Robust cardiac mapping at 3T using adiabatic spin-lock preparations

Purpose: The aim of this study is to develop and optimize an adiabatic (Figure presented.) ((Figure presented.)) mapping method for robust quantification of spin-lock (SL) relaxation in the myocardium at 3T. Methods: Adiabatic SL (aSL) preparations were optimized for resilience against (Figure presented.) and (Figure presented.) inhomogeneities using Bloch simulations. Optimized (Figure presented.) -aSL, Bal-aSL and (Figure presented.) -aSL modules, each compensating for different inhomogeneities, were first validated in phantom and human calf. Myocardial (Figure presented.) mapping was performed using a single breath-hold cardiac-triggered bSSFP-based sequence. Then, optimized (Figure presented.) preparations were compared to each other and to conventional SL-prepared (Figure presented.) maps (RefSL) in phantoms to assess repeatability, and in 13 healthy subjects to investigate image quality, precision, reproducibility and intersubject variability. Finally, aSL and RefSL sequences were tested on six patients with known or suspected cardiovascular disease and compared with LGE, (Figure presented.), and ECV mapping. Results: The highest (Figure presented.) preparation efficiency was obtained in simulations for modules comprising 2 HS pulses of 30 ms each. In vivo (Figure presented.) maps yielded significantly higher quality than RefSL maps. Average myocardial (Figure presented.) values were 183.28 (Figure presented.) 25.53 ms, compared with 38.21 (Figure presented.) 14.37 ms RefSL-prepared (Figure presented.). (Figure presented.) maps showed a significant improvement in precision (avg. 14.47 (Figure presented.) 3.71% aSL, 37.61 (Figure presented.) 19.42% RefSL, p < 0.01) and reproducibility (avg. 4.64 (Figure presented.) 2.18% aSL, 47.39 (Figure presented.) 12.06% RefSL, p < 0.0001), with decreased inter-subject variability (avg. 8.76 (Figure presented.) 3.65% aSL, 51.90 (Figure presented.) 15.27% RefSL, p < 0.0001). Among aSL preparations, (Figure presented.) -aSL achieved the better inter-subject variability. In patients, (Figure presented.) -aSL preparations showed the best artifact resilience among the adiabatic preparations. (Figure presented.) times show focal alteration colocalized with areas of hyper-enhancement in the LGE images. Conclusion: Adiabatic preparations enable robust in vivo quantification of myocardial SL relaxation times at 3T.