Region setting for intima media thickness measurement in an ultrasound system

• US 9,510,804 B2
• Filed: 11/12/2009
• Issued: 12/06/2016
• Est. Priority Date: 11/19/2008
• Status: Active Grant

• Current Assignee: Samsung Medison Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Medison Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Lee, Jin Yong, Shim, Jae Yoon
• Primary Examiner(s): Akar, Serkan
• Application Number:
  US12/617,166
• Publication Number:
  US 20100125202A1
• Time in Patent Office: 2,581 Days
• Field of Search: 382/100, 382/128, 382/131, 600/407, 600/427, 600/437, 600/441, 600/443, 600/449, 600/454, 600/458
• US Class Current: 1/1
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 8/0858 involving measuring tissue layers, e.g. skin, interfaces
• CPC Class Codes: G06T 2207/10132 Ultrasound image
• CPC Class Codes: G06T 2207/30101 Blood vessel; Artery; Vein; Vascular
• CPC Class Codes: G06T 7/0012 Biomedical image inspection
• CPC Class Codes: G06T 7/62 of area, perimeter, diameter or volume

Abstract

The present invention relates to an ultrasound system and a method of setting an intima-media thickness (IMT) measuring region. The ultrasound system comprises an ultrasound diagnosis unit configured to transmit ultrasound signals to a target object, receive ultrasound echo signals reflected from the target object and form an ultrasound image including a plurality of pixels based on the ultrasound echo signals, each pixel having an intensity of gray level. The ultrasound system further comprises a processor configured to compute intensities of the pixels at each row in the ultrasound image to form a first graph, compute first moving averages of the intensities for first subsets of rows in the ultrasound image by dividing the intensities by a thickness of a blood vessel to form a second graph, compute second moving averages of the intensities for second subsets of rows in the ultrasound image by dividing the intensities by a thickness of a vascular wall to form a third graph, and set an intima-media thickness (IMT) measuring region by using inflection points from the second and third graphs.

Claims

1. An ultrasound system, comprising:

an ultrasound probe configured to transmit ultrasound signals to a target object and receive ultrasound echo signals reflected from the target object; and

a processor configured to;

(i) form an ultrasound image including a plurality of pixels based on the ultrasound echo signals received by the ultrasound probe, each of the plurality of pixels having an intensity of gray level, the plurality of pixels being arranged in a plurality of rows,

(ii) compute a specific value of intensities of the pixels at each one of the rows in the ultrasound image, and form a first graph using the computed specific value of intensities of the pixels at each one of the rows,

(iii) compute a first number of pixels included within a predetermined thickness of a blood vessel and determine first subsets by sequentially shifting the specific value one by one from a first one of the rows, each first subset having the first number of specific values,

(iv) compute first moving averages of the specific values included in the respective first subsets, and form a second graph showing the computed first moving averages,

(v) compute a second number of pixels included within a predetermined thickness of a vascular wall and determine second subsets by sequentially shifting the specific value one by one from the first row, each second subset having the second number of specific values, and

(vi) compute second moving averages of the specific values included in the respective second subsets, and form a third graph showing the computed second moving averages,

(vii) set an intima-media thickness (IMT) measuring region by using inflection points from the second and third graphs; and

(viii) display the ultra sound image and the set IMT measuring region.

2. The ultrasound system of claim 1, wherein the specific value of intensities is obtained by averaging the intensities of the pixels per each row in the ultrasound image.

3. The ultrasound system of claim 1, wherein the specific value of intensities is obtained by summing the intensities of the pixels per each row.

4. The ultrasound system of claim 1, wherein the processor is further configured to detect a plurality of inflection points at which an inclination of curvatures on the second graph changes, select a first inflection point having a smallest first moving average among the inflection points in the second graph, detect a plurality of inflection points at which an inclination of curvatures on the third graph changes, select a second inflection point having a largest second moving average among the inflection points in the third graph, and set the IMT measuring region based on the first and second inflection points on the ultrasound image.

5. The ultrasound system of claim 1, wherein the first number is determined by dividing the predetermined thickness of the blood vessel by a size of the pixel.

6. The ultrasound system of claim 1, wherein the second number is determined by dividing the predetermined thickness of the vascular wall by a size of the pixel.

