In MRI, TR stands for the _____.

In MRI, TR stands for the _____.

• A. Time to echo
• B. Time to repeat
• C. Time to image
• D. Time to measure

Answer: (B)

Repetition time is the interval between the start of one excitation pulse and the start of the next. This timing determines how much longitudinal magnetization can recover before the next pulse, which directly influences image contrast and total scan time. Short repetition times limit recovery, boosting T1 differences and speeding up acquisition; long repetition times allow more recovery, reducing T1 weighting and often improving signal stability. Time to Echo is a separate parameter that governs T2 contrast, measured from the excitation to the echo. The concept described here aligns with the idea of the repetition interval between successive RF pulses.

Repetition time is the interval between the start of one excitation pulse and the start of the next. This timing determines how much longitudinal magnetization can recover before the next pulse, which directly influences image contrast and total scan time. Short repetition times limit recovery, boosting T1 differences and speeding up acquisition; long repetition times allow more recovery, reducing T1 weighting and often improving signal stability. Time to Echo is a separate parameter that governs T2 contrast, measured from the excitation to the echo. The concept described here aligns with the idea of the repetition interval between successive RF pulses.