MRI Safety: Understanding Patient Limits, Unsafe Devices, and Magnetic Fields, Exams of Nursing

Download MRI Safety: Understanding Patient Limits, Unsafe Devices, and Magnetic Fields and more Exams Nursing in PDF only on Docsity! 1 | P a g e MRSO MOCK EXAM 2024 WITH ACTUAL CORRECT QUESTIONS AND VERIFIED DETAILED RATIONALES ANSWERS BY EXPERTS |FREQUENTLY TESTED QUESTIONS AND SOLUTIONS |ALREADY GRADED A+ |NEWEST |LATEST UPDATE | GUARANTEED PASS The transmission of radiofrequency waves will cause what? A. Peripheral nerve stimulation B. Patient heating C. Magnetohydrodynamic effect D. Vertigo B. Patient heating Unsafe electrical devices in patients should be restricted from which of the following? A. Entering Zone 2 B. Entering Zone 1 C. Crossing the 5-gauss line D. Crossing the 10-gauss line C. Crossing the 5-gauss line Which of the following is used to measure patient heating? A. Patient heating ratio B. Specific energy resonance C. Set absorption ratio D. Specific absorption rate D. Specific Absorption Rate What type of MRI unit uses many bricks of magnets to produce a strong static field? 2 | P a g e A. All of choices B. Resistive magnet C. Permanent Magnet D. Superconducting magnet C. Permanent Magnet Which of the following are units of measurements for static magnetic fields? A. Decibels B. Tesla C. Gauss D. Tesla and Gauss D. Tesla and Gauss When does resonance occur? A. When the patient is placed in isocenter and only experiences the static magnetic field B. When the radiofrequencies transmitted match the precessional speed of hydrogen. C. When the radiofrequencies are different than the precessional speed of hydrogen. D. When the radiofrequency is transmitted at 42.6 MHz B. When the radiofrequencies transmitted match the precessional speed of hydrogen. An object that produces a weak repulsive force in presence of a strong magnetic field is called what? A. Diamagnetic B. Paramagnetic C. Superparamagnetic D. Ferromagnetic A. Diamagnetic What does the image of MR with a red circle and slash through it represent? A. MR Unsafe B. MR Conditional C. MR Safe D. MR Compatible A. MR Unsafe Where is Cryogen found? A. In the MR unit B. In zone 3 C. In the equipment room D. In the quench vent 5 | P a g e A. The rise time B. Spatial gradient C. Maximum gradient peak D. The slew rate C. Maximum gradient peak As blood flows through a vessel, currents can be induced. The degree of this is called? A. Magnetophosphenes B. Fringe field C. Translational forces D. Flow potential D. Flow potential A patient is undergoing an MRI exam and is given an ice pack to reduce heat. Which of these methods is the patient using to regulate their increased heating? A. Radiation B. Evaporation C. Convection D. Conduction D. Conduction What GFR level indicates normal kidney function? A. 0ml/min/1.73m2 B. 60-89 mL/min/1.73m2 C. 30-45 mL/min/1.73m2 D. 45-60 mL/min/1.73m2 B. 60-89 mL/min/1.73m2 A patient will change into a gown in this location? A. Zone 1 B. Zone IV C. Zone 3 D. Zone 2 D. Zone 2 Which of the following describes an electrical current produced in a wire when subjected to an alternating magnetic field? A. Ohms Law B. Faradays law of induction 6 | P a g e C. Lorenz force D. Fourier Transformation B. Faradays Law of induction What is the risk associated with rotational force? A. Peripheral nerve stimulation B. Missile effect C. Antenna effect D. Torque on an implant D. Torque Implant Time-varying gradient magnetic fields are measured in which of the following? A. dB/dx B. Tesla C. dB/dt D. W/kg C. dB/dt An object that retains a magnetic field as it is removed from a strong magnetic field is called what? A. Diamagnetic B. Ferromagnetic C. Superparamagnetic D. Paramagnetic B. Ferromagnetic Why is magnetic shielding used on an MR unit? A. To limit fringe field B. To maintain field homogeneity C. To reduce the e-fields D. To reduce heating A. To limit fringe field The control room is commonly found where? A. Zone 2 B. Zone 4 C. Zone 3 D. Zone 1 C. Zone 3 7 | P a g e A gadolinium ion is attracted to a molecule called a/an? A. Ligand B. String C. Chain D. Ion A. Ligand Which of the following describes when a non-ferrous, electrically conductive object is repulsed by a static magnetic field? A. Fourier Transfomation B. Larmor equation C. Lenz force D. Ohms law C. Lenz force What is the purpose of resonance? A. Resonance is not used in MRI B. To tilt the nuclei of interest away from B0 C. To slow down the precessional frequency or nuclei D. To align nuclei with B0 B. To tilt nuclei of interest away from B0 Induction of electrical current in our patient from changing magnetic fields can be described by which of the following? A. Ohms Law B. Faradays Law C. Fourier equation D. Larmor equation B. Faradays law The near field effects of the RF energy can cause what kind of issue? A. Proximity Burning B. Resonant burning C. Reflective burning D. Missile effect A. Proximity burning Which of the following is true of a crime in legal cases? 