Gradient echo sequences T1 T2 PD

What is the specific flip angles used in gradient echo sequences

they can be variable starting 0-180 degree
what are the typical values in gradient echo with a long tr and short tr
- long: 100ms+
- short tr: less than 50 ms
what are the values of a low flip angle range

between 5-20degress
what are the large flip angles used in gradient sequences

70+ degree
in order to obtain a t1 weighted image in gradient sequence yo need what te? tr? flip?
- short tr
- short te
- and large flip angle
How do you produce a t2 weighted image
- Long tr and te
- small flip angle
How do you produce a pd image
- long tr short te
- small flip angle
Using a long TE enhances T2 and T2* contrast.
t or F

True because Long TEs always give the spins more time to dephase before the echo is read, therefore increasing T2 contrast. This is true in spin echo and gradient echo sequences.
Combining a low flip and long TR results in saturation.
true or false

False. This combination results in the vectors being flipped through a small angle while giving them a long time to recover using a long TR. Hence the vectors never exist beyond the transverse plane in saturation.

Author

MriSensei

338425

Card Set

Gradient echo sequences T1 T2 PD

Description

mri

Updated

2018-02-26T16:41:33Z

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