In this study, a computationally efficient integration of delay-multiply-and-sum (DMAS) photoacoustic (PA) image reconstruction and minimum-variance beamformation (MV), named as MV-HDMAS, is developed to drastically improve the lateral resolution and suppress sidelobes; thus significantly improving the contrast. Here, a novel Hilbert transform based DMAS (H-DMAS) is adopted, which allows seamless integration with MV. MV here is used to optimize the aperture apodization for H-DMAS. No oversampling and band pass filtering as in radio frequency DMAS are required. Experimental results confirm not only the superior lateral resolution in the proposed MV-HDMAS but also comparable image contrast to DMAS counterpart.
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