Ultrasound diagnosis apparatus and method of operating the same

1. An ultrasound diagnosis apparatus comprising:

an ultrasound probe configured to obtain ultrasound data of an object having blood vessels;

an image processor configured to:

extract a blood vessel area from an ultrasound image generated based on the ultrasound data,

extract a plaque area included in the blood vessel area,

determine a risk of plaque based on at least one of brightness information of the plaque area or a distribution state of brightness values of the plaque area, wherein the risk of plaque is determined to be high when a brightness level of the plaque area is equal to or greater than a first critical value or less than a second critical value that is less than the first critical value, and the risk of plaque is determined to be low when the brightness level of the plaque area is less than the first critical value and equal to or greater than the second critical value and the distribution state of the brightness values of the plaque area satisfies a predetermined criteria, and

determine a color representing the risk of plaque, based on the brightness level of the plaque area and the distribution state of the brightness values of the plaque area, by referencing a color map that correlates brightness levels and the distribution states of brightness values to colors representing the risk of plaque; and

a display configured to display the risk of plaque as the determined color.

2. The ultrasound diagnosis apparatus of claim 1 , wherein the image processor is configured to determine a surface shape of the plaque area, calculate a smoothness index (SI) representing a surface uniformity of the plaque area, based on the determined surface shape, and determine the risk of plaque based on the surface uniformity of the plaque area, and the risk of plaque is determined to be low when a surface of the plaque area is uniform and is determined to be high when the surface of the plaque area is not uniform.

3. The ultrasound diagnosis apparatus of claim 2 , wherein the image processor is configured to measure distances from a surface of a blood vessel to a surface of the plaque area in at least one of a circumferential direction or a lengthwise direction of the blood vessel, and calculate the SI of the plaque area based on a distribution of the measured distances.

4. The ultrasound diagnosis apparatus of claim 1 , wherein the image processor is configured to calculate the brightness level of the plaque area and the distribution state of the brightness values, based on a histogram of the brightness values of the plaque area.

5. The ultrasound diagnosis apparatus of claim 4 , wherein a value representing the distribution state of the brightness values is calculated based on at least one of a median value, an average value, a minimum value, a maximum value, a distribution value, or a standard deviation calculated from the histogram.

6. The ultrasound diagnosis apparatus of claim 1 , wherein the display is configured to display the risk of plaque by using at least one of a graph or a numerical value.

7. The ultrasound diagnosis apparatus of claim 1 , wherein the display is configured to indicate on a first region included in the plaque area a first color corresponding to a risk of plaque in the first region, and indicate a second color on a second region included in the plaque area corresponding to a risk of plaque in the second region.

8. The ultrasound diagnosis apparatus of claim 7 , wherein the display is configured to mark an icon on a region having a higher risk between the first region and the second region.

9. The ultrasound diagnosis apparatus of claim 1 , wherein the display is configured to indicate the distribution state of the brightness values of the plaque area as a texture.

10. A method of operating an ultrasound diagnosis apparatus, the method comprising:

obtaining ultrasound data of an object having blood vessels;

extracting a blood vessel area from an ultrasound image generated based on the ultrasound data, and extracting a plaque area included in the blood vessel area;

determining a risk of plaque based on at least one of brightness information of the plaque area or a distribution state of brightness values of the plaque area, wherein the risk of plaque is determined to be high when a brightness level of the plaque area is equal to or greater than a first critical value or less than a second critical value that is less than the first critical value, and the risk of plaque is determined to be low when the brightness level of the plaque area is less than the first critical value and equal to or greater than the second critical value and the distribution state of brightness values of the plaque area satisfies a predetermined criteria;

determining a color representing the risk of plaque, based on the brightness level of the plaque area and the distribution state of the brightness values of the plaque area by referencing a color map that correlates brightness levels and distribution states of brightness values to colors representing the risk of plaque; and

displaying the risk of plaque as the determined color.

11. The method of claim 10 , wherein the determining of the risk of plaque comprises:

determining a surface shape of the plague area;

calculating a smoothness index (SI) representing a surface uniformity of the plaque area, based on the determined surface shape; and

determining the risk of plaque based on the surface uniformity of the plaque area,

wherein the risk of plaque is determined to be low when the surface of the plaque area is uniform, and is determined to be high when the surface of the plaque area is not uniform.

12. The method of claim 11 , wherein the calculating of the SI comprises:

measuring distances from a surface of the blood vessel to the surface of the plaque area in at least one of a circumferential direction or a lengthwise direction of the blood vessel; and

calculating the SI of the plaque area based on a distribution of the measured distances.

13. The method of claim 10 , wherein the determining of the risk of plaque comprises calculating the brightness level of the plaque area and the distribution state of the brightness values based on a histogram of the brightness values of the plaque area.

14. The method of claim 13 , wherein a value representing the distribution state of the brightness values is calculated based on at least one of a median value, an average value, a minimum value, a maximum value, a distribution value, or a standard deviation calculated from the histogram.

15. The method of claim 10 , wherein the displaying of the risk of plaque comprises indicating the risk by using at least one of a graph or a numerical value.

16. The method of claim 10 , wherein the displaying of the risk of plaque comprises indicating on a first region included in the plaque area a first color corresponding to a risk of plaque in the first region, and indicating on a second region included in the plaque area a second color corresponding to a risk of plaque in the second region.

17. The method of claim 16 , wherein the displaying of the risk of plaque comprises marking an icon on a region having a higher risk between the first region and the second region.

18. The method of claim 10 , wherein the displaying of the risk of plaque comprises indicating the distribution state of the brightness values of the plaque area as a texture.