Patent ID: 7972269

Claim:
An ultrasound diagnostic apparatus comprising: a tomogram forming unit for forming a tomogram of a diagnosis portion of an examinee by transmitting/receiving an ultrasound wave to/from the examinee via an ultrasound probe; color Doppler image forming unit for forming a color Doppler image based on a Doppler signal obtained from the diagnosis portion; a transparency control unit for controlling a degree of the transparency of the color Doppler image; an image processing unit for performing image processing on the tomogram and the color Doppler image; a display unit for displaying images obtained by the image processing unit, the tomogram and the color Doppler image being color displayed on the display unit, selection unit for selecting one or both of a luminance/hue color bar, which is based on the information of a velocity and/or variance of a blood flow, and/or a transparency color bar from a plurality of transparency color bars, which is based on the information of the variance, for alternatively or simultaneously displaying the luminance/hue color bar and/or the transparency color bar on the display unit; and wherein the transparency control unit for controlling a degree of transparency changes the relationship between the transparency and the variance, and changes the degree of transparency of the color Doppler image based on the changed relationship in accordance with the one transparency color bar selected by the selection unit, the image processing unit causes the color Doppler image to be displayed transparently, based on the changed degree of transparency, and the display unit displays at most the one transparency color bar selected by the selection unit.