Quantifying Cardiogenic Oscillations of Hyperpolarized 129Xe Gas Exchange MR Spectra in a Healthy Reference Cohort

Hyperpolarized 129Xe gas exchange MR spectra exhibit cardiogenic oscillations that have been found to distinguish between groups of cardiopulmonary diseases. Specifically, oscillations in the amplitude of the 129Xe red blood cell (RBC) resonance can differentiate pre-capillary and post-capillary pulmonary hypertension. Before diagnostic relevance can be established, these oscillations must be robustly quantified and definitive reference values must be determined. Here, we compare oscillation quantification using a constrained peak-finding algorithm against results from conventional sine fitting. We then employ a well-curated healthy cohort to establish reference values for cardiogenic oscillations in 129Xe RBC spectral parameters, using both methods.