Lung Ultrasound Surface Wave Elastography for Assessing Interstitial Lung Disease

Objective: Our goal is to translate lung ultrasound surface wave elastography (LUSWE) for assessing patients with interstitial lung disease (ILD) and various connective tissue diseases including systemic sclerosis (SSc). Methods: LUSWE was used to measure the surface wave speed of lung at 100, 150, and 200 Hz through six intercostal lung spaces for 91 patients with ILD and 30 healthy control subjects. In addition, skin viscoelasticity was measured on both forearms and upper arms for patients and controls. Results: The surface wave speeds of patients' lungs were significantly higher than those of control subjects. Patient skin elasticity and viscosity were significantly higher than those of control subjects. In dividing ILD patients into two groups, ILD with SSc patients and ILD without SSc patients, significant differences between each patient group with the control group were found for both the lung and skin. No significant differences were found between the two patient groups, although there were some differences at a few locations and at 100 Hz for skin viscoelasticity. Conclusion: Significant differences of surface wave speed were found between ILD patients and healthy control subjects for both the lung and skin. Significance: LUSWE may be useful for assessing ILD and SSc and screening early stage patients.