10 | P a g e What type of MRI unit uses a cryogen? A. Permanent B. All of the choices C. Superconducting D. Resistive C. Superconducting Which of the following describes the total dose of energy that a tissue receives during an entire exam? A. Overall concentration dose B. Specific Energy dose C. Total voltage absorbed D. Specific Absorption Rate B. Specific Energy dose Which of the following is an ASTM MR labeling option for an object in the MR environment? A. MR compatible B. MR safe C. MR conditional D. MR unsafe B. MR safe C. MR Conditional D. MR unsafe An area that is outside of any MR area and is accessible to the general public is called what? A. Zone 2 B. Zone 4 C. Zone 1 D. Zone 3 C. Zone 1 The speed that the gradient coils can turn on and off is called what? A. Maximum gradient peak B. Spatial gradient C. The slew rate D. The rise time C. The slew rate The FDA limits SAR in the head to what? 11 | P a g e A. 3.2 W/kg for 10 min B. 4 W/kg for 15 min C. 8 W/kg for 20 min D. 10 W/kg for 15 min A. 3.2 W/kg for 10 min The B1 field is found where? A. 180 degrees to the B0 B. In the same direction as the B0 C. Varies from scan to scan D. 90 degrees to the B0 D. 90 degrees to the B0 Emesis after a contrast reaction is considered what? A. An allergic reaction to contrast media B. A non- allergic reaction to contrast media C. None of the choices D. Anaphylaxis B. A non- allergic reaction to contrast media Which of the following require the minimal MR safety training? A. Level 2 MR personnel B. Level 1 MR personnel C. The patient D. Non MR personnel B. Level 1 MR personnel Anthrogenic gadolinium can be described as what? A. The influence of gadolinium on patients with renal insufficiency B. When the accumulation of gadolinium occurs in the body C. When gadolinium is found in the water supply D. When the retention of gadolinium in specific tissues is present C. When gadolinium is found in the water supply What is a quench? A. Not used in MRI B. Rebooting the MR unit C. Moving a patient out of a scanner slowly D. The release of the cryogen from an MR unit 12 | P a g e D. The release of the cryogen from an MR unit Which of the following is used to determine renal function? A. D- dimer B. GFR C. Both GFR and D- dimer D. Blood platelet B. GFR Passive shield is performed how? A. A coil of wire in the MR unit has a current running through it which produces a magnetic field opposing the B0 B. Bricks of permanent magnets are stacked around the MR unit to contain the fringe field C. Nothing is used with passive shielding D. A Magnetically conductive material surrounds the MR unit and this shapes and contains the magnetic field D. A Magnetically conductive material surrounds the MR An object that produces a weak attractive force in the presence of a strong magnetic field is called what? A. Paramagnetic B. Superparamagnetic C. Ferromagnetic D. Diamagnetic A. Paramagnetic What is the risks associated with translational force? A. Proximity Heating B. Missile effect C. Peripheral nerve stimulation D. Antenna effect B. Missile effect Which of the following is measured in milliseconds? A. The rise time B. The slew rate C. Maximum gradient peak D. Spatial gradient A. Rise time 15 | P a g e What gradient coil will produce coronal images? A. Z gradient B. All of the choices C. X gradient D. Y gradient D. Y Gradient Gadolinium contrast will appear how on a T1 weighted image? A. Dark B. Not be seen C. Gray D. Bright D. Bright Cryogen can escape from the MR room through what? A. Cryogen path B. Control room C. Quench vent D. Door C. Quench vent What pulse sequence will produce the most patient heating? A. Inverse recovery sequence B. Single shot fast spin echo C. Conventional spin echo D. Gradient Echo B. Single shot fast spin echo During acquisition, it is noticed that the T wave of the cardiac cycle is elevated. What is this artifact called? A. Magnetohydrodynamic Effect B. Excitation C. Teratogenesis D. Magnetophosphenes A. Magnetohyrdodynamic Effect When can heating occur in a wire? A. Only in ferrous object 16 | P a g