Key points are not available for this paper at this time.
The reversible component of transverse relaxation time, R2’, enables the measurement of blood oxygenation, an important biomarker in several diseases. We propose a multi-echo HEPI technique to estimate R2’. HEPI combines GRE and SE and hence provides R2* and R2, when acquired at different echo-times. The accuracy of ME-HEPI in measuring R2’ is evaluated in a phantom in this work. The sensitivity of HEPI to different oxygenation levels, attained using respiratory challenge MRI, is studied in a healthy subject. This is also investigated using a simulation tool that simulates microvasculature and MR signal for varying oxygenation in the vessels.
Venugopal et al. (Wed,) studied this question.