Spatial distributions of optical and acoustic properties and correlations with temperature in cyclically frozen-thawed poly(vinyl alcohol) gel breast phantoms

摘要

Tissue mimicking phantoms are important for performance evaluation of imaging systems: in photoacoustics they need to accomplish both soft tissue optical and acoustic properties. PVA gels by freezing-thawing (F-T) have been used to simulate tissue properties. The microstructure, dependent on rate and extent of temperature cycling, is responsible for optical and acoustic properties. In F-T of larger phantoms, temperature differences in the mass are expected, resulting in a likely inhomogeneous distribution of properties in the phantom. We investigated speed of sound, acoustic attenuation, reduced optical scattering coefficient and microstructure: their variations are correlated with thermal differences between phantom surface and bulk.