Displaying three-dimensional medical images

• US 20020172409A1
• Filed: 05/18/2001
• Published: 11/21/2002
• Est. Priority Date: 05/18/2001
• Status: Abandoned Application

• Current Assignee: TeraRecon Inc. (Fortive Corp.)
• Original Assignee: TeraRecon Inc. (Fortive Corp.)
• Inventors: Takahashi, Kazuo, Saito, Motoaki
• Application Number:
  US09/860,965
• Publication Number:
  US 20020172409A1
• Time in Patent Office: Days
• US Class Current: 382/132
• CPC Class Codes: G06T 15/08 Volume rendering

Abstract

Multiple objects having the same physical property within a subject are displayed as distinct three-dimensional images. Projection data obtained by scanning the subject with electromagnetic radiation are used to create a spatial distribution of absorption values for the subject which is displayed as an image on an image display unit. Particular spatial regions within the image are defined as objects, with each object comprising a set of voxels. A density, gradient and color for an object are determined based on properties input through the a series of control panels on the image display unit. Each object is associated with one of the control panels. A relationship between degrees of opacity and values for the voxels in an object is defined in the control panel for the object and used to determine the density. The control panels also allow one or more of the objects to be selected for display. The density, gradient and color for the objects are stored in a memory. A volume rendering process uses the memory to create the three-dimensional images.

Claims

1. An apparatus for displaying three-dimensional medical images of a subject comprising:

an auxiliary display screen;

means for defining properties of one or more objects included in the subject comprising;

means for selecting an object for display;

means for defining a spatial region for an object using the auxiliary display screen;

means for defining a function representing a relation between opacity and a voxel-value for an object; and

means for assigning a color to an object;

means for mapping a voxel-density, a voxel-gradient, and a voxel-color onto a memory for each object selected for display, the voxel-density being calculated from the voxel-value and the function; and

means for volume rendering using the voxel-density, voxel-gradient and voxel-color in the memory to create a three-dimensional image for display.

2. The three-dimensional medical display apparatus according to claim 1, further comprising:

means for replacing a part of a first object with a second object by assigning the opacity and color of the second object to the part of the first object, the part of the first object being defined by where the first and second objects overlap in space.

3. The three-dimensional medical display apparatus according to claim 1, further comprising:

means for changing a size for a particular object and to move a location of the particular object with relation to other objects.

4. The three-dimensional medical display apparatus according to claim 2, further comprising:

means for changing a size for a particular object and to move a location of the particular object with relation to other objects.

5. A method for displaying three-dimensional medical images of a subject comprising:

obtaining properties for an object included in the subject, the object comprising a set of voxels and the properties comprising a selection indicator, a spatial region, color information, and a first function representing a relation between a degree of opacity and values for the set of voxels; and

if the selection indicator indicates the object is selected for display, creating a three-dimensional image of the object comprising;

calculating a density for each of the set of voxels using the first function;

calculating a gradient for each of the set of voxels based on adjacent voxels;

determining a color for each of the set of voxels;

mapping the density, gradient, and color for the set of voxels onto a memory; and

performing volume rendering on the density, gradient, and color in the memory.

6. The method according to claim 5 further comprising:

displaying a part of a first object with the opacity and color of a subset of voxels for a second object, the subset being defined by where the first and second objects overlap in space.

7. The method according to claim 6 further comprising:

determining whether to replace the part of the first object using priorities assigned to the first and second objects.

8. The method according to claim 5 further comprising:

changing a size for a particular object and moving a location of the particular object with relation to other objects.

9. The method according to claim 5 further comprising:

obtaining a second function representing a relation between the color information and values for the set of voxels, wherein the color of each of the set of voxels is determined using the second function.

10. A computer-readable medium having executable instructions for performing a method comprising:

obtaining properties for an object included in the subject, the object comprising a set of voxels and the properties comprising a s election indicator, a spatial region, color, and a first function representing a relation between a degree of opacity and values for the set of voxels; and

if the selection indicator indicates the object is selected for display, creating a three-dimensional image of the object comprising;

calculating a density for each of the set of voxels using the first function;

calculating a gradient for each of the set of voxels based on adjacent voxels;

determining a color for each of the set of voxels;

mapping the density, gradient, and color for the set of voxels onto a memory; and

performing volume rendering on the density, gradient, and color in the memory.

11. The computer-readable medium according to claim 10 having further executable instructions comprising:

displaying a part of a first object with the opacity and color of a subset of voxels for a second object, the subset being defined by where the first and second objects overlap in space.

12. The computer-readable medium according to claim 11 having further executable instructions comprising:

determining whether to replace the part of the first object using priorities assigned to the first and second objects.

13. The computer-readable medium according to claim 10 having further executable instructions comprising:

changing a size for a particular object and moving a location of the particular object with relation to other objects.

14. The computer-readable medium according to claim 10 having further executable instructions comprising:

obtaining a second function representing a relation between the color information and values for the set of voxels, wherein the color of each of the set of voxels is determined using the second function.

16. The computer system of claim 15, wherein the image process further causes the processor to obtain a selection indicator for the object and to only create the three-dimensional image when the selection indicator indicates that the object is selected.

17. The computer system of claim 15, wherein the image process further causes the processor to obtain a function representing relation between a degree of opacity and values for the set of voxels in the object and to calculate the density by applying the function to the set of voxels.

19. The computer system of claim 15, wherein the image process further causes the processor to determine whether to replace the part of the first object using priorities assigned to the first and second objects.

20. The computer system of claim 15, wherein the image process further causes the processor to change a size for a particular object and move a location of the particular object with relation to other objects.

15. A computer system comprising:

a processor;

a memory coupled to the processor through a bus; and

an image process executed from the memory to cause the processor to map to the memory a density, gradient and a color for each of a set of voxels representing an object in a subject and to create a three-dimensional image of the object by performing volume rendering on the density, gradient, and color in the memory.

18. The computer system of clam 15, wherein image process further causes the processor to display a part of a first object with the opacity and color of a subset of voxels for a second object, the subset being defined by where the first and second objects overlap in space.