Facilities and Cryogens Flashcards
The MR operator should have a direct line of sight of which of the following at all times while sitting at the operator’s console:
The patient call button and the entrance to zone 4
The patient paperwork and ECG
The patient and the entrance to zone 4
Waiting patients and patient on the table
The patient and the entrance to zone 4
During a quench, a cloud or fog can be seen in the scan room. What causes this fog?
Helium gas looks cloudy
Frozen water vapor in room air
An interaction between helium and the ceiling
Frozen water vapor in room air
An appropriate placement of a ferromagnetic detection system would be in Zone III, approaching Zone IV. True or False?
True
False
True
Which option listed is NOT a possible risk associated with a quench?
Asphyxia
Pressure entrapment
Hypothermia
Fire
Electrocution
Electrocution
The cryogen of choice is usually _________, which cools the windings to 4.2 degrees Kelvin in order to maintain superconductivity within solenoid electromagnets.
Liquid nitrogen
Liquid hydrogen
Liquid helium
Liquid gadolinium
Water
Liquid helium
MRI systems limit or “throttle” maximum allowable SAR to lower maximum allowable value when ambient room temperature exceeds 24°C (75°F). True or False?
True
False
True
Ice/frost on the cryostat is normal. True or False?
True
False
False
Helium is colorless, odorless, and heavier than air. True or False?
True
False
False
What is NOT true in regards to a quench?
There may be some cryogens left in the cryostat after a quench.
There will be an instant, temporary increase in the magnetic field until it begins to gradually decline because of a rise in resistance.
If a patient comes into direct contact with cryogens after a quench, frostbite can occur.
A quench can be triggered manually, or can occur spontaneous due to a range of mechanical or environmental factors.
There will be an instant, temporary increase in the magnetic field until it begins to gradually decline because of a rise in resistance.
The purpose of shielding the magnet is:
Make the magnetic field stronger and more homogeneous
Decrease the size of the fringe field
Allow staff to bring metallic objects closer to the magnet
Surprise staff as they walk into the room with scissors
Decrease the size of the fringe field
After a quench, the cryogen vent system should be inspected for damage. True or False?
True
False
True
If the magnet quenches during a scan, the most important thing is to vent the room properly to allow the helium to escape. True or False?
True
False
False
System SAR monitoring DOES take into account the ambient room temperature and humidity. True or False?
True
False
True
Which of the following is NOT an acceptable method of screening a patient prior to entering zone 4?
Surgical history questionnaire
Additional x-ray images
Patient’s prior scans and reports
Referring diagnosis
Patient interview
Referring diagnosis
The ACR recommends an access-controlled door into ___________ by way of locked door with a keyed entry, including passcodes or proximity badges.
Zone 1
Zone 2
Zone 3
Zone 4
Zone 3
The volume of helium does not change when it changes from a liquid to a gas. True or False?
True
False
False
Cryogen vent systems should be inspected at least annually. True or False?
True
False
True
In order to maintain superconductivity, __________ are used to reduce resistance to as low as possible and achieve field strengths higher than 0.6T.
Body coils
Cryogens
Gadolinium contrast agents
Niobium titanium wire loops
Spatial gradients
Cryogens
The liquid to gas expansion ratio for helium is:
1:1
Too large to measure
1:50
1:754
1:754
Patient transport brings a patient from the floor to the MRI department. Because all hospital personnel have completed Level I MRI safety training, what MRI safety zones is the transporter permitted to enter?
Only Zones 1 and 2
None, since they do not work in the MRI department
All Zones, however they may not be responsible for the patient in Zone 4
They must stop at Zone 4
All Zones, however they may not be responsible for the patient in Zone 4
The external cryogen discharge point is classified as a part of ________ and, if freely accessed by a member of a Non-MR personnel group, could result in death.
Zone 1
Zone 2
Zone 3
Zone 4
Zone 3
Which zone acts as the interface between areas where the public are freely allowed and where patients are carefully screened and gowned?
