IMAGE CORRECTION FOR TRANSCRANIAL PLANE WAVE IMAGING

In order to study the influence of skull on transcranial ultrasound imaging, we use linear acoustic equation and finite difference method to simulate the transcranial ultrasound field without skull and with skull respectively. The acoustic field is generated by a linear array with 64 elements and central frequency of 2.4MHz. Because of the difference between acoustic parameters of skull and those of surrounding tissues, the image with the skull in the model is seriously distorted, which has imaging target positions shifted, low imaging brightness, low contrast and low resolution, comparing to the image without the skull in the model. Therefore, this paper proposes a corrective method of received signal phase. The results show that after the delay compensation, the positions of the imaging targets are reset to the correct positions, and the image brightness, contrast and resolution are significantly improved.