MRI SAFETY Flashcards
The intensity limit for a static magnetic field by the FDA for the entire population is?
4.0 Telsa
What does MR Safe logo appear as?
a green MR in a box logo
The intensity limit for a static magnetic field in clinical use is limited by the FDA to what field strength? (Clinical imaging in patients over one month of age and above)
8.0 Tesla
What does MR Unsafe logo appear as?
a red MR logo with a circle crossed out
The magnetic field that the MR technologist is most exposed to would be the?
Static Magnetic Field
ACR recommended Zone 1 signage designates an area intended for?
General Public
FDA safety levels for RF exposure during MR examination are defined by SAR restrictions, which are imposed to reduce the risk of?
systematic and/or thermal injury to patient
Risk factors of MR exposure with regards to SAR include all of the following except:
1. Cardiovascular disease
2. Hypotension
3. Obesity
4. Geriatric patients
Hypotension
An implant with a MR in a YELLOW triangle would require?
Strict manufacture guidelines be followed (field strength, scan parameters, duration) to ensure patient safety
What does the MR conditional logo appear as?
a yellow logo with MR enclosed in a Triangle
FDA guidelines dictate a level of concern when RF energy absorption produces an increase in body temperature of?
1 degree CELCIUS
The fringe magnetic field:
1. is eliminated by magnetic shielding
2. is eliminated by shimming
3. poses no safety risks if proper shielding is utilized
4. can cause nearby medical devices to malfunction
Can cause nearby medical devices to malfunction
RF energy is:
Low-energy, Non-ionizing radiation
ACR recommended Zone 2 signage designates an area intended for?
Unscreened MRI patients
An implant with a red MR logo in a circle crossed out would require?
A different imaging modality be used as the implant is unable to enter the magnetic field
What type of pulse sequence transmits the most RF to the patient and consequently can potentially have more SAR restrictions?
FSE - Fast Spin Echo
An implant with a Green MR logo in a box would require?
No restrictions on MR imaging approach
ACR recommended Zone 3 Signage designates an area intended for?
Screened MRI patients/personnel
The FDA recommends posting warning signs to indicate the ______ line?
5 Gauss
Which of the following is regulated by the FDA?
Acoustic noise
ACR recommended Zone 4 signage designates an area intended for?
Screened MRI patients under constant direct supervision of trained MR personnel
