Which MRI sequence has a TR of about 1200 ms and TE of 120 ms?

Which MRI sequence has a TR of about 1200 ms and TE of 120 ms?

• A. T1
• B. PD
• C. T2
• D. STIR

Answer: (C)

Understanding how repetition time and echo time shape MRI contrast is what this item tests. TE controls how much T2 decay is captured: a long TE lets tissues with longer T2 times stay bright and those with shorter T2 times fade more, producing T2-weighted contrast. TR largely determines how much T1 relaxation can recover between pulses; shorter TR emphasizes T1, while a long TR reduces T1 influence but isn’t the deciding factor by itself. A TE around 120 ms is clearly in the long-echo range, which is characteristic of T2 weighting. The TR around 1200 ms is longer than typical T1-weighted protocols (which use short TR) and isn’t as long as classic PD or STIR protocols, where TR is much longer. Put together, a long TE with a moderately long TR points to a T2-weighted sequence. So the sequence that matches a TE of about 120 ms and a TR of about 1200 ms is a T2-weighted imaging sequence.

Understanding how repetition time and echo time shape MRI contrast is what this item tests. TE controls how much T2 decay is captured: a long TE lets tissues with longer T2 times stay bright and those with shorter T2 times fade more, producing T2-weighted contrast. TR largely determines how much T1 relaxation can recover between pulses; shorter TR emphasizes T1, while a long TR reduces T1 influence but isn’t the deciding factor by itself.

A TE around 120 ms is clearly in the long-echo range, which is characteristic of T2 weighting. The TR around 1200 ms is longer than typical T1-weighted protocols (which use short TR) and isn’t as long as classic PD or STIR protocols, where TR is much longer. Put together, a long TE with a moderately long TR points to a T2-weighted sequence.

So the sequence that matches a TE of about 120 ms and a TR of about 1200 ms is a T2-weighted imaging sequence.