title: An analysis of the chest wall motions using the dynamic MRI in healthy elder subjects.
abstract: The objective of this study was to compare respiratory motions of the chest wall in the healthy elder subjects (N = 5; mean age, 71 years old) with those in healthy young subjects (n = 9; mean age, 29 years old). Thirty sequential images (scanning time, 0.4s per image) of dynamic MRI on sagittal and coronal planes were obtained while the subjects were deeply breathing. Lung volume change was simultaneously measured with pneumotachometer. In the elder subjects, dimensions of the middle and posterior parts of the diaphragm were linearly related to instantaneous lung volume. There were poor correlation between motion of the anterior diaphragm and transverse motions of the upper rib-cage and lower rib-cage. The contribution of individual part of the chest wall motion to a unit lung volume change, assessed by slope of the linear regression line, in elder subjects were not significantly different from those in young subjects. Either in the elder or young subjects, the middle and posterior parts of the diaphragm moved coordinately. We conclude that chest wall motion in the healthy elder subjects is not different from that in healthy young people and that middle and posterior parts of the diaphragm act as one functional unit during deep breathing.
authors.affiliation: Department of Medicine, Tokai University Oiso Hospital, 21-1 Gakkyo, Oiso-machi, Naka-gun, Kanagawa 259-0198, Japan. tetsuri@oiso.u-tokai.ac.jp
authors.forename: Tetsuri
authors.initials: T
authors.lastname: Kondo
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kobayashi
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Taguchi
authors.forename: Naoki
authors.initials: N
authors.lastname: Hayama
authors.forename: Sakurako
authors.initials: S
authors.lastname: Tajiri
authors.forename: Noriharu
authors.initials: N
authors.lastname: Yanagimachi
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology; D003964:Diaphragm / Q000502:physiology; D006262:Health; D006801:Humans; D008168:Lung / Q000502:physiology; D008279:Magnetic Resonance Imaging; D008297:Male; D009068:Movement / Q000502:physiology*; D012119:Respiration; D035441:Thoracic Wall / Q000502:physiology*