Separate evaluation of unilateral lung function using upright/supine CT in a patient with diaphragmatic paralysis

Radiology Case Reports

article

Takahiro Suzuki¹  Keisuke Asakura¹  Yoshitake Yamada¹  Minoru Yamada¹  Yoichi Yokoyama¹  Yu Okubo¹  Kyohei Masai¹  Kaoru Kaseda¹  Tomoyuki Hishida¹  Hisao Asamura¹  Masahiro Jinzaki¹ 

[1] Division of Thoracic Surgery, Keio University School of Medicine

关键词: CT;    Diaphragm;    Diagnostic Imaging;    Lung function;   

DOI  :  10.1016/j.radcr.2022.05.037

学科分类：生物化学工程

来源: University of Washington * Department of Radiology

【 摘 要 】

Background Unilateral diaphragmatic paralysis is a condition in which the unilateral diaphragm is paralyzed and elevated. Orthopnea due to lung compression by an elevated diaphragm in the supine position is common in patients with unilateral diaphragmatic paralysis. Although its symptom is posture-dependent, the effect of posture on lung function in unilateral diaphragmatic paralysis has not been studied. Computed tomography (CT) can be used to assess lung volume. However, conventional CT cannot be performed in the upright position. A pulmonary function test can be performed in both upright and supine positions. However, it cannot evaluate the function of each lung separately. Case presentation We report a case of a 79-year-old man with unilateral diaphragmatic paralysis. He presented with difficulty in inspiration, specifically in the supine position, and underwent both conventional supine CT and newly developed upright CT to assess the effect of posture on the function of each lung. The difference between expiratory and inspiratory lung volumes on CT in the supine position was less than that in the upright position by 46% and 4% on affected and healthy sides, respectively. We previously reported that the difference between expiratory and inspiratory lung volumes on CT correlated with inspiratory capacity on the pulmonary function test. A 46% decline in inspiratory capacity on the affected side in the supine position likely caused orthopnea in this patient. Conclusions Supine/upright CT is helpful to assess the influence of posture on unilateral lung function in patients with unilateral diaphragmatic paralysis.

【 授权许可】

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