Abstract #2553

Signal Dynamics During Dissolved-Phase Hyperpolarized 129Xe Radial MR Imaging of Human Lungs

Zackary I. Cleveland^1,2, Gary P. Cofer^1,2, Gregory Metz³, Denise Beaver³, John Nouls^1,2, Sivaram Kaushik^1,2, Monica Kraft³, Jan Wolber⁴, Kevin T. Kelly⁵, H Page McAdams², Bastiaan Driehuys^1,2

¹Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States; ²Radiology, Duke University Medical Center, Durham, NC, United States; ³Pulmonary and Critical Care Medicine, Duke University Medical Center, Durham, NC, United States; ⁴GE Healthcare, Amersham, United Kingdom; ⁵Radiation Oncology, Duke University Medical Center, Durham, NC, United States

It is now possible to directly image HP 129Xe dissolved in pulmonary gas exchange tissues of humans. Dissolved image intensity is dominated by relaxation, RF attenuation, and diffusive replenishment of dissolved 129Xe magnetization, which are influenced by pulmonary structure and physiology. Here, we develop a closed-form mathematical model of dissolved 129Xe magnetization dynamics during 3D radial imaging. Model predictions agree well with observations and can be used in image optimization. Because radial images acquire k-zero in each view, the model also allows dynamic information to be extracted from raw image data and may provide insights into global lung physiology.