title: Regional lung volume differences between the side-lying and semi-prone positions.
abstract: [Purpose] This study aimed to clarify the differences in regional lung volume between the semi-prone (Sim's position) and side-lying position, and the optimal position for increasing lung volume. [Methods] Measurements were performed in both positions on both sides. Sim's position was inclined 45° forward from the side-lying position. A 1.5-T system with a fast advanced spin-echo sequence in the coronal plane was used for magnetic resonance imaging. [Results] The two positions did not significantly differ in total lung capacity and its subdivisions on both sides, except the left lung in the right side-lying position and right Sim's position. In the nondependent lung, the percentage lung volume of the dorsal segment was significantly higher in the right Sim's position than in the right side-lying position. However, no significant difference was observed between the left side-lying and left Sim's position. [Conclusion] The heart was displaced ventrally by gravity in Sim's position and leaned on the ventral parapet. The spaces for the expansion of the ventral and dorsal segments of the lung were decreased and increased in Sim's position, respectively. With a nondependent left lung, the increase in the percentage lung volume of the dorsal segment was greater in Sim's position than in the side-lying position.
authors.affiliation: Department of Physical Therapy, Faculty of Nursing and Rehabilitation, Konan Women's University, Japan.
authors.forename: Kyoushi
authors.initials: K
authors.lastname: Mase
authors.affiliation: Department of Physical Therapy, Uekusa Gakuen University, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Tagami
authors.affiliation: Department of Physical Therapy, Uekusa Gakuen University, Japan.
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Imura
authors.affiliation: Department of Physical Therapy, Ibaraki Prefectural University of Health Sciences, Japan.
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Tomita
authors.affiliation: Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Monma
authors.affiliation: Department of Physical Therapy, Faculty of Nursing and Rehabilitation, Konan Women's University, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Nozoe
authors.affiliation: Department of Physical Therapy, Faculty of Nursing and Rehabilitation, Konan Women's University, Japan.
authors.forename: Yukie
authors.initials: Y
authors.lastname: Takashima
keywords: Regional lung volume; Repositioning; Semi-prone