|| Checking for direct PDF access through Ovid
A fast and motion-insensitive technique suitable for myocardial BOLD contrast imaging is presented. The method, termedT2-TrueFISP, combinesT2 magnetization preparation with steady-state free precession (SSFP) imaging forT2 relaxation mapping of the myocardium in healthy volunteers. TheT2 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 myocardialT2-weighted image was obtained within one heartbeat, and a single sliceT2 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 myocardialT2 relaxation time measured in 12 healthy volunteers was 54 ± 5.7 ms. Regional variations ofT2 values across the myocardium were 7%. Temporal variations across serialT2 measurements in a transmural region covering ˜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, theT2-TrueFISP method is expected to provide a robust and sensitive tool for clinical application of myocardial BOLD contrast imaging. Magn Reson Med 57:960–966, 2007. © 2007 Wiley-Liss, Inc.