MRI physics stuff Flashcards
Gadapentate = ?
Ionic or non-ionic?
Linear or macrocyclic?
Magnavist
Ionic
Linear
Gadobenate = ?
Ionic or non-ionic?
Linear or macrocyclic?
Multihance
Ionic
Linear
Gadoxetate = ?
Ionic or non-ionic?
Linear or macrocyclic?
Eovist
Ionic
Linear
Gadodiamide = ?
Ionic or non-ionic?
Linear or macrocyclic?
Omniscan
Nonionic
Linear
Gadoteridol = ?
Ionic or non-ionic?
Linear or macrocyclic?
Prohance
nonionic
macrocyclic
Gadobutrol = ?
Ionic or non-ionic?
Linear or macrocyclic?
Gadovist
Nonionic
Macrocyclic
Gadoterate = ?
Ionic or non-ionic?
Linear or macrocyclic?
Dotarem
nonionic
macrocyclic
Nephrogenic systemic sclerosis (NSF) is only associated with which gadolinium based contrast media?
A few linear contrast media including:
Magnevist
Omniscan
Optimark
MOO
For 2D MRI, table time is equal to what?
2D Table time = TR * Phase matrix * NEX
Where,
TR = Time between each RF pulse
NEX = Number of times each set of encoding steps is repeated per TR
3D MRI table time is equal to?
3D Table time = TR * Phase matrix * NEX * # of slices
FSE time = ?
FSE time = 1/(echo train length)
What are 4 things that improve MRI spatial resolution?
- Small voxel
- Small FOV
- Larger matrix
- Thinner slices ( Thin transmit bandwidth/Steep slice select gradient)
What are 9 things that improve SNR in MRI?
- Stronger magnet
- Long TR
- Big FOV
- Larger slices (wide transmit bandwidth/shallow slice select gradient)
- more NEX
- Short TE
- Small matrix
- Small receiver bandwidth
- appropriate coil size
What is the primary determinant of noise in MRI?
Receiver bandwidth
Increase RB –> increase noise –> decrease SNR
What is SAR?
Specific absorption rate: ability to heat patient with RF pulse energy