Lung MRI to predict response or lack of response to treatment in interstitial lung disease: initial observations on SSFSE/PROPELLER T2 match/mismatch

Ground-glass opacities (GGO) are frequently found in interstitial lung diseases (ILD) and may represent either active inflammation or subresolution interstitial fibrosis. We sought to investigate the ability of lung MRI to predict treatment response in individuals with ILD presenting with predominant GGO. Methods: prospective cohort, 15 participants presenting with ILD manifested as predominant GGO and referred for a new treatment regimen with a systemic glucocorticoid and/or an immunosuppressive agent, underwent 1.5 T lung MRI. SSFSE/PROPELLER T2 mismatch sign, relative signal intensity on T2-weighted images and relative enhancement of lung lesions were compared to functional response, defined as a greater than 10% increase in forced vital capacity in 10 weeks (primary endpoint).SSFSE/PROPELLER T2 match/mismatch was able to discriminate responders from nonresponders for the primary endpoint in 12 of 15 participants (80% accuracy, p = 0.026) for readers 1 and 2, and in 13 of 15 participants (87% accuracy, p = 0.011) for reader 3, with interrater agreement of 87% between readers 1 and 2 (Cohen's kappa coefficient of 0.732) and 93% between readers 1/2 and 3 (Cohen's kappa coefficient of 0.865).SSFSE-PROPELLER T2 match/mismatch was predictive of treatment response status in this group of ILD patients. Abbreviations FVC: forced vital capacityGGO; ground-glass opacities; HRCT: High-Resolution Computed Tomography; ILD: interstitial lung disease; LAVA: Liver Acquisition with Volume Acceleration; mMRC: modified Medical Research Council dyspnea score; MRI: Magnetic Resonance Image; PROPELLER: Periodically Rotated Overlapping Parallel Lines with Enhanced Reconstruction; SI: signal intensity; SSFSE: Single-Shot Fast Spin Echo.