Artifacts
Spatial Res
Hardware
MR 101
Random MRI
100
What is Aliasing
Bonus question worth $50:
What can be done to reduce or eliminate this artifact?
100
Increasing FOV ___________ spatial resolution.
What is reduces or lowers?
100
It's the number of gradient coils in an MRI system
what is 6?
100
It's the fundamental equation in MR
What is the Larmour Equation?
100
It's the advantage to using Phased Array coils
What is to increasing SNR
200
What is cross talk or cross excitation?
Bonus question worth $300:
What can be done to reduce this artifact?
200
Decrease slice thickness from 5mm to 3mm results in this.
Decreasing spatial resolution
200
It is the hardware component that reconstructs the image Fourier Transformation
What is the Array Processor?
200
This has a very long T1 time
What is Cerebral Spinal Fluid?
200
A steep slice encoding gradient produces this.
What is a thinner slice
300
You do this to reduce or eliminate this artifact
What is increase phase and/or frequency encoding
300
You can do this to increase spatial resolution by increasing this without increasing scan time.
What is increase frequency encoding steps
300
It's what happens when you increasing the amplitude of the frequency encoding gradient.
What is making the FOV smaller.
300
It's the pulse sequence that starts with a 180 degree RF pulse
What is Inversion Recovery?
300
This can result in partial voluming effects
What is slices that are too thick?
400
What is di-electric artifact?
Bonus question worth $200.
This artifact is often seen in this situation?
400
Decreasing this always increases spatial resolution
What is decreasing voxel size
400
This describes the number of water-bound protons per volume of tissue.
What is Proton Density
400
It's an advantage of resistive or electro magnet MRI systems
What is turning "off" the magnet?
400
These coils are designed to increase the B0 homogeneity based on the area of interest.
What are shim coils.
500
Parallel Imaging: FOV too small or Factor too high
500
It's the reason decreasing slice thickness decreases SNR
What is sampling fewer water-bound protons?
500
It's what unit of measure of the B0 homogeneity.
What is ppm... Parts Per Million
500
It's the dephasing caused by susceptibility effects
What is T2' (prime)?
500
It's the structure circled.
What is the pulmonary artery?
600
Moire or "zebra-stripe" artifact
Bonus question with $200:
Name a possible solution to this artifact.
600
All other factors remaining the same, what is the effect of changing the FOV from a square FOV to a rectangular FOV. (Think it through)
No change
600
The phase encoding gradient is turn on at this time
Immediately after slice excitation
Bonus question with $300
What does the phase encoding gradient dephase?
600
It controls the amount of spins placed into the transverse plane in a gradient echo sequence
What is flip angle?
Bonus question worth $500
What is the signal intensity of a tissue that is heavily saturated by RF?
600
The brachiocephalic artery