Computational study of lung lobar sliding and the mechanics of breathing

To properly breathe, the lungs must be capable of both expanding and changing their shape to a large extent. This demanding task must be performed efficiently and repeatedly over the span of many years. Some researchers have speculated that one aspect of the lungs that helps them adapt to large changes in shape so effectively is the sliding motion between lobes of the lungs. The lungs are typically divided into five regions of roughly the same size called lobes (two on the left lung and three on the right) divided by fissures that allow the lobes to slide against each other. However, some people have missing or incomplete lobar fissures which may alter how effectively their lungs can change shape.

The goal of this project was to develop computer simulations of the lungs capable of answering questions about lobar sliding such as how lobar sliding affects the lungs’ ability to change shape. By performing simulations of the lungs where lobar sliding was and was not allowed and comparing the results, we found evidence consistent with the hypothesis that lobar sliding helps the lungs more effectively change shape. In addition, the computer simulations were used to better understand what the motion of lobar sliding might look like inside the body. This information may help physicians recognize abnormal motion in the lungs or improve technologies that seek to accurately predict how the lung will move such as radiation therapies for lung cancer patients.