Kum Ju Chae1, Jiwoong Choi2, Gong Yong Jin1, Eric A Hoffman3, Archana T Laroia4, Margaret Park5, Chang Hyun Lee6. 1. Department of Radiology, Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, South Korea. 2. Department of Internal Medicine, School of Medicine, University of Kansas, Kansas City, Kansas; Department of Mechanical Engineering, University of Iowa, Iowa City, Iowa; IIHR-Hydroscience and Engineering, University of Iowa, Iowa City, Iowa. 3. Departments of Radiology, Medicine and Biomedical Engineering, University of Iowa, Iowa City, Iowa. 4. Department of Radiology, College of Medicine, University of Iowa, Iowa City, Iowa. 5. Department of Radiology, Seoul National University Hospital, Seoul, South Korea. 6. Departments of Radiology, Medicine and Biomedical Engineering, University of Iowa, Iowa City, Iowa; Department of Radiology, College of Medicine, University of Iowa, Iowa City, Iowa; Department of Radiology, Seoul National University Hospital, Seoul, South Korea; Department of Radiology, Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul, South Korea. Electronic address: changhyun.lee.snuh@gmail.com.
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.
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 emphysemapatients 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 COPDpatients 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.
Authors: Jiwoong Choi; Kum Ju Chae; Gong Yong Jin; Ching-Long Lin; Archana T Laroia; Eric A Hoffman; Chang Hyun Lee Journal: Front Physiol Date: 2022-10-04 Impact factor: 4.755
Authors: Kyung Min Shin; Jiwoong Choi; Kum Ju Chae; Gong Yong Jin; Ali Eskandari; Eric A Hoffman; Chase Hall; Mario Castro; Chang Hyun Lee Journal: Respir Res Date: 2020-10-02
Authors: Ryan Baron; Stephen Kadlecek; Luis Loza; Yi Xin; Faraz Amzajerdian; Ian Duncan; Hooman Hamedani; Rahim Rizi Journal: Acad Radiol Date: 2021-07-14 Impact factor: 3.173
Authors: Julien G Cohen; Ludovic Broche; Mohammed Machichi; Gilbert R Ferretti; Renaud Tamisier; Jean-Louis Pépin; Sam Bayat Journal: Front Physiol Date: 2021-06-10 Impact factor: 4.566