Systems and methods for constructing images

• US 8,135,198 B2
• Filed: 08/06/2008
• Issued: 03/13/2012
• Est. Priority Date: 08/08/2007
• Status: Active Grant

• Current Assignee: Elekta Ltd. (Elekta AB)
• Original Assignee: Resonant Medical Incorporated (Elekta AB)
• Inventors: Lachaine, Martin, Scheipers, Ulrich, Donovan, Michael
• Primary Examiner(s): Perkey, W. B.
• Application Number:
  US12/186,801
• Publication Number:
  US 20090041323A1
• Time in Patent Office: 1,315 Days
• Field of Search: 382/128, 382/131
• US Class Current: 382/131
• CPC Class Codes: A61B 8/483 involving the acquisition of a 3D volume of data
• CPC Class Codes: G06T 15/08 Volume rendering
• CPC Class Codes: G06T 3/4007 based on interpolation, e.g. bilinear interpolation image demosaicing G06T3/4015; edge-driven or edge-based scaling G06T3/403

Abstract

Techniques and systems for constructing a three-dimensional representations of anatomical structures from a series of images of the structure include creating interpolated images between actual images and defining voxels based on pixel values of the actual and interpolated images. A three-dimensional representation of the structure may be constructed based on the voxels.

Claims

1. A method of constructing a voxel-based representation of an anatomical structure, the method comprising the steps of:

(a) acquiring a plurality of images of the anatomical structure;

(b) defining a space of voxels, each having a size, with respect to the acquired images;

(c) determining distances between the acquired images;

(d) based on the determined distances and the voxel size, creating a sufficient number of interpolated images between the acquired images such that a sufficent number of voxels between images are intersected by pixels from at least one acquired image or interpolated image; and

(e) assigning values to the voxels based on the intersecting pixels.

2. The method of claim 1 wherein the images comprise or consist of two-dimensional ultrasound images.

3. The method of claim 1 wherein the images comprise or consist of one-dimensional image lines.

4. The method of claim 1 further comprising defining a reference coordinate system about the anatomical structure and aligning the reference coordinate system to the voxel space and the acquired images.

5. The method of claim 4 wherein the distance between two images is the maximum distance between corresponding corner points of the two images based on the reference coordinate system.

6. The method of claim 1 wherein the voxel size corresponds to an average length of the voxel along each of three dimensions.

7. The method of claim 1 further comprising removing one or more of the acquired images such that all voxels are intersected by no more than one image.

8. The method of claim 1 further comprising creating two or more sub-images from each image in the series and performing steps (c) through (e) using the sub-images.

9. The method of claim 1 wherein the sufficient number of voxels comprises all of the defined voxels.

10. The method of claim 1 further comprising:

(i) defining a reference coordinate system about the anatomical structure;

(ii) determining a plurality of intersection lines between a first plane substantially orthogonal to a first axis of the reference coordinate system and the acquired images and the interpolated images intersecting each voxel;

(iii) determining a number of points along each intersection line;

(iv) defining an array for each intersection line having a number of positions based on the number of points in its respective intersection line;

(v) placing pixel values from each point along each intersection line into the respective position of the respective array;

(vi) repeating steps (ii) through (v) for subsequent planes along the first axis; and

(vii) constructing a three-dimensional representation of the anatomical structure based on the pixel values stored in the arrays.

11. A method of constructing a three-dimensional representation of an anatomical structure from a series of images, the method comprising:

(a) defining a reference coordinate system about the anatomical structure;

(b) determining a plurality of intersection lines between a first plane substantially orthogonal to a first axis of the reference coordinate system and an image from the series of images;

(c) for each intersection line, defining an array having a number of positions based on a length of the intersection line;

(d) placing pixel values from each position of each intersection line into respective positions in the corresponding arrays;

(e) repeating steps (b) through (d) for additional planes along the first axis; and

(f) constructing a three-dimensional representation of the anatomical structure based on the pixel values stored in the arrays.

12. The method of claim 11 wherein the series of images comprises two-dimensional ultrasound images.

13. The method of claim 11 further comprising (i) calculating an average pixel value for each intersection line based on stored values of pixels thereon and (ii) defining voxels intersected by the intersection line based on the average pixel value.

14. A system for constructing a voxel-based representation of an anatomical structure, the system comprising:

(a) a register for storing a plurality of images of the anatomical structure;

(b) a processor configured to (i) define a space of voxels, each having a size, with respect to the anatomical structure, (ii) determine a distance between the images, (iii) based on the determined distances and the voxel size, create a sufficient number of interpolated images between the stored images such that a sufficient number of voxels between the images are intersected by pixels from at least one image or interpolated image, and (iv) assign values to the voxels based on the intersecting pixels; and

(c) a display for displaying a three-dimensional representation of the anatomical structure constructed from voxels.

15. The system of claim 14 wherein the plurality of images comprises two-dimensional ultrasound images.

16. The system of claim 14 wherein the plurality of images comprises one-dimensional image lines.

17. The system of claim 14 wherein the plurality of images are registered to a reference coordinate system about the anatomical structure, the reference coordinate system establishing relative physical locations of the voxels.

18. The system of claim 17 wherein the voxel size corresponds to an average length of the voxel along each of three dimensions in the reference coordinate system.

19. The system of claim 14 wherein the processor is further configured to remove one or more of the plurality of images such that all voxels are intersected by at no more than one image.

20. The system of claim 14 wherein the processor is further configured to create two or more sub-images from each image in the series and performing processing steps (iii) through (v) using the sub-images.