Apodization Schemes for Short-Lag Spatial Coherence Imaging

Short-lag spatial coherence (SLSC) imaging has been used to reduce clutter in ultrasound imaging by using echo coherence instead of signal magnitude as a contrast mechanism. Apodization strategies used to reduce off-axis scattering in conventional B-mode imaging are shown to extend coherence length and reduce SLSC contrast, resulting in decreased in image quality. It is possible to invert these schemes to increase scattering, improving contrast but not preventing recorrelation in hypoechoic regions. Adding channel noise to the signals can reduce the correlation and reduce clutter. Similarly, we propose adding uncorrelated properties to the aperture by randomizing magnitude or phase, taking advantage of their uncorrelated properties to modify the coherence curve. These effects can be exploited to relax system requirements and simplify SLSC imaging while improving image quality.