Experimental Characterization of Optoacoustic Phantoms in Gel Wax and Polyvinyl Alcohol for Blood Pressure Measurements.

Abstract

An experimental evaluation and characterization of two transparent phantoms of arms, to be used as non-invasive experimental models to measure the blood pressure continuously, was performed in an in vitro study. The first phantom was made of polyvinyl alcohol (PVA) gel and the second phantom is based on gel wax. For the first time, a PVA and gel wax phantom for the arm, respectively, were developed, including tissue, radial artery, and ulnar and radius bones. The optoacoustic parameters of various samples for both phantoms were characterized and systematically compared, obtaining a maximum acoustic transmission of T=(78.3±1.9)% at 921 nm in the PVA hydrogel, due to its high transparency and homogeneity. The gel wax phantom possesses similar optical properties as the PVA hydrogel and presents acoustic characteristics similar to those of the soft tissue. Thus, both phantoms are well-suited as in vitro models for the development of new methods in optical-acoustic medical diagnosis.