Free breathing lung MRI T1 in patients with idiopathic pulmonary fibrosis and healthy volunteers

Abstract

Introduction: Idiopathic pulmonary fibrosis (IPF) is a chronic lung condition where lung fibrosis occurs in heterogeneous regions of the lung. Changes in both regional and global lung T1 can be visualised using MRI, and may offer a radiation-free assessment of lung scarring. Objective: To compare lung T1 in patients with IPF and healthy volunteers acquired during inspiration, expiration and free breathing. Method: 16 patients with IPF (68±11 years, 10 male) and 10 healthy volunteers (29±7 years, 7 male) underwent 1.5T lung MRI using a 2D Look-Locker sequence during both inspiration breath-hold and free breathing. 4/16 patients and 8/10 volunteers also underwent imaging during expiration. Free breathing images were registered to a set of spatially aligned synthetic images which were created using a combined inversion recovery and respiratory model. Results: Compared to inspiration breath hold, mean lung T1 was significantly higher in free breathing (p=0.030) and expiration (p=0.034) in healthy volunteers. In patients with IPF, there were no significant differences between mean lung T1 in inspiration, expiration and during free breathing. Conclusion: Free breathing lung T1 was significantly lower in patients with IPF than in healthy volunteers.