Synthetic aperture-based linear-array photoacoustic tomography considering the aperture orientation effect

The synthetic aperture-based linear-array photoacoustic tomography (PAT) was proposed to address the limited-view shortcomings of the single aperture, but the detection field of view (FOV) determined by the aperture orientation effect was not fully considered yet, leading to the limited-view observation and image resolution degradation. Herein, the aperture orientation effect was proposed from the theoretical model and then it was verified via both the numerical simulation and phantom experiment. Different orientations were enumerated sequentially in the simulation to approximate the ideal full-view case for the optimal detection FOV, considering the detection pattern of the linear-array transducer. As a result, the corresponding optimal aperture orientation was 60 if the synthetic aperture was seamlessly established by three single linear arrays, where the overlapped detection pattern was optimized from the individual linear-array transducer at the adjacent positions. Therefore, the limited-view artifacts were minimized and the image resolution was enhanced in this aperture orientation. This study showed that the aperture orientation had great influence on the optimal detection FOV in the synthetic aperture configuration, where the full-view imaging quality and enhanced image resolution could be achieved.