LESION CONTRAST ENHANCEMENT IN MEDICAL ULTRASOUND IMAGING

Methods for improving the contrast-to-noise ratio (CNR) of low-contras t lesions in medical ultrasound imaging are described, Differences in the frequency spectra and amplitude distributions of the lesion and it s surroundings can be used to increase the CNR of the lesion relative to the background, Automated graylevel mapping is used in combination with a contrast-weighted form of frequency-diversity speckle reduction , in clinical studies, the techniques have yielded mean CNR improvemen ts of 3.2 dB above ordinary frequency-diversity imaging and 5.6 dB ove r sharper conventional images, with no postprocessing graylevel mappin g.