Custom-made phantoms for thoracic ultrasound diagnostic and therapeutic applications in clinical practice

Abstract

Introduction and Aim: Ultrasound (US) provides valuable information in pathologies related to the lung parenchyma that are in direct contact with the pleura.The aim of this work was to design custom-made low-cost phantoms, whose characteristics mimic the lung parenchyma, to aid professionals in thoracic US imaging. Such phantoms would allow them to gain diagnostic and therapeutic capabilities in a clinical setting, in which infectious and neoplastic etiology diseases present a high prevalence. Methods: Water-based phantoms were fabricated using a 10% concentration of Polyvinyl Alcohol Cryogel (PVA-C) as gelling agent. Cellulose (20 mm) was employed as acoustic scatter at 1% concentration.In order to mimic the pathologies of interest, such as neoplasia or pleural effusion, different spherical inclusions, filled with solid or liquid, were placed at variable depths. Results: US characterization of each fabricated phantom was performed using a standard clinical US system (Z6 Mindray).Acquired images confirmed the similarity of the fabricated phantoms with the normal lung parenchyma.Furthermore, the measured speed of sound was within the limits of soft tissues reported in the literature. In addition, ultrasound images of the inclusions were validated. Interobserver variability did not affect the characteristics of the phantoms. Conclusion: The availability of these phantoms simulating the lung parenchyma provides tools to gain capabilities in the use of US imaging. Therefore, earlier and improved diagnosis of several pathologies could be achieved as well as faster and more precise interventions. Thus, the number of invasive surgical procedures and their associated costs would be reduced.