MRI Safety
Technologists do this to prevent RF burns on the patient's shoulder, outer arms, legs and for larger patients, their stomachs.
Place RF padding between the patient and the bore of the MRI scanner.
What are the two acceleration methods commonly used with MRI.
ARC and ASSET
GE
Flex Coil
This is the reason that we do not scan whole body exams at 732 or MR2.
No coils within the scanner table
Where is the X/Y gradient the strongest?
at the surface of the bore
FOV, frequency / phase encoding and slice thickness
... there is a discrepancy between the ordered exam and the patient's history.
Radiologist
This is one of the greatest benefits of a large coil element.
deeper penetration
~penetration = radius of coil element
Elastography can be successfully scanned on all scanner except...
iMRI
True or False: All hospital gowns are safe during an MRI scan.
False
You are scanning an axial image of the orbits, you see aliasing in the eyes and back of the head; your frequency direction is.
R>L
... there is a discrepancy between the protocol loaded on the scanner and MedWiki.
Clinical Instructor
These scanners utilize the dino (inkspace) coil
MR2, MR4 (with IRB), PETMR and 732
Fetal exams should be scanned on 3T if the gestational period is below this.
32 weeks
"32 Rule": if under 32 weeks or under 32 BMI, fetal exam should be scheduled on the 3T
Where is RF padding routinely placed for a MR exam under GA.
between the tips of the fingers and thighs and between the knees /calves / feet / ankles.
The relationship between spatial resolution and FOV is this.
Inversely related
... you see a strange artifact
Clinical Instructor
When a patient for a Ped Brain on MR2 chooses not to watch a movie, this head coil should be used.
higher channel head coil - 32ch
We are protocoling a large patient with a large amount of ascites. After getting a radiologist's approval, we should schedule the patient on this scanner.
MR1: 1.5T
In order to reduce the dielectric effect
True or False: All Green oxygen tanks are MRI Safe
False
DAILY DOUBLE: Describe five 'main' ways to increase SNR and the effect that it have on spatial resolution.
1) Increase NEX - No effect, spatial resolution
2) Increase FOV - lower spatial resolution
3) Decrease Matrix - lower spatial resolution
4) Increase Slice Thickness - lower spatial resolution
5) Increase Oversampling - No effect, spatial resolution
6) Increase Bo (more H in NMV) - No effect
... you find yourself in a unique situation where you are unaware of the policy or procedure.
Management
The difference in number of coils elements between the MP coil and large MP coil is.
1
In a 1.5T scanner, the fat-water frequency difference will therefore be approximately this.
220 Hz
440 Hz at 3T