Effects of inner volume field-of-view reduction on myocardial T2 mapping

Background Inner volume (IV) excitation was explored with respect to scan time reduction of cardiac gated double inversion recovery multi-echo fast spin echo (MEFSE) to measure the transverse relaxation time (T₂) in the myocardium. Methods The IV imaging was achieved by applying orthogonal slice selection for the excitation and refocusing pulses. The T₂ map accuracy was investigated using different excitation and refocusing pulses. The performance of IV-MEFSE was compared with MEFSE on phantoms and eight healthy volunteers, acquiring eight echo times in a single breath-hold. Results Compared with MEFSE, IV-MEFSE allowed a scan time reduction from 26 s to 16 s, but caused a T₂ overestimation of approximately 10% due to stimulated echoes. Conclusion IV successfully reduced the scan time to a single breath-hold feasible for many patients and remarkably facilitated the scan prescription, because there was no image aliasing concern. Care should be taken in using IV for T₂ mapping because of T₂ relaxation time overestimation.