Yoshitake Yamada1, Masako Ueyama2, Takehiko Abe3, Tetsuro Araki4, Takayuki Abe5, Mizuki Nishino6, Masahiro Jinzaki7, Hiroto Hatabu8, Shoji Kudoh9. 1. Department of Radiology, Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA 02215, USA; Department of Diagnostic Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Electronic address: yamada@rad.med.keio.ac.jp. 2. Department of Health Care, Fukujuji Hospital, Japan Anti-Tuberculosis Association, 3-1-24 Matsuyama, Kiyose, Tokyo 204-8522, Japan. Electronic address: ueyamam@fukujuji.org. 3. Department of Radiology, Fukujuji Hospital, Japan Anti-Tuberculosis Association, 3-1-24 Matsuyama, Kiyose, Tokyo 204-8522, Japan. Electronic address: takehikoabe@hotmail.com. 4. Department of Radiology, Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA 02215, USA. Electronic address: TARAKI@partners.org. 5. Department of Preventive Medicine and Public Health, Biostatistics Unit at Clinical and Translational Research Center, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Electronic address: abe.t@keio.jp. 6. Department of Radiology, Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA 02215, USA. Electronic address: Mizuki_Nishino11@dfci.harvard.edu. 7. Department of Diagnostic Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Electronic address: jinzaki@rad.med.keio.ac.jp. 8. Department of Radiology, Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA 02215, USA. Electronic address: hhatabu@partners.org. 9. Department of Respiratory Medicine, Fukujuji Hospital, Japan Anti-Tuberculosis Association, 3-1-24 Matsuyama, Kiyose, Tokyo 204-8522, Japan. Electronic address: skudoh@jatahq.org.
Abstract
OBJECTIVES: To quantitatively compare diaphragmatic motion during tidal breathing in a standing position between chronic obstructive pulmonary disease (COPD) patients and normal subjects using dynamic chest radiography. MATERIALS AND METHODS: Thirty-nine COPD patients (35 males; age, 71.3±8.4years) and 47 normal subjects (non-smoker healthy volunteers) (20 males; age, 54.8±9.8years) underwent sequential chest radiographs during tidal breathing using dynamic chest radiography with a flat panel detector system. We evaluated the excursions and peak motion speeds of the diaphragms. The results were analyzed using an unpaired t-test and a multiple linear regression model. RESULTS: The excursions of the diaphragms in COPD patients were significantly larger than those in normal subjects (right, 14.7±5.5mm vs. 10.2±3.7mm, respectively, P<0.001; left, 17.2±4.9mm vs. 14.9±4.2mm, respectively, P=0.022). Peak motion speeds in inspiratory phase were significantly faster in COPD patients compared to normal subjects (right, 16.3±5.0mm/s vs. 11.8±4.2mm/s, respectively, P<0.001; left, 18.9±4.9mm/s vs. 16.7±4.0mm/s, respectively, P=0.022). The multivariate analysis demonstrated that having COPD and higher body mass index were independently associated with increased excursions of the bilateral diaphragm (all P<0.05), after adjusting for other clinical variables. CONCLUSIONS: Time-resolved quantitative evaluation of the diaphragm using dynamic chest radiography demonstrated that the diaphragmatic motion during tidal breathing in a standing position is larger and faster in COPD patients than in normal subjects.
OBJECTIVES: To quantitatively compare diaphragmatic motion during tidal breathing in a standing position between chronic obstructive pulmonary disease (COPD) patients and normal subjects using dynamic chest radiography. MATERIALS AND METHODS: Thirty-nine COPDpatients (35 males; age, 71.3±8.4years) and 47 normal subjects (non-smoker healthy volunteers) (20 males; age, 54.8±9.8years) underwent sequential chest radiographs during tidal breathing using dynamic chest radiography with a flat panel detector system. We evaluated the excursions and peak motion speeds of the diaphragms. The results were analyzed using an unpaired t-test and a multiple linear regression model. RESULTS: The excursions of the diaphragms in COPDpatients were significantly larger than those in normal subjects (right, 14.7±5.5mm vs. 10.2±3.7mm, respectively, P<0.001; left, 17.2±4.9mm vs. 14.9±4.2mm, respectively, P=0.022). Peak motion speeds in inspiratory phase were significantly faster in COPDpatients compared to normal subjects (right, 16.3±5.0mm/s vs. 11.8±4.2mm/s, respectively, P<0.001; left, 18.9±4.9mm/s vs. 16.7±4.0mm/s, respectively, P=0.022). The multivariate analysis demonstrated that having COPD and higher body mass index were independently associated with increased excursions of the bilateral diaphragm (all P<0.05), after adjusting for other clinical variables. CONCLUSIONS: Time-resolved quantitative evaluation of the diaphragm using dynamic chest radiography demonstrated that the diaphragmatic motion during tidal breathing in a standing position is larger and faster in COPDpatients than in normal subjects.