Vascular characterization using ultrasound imaging

Patent metadata

Field	Value
Publication number	US-9610061-B2
Application number	US-201213446635-A
Country	US
Kind code	B2
Filing date	Apr 13, 2012
Priority date	Apr 14, 2011
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

Ultrasound methods and/or systems provide for the motion tracking of both vessel wall motion and blood flow (e.g., with use of high frame rate ultrasound pulse echo data and speckle tracking both wall motion and flow can be tracked simultaneously).

First claim

The invention claimed is:

1. A system for vascular imaging, comprising:
one or more ultrasound transducers, wherein the one or more transducers are configured to deliver ultrasound energy to a vascular region resulting in pulse-echo data therefrom; and
processing apparatus configured to:
control the capture of pulse-echo data at a frame rate such that measured displacement of a vessel wall defining at least one portion of a blood vessel in the vascular region and measured average blood flow through the at least one portion of the blood vessel have a quasi-periodic profile over time to allow motion tracking of both the vessel wall and the blood flow simultaneously, wherein the frame rate is at least greater than 100 frames per second;
generate strain and shear strain image data for the region in which the at least one portion of the vessel is located using speckle tracking, wherein the speckle tracking comprises using multi-dimensional correlation of pulse-echo data of one or more speckle regions undergoing deformation in the region in which the at least one portion of a blood vessel is located, wherein the multi-dimensional correlation comprises determining a cross-correlation peak for the sampled pulse-echo data based on phase and magnitude gradients of the cross-correlated pulse-echo data;
simultaneously measure displacement of a vessel wall defining at least one portion of a blood vessel in the vascular region and average blood flow through the at least one portion of the blood vessel based on the strain and shear strain image data;
identify at least one vascular characteristic of the vascular region in which at least one portion of a blood vessel is located based on the strain and shear strain image data and the simultaneously measured displacement of the vessel wall defining the at least one portion of a blood vessel in the vascular region and average blood flow through the at least one portion of the blood vessel, wherein the at least one vascular characteristic comprises a structural characteristic associated with the blood vessel, wherein the structural characteristic identified comprises one or more vessel wall boundaries; and
modify, when using the speckle tracking, a characteristic of at least one of the one or more speckle regions being tracked based on the one or more vessel wall boundaries identified such that the at least one speckle region is entirely within or outside of the vessel wall.

2. The system of claim 1 , wherein the processing apparatus is operable to measure tissue property within the one or more vessel wall boundaries based on both the motion tracking motion of the vessel wall and the blood flow simultaneously.

3. The system of claim 1 , wherein the processing apparatus is operable to identify vessel wall boundaries around the entire blood vessel.

4. The system of claim 1 , wherein the processing apparatus is operable to identify one or more portions of a plaque architecture adjacent the one or more vessel wall boundaries.

5. The system of claim 1 , wherein the processing apparatus is operable to use two-dimensional correlation of sampled pulse-echo data of one or more speckle regions.

6. The system of claim 1 , wherein the processing apparatus is operable to control the determination of the cross-correlation peak by at least:
coarsely searching the magnitude of the sampled pulse-echo data in a lateral and axial direction to locate a vicinity of the cross-correlation peak within the cross-correlated sampled pulse-echo data;
determining, within the vicinity of the cross-correlation peak, at least two opposing gradient vectors in proximity to the cross-correlation peak;
determining, within the vicinity of the cross-correlation peak, a zero-phase line of the cross-correlated sampled pulse-echo data; and
using the at least two opposing gradient vectors in proximity to the cross-correlation peak and the zero-phase line to estimate the cross-correlation peak.

7. The system of claim 1 , wherein system further includes a therapy system to deliver therapy to a patient based on the identification of the at least one vascular characteristic of the region in which at least one portion of a blood vessel is located.

8. The system of claim 7 , wherein the therapy system comprises a system operable to use ultrasonic energy to deliver therapy based on the identification of the at least one vascular characteristic of the region in which at least one portion of a blood vessel is located.

9. The system of claim 8 , wherein the therapy apparatus comprises at least one transducer configured to transmit and receive ultrasonic energy, wherein the at least one transducer is operable to provide ultrasonic energy to deliver therapy based on the identification of the at least one vascular characteristic of the region in which at least one portion of a blood vessel is located and the at least one transducer is operable for use in obtaining the pulse-echo data to generate image data.

10. The system of claim 1 , wherein the processing apparatus is operable to generate strain and shear strain image data for the region in which the at least one portion of the vessel is located using two-dimensional speckle tracking, wherein using two-dimensional speckle tracking comprises generating at least one of axial strain and axial shear strain image data and/or lateral strain and lateral shear strain image data.

11. The system of claim 1 , wherein the processing apparatus is operable to control providing ultrasound pulse-echo data of a region in which at least one portion of a blood vessel is located using coded excitation.

12. The system of claim 1 , wherein the processing apparatus is operable to apply a dereverberation filter to the pulse-echo data from one or more speckle regions in the blood to remove echo components in the pulse-echo data due to reflection at the vessel wall when performing speckle tracking of the pulse-echo data from the one or more speckle regions in the blood.

13. The system of claim 1 , wherein the processing apparatus is operable to modify, when using the speckle tracking, at least one of location, size, or shape based on the one or more vessel wall boundaries identified such that the at least one speckle region is entirely within or outside of the vessel wall.

14. The system of claim 13 , wherein the processing apparatus is operable to:
determine that at least one speckle region being tracked is lying partially in the blood within the vessel wall or lying partially outside of the boundaries of the vessel wall;
modify the location of the at least one speckle region based on the one or more vessel wall boundaries identified such that the speckle region is entirely within or outside of the vessel wall.

15. The system of claim 13 , wherein the processing apparatus is operable to:
determine that at least one speckle region being tracked is lying partially in the blood within the vessel wall or lying partially outside of the boundaries of the vessel wall;
modify the size or shape of the at least one speckle region based on the one or more vessel wall boundaries identified such that the speckle region is entirely within or outside of the vessel wall.

16. A system for vascular imaging, comprising:
one or more ultrasound transducers, wherein the one or more transducers are configured to deliver ultrasound energy to a vascular region resulting in pulse-echo data therefrom; and
processing apparatus configured to:
control the capture of pulse-echo data of the vascular region in which at least one portion of a blood vessel is located;
use speckle tracking of one or more speckle region

Assignees

• Ebbini Emad S
• Liu Dalong
• Wan Yayun
• Casper Andrew J
• Univ Minnesota

Inventors

• Ebbini Emad S
• Liu Dalong
• Wan Yayun
• Casper Andrew J

Classifications

• A61B8/485

  involving measuring strain or elastic properties · CPC title

• A61B8/085

  for locating body or organic structures, e.g. tumours, calculi, blood vessels, nodules · CPC title

• A61B8/486

  involving arbitrary m-mode · CPC title

• A61B8/06

  Measuring blood flow · CPC title

• A61B8/0891 Primary

  for diagnosis of blood vessels · CPC title