Theoretical application of short-lag spatial coherence to photoacoustic imaging

Short-Lag Spatial Coherence (SLSC) is a beamforming technique that was initially developed for ultrasound imaging, then applied to photoacoustic imaging with sizable improvements in contrast and signal-to-noise ratios, when compared to traditional delay-and-sum beamforming. Although the SLSC beamformer was applied to experimental photoacoustic images, the theory describing its performance in photoacoustic images was never derived. The objective of this work is to derive and evaluate spatial coherence theory for SLSC beamforming of photoacoustic images, which is critical to understanding the breadth of potential applications and their associated limitations.