Retrospective Cohort Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. May 28, 2023; 15(5): 146-156
Published online May 28, 2023. doi: 10.4329/wjr.v15.i5.146
Chronic thromboembolic pulmonary hypertension is associated with a loss of total lung volume on computed tomography
Nanae Tsuchiya, Yan-Yan Xu, Junji Ito, Tsuneo Yamashiro, Hidekazu Ikemiyagi, David Mummy, Mark L Schiebler, Koji Yonemoto, Sadayuki Murayama, Akihiro Nishie
Nanae Tsuchiya, Junji Ito, Sadayuki Murayama, Akihiro Nishie, Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara 903-0125, Okinawa, Japan
Yan-Yan Xu, Department of Radiology, China-Japan Friendship Hospital, Beijing 100029, China
Tsuneo Yamashiro, Department of Radiology, Yokohama City University, Yokohama 2360027, Japan
Hidekazu Ikemiyagi, Department of Cardiovascular Medicine, Nephrology and Neurology, Graduate School of Medicine, University of the Ryukyus, Nishihara 9030125, Okinawa, Japan
David Mummy, Center for In Vivo Microscopy and Department of Radiology, Duke University, Durham, NC 27710, United States
Mark L Schiebler, Department of Radiology, University of Wisconsin-Madison, Madison, WI 53792, United States
Koji Yonemoto, Department of Biostatistics, School of Health Sciences, Faculty of Medicine, University of the Ryukyus, Nishihara 903-0215, Okinawa, Japan
Author contributions: All authors contributed to the study conception and design; Tsuchiya N, Xu YY, and Ito J performed the data collection and image interpretation; Tsuchiya N and Yonemoto K performed the statistical analysis; Tsuchiya N wrote the first draft of the manuscript; and all authors commented on previous versions of the manuscript and read and approved the final manuscript.
Supported by The Japan Society for the Promotion of Science, No. 24591782.
Institutional review board statement: This study was approved by the Ethics Committee for Clinical Research of University of the Ryukyus with waiver of informed consent (Approval No., 1039).
Informed consent statement: Our institutional review board approved this retrospective cohort study and waived the requirement for patient informed consent.
Conflict-of-interest statement: All authors report having no relevant conflicts of interest for this article.
Data sharing statement: The original anonymous dataset is available upon request from the corresponding author at
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Nanae Tsuchiya, MD, PhD, Lecturer, Department of Radiology, Graduate School of Medical Science, Tsuchiya, N (reprint author), Graduate School of Medical Science, University of the Ryukyus, 207 Uehara, Nishihara-Cho, Nakagami-Gun, Okinawa 903-0215, Japan.
Received: November 26, 2022
Peer-review started: November 26, 2022
First decision: March 15, 2023
Revised: April 4, 2023
Accepted: April 24, 2023
Article in press: April 24, 2023
Published online: May 28, 2023
Processing time: 178 Days and 2 Hours
Research background

In chronic thromboembolic pulmonary hypertension (CTEPH), about 20% of patients have lung restriction due to parenchymal scarring. We sometimes follow CTEPH patients who gradually lose lung volume. There is no report describing the temporal change in lung volume of CTEPH patients.

Research motivation

The loss of lung volume may be an important clinical consideration in CTEPH treatment.

Research objectives

The purpose of this study was to assess the temporal lung volume changes in CTEPH.

Research methods

Included in the study were patients with CTEPH who underwent two thoracic computed tomography (CT) examinations with a between-test interval that was greater than 6 mo. We also assessed controls matched by age, sex, and observation period. The lung volume was measured on the left and right sides by thin-slice CT scanning. Lung volume was automatically measured by lung analysis software. We analyzed the lung volume changes between the initial CT and follow-up CT in patients and controls by the Wilcoxon signed-rank test.

Research results

The total and right lung volumes were significantly reduced from the initial CT to the follow-up CT in the patients with CTEPH. In CTEPH patients, there was no significant change in the left lung volume. In controls, there were no significant changes in lung volume.

Research conclusions

In patients with CTEPH, the lung volume was reduced temporally. The right lung was more affected than the left lung by the lung volume reduction.

Research perspectives

Further study is needed to clarify whether this temporary increase in lung volume and subsequent regression may influence quality of life in patients with CTEPH.