Which parameter set would produce a T2 weighted image?

Which parameter set would produce a T2 weighted image?

• A. TE: 60 TR: 600
• B. TE: 200 TR: 500
• C. TE: 180 TR: 1200
• D. TE: 25 TR: 1750

Answer: (C)

T2 weighting is achieved when image contrast is driven mainly by differences in transverse relaxation (T2) rather than by T1 recovery or proton density. To emphasize T2, you use a long echo time so tissues with longer T2 retain signal longer, and you use a long repetition time so tissues have time to recover and T1 effects are minimized. In short, long TE increases T2 contrast, and long TR reduces T1 weighting. The parameter set described with a TE of 180 ms and a TR of 1200 ms fits this approach: both values are relatively long, so T2 differences dominate the image appearance and T1 influences are reduced. The other options either have a short TE, which weakens T2 contrast, or a short TR, which leaves T1 differences more prominent, or a very long TR with a very short TE, which leans toward proton density rather than T2. Hence this combination best yields a T2 weighted image.

T2 weighting is achieved when image contrast is driven mainly by differences in transverse relaxation (T2) rather than by T1 recovery or proton density. To emphasize T2, you use a long echo time so tissues with longer T2 retain signal longer, and you use a long repetition time so tissues have time to recover and T1 effects are minimized. In short, long TE increases T2 contrast, and long TR reduces T1 weighting.

The parameter set described with a TE of 180 ms and a TR of 1200 ms fits this approach: both values are relatively long, so T2 differences dominate the image appearance and T1 influences are reduced. The other options either have a short TE, which weakens T2 contrast, or a short TR, which leaves T1 differences more prominent, or a very long TR with a very short TE, which leans toward proton density rather than T2. Hence this combination best yields a T2 weighted image.