Function and microstructure by hyperpolarized gas MRI

The ability to regionally assess lung function and/or microstructure has both scientific and diagnostic advantages, and yet the lung is notoriously difficult to image. New techniques and hardware are being developed that may allow pulmonary ¹H MRI to rival CT for diagnostic value in the coming years, but hyperpolarized gas MRI via ³He or ¹²⁹Xe provides exceptional detail in terms of real-time ventilation and quantification of microstructure and regional function. The purpose of this chapter is to detail some, but not all, of the aspects of hyperpolarized gas MRI that relate to regional function (ventilation imaging) and microstructure (diffusion imaging). Through an understanding of regional structure-function relationships, we can better understand the pathophysiology of lung disease and the potential for future therapeutic remedies.