e B. When the transmitted wavelength is half of the B0 field strength or is a multiple of the length of that C. When objects get smaller D. In small round metal objects B. When the transmitted wavelength is half of the B0 field strength or is a multiple of the length of that What unit of measure is used for SAR? A. A/1b B. dB/dx C. dB/dt D. W/kg D. W/kg The IEC 60601-2-33 whole body normal operating mode is ________________ the energy requirements limited in the first level controlled operating mode. A. Triple B. Double C. Half D. Not comparable to C. Half Which of the following are recommended by the ACR guidance in MR Safety 2013 in proper scanning of a patient? A. Metal Detector B. Ferromagnetic detection system C. Written screening sheet D. Patient Gown B. Ferromagnetic detection system C. Written screening sheet D. Patient Gown Using a headset and ear plugs will reduce the noise by how much? A. By the NRR of headset B. By the NRR of the headset and NRR of earplugs C. 50 dB D. By the NRR of the headset and the NRR of earplug divided by 2 B. By the NRR of the headset and NRR of earplugs What is the FDA SAR limit for the whole body in first level controlled operating mode? A. 7 W/kg for 6 min 17 | P a g e B. 4 W/kg for 6min C. 3 W/kg for 6 min D. 8 W/kg for 6 min B. 4 W/kg for 6 min Which of the following is true of Zone IV? Select all that apply. A. Should be noted with signage B. No unsafe implants may cross the 5-guass unless implant is researched and analyzed for risk C. Contain metal detectors for implant identification D. This area should be monitored by a level 2 MR personnel A. Should be noted with signage B. No unsafe implants may cross the 5-guass unless implant is researched and analyzed for risk D. This area should be monitored by a level 2 MR personnel Pain at the injection site when gadolinium contrast is administered is considered what? A. None of these choices B. Anaphylaxis C. An allergic reaction D. A non-allergic reaction D. Non allergic reaction How long does it take to excrete gadolinium contrast from a patient with normal kidney function? A. 24 hours B. 48 hours C. 4 hours D. 9 hours A. 24 Hours How many gauss are in one Tesla? A. 10 B. 10,000 C. 100 D. 1,000 B. 10,000 Gadolinium contains what kind of magnetism? A. Super paramagnetic B. Ferromagnetic 20 | P a g e A headache after contrast injection is considered what? A. None of the choices B. Anaphylaxis C. Allergic reaction D. Non allergic reaction D. Non allergic reaction The invisible fields that flow from the north pole to south pole of a magnet are called? A. Voltages B. Radiant fields C. Electrical current D. Magnetic flux lines D. Magnetic Flux line What type of gadolinium contrast has been shown to cause falsely low serum calcium laboratory values? There is no correlation Macrocyclic Linear ionic Linear non-ionic Linear non-ionic What is the limit of the static magnetic field for patients <1 month old? 2T 8T 4T 3T 4T Which of the following implants hold the most thermal risk to a patient? Bone screw Pacemaker lead attached to a generator Abandon pacemaker lead Gallbladder clip Abandon pacemaker lead PNS occurs in our patient due to which of the following processes? Lenz Law Faraday's law 21 | P a g e Lorentz forces Ohm's law QUESTION ERROR/CONCERN Faraday's law 5,000G is equal to _____ T. 2T 0.25T 1T 0.5T 0.5T Which of the following is true of tattoos? Select all that apply. Skin can be twisted by the static magnetic field The strong static field can erase fresh tattoos Can cause a burn Can rip out tattoos Can cause a burn 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. Door to Zone 3 Console Patient Door to Zone 4 Console Patient Door to Zone 4 Anthropogenic effects of gadolinium would most likely be seen where? Rural areas Towns with many rivers and lakes Cities with large healthcare facilities Cities with large healthcare facilities Which of the following are correct when using a metal detector to screening a patient for MR threats? They can not determine what is ferrous or not. They will only detect ferrous objects. They are one of the most effective means of identifying risk in MR. 22 | P a g e They are a must in ensuring the safety of our patients and are recommended by the ACR Manual on MRI Safety They can not determine what is ferrous or not. 