite/necrosis

According to the IEC, what is the limit for the static magnetic field for clinical MRI? 200 mT 8 T 400 mT 4 T

8 T

A patient is complaining of discomfort from high SAR during a fast spin echo. What can be done to make them more comfortable? Increase the flip angle Increase the receiving bandwidth Decrease the TR Decrease the echo train length

Decrease the echo train length

Where would we expect to see the maximum peripheral nerve stimulation in our patient who is having an MR lumbar spine exam performed head first? Lumbar spine Thighs Feet Abdomen

Thighs

Which of the following IUD contain ferrous material? Select all that apply. Mirena IUD Copper T Copper 7 None of the choices

None of the choices

Which of the following statements are true of gadolinium contrast? Select all that apply. It is hypothesized that gadolinium retention occurs due to it following pathways that other metals do, such as iron and calcium. Gadolinium is not linked to NSF. Gadolinium retention has been linked to gadolinium-associated plaques. Cases of NSF have been increasing over the last 5 years

It is hypothesized that gadolinium retention occurs due to it following pathways that other metals do, such as iron and calcium.

Which of the following agents are the most stable? All are equally stable Macrocyclic Non-ionic linear Ionic linear

Macrocyclic

Why is it recommended to tape or wrap gauze around jewelry? To make sure translational force does not occur To reduce the magnetic susceptibility To reduce contact with the skin To make sure rotational force does not occur

To reduce contact with the skin

According to the ASTM F2503 document, the MR environment refers to what? Anything within the 5 Gauss line An area that contains the Faraday shield and the 5 Gauss line Zone 3 and Zone 4 Zone 4

An area that contains the Faraday shield and the 5 Gauss line

Which of the following issues are most likely to occur when exposing a neurostimulator to RF and cause the most immediate threat to our patient? Rotational force Magnophosphenes Translational force Burns

Burns

The quench vent in the MR room should be inspected by who? MRMD MR technologist Manufacturer engineers Facility engineers

Manufacturer engineers

Which of the following is true of gadolinium retention? Select all that apply. It is a result of free gadolinium in the patient It is seen in only renal compromised patients Every linear agent produces the same amount of retention in the brain. It is seen in bone and brain tissue

It is a result of free gadolinium in the patient

What can be done to reduce pressure in an MR scan room during a quench with a defective room vent and a door that opens into the scan room? A patient is in the room. Break the window to zone IV Open the door to zone IV Drill a hole into the wall to zone IV Wait 20 minutes for the pressure to dissipate

Break the window to zone IV

A patient is complaining of discomfort during a single shot fast spin echo sequence. What can be done to make them more comfortable? Increase the phase encoding resolution Decrease the TR Use parallel imaging Scan only in the axial plane

Use parallel imaging

What are ways to reduce the negative effects associated with the time-varying gradient field? Select all that apply. Increase the number of RF pulses Increase the field strength Decrease the acquisition speed (switching magnetic fields) Decrease the strength of the gradient field magnetic slope (gradient amplitude)

Decrease the acquisition speed (switching magnetic fields) Decrease the strength of the gradient field magnetic slope (gradient amplitude)

Which of the following implants hold the most thermal risk to a patient? Gallbladder clip Abandon pacemaker lead Pacemaker lead attached to a generator Bone screw

Abandon pacemaker lead

Which of the following is most likely experienced by the patient being exposed to a fast time-varying gradient field? Translational force Lenz’s effect Tingling Burn

Tingling

When handling a code in the MR environment, which of the following are NOT best practices according to the ACR? A patient should be completely stable prior to removing a patient from zone 4 It is suggested that a patient be brought to zone 2 but can be in zone 3 if necessary to resuscitate the patient All the choices should not be done The patient must be removed from zone 4 before calling a code

A patient should be completely stable prior to removing a patient from zone 4

Select all that will produce/influence magnetophosphenes from the static magnetic field. Rate of motion through a magnetic field Patient sex Weight of patient Strength of field strength

Rate of motion through a magnetic field Strength of field strength

What type of contrast is Dotarem? Non ionic, macrocylic Ionic, non ionic Ionic, macrocylic Linear, macrocylic

Ionic, macrocylic

Which of the following are considered long-term effects of gadolinium contrast media? Select all that apply. Anaphylaxis Emesis Nephrogenic systemic fibrosis Gadolinium associated plaques

Nephrogenic systemic fibrosis Gadolinium associated plaques

The change in pressure in the MRI scan room can do what? Cause condensation to accumulate on the patient Detach the MR table Increase the static magnetic field Pressure locking of access to zone IV

Pressure locking of access to zone IV

Which of the following is used to calculate renal function? Select all that apply. Platelet count Creatinine Patient white blood cell count D-dimer

