Data weighting for principal component noise reduction in contrast enhanced ultrasound

Pulse inversion ultrasound is a mechanism for preferentially displaying contrast agent in blood vessels while suppressing signal from tissue. We seek a method for identifying and segmenting areas of the liver with similar statistically significant time intensity curves. As a first step in this process, a method of weighting Rayleigh distributed ultrasound image data before principal components analysis is presented. Simulation studies show that relative mean squared error can be reduced by 14% when the correct number of dimensions in selected. Our method is tested on an in vitro ultrasound phantom showing slightly increased error suppression, and is demonstrated on a clinical liver scan, showing decreased correlation between signals in the low intensity range.