Three-dimensional photoacoustic tomography using acoustic line detectors

A method for phoatoacoustic tomography (PAT) is presented that uses line integrals over the acoustic wave field from a photoacoustic source for the reconstruction of a three-dimensional image. The line integrals are acquired with an optical line sensor based on a Mach-Zehnder interferometer. Image reconstruction is a two-step process. In the first step data from a scan of the line outside the object is used to reconstruct a linear projection of the source distribution. In the second step the inverse linear Radon transform is applied to multiple projections taken at different directions. This study focuses on the optimization of the first step using a frequency-domain algorithm and input data from a scan of the line detector in an L-shaped curve around the object. Simulations and a phantom experiment demonstrate that equally high resolution in all directions in the projection plane can be achieved with this method.