T2 measurement of the human myocardium using a T2-prepared transient-state TrueFISP sequence

fast and motion-insensitive technique suitable for myocardial BOLD contrast imaging is presented. The method, termed TrueFISP, combines T-2 magnetization preparation with steadystate free precession (SSFP) imaging for T-2 relaxation mapping of the myocardium in healthy volunteers. The T-2 contrast-to-noise ratio (CNR) was optimized with the use of transient-state TrueFISP readout and half-Fourier readout with linear phase encoding. Single-slice myocardial T-2-weighted image was obtained within one heartbeat, and a single slice T-2 map of the myocardium was obtained in under 5-7 s. A respiratory navigator-gating method was incorporated for serial measurements and signal averaging, with the subjects breathing freely. The mean myocardial T-2 relaxation time measured in 12 healthy volunteers was 54 +/- 5.7 ms. Regional variations of T-2 values across the myocardium were 7%. Temporal variations across serial T-2 measurements in a transmural region covering similar to 0.5 cc of the left ventricular (LV) wall were 3.6% without signal averaging (number of excitations (NEX) = 1) and 1.7% with signal averaging (NEX = 10). According to our preliminary results, the T-2-TrueFISP method is expected to provide a robust and sensitive tool for clinical application of myocardial BOLD contrast imaging.