With the emergence of novel hardware and software image acquisition improvements, magnetic resonance imaging (MRI) has the potential to become an important tool for assessing lung structure and function. In particular, the use of a hyperpolarized noble gas such as 129Xe has been used to explore structural and functional relationships in the lungs of both healthy subjects and patients with lung disease (1,2). In contrast to proton-based MRI imaging, 129Xe gas is used as a "contrast agent" to directly visualize the airways, and thus image ventilation. Whereas the normal density of gas is too low to produce an easily detectable signal, this is overcome by artificially increasing the amount of polarization per unit volume using optical pumping (3).