Sound transmission through normal and diseased human lungs

A system for monitoring sound transmission through the human lung is described and the possibility of using this information in order to construct a functional map of the lung is investigated. Lung morphology (structure) may be monitored by using X-rays or computerised axial tomography (CAT). However, the size, cost and the possible adverse effects of high doses of X-rays make these techniques unsuitable for routine use. The speed of sound transmission through parenchyma (lung tissue) is a function of the size of the alveoli (air sacs). Therefore, by measuring the speed of sound through the lungs it may be possible to detect areas of collapsed alveoli. This would provide a simple, cheap, and non-invasive technique for monitoring certain lung abnormalities