Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Nov;27(11):1540-1548.
doi: 10.1016/j.acra.2019.12.004. Epub 2020 Feb 3.

Relative Regional Air Volume Change Maps at the Acinar Scale Reflect Variable Ventilation in Low Lung Attenuation of COPD patients

Kum Ju Chae  1 , Jiwoong Choi  2 , Gong Yong Jin  1 , Eric A Hoffman  3 , Archana T Laroia  4 , Margaret Park  5 , Chang Hyun Lee  6
Affiliations
Free article

Relative Regional Air Volume Change Maps at the Acinar Scale Reflect Variable Ventilation in Low Lung Attenuation of COPD patients

Kum Ju Chae et al. Acad Radiol. 2020 Nov.
Free article

Abstract

Objectives: The purpose of this study was to investigate regional air volume changes at the acinar scale of the lung in chronic obstructive pulmonary disease (COPD) patients using an image registration technique.

Materials and methods: Thirty-four emphysema patients and 24 subjects with normal chest CT and pulmonary function test (PFT) results were included in this retrospective study for which informed consent was waived by the institutional review board. After lung segmentation, a mass-preserving image registration technique was used to compute relative regional air volume changes (RRAVCs) between inspiration and expiration CT scans. After determining the appropriate thresholds of RRAVCs for low ventilation areas (LVAs), they were displayed and analyzed using color maps on the background inspiration CT image, and compared with the low attenuation area (LAA) map. Correlations between quantitative CT parameters and PFTs were assessed using Pearson's correlation test, and parameters were compared between emphysema and normal-CT patients using the Student's t-test.

Results: LVA percentage with an RRAVC threshold of 0.5 (%LVA0.5) showed the strongest correlations with FEV1/FVC (r = -0.566), FEV1 (r = -0.534), %LAA-950insp (r = 0.712), and %LAA-856exp (r = 0.775). %LVA0.5 was significantly higher (P < 0.001) in COPD patients than normal subjects. Despite the identical appearance of emphysematous lesions on the LAA-950insp map, the RRAVC map depicted a wide range of ventilation differences between these LAA clusters.

Conclusion: RRAVC-based %LVA0.5 correlated well with FEV1/FVC, FEV1, %LAA-950insp and %LAA-856exp. RRAVC holds the potential for providing additional acinar scale functional information for emphysematous LAAs in inspiratory CT images, providing the basis for a novel set for emphysematous phenotypes.

Keywords: Chronic obstructive pulmonary disease; Emphysema; Image registration; Ventilation.

PubMed Disclaimer

Publication types

MeSH terms

LinkOut - more resources