Phantom made of polyvinyl alcohol for visualization of temperature rising area due to ultrasound

In this study, we adopted polyvinyl alcohol (PVA) gel as a tissue-mimicking phantom to visualize the temperature rising area due to a focused ultrasound. The acoustic characteristics of the PVA phantom were analyzed experimentally for various concentrations. In addition, in order to investigate the characteristics of the temperature rising area, an image processing method is proposed. Using the method, changes in the discolored area on a thermochromic film inserted in the phantom were analyzed experimentally for various PVA concentrations and ultrasonic irradiation times.