Analysis of the role of shear waves in transcranial photoacoustic tomography

We report on an investigation of the role of shear waves in transcranial PAT brain imaging. Using a recently developed PAT image reconstruction method for use with layered media, we quantify the extent to which accounting for shear waves in the reconstruction method can improve image quality. The effects of shear waves propagating in the solid layer on the ability to estimate Fourier components of the object are investigated as a function of the thickness of the layer supporting shear waves as well as the incidence angle of the field in the planewave representation. These results clarify the role of shear waves in transcranial PAT image formation and indicate that further research is warranted to develop reconstruction algorithms that account for shear waves.