Imaging gravity-induced lung water redistribution with automated inline processing at 0.55 T cardiovascular magnetic resonance

Felicia Seemann; Ahsan Javed; Rachel Chae; Rajiv Ramasawmy; Kendall O'Brien; Scott Baute; Hui Xue; Robert J Lederman; Adrienne E Campbell-Washburn

doi:10.1186/s12968-022-00862-4

Imaging gravity-induced lung water redistribution with automated inline processing at 0.55 T cardiovascular magnetic resonance

J Cardiovasc Magn Reson. 2022 Jun 6;24(1):35. doi: 10.1186/s12968-022-00862-4.

Authors

Felicia Seemann¹, Ahsan Javed¹, Rachel Chae¹, Rajiv Ramasawmy¹, Kendall O'Brien¹, Scott Baute¹, Hui Xue¹, Robert J Lederman¹, Adrienne E Campbell-Washburn²

Affiliations

¹ Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
² Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA. adrienne.campbell@nih.gov.

Abstract

Background: Quantitative assessment of dynamic lung water accumulation is of interest to unmask latent heart failure. We develop and validate a free-breathing 3D ultrashort echo time (UTE) sequence with automated inline image processing to image changes in lung water density (LWD) using high-performance 0.55 T cardiovascular magnetic resonance (CMR).

Methods: Quantitative lung water CMR was performed on 15 healthy subjects using free-breathing 3D stack-of-spirals proton density weighted UTE at 0.55 T. Inline image reconstruction and automated image processing was performed using the Gadgetron framework. A gravity-induced redistribution of LWD was provoked by sequentially acquiring images in the supine, prone, and again supine position. Quantitative validation was performed in a phantom array of vials containing mixtures of water and deuterium oxide.

Results: The phantom experiment validated the capability of the sequence in quantifying water density (bias ± SD 4.3 ± 4.8%, intraclass correlation coefficient, ICC = 0.97). The average global LWD was comparable between imaging positions (supine 24.7 ± 3.4%, prone 22.7 ± 3.1%, second supine 25.3 ± 3.6%), with small differences between imaging phases (first supine vs prone 2.0%, p < 0.001; first supine vs second supine - 0.6%, p = 0.001; prone vs second supine - 2.7%, p < 0.001). In vivo test-retest repeatability in LWD was excellent (- 0.17 ± 0.91%, ICC = 0.97). A regional LWD redistribution was observed in all subjects when repositioning, with a predominant posterior LWD accumulation when supine, and anterior accumulation when prone (difference in anterior-posterior LWD: supine - 11.6 ± 2.7%, prone 5.5 ± 2.7%, second supine - 11.4 ± 2.9%). Global LWD maps were calculated inline within 23.2 ± 0.3 s following the image reconstruction using the automated pipeline.

Conclusions: Redistribution of LWD due to gravitational forces can be depicted and quantified using a validated free-breathing 3D proton density weighted UTE sequence and inline automated image processing pipeline on a high-performance 0.55 T CMR system.

Keywords: Cardiovascular magnetic resonance; Heart failure; Low-field MRI; Lung imaging; Lung water.

Publication types

Research Support, Non-U.S. Gov't
Research Support, N.I.H., Intramural

MeSH terms

Humans
Imaging, Three-Dimensional
Lung*
Magnetic Resonance Imaging / methods
Magnetic Resonance Spectroscopy
Predictive Value of Tests
Protons*

Substances

Protons