A Numerical Analysis of Semi-dry Coupling Methodology in the Application of Horizontal Photoacoustic Brain Imaging

The Photo-acoustic imaging methodology contains ultrasonic transducers that utilize an acoustic couplant layer. Transmission from an ultrasonic sensor is best received with a couplant to minimize degradation and signal loss, such as gaps or air bubbles. In the application of horizontal photo-acoustic brain imaging, water is commonly used as a couplant for ultrasonic transducers due to its acoustic properties. The most important challenge of using water is contact with the infant’s head and its discomfort for the patient. In this study, based on the finite element method (FEM) we explored the feasibility of the patented semi-dry coupling methodology, including a thin layer of Aqualene as the dry couplant with water inside of it, to be used in photoacoustic computed tomography (PACT) systems.