Abstract: An ultrasound imaging system for displaying edge-enhanced topographic flow power data surrounded by B-mode anatomical data without masking out any significant edge-enhanced topographic flow power data and without displaying any significant flow power background noise. An improved high-pass topographic filter is used to enhance the edges of the flow in the displayed image in both the horizontal (lateral) and vertical (range) directions. The two-dimensional topographic filter is a digital filter with three taps in each dimension and is incorporated in the acoustic line memory. Also, the raw flow power data is compressed down to 7 bits in such a way that the transfer function is shifted away from zero input power. In this way, the system gain can be set to effectively zero out most of the background noise. After the flow power data passes through the high-pass topographic filter, it is mapped to values between -128 and +127 (8 bits) with zero in the middle.