Accelerated and high‐resolution cardiac T 2 mapping through peripheral k‐space sharing

Purpose To develop high‐spatial‐resolution cardiac T 2 mapping that allows for a reduced acquisition time while maintaining its precision. We implemented and optimized a new golden‐angle radial T 2 mapping technique named SKRATCH (Shared k‐space Radial T 2 Characterization of the Heart) that shares k‐space peripheries of T 2 ‐weighted images while preserving their contrasts. Methods Six SKRATCH variants (gradient‐recalled echo and balanced SSFP, free‐breathing and breath‐held, with and without a saturation preparation) were implemented, and their precision was compared with a navigator‐gated reference technique in phantoms and 22 healthy volunteers at 3 T. The optimal breath‐held SKRATCH technique was applied in a small cohort of patients with subacute myocardial infarction. Results The faster free‐breathing SKRATCH technique reduced the acquisition time by 52.4%, while maintaining the precision and spatial resolution of the reference technique. Similarly, the most precise and robust breath‐held SKRATCH technique demonstrated homogenous T 2 values that did not significantly differ from the navigator‐gated reference (T 2  = 39.9 ± 3.4 ms versus 39.5 ± 3.4 ms, P  > .20, respectively). All infarct patients demonstrated a large T 2 elevation in the ischemic regions of the myocardium. Conclusion The optimized SKRATCH technique enabled the accelerated acquisition of high‐spatial‐resolution T 2 maps, was validated in healthy adult volunteers, and was successfully applied to a small initial group of patients.