repetition time


rep·e·ti·tion time (TR),

in magnetic resonance imaging, the time between repetitions of the pulse sequence.

repetition time

An MRI term for the timespan between successive pulse sequences applied to the same slice, which is delineated by initiating the first radio frequency (RF) pulse of the sequence and then repeating the same RF pulse at a time t. TR variations are important in controlling image contrast characteristics. Short TRs (< 1000 ms) are used to enhance T1 contrast; long TRs (> 1500 ms) are commonly used to enhance T2 contrast. TR is a major factor in total scan time.

rep·e·ti·tion time

(TR) (rep'ĕ-tish'ŭn tīm) magnetic resonance imaging The time between repetitions of the pulse sequence.