Automatic analysis in virtual endoscopy

• US 6,366,800 B1
• Filed: 04/23/1999
• Issued: 04/02/2002
• Est. Priority Date: 10/27/1994
• Status: Expired due to Term

• Current Assignee: Wake Forest University Health Sciences
• Original Assignee: Wake Forest University
• Inventors: Salido, Tiffany W., Hemler, Paul F., Hunt, Gordon W., Ge, Yaorong, Ahn, David K., Stelts, David R., Vining, David J.
• Primary Examiner(s): Casler, Brian L.
• Application Number:
  US09/299,061
• Time in Patent Office: 1,075 Days
• Field of Search: 600/425, 600/407, 600/410, 600/420, 600/431, 345/420, 345/419, 345/421, 345/422, 345/423, 128/920, 128/822
• US Class Current: 600/425
• CPC Class Codes: A61B 5/1076 for measuring dimensions inside body cavities, e.g. using catheters A61B3/1005 takes precedence
• CPC Class Codes: G06T 15/08 Volume rendering
• CPC Class Codes: G06T 17/00 Three dimensional [3D] modelling, e.g. data description of 3D objects
• CPC Class Codes: G06T 17/20 Finite element generation, e.g. wire-frame surface description, tesselation
• CPC Class Codes: G06T 2207/10081 Computed x-ray tomography [CT]
• CPC Class Codes: G06T 2207/20012 Locally adaptive
• CPC Class Codes: G06T 2207/30032 Colon polyp
• CPC Class Codes: G06T 2207/30064 Lung nodule
• CPC Class Codes: G06T 7/0012 Biomedical image inspection
• CPC Class Codes: G06T 7/11 Region-based segmentation
• CPC Class Codes: G06T 7/155 involving morphological operators
• CPC Class Codes: G09B 23/285 for injections, endoscopy, bronchoscopy, sigmoidscopy, insertion of contraceptive devices or enemas
• CPC Class Codes: Y02A 90/10 Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation
• CPC Class Codes: Y10S 128/92 Computer assisted medical diagnostics

Abstract

A computer system and a computer-implemented method are provided for interactively displaying a three-dimensional rendering of a structure having a lumen and for indicating regions of abnormal wall structure. A three-dimensional volume of data is formed from a series of two-dimensional images representing at least one physical property associated with the three-dimensional structure. An isosurface of a selected region of interest is created by a computer from the volume of data based on a selected value or values of a physical property representing the selected region of interest. A wireframe model of the isosurface is generated by the computer wherein the wireframe model includes a plurality of vertices. The vertices of the wireframe model are then grouped into populations of contiguous vertices having a characteristic indicating abnormal wall structure by the computer. The wireframe model is then rendered by the computer in an interactive three-dimensional display to indicate the populations of abnormal wall structure.

Claims

1. A method for automatic analysis in virtual endoscopy for interactively displaying a three-dimensional rendering of an anatomical structure having a lumen, the method comprising:

segmenting a region of interest from three-dimensional data volume obtained by a computer-controlled tomography device,

isolating a region of interest within the three-dimensional data volume prior to three-dimensional rendering,

selecting an air column as the region of interest by means of a difference in contrast between air and soft tissue, and

rendering an inside surface of an organ of interest as an outside surface of the air column corresponding to the difference in contrast between air and soft tissue.

2. The method according to claim 1, wherein the step for segmenting includes adaptively adjusting the threshold value defining the region of interest to more accurately segment specific sections of the organ during a region growing process.

3. The method according to claim 2, wherein the initial value for the adaptive threshold is −

425 HU for larger airways and −

800 HU for smaller airways.

4.The method according to claim 2, wherein the threshold value is varied between −

425 HU and −

800 HU.

4. The method according to claim 1, wherein the step for segmenting includes a three-dimensional region growing technique and an initial static threshold value.

5. The method according to claim 1, wherein the step for isolating includes modeling the isolated anatomy using a marching cubes variant algorithm.

6. A method for automatic analysis in virtual endoscopy for interactively displaying a three-dimensional rendering of an anatomical structure having a lumen, the method comprising:

introducing contrast to produce a blood-filled lumen,

segmenting a region of interest from three dimensional data volume obtained by a computer-controlled tomography device,

isolating a region of interest within the three-dimensional data volume prior to three-dimensional rendering,

selecting a blood column as the region of interest by means of a difference in contrast between blood and soft tissue, and

rendering a thin-walled soft tissue structure as an outside surface of the blood column corresponding to the difference in contrast between blood and soft tissue.

7. A method for automatic analysis in virtual endoscopy for interactively displaying a three-dimensional rendering of an anatomical structure having a lumen, the method comprising:

isolating a region of interest within the three-dimensional data volume prior to three-dimensional rendering,

selecting an air column as the region of interest by means of a difference in contrast between air and soft tissue, and

rendering an inside surface of an organ of interest as an outside surface of the air column corresponding to the difference in contrast between air and soft tissue.

8. The method according to claim 8, wherein the step for isolating includes adaptively adjusting a threshold value defining the region of interest to more accurately isolate specific sections of the organ during a region growing process.

11. The method according to claim 8, wherein the step for isolating includes a three-dimensional region growing technique and an initial static threshold value.

12. The method according to claim 8, wherein the step for isolating includes modeling the isolated anatomy using a marching cubes variant algorithm.

9. The method according to claim 9, wherein the initial value for the adaptive thresh old is about −

425 HU for larger airways and −

800 Hu for smaller airways.

10. The method according to claim 9, wherein the threshold value is varied between −

425 HU and −

800 HU.

13. A method for automatic analysis in viral endoscopy for interactively displaying a three-dimensional rendering of an anatomical structure having a lumen, the method comprising:

introducing contrast to produce a blood-filled lumen having a desired characteristic,

isolating a region of interest within the three-dimensional data volume prior to three-dimensional rendering,

selecting a blood column as the region of interest by means of a difference in contrast between blood and soft tissue, and

rendering the soft tissue structure as an outside surface of the blood column corresponding to the difference in contrast between blood and soft tissue.