Creatinine

n order for the time-varying RF field to be a threat, an object could? Select all that apply. Be electrically conductive Non-ferrous and non-metallic Form a conductive loop Be >2cm in size

Be electrically conductive Form a conductive loop Be >2cm in size

Which of the following agents yields the best chance for transmetalation to occur? Linear ionic Macrocyclic ionic Linear non-ionic Macrocyclic non-ionic

Linear non-ionic

During a malfunctioned quench what would we expect to see? Select all that apply. Increase in temperature Decrease in room pressure Changing magnetic field Explosion risk

Changing magnetic field Explosion risk

Which of the following has theoretically been deemed a threat to a patient with a heart valve containing non-magnetic metallic disks or leaflets at ultra-high field strengths? Antenna effect Translational force Rotational force Lenz’s effect

Lenz’s effect

Transient dyspnea: Is seen in repeat contrast reactions Is associated with chronic obstructive pulmonary disease and noted after the administration of any GBCM. Describes the manifestation of transient severe respiratory motion-related artifact in the arterial phase after the administration of gadoxetate disodium. Is an acute reaction after the administration of gadoxetate disodium and requires immediate intervention

Describes the manifestation of transient severe respiratory motion-related artifact in the arterial phase after the administration of gadoxetate disodium.

A patient has an external fixation device that is labeled as MR conditional. All the conditions are met and you scan the patient. The patient says that the external fixation device starts vibrating. This is caused by which of the following? All of the choices Time-varying RF field Static magnetic field Time-varying gradient field

Time-varying gradient field

A manufacturer’s instructions define that an implant can be scanned at 2 W/kg for 15 min. What does this mean? The patient can be scanned only in normal mode for a total exam time greater than 15 min. Patients can be scanned in first-level as long as the total exam time is less than 7.5 min. The patient can be scanned in first-level controlled mode as long as the individual sequence does not exceed 15 min. The patient can be scanned in normal mode as long as the individual sequence does not exceed 15 min.

The patient can be scanned in normal mode as long as the individual sequence does not exceed 15 min.

Which of the following is true of gadolinium-associated plaques? Select all that apply. This is a common occurrence in MRI It is the same thing as NSF It occurs when gadolinium is ingested It is not related to renal compromised patients

It is not related to renal compromised patients

When evaluating for concerns associated with the time-varying gradient field, which implant listed below is of most concern? Hip replacement All the choices MR Conditional insulin pump Cardiac pacemaker

Cardiac pacemaker

Anthropogenic effects of gadolinium would most likely be seen where? Cities with large healthcare facilities Rural areas Towns with many rivers and lakes

Cities with large healthcare facilities

A patient is having an MR brain scan in first-level controlled mode with a receive-only coil. We know that the whole body SAR for a head will not exceed which of the following? 8 W/kg 2.0 W/kg 4.0 W/kg 3.2 W/kg

3.2 W/kg

All the following except what makes a patient more prone to an allergic reaction to gadolinium? Allergy to CT contrast Seasonal Allergies High Blood Pressure Prior Gadolinium Reaction

High Blood Pressure

Guidewires can produce heating in the patient due to which of the following? Reflective burn Proximity burn Antenna effect A loop of conductive tissue

Antenna effect

What needs to be in site when complying with the line of sight rule defined in the ACR Manual on MRI Safety? Select all that apply. Patient Door to Zone 4 Console Door to Zone 3

Patient Door to Zone 4 Console

A patient is complaining of severe discomfort and tingling during a GRASS sequence in normal control mode. What can be done to make the patient more comfortable? Increase the echo train length Scan in first level control mode Increase the flip angle Use a spin echo sequence

Use a spin echo sequence

As we approach the MRI unit, which of the following occur without any time-varying magnetic fields activated? Select all that apply. Translational force increases Rotational force increases Non-ferrous objects are attracted to the MR unit Patients may experience burns

Translational force increases Rotational force increases Non-ferrous objects are attracted to the MR unit

An MR Conditional implant or device should minimally address which of the following per the ASTM guidelines. Select all that apply. Patient position Static magnetic field Radiofrequency fields Switched gradient magnetic fields

Static magnetic field Radiofrequency fields Switched gradient magnetic fields

What type of gadolinium contrast has been shown to cause falsely low serum calcium laboratory values? Linear non-ionic Linear ionic There is no correlation Macrocyclic

Linear non-ionic

A patient is having an MR with IV-administered GBCM. This patient has sickle cell disease. Which of the following is true? The risk of adverse effects to the patient is minimal and there is no reason to withhold administration. Contrast media should not be given. A GFR should be obtained prior to injection. Patients should receive a hydration protocol and be pre-medicated.

The risk of adverse effects to the patient is minimal and there is no reason to withhold administration.

