Localisation and decoding of acoustoelectric brain imaging based on anisotropic brain models

Acoustoelectric imaging (AEI) combines electroencephalography (EEG) and transcranial focused ultrasound (tFUS) with the advantages of high temporal and spatial resolution, which is expected to provide safe, accurate and non-invasive neurofunctional imaging of the brain. Previous AEI studies were mainly based on isotropic homogeneous media, but the actual skull and brain white matter show anisotropic resistivity distributions, making it difficult for isotropic media to mimic the imaging results of real brain tissue. In this study, a multi-source AEI dipole localisation and decoding platform was established based on a 128-array ultrasound phase-controlled transducer. Using a phantom of imitation brain tissue and an isolated porcine brain tissue as experimental materials, the discharged dipole was raster scanned by focused ultrasound, and the acoustoelectric (AE) signals were decoded and analysed using an envelope decoding algorithm. The results show that the decoding and localisation of AE signals based on the anisotropic phantom was achieved, with a localisation error of less than 0.6 mm, a localisation signal-to-noise ratio (SNR) of at least 18.17 dB, a decoding half-peak width of at least 0.21 mm, and a decoding accuracy of 0.87. This study will further promote the development of AEI in the field of neuroimaging.