A Symmetrical Sensor Configuration for Acoustoelectric Brain Imaging

Basedon the Acoustoelectric (AE) effect, acoustoelectric brain imaging (ABI) is of potential for brain imaging with high spatial resolution. In this study, a symmetrical sensor configuration is designed for ABI. Taking four pairs of electrodes as an example, the electrodes are evenly distributed, and, for each electrode pair, corresponding recording electrode and reference electrode are symmetrical about the center of the measurement object. First, the influence of the angle between electrode sensor and dipole is investigated. Results show that the angle influences the image quality, and, when the angle is zero, the correlation coefficient is the largest, with a value of 0.89. Further, multi-electrode influence is also discussed. Compared with single electrode, multi-electrode behaves better in image reconstruction, with the correlation coefficient increased from 0.81(single) to 0.99(eight pairs). For multi-electrode, compared with that of uneven distribution, the average correlation coefficient of even distribution increases from 0.75 to 0.99. Finally, the performance of the proposed sensor configuration is tested with both simulation and phantom experiment. In simulation, compared with that of asymmetrical sensor, the average correlation coefficient of symmetrical sensor improves from 0.85 to 0.87. For phantom experiment, the AE signal SNR increases by 8.9% and correlation coefficient of reconstructed image increases from 0.63 to 0.65. Phantom experiment results validate that the symmetrical sensor is more accurate for ABI, which further verify the results in simulation. With high SNR of AE signal and more accurate reconstructed image, the proposed sensor configuration is of significance in the further research and application of ABI.