A polyacrylamide gel phantom for radiofrequency ablation

Abstract

A polyacrylamide gel (PAG) containing bovine serum albumin (BSA) is introduced as a new tissue-mimicking phantom for the purpose of visualizing three-dimensional coagulation temperature distribution during radiofrequency ablation (RFA). The coagulation temperature of the phantom can be changed at the same range of biological tissue (50-60°C) by adjusting the pH from 4.3 to 4.7. The phantom is transparent except in thermal coagulation regions which are ivory white. The physical properties of the phantom, such as density, electrical conductivity and specific heat capacity, are very favorable, similar to those of soft tissues. We illustrate the usefulness of the phantom in visualizing RFA lesions. This phantom has magnetic resonance properties which change drastically upon thermal coagulation, enabling its use for the characterization of RFA device, quality assurance, treatment planning and treatment verfication. The PAG containing BSA, whose pH was adjusted from 4.3 to 4.7, is an attractive tissue-mimicking phantom suitable for RFA investigations.