Zone 1
Zone 2
Zone 3
Zone 4
Zone 2
Which zone is defined as “an area with direct exposure to a magnetic field?”
Zone 1
Zone 2
Zone 3
Zone 4
Zone 4
The benefit of shielding the magnet is that the size of the fringe field has been decrease and is easier to contain in a smaller scan room. True or False?
True
False
True
Which of the following job titles could NOT be members of Level 1 MR personnel?
clerical staff
cleaning staff
radiologist
technologist assistant
radiologist
Only serious MRI safety incidents should be reported to the site medical director. True or False?
True
False
False
Conventional metal detectors are not recommended for use in the MRI environment. True or False?
True
False
True
his personnel group is described as “Individuals who have received and passed minimal safety training requirements to ensure their safety while working in Zone 3 areas and cannot supervise or be responsible for the safety of others within zone 4” is:
Non-MR Personnel
Level 1 MR Personnel
Level 2 MR Personnel
Level 1 Clerical Personnel
Level 1 MR Personnel
All are possible job titles that could be members of the personnel 2 group EXCEPT:
clerical staff member
technologist
radiologist
technologist assistant
clerical staff member
Ferromagnetic detection should be used in conjunction with the thorough screening of persons and devices approaching Zone 4. True or False?
True
False
True
A ferromagnetic detection system can replace conventional screening for non-responsive MRI patients. True or False?
True
False
False
What is true of a quench?
The magnetic field rises temporarily, before falling after a quench.
A quench is not possible as long as the patient is out of the scanner.
A quench may happen silently so the operator is unaware.
There may be some cryogens that remain within the cryostat after a quench.
There may be some cryogens that remain within the cryostat after a quench.
For improved safety, ferromagnetic detection system should be used in Zone II. True or False?
True
False
False
Frost/ice on the cryostat means that:
Cryogens are keeping the system cold, nothing to worry about
The room is too humid and needs dehumidified
The cryostat vacuum seal may not be intact and service should be contacted
The magnet is too cold
The cryostat vacuum seal may not be intact and service should be contacted
In Zone 4, Level 1 MR personnel can be responsible for:
Screened patients
Only themselves
Radiologists
Other staff members
Only themselves
Conventional metal detectors are an acceptable screening tool in the MR environment. True or False?
True
False
False
Which zone is classified as an area that has direct access to the magnet, magnetic field, or cryogen discharge points?
Zone 1
Zone 2
Zone 3
Zone 4
Zone 3
Reporting safety incidents is an important component to quality improvement efforts. True or False?
True
False
True
An MR conditional code cart should be kept in Zone 4 so that patients can be treated quickly in the event of a code. True or False?
True
False
False
The strength of the handheld magnet used to test objects in the MR environment is:
At least as strong as a refrigerator magnet
At least 1,000 Gauss
The strongest magnet you can afford
Handheld magnets should not be used to test objects, we should rely on the MR labeling
At least 1,000 Gauss
All safety incidents in MRI site should be reported to the medical director as soon as possible. True or False?
True
False
True
During a quench, helium gas is ______ than air, so it is important to stay ________________.
heavier/standing upright
the same density/outside the scan room
lighter/low to the floor
hotter/hydrated
lighter/low to the floor
The properties of gaseous helium include all of the following, except:
Lighter than air
Colorless
Heavier than air
Odorless
Heavier than air
Which zone is classified as an area freely accessible to persons with no direct involvement with MRI?
Zone 1
Zone 2
Zone 3
Zone 4
Zone 1
According to the ACR, which of the following is an appropriate security method to the entry doors separating secured zones in an MRI department?
A locked door with keypad entry or proximity badge access
An unmanned, unlocked door with a sign on it that reads “Do not enter unless accompanied by Level 2 MR Personnel””
A locked door with a padlock
A member of Level 2 MR Personnel guarding the entrance
A locked door with keypad entry or proximity badge access
In Zone 4, members of Level 2 MR Personnel can be responsible for all of the following, EXCEPT:
Patients
Accompanying visitors
Clerical staff
Radiologists
Radiologists