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 What is the FDA limit of the static magnetic field for patients >1 month old? 10T 2T 4T 8T 8T 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. A proximity burn occurs when? A patient's skin is in contact with the gantry. When an ECG wire forms a loop. When a patient's skin forms a conductive loop. When a electrical conductive material is placed on our patient. A patient's skin is in contact with the gantry. According to the IEC, what is the limit for the static magnetic field for clinical MRI? 400 mT 200 mT 8 T 4 T 8 T 25 | P a g e 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? 4.0 W/kg 1.0 W/kg 2.0 W/kg 3.0 W/kg 2.0 W/kg 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 All the zones need to be represented with signage except? Zone 2 Zone 1 Zone 3 All need to be represented, but zone 1 may be optional depending on the auditing body Zone 4 All need to be represented, but zone 1 may be optional depending on the auditing body When evaluating for concerns associated with the time-varying gradient field, which implant listed below is of most concern? All the choices Hip replacement Cardiac pacemaker MR Conditional insulin pump Cardiac pacemaker Which of the following orthopedic implants would we expect to demonstrate the largest chance of a burn during an MR exam? AAA repair External Fixation System Hip Replacement Lumbar Fusion 26 | P a g e External Fixation System Peripheral nerve stimulations are caused by an electric field that exceeds ____. 0.4 V/m 2.2 V/m 1.1 V/m 4.3 V/m 2.2 V/m Which of the following is true of gadolinium retention? Select all that apply. Every linear agent produces the same amount of retention in the brain. It is seen in bone and brain tissue It is seen in only renal compromised patients It is a result of free gadolinium in the patient It is seen in bone and brain tissue 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? Abdomen Feet Thighs Lumbar spine Thighs What is the half wavelength for a 3.0 T unit? 5 cm 25 cm 30 cm 12 cm 12 cm The change in pressure in the MRI scan room can do what? Pressure locking of access to zone IV Increase the static magnetic field Cause condensation to accumulate on the patient Detach the MR table Pressure locking of access to zone IV 27 | P a g e 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 in normal mode as long as the individual sequence does not exceed 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 only in normal mode for a total exam time greater than 15 min. The patient can be scanned in normal mode as long as the individual sequence does not exceed 15 min. In order for cryogen to not harm a patient, what needs to happen? The cryogen needs to be vented outside The cryogen needs to be warmed to room temperature The cryogen must be filtered to make it safe to breath The cryogen should be vented underground The cryogen needs to be vented outside Which of the following reactions are most common when administering MR contrast? Physiologic reactions Allergic reactions NSF Gadolinium associated plaques Physiologic reactions Which of the following agents are the most stable? Macrocyclic Ionic linear All are equally stable Non-ionic linear Macrocyclic In 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 30 | P a g e Hypertension Patients over 60 years older Renal disease What type of contrast is Dotarem? Ionic, macrocylic Non ionic, macrocylic Ionic, non ionic Linear, macrocylic Ionic, macrocylic Gadolinium contrast has been found in the body in what form? Select all that apply. Free gadolinium is not bound to anything Water soluble Non-water soluble Water soluble Non-water soluble Which of the following are considered long-term effects of gadolinium contrast media? Select all that apply. Nephrogenic systemic fibrosis Anaphylaxis Gadolinium associated plaques Emesis Nephrogenic systemic fibrosis Gadolinium associated plaques Which of the following will produce the largest artifact in the MR environment? Cobalt cardiac stent Titanium clip Steel L-spine cage Nickel alloy AAA repair Steel L-spine cage RF-induced heating in a patient or implant will depend on which of the following? Select all that apply. Overall MR field strength MR RF coil used Department policies Position of the implant or patient 31 | P a g e Overall MR field strength MR RF coil used Position of the implant or patient Which of the following are considered short-term (non-allergic or allergic reactions) effects of gadolinium contrast media? Select all that apply. Nephrogenic systemic fibrosis Hives Swelling Emesis Hives Swelling Emesis Which of the following statements are true of gadolinium contrast? Select all that apply. Gadolinium is not linked to NSF. It is hypothesized that gadolinium retention occurs due to it following pathways that other metals do, such as iron and calcium. 