Method for evaluating image quality of elastic image, and ultrasonic diagnostic apparatus

An ultrasonic diagnostic apparatus comprising:

• a probe configured to transmit/receive ultrasonic waves to/from an object to be examined;
• an elasticity information calculating unit configured to calculate elasticity information based on the ultrasonic waves received by the probe;
• an elastic image constructing unit configured to generate a plurality of elastic image frames based on the elasticity information;
• a display configured to display the plurality of elastic image frames;
• and
• an elastic image evaluating unit configured to:
• detect fluctuation cycles of the elasticity information, wherein the fluctuation cycles are produced by pressing the probe toward the region of interest and releasing the probe away from the region of interest,
• divide the plurality of elastic image frames into a plurality of groups, wherein each group of the plurality of groups includes a plurality of frames,
• calculate a feature quantity of the each group by using respective data,
• obtain an instability of the respective groups based on differences of feature quantities between a certain group and one or a plurality of groups that are detected prior to the certain group,
• evaluate elastic images of the respective groups by making a score of the elastic images having a small instability higher than a score of the elastic images having a large instability,
• generate a strain graph with the fluctuation pattern of the elasticity information, an instability graph and a movable time phase bar, and
• detect the movable time phase bar displayed in the strain graph with the fluctuation pattern and the instability graph in a time axis direction,
• wherein the elastic images and an evaluation of the elastic images are displayed in a time phase indicated by the movable time phase bar.