T2-weighted PROPELLER MRI is not suitable for pulmonary emphysema quantification

To the Editor:

We read with interest the recent publication by Meier-Schroers M et al. [1] related to the Quantitative and Qualitative Assessment of Pulmonary Emphysema with T2-Weighted PROPELLER MRI in a High-Risk Population Compared to Low-Dose CT. Quantifying emphysema is a crucial issue for the phenotype and the follow-up of chronic obstructive pulmonary disease (COPD) patients who will need to undergo chest computed tomography (CT) scans periodically. Thus, lung magnetic resonance imaging (MRI) could be a non-ionizing noninvasive imaging alternative. However, due to low intrinsic proton density of the lung, cardio respiratory motion effects and a very short T2* caused by air-tissue interfaces, the parenchymal MR signal acquired using standard sequences is very low. In addition, emphysema characterized by tissue destruction, decreased perfusion and hyperinflation further reduces the parenchymal MRI signal.

• References

• 1 Meier-Schroers M, Sprinkart AM, Becker M. et al. Quantitative and Qualitative Assessment of Pulmonary Emphysema with T2-Weighted PROPELLER MRI in a High-Risk Population Compared to Low-Dose CT. ROFO Fortschr Geb Rontgenstr Nuklearmed 2018; 190: 733-739
• 2 Smith BM, Austin JHM, Newell JD. et al. Pulmonary Emphysema Subtypes on Computed Tomography in Smokers. Am J Med [Internet]. 2014; 127: 94.e7-94e.23
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