Which of the following is true of gadolinium and breastfeeding mothers? Select all that apply. It is thought that gadolinium contrast may alter the taste of breast milk Available data suggest that breast-feeding should be pumped and discarded for 24 hours after the intravenous dose 20% of the intravascular dose would be excreted into the breast milk within the first 24 hours Gadolinium is found in breast milk in a stable and chelated form

It is thought that gadolinium contrast may alter the taste of breast milk Gadolinium is found in breast milk in a stable and chelated form

The magnetohydrodynamic effect will influence what? R wave S wave P wave T wave

T wave

Which of the following are correct when using a metal detector to screening a patient for MR threats? They are one of the most effective means of identifying risk in MR. They are a must in ensuring the safety of our patients and are recommended by the ACR Manual on MRI Safety They will only detect ferrous objects. They can not determine what is ferrous or not.

They can not determine what is ferrous or not.

RF-induced heating in a patient or implant will depend on which of the following? Select all that apply. Department policies Position of the implant or patient MR RF coil used Overall MR field strength

Position of the implant or patient MR RF coil used Overall MR field strength

Select the correct MR Conditional symbol. Select all that apply.

yellow/black white/black

Which of the following orthopedic implants would we expect to demonstrate the largest chance of a burn during an MR exam? Lumbar Fusion AAA repair Hip Replacement External Fixation System

External Fixation System

Which of the following locations are found in the MR environment? Select all that apply. C B D A

Which of the following issues could occur with an insulin/pain pump? Select all that apply. Damage to the pump Infusing a bolus of medication Heating in leads

Damage to the pump Infusing a bolus of medication

Select the correct MR Safe symbol. Select all that apply.

white/green green/white white/black black/white

Which of the following are considered short-term (non-allergic or allergic reactions) effects of gadolinium contrast media? Select all that apply. Swelling Hives Emesis Nephrogenic systemic fibrosis

Swelling Hives Emesis

Which of the following will produce the largest artifact in the MR environment? Nickel alloy AAA repair Cobalt cardiac stent Titanium clip Steel L-spine cage

Steel L-spine cage

In order for cryogen to not harm a patient, what needs to happen? The cryogen must be filtered to make it safe to breath The cryogen should be vented underground The cryogen needs to be warmed to room temperature The cryogen needs to be vented outside

The cryogen needs to be vented outside

A patient is complaining of severe discomfort during a DWI sequence. What can be done to make the patient more comfortable? Shortening the TR Increasing image matrix Perform a fast spin echo Perform an SSFP sequence instead

Perform a fast spin echo

Which of the following reactions are most common when administering MR contrast? Gadolinium associated plaques Allergic reactions NSF Physiologic reactions

Physiologic reactions

An emergent quench can take approximately how long? 2-4 minutes 30 seconds -1 minute 10 seconds 5-15 minutes

30 seconds -1 minute

Which of the following increases the odds that a patient will develop NSF after injection of gadolinium contrast? Select all the apply. Hypertension Renal disease Patients over 60 years older Migraines

Hypertension Renal disease Patients over 60 years older

What is the best way to prevent NSF? Select the single best answer. Don’t give gadolinium contrast to patients who are in renal failure NSF cannot be prevented Perform dialysis on the patient prior to the gadolinium contrast injection Hydrate patient prior to gadolinium injection

Don’t give gadolinium contrast to patients who are in renal failure

An MR fetus study is being performed. What field strength should be used to scan this patient according to the FDA? < 4.0 T Only 0.5 T >3.0 T >8.0 T

< 4.0 T

Which of the following is considered an allergic reaction to gadolinium contrast media? Select all that apply. Swelling Elevated eGFR Headache Hives

Swelling Hives

Which of the following are sensations that occur from the time-varying gradient field? Pain Tingling All of the choices Twitching

Pain Tingling Twitching

A sequence is run with peak unweighted sound pressure of 120dB. Is this within IEC regulation? Yes No

Yes peak is 140

Which of the following reasons why a tissue expander may be contraindicated for MRI? These implants may contain magnetic components that can be attracted to the MR unit. These implants contain large conductive metals that can heat up during acquisition. All of the choices These implants can produce uncomfortable peripheral nerve stimulation.

These implants may contain magnetic components that can be attracted to the MR unit.

The ICNIRP sets an occupational dose of ____ to the limbs. Up to 10 T Up to 2 T Up to 4 T Up to 8 T

Up to 8 T

Which of the following images demonstrates an MR unit that is shielded? B A

Which of the following will influence translational force? Select all that apply. Strength of the magnetic field strength Magnetic susceptibility Mass of the object Spatial gradient magnetic field

Strength of the magnetic field strength Magnetic susceptibility Mass of the object Spatial gradient magnetic field