MR Elastography of Human Lung Parenchyma: Feasibility of Echo-Planar and Respiratory-Triggered Echo-Planar Imaging

Yogesh K. Mariappan¹, Kevin J. Glaser¹, Rolf D. Hubmayr², Richard L. Ehman¹, Kiaran P. McGee¹

We have recently demonstrated that the shear stiffness of human lung parenchyma can be spatially resolved in vivo using spin echo breath-held MR Elastography (MRE) techniques. A disadvantage of this approach is relatively long breath-hold times limiting clinical translation particularly in patients with compromised respiratory function. To address this limitation a respiratory triggered EPI-based MRE sequence has been developed and tested. in vivo data in normal volunteers has demonstrated that changes in lung stiffness throughout the respiratory cycle can be quantified without the need for breath-held acquisitions while still maintaining phase-contrast signal-to-noise ratio compared to breath-held spin echo acquisitions.