Wang JM, et al. - This paper aspired to quantify the regional gas transfer in idiopathic pulmonary fibrosis (IPF), with the aid of hyperpolarized ¹²⁹Xe MRI. This tool served as a rapid and well-tolerated exam which yielded region-specific quantification of interstitial barrier thickness and red blood cells (RBCs) transfer efficiency. It could be displayed as a robust tool for estimating the disease progression and therapeutic response in patients with IPF, sensitively and noninvasively, via additional development.