7. A method of setting an intima-media thickness (IMT) measuring region in an ultrasound system, comprising:

a) obtaining an ultrasound image including a plurality of pixels by an ultrasound diagnosis unit comprising an ultrasound probe within the ultrasound system, the plurality of pixels being arranged in a plurality of rows;

b) computing a specific value of intensities of the pixels at each one of the rows in the ultrasound image and forming a first graph using the computed specific value of intensities of the pixels at each one of the rows, by a processor within the ultrasound system;

c) computing a first number of pixels included within a predetermined thickness of a blood vessel and determining first subsets by sequentially shifting the specific value one by one from a first one of the rows, each first subset having the first number of specific values by the processor within the ultrasound system;

d) computing first moving averages of the specific values included in the respective first subsets, and forming a second graph showing the computed first moving averages by the processor within the ultrasound system;

e) computing a second number of pixels included within a predetermined thickness of a vascular wall and determining second subsets by sequentially shifting the specific value one by one from the first row, each second subset having the second number of specific values by the processor within the ultrasound system;

f) computing second moving averages of the specific values included in the respective second subsets, and forming a third graph showing the computed second moving averages by the processor within the ultrasound system;

g) detecting inflection points from the second and third graphs by the processor within the ultrasound system;

h) setting an intima-media thickness (IMT) measuring region by using the inflection points by the processor within the ultrasound system; and

i) displaying the ultrasound image and the set IMT measuring region.

8. The method of claim 7, wherein the step b) comprises averaging the intensities of the pixels per each row in the ultrasound image to obtain the specific value by the processor.

9. The method of claim 7, wherein the step b) comprises summing the intensities of the pixels per each row to obtain the specific value by the processor.

10. The method of claim 7, wherein the detecting step g) comprises:

g1) detecting a plurality of inflection points at which an inclination of curvatures on the second graph changes;

g2) selecting a first inflection point having a smallest first moving average among the plurality of inflection points in the second graph;

g3) detecting a plurality of inflection points at which an inclination of curvatures on the third graph changes; and

g4) selecting a second inflection point having a largest second moving average among the plurality of inflection points in the third graph.

11. The method of claim 10, wherein the setting step h) further comprises setting the IMT measuring region based on the first and second inflection points on the ultrasound image.

12. The method of claim 7, wherein the first number is determined by dividing the predetermined thickness of the blood vessel by a size of the pixel.

13. The method of claim 7, wherein the second number is determined by dividing the predetermined thickness of the vascular wall by a size of the pixel.

14. A non-transitory computer readable medium comprising instructions that, when executed by a processor, performs a method of setting intima-media thickness (IMT) measuring region by causing the processor to perform steps comprising:

a) obtaining an ultrasound image, which includes a plurality of pixels arranged in a plurality of rows;

b) computing a specific value of intensities of the pixels at each one of the rows in the ultrasound image, and forming a first graph using the computed specific value of intensities of the pixels at each one of the rows;

c) computing a first number of pixels included within a predetermined thickness of a blood vessel and determining first subsets by sequentially shifting the specific value one by one from a first one of the rows, each first subset having the first number of specific values;

d) computing first moving averages of the specific values included in the respective first subsets, and forming a second graph showing the computed first moving averages;

e) computing a second number of pixels included within a predetermined thickness of a vascular wall and determining second subsets by sequentially shifting the specific value one by one from the first row, each second subset having the second number of specific values;

f) computing second moving averages of the specific values included in the respective second subsets, and forming a third graph showing the computed second moving averages;

g) detecting inflection points from the second graph and the third graph;

h) setting an intima-media thickness (IMT) measuring region by using the inflection points; and

i) displaying the ultrasound image and the set IMT measuring region.

15. The non-transitory computer readable medium of claim 14, wherein the detecting step g) comprises:

g1) detecting a plurality of inflection points at which an inclination of curvatures on the second graph changes;

g2) selecting a first inflection point having a smallest first moving average among the plurality of inflection points in the second graph;

g3) detecting a plurality of inflection points at which an inclination of curvatures on the third graph changes; and

g4) selecting a second inflection point having a largest second moving average among the plurality of inflection points in the third graph.