A Lung Phantom Model to Study Pulmonary Edema Using Lung Ultrasound Surface Wave Elastography

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Ultrasound Technology

Background:

• Lung ultrasound surface wave elastography (LUSWE) is an emerging method for evaluating superficial lung tissue stiffness.
• Pulmonary edema assessment often relies on imaging techniques that may have limitations.

Purpose of the Study:

• To investigate the feasibility of using LUSWE to quantify lung water content in a phantom model.
• To assess the relationship between water volume and the viscoelastic properties of lung tissue surrogates.

Main Methods:

• A lung phantom model using cellulose sponge was developed to simulate lung water.
• Surface wave propagation was generated by a shaker and measured using a 10-MHz ultrasound probe at 100, 150, and 200 Hz.
• Calculations of surface wave speed, shear viscosity, and shear elasticity were performed based on water volume.

Main Results:

• Surface wave speeds did not show a significant dependence on the injected water volumes.
• Shear viscosity of the sponge model increased proportionally with increasing water content.
• A subtle increase in shear elasticity was observed as water content increased.

Conclusions:

• Sponge viscoelasticity, specifically shear viscosity and elasticity, changes with water content.
• LUSWE is capable of detecting these changes in viscoelastic properties, indicating its potential for assessing lung water.
• This technique shows promise for non-invasive evaluation of pulmonary edema.