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 reasons why a tissue expander may be contraindicated for MRI? All of the choices These implants can produce uncomfortable peripheral nerve stimulation. These implants contain large conductive metals that can heat up during acquisition. These implants may contain magnetic components that can be attracted to the MR unit. These implants may contain magnetic components that can be attracted to the MR unit. Which of the following is considered an allergic reaction to gadolinium contrast media? Select all that apply. Hives Headache Elevated eGFR Swelling 32 | P a g e Swelling Hives The quench vent in the MR room should be inspected by who? MRMD MR technologist Manufacturer engineers Facility engineers Manufacturer engineers 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 As we approach the MRI unit, which of the following occur without any time-varying magnetic fields activated? Select all that apply. Patients may experience burns Translational force increases Rotational force increases Non-ferrous objects are attracted to the MR unit Translational force increases Rotational force increases Which of the following are true of the copper T or copper 7 IUD? Select all that apply. Can become dislodged Can produce significant heating Contains thin coiled copper wires Produce large artifacts Contains thin coiled copper wires A sequence is run with peak unweighted sound pressure of 120dB. Is this within IEC regulation? No Yes 35 | P a g e 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 It is thought that gadolinium contrast may alter the taste of breast milk 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 agents yields the best chance for transmetalation to occur? Linear ionic Linear non-ionic Macrocyclic ionic Macrocyclic non-ionic Linear non-ionic A patient is complaining of severe discomfort during a DWI sequence. What can be done to make the patient more comfortable? Increasing image matrix Perform an SSFP sequence instead Perform a fast spin echo Shortening the TR Perform a fast spin echo Guidewires can produce heating in the patient due to which of the following? Reflective burn A loop of conductive tissue Antenna effect Proximity burn Antenna effect The ICNIRP sets an occupational dose of ____ to the limbs. Up to 4 T Up to 8 T Up to 10 T Up to 2 T 36 | P a g e Up to 8 T A patient is having an MR with IV-administered GBCM. This patient has sickle cell disease. Which of the following is true? A GFR should be obtained prior to injection. Contrast media should not be given. The risk of adverse effects to the patient is minimal and there is no reason to withhold administration. 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 typically labeled non-MR personnel? Select all that apply. Security Family of patient Local firefighter Referring physicians Patient transport Security Family of patient Local firefighter Referring physicians Patient transport An emergent quench can take approximately how long? 2-4 minutes 30 seconds -1 minute 10 seconds 5-15 minutes 30 seconds -1 minute 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 4 Zone 3 and Zone 4 An area that contains the Faraday shield and the 5 Gauss line Which of the following holds the least threat in terms of biological threat to the patient? 37 | P a g e Time-varying gradient field Time-varying RF field Static magnetic field Time-varying gradient field 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 Rotational force Translational force Lenz's effect Lenz's effect Which of the following are sensations that occur from the time-varying gradient field? Twitching Tingling Pain All of the choices All of the choices Which of the following is true when scanning pregnant patients? Stay in normal mode All of the choices Scanning at 1.5 T suggested Communicate with patient All of the choices Which of the following are true of 1.5 T MR units vs. 3.0 T? Select all that apply. Ferrous objects show more attraction at 3.0 T vs 1.5 T Implants that are safe at 3.0 T do not mean that they are safe at 1.5 T Heating in the pacemaker leads not connected to a generator is higher at 3.0 T than 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 Implants that are safe at 3.0 T do not mean that they are safe at 1.5 T A large ferrous object is stuck against the MRI unit and no one is in harm's way. What should you do?