Lung Ultrasound Surface Wave Elastography for assessing water content in a Sponge Phantom Model

The objective of this research is to model lung ultrasound surface wave elastography (LUSWE) for assessing water content of the lung for technique development. A sponge was used to model the structure of the lung with alveoli. A range of water content was modeled by injecting water into the sponge. A mechanical wave was applied to the phantom at five frequencies between 100 Hz and 300 Hz, where the surface speed was measured by ultrasound. Our results showed that surface wave speeds have no clear correlation with different water content measurements at low frequencies but decreased with water content for 250 and 300 Hz. The viscoelasticity was further analyzed by wave speed dispersion with frequency and found to increase with water content. This research may be useful for developing LUSWE for assessing water content of the lung for patients with lung edema.