Constrained Adaptive Beamforming for Improved Contrast in Breast Ultrasound

Ultrasonic imaging plays an important role as an adjunct to mammography, with an emerging role in breast cancer screening. Ultrasounds real-time nature, lack of ionizing radiation, and relative comfort for the patient make it an attractive imaging choice. Unfortunately, ultrasound image quality is often limited. We hypothesize that bright scatters seriously degrade ultrasound images by introducing image clutter. In the breast, bright off-axis echoes may originate from Coopers ligaments, structured glandular tissue, calcification, fat-soft tissue interfaces, or other structure. While we initially proposed using a variant of the Frost Adaptive Beamformer to reduce clutter, we have since discovered that this technique is non-optimal for our application. Extensive literature reviews have led us to utilize a recently proposed method, Spatial Processing Optimized and Constrained SPOC. In initial simulations this method not only dramatically reduces image clutter, but also yields super-resolution. We are actively refining this method while developing the experimental tools needed for in vivo testing.