X-ray examination apparatus for reconstructing a three-dimensional data set from projection images

• US 20030043960A1
• Filed: 08/09/2002
• Published: 03/06/2003
• Est. Priority Date: 08/10/2001
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Koppe, Reiner, Klotz, Erhard Paul Artur, Op De Beek, Johannes Catharina Antonius
• Granted Patent: US 6,788,759 B2
• Time in Patent Office: Days
• US Class Current: 378/19
• CPC Class Codes: A61B 6/4225 using image intensifiers
• CPC Class Codes: A61B 6/466 adapted to display 3D data
• CPC Class Codes: A61B 6/583 using calibration phantoms
• CPC Class Codes: Y10S 378/901 Computer tomography program or processor

Abstract

An X-ray examination apparatus includes an X-ray source and an X-ray detector and is arranged to provide a series of projection images at respective orientations of the X-ray source (1) and the X-ray detector (2) relative to a predetermined frame of reference. The orientations of the projection images are calibrated relative to this frame of reference. A basic three-dimensional data set (23) is reconstructed from the projection images. A number of directions of observations (12₁-12₃) are calibrated relative to the same frame of reference. One or more additional X-ray images (11₁-11₃) are formed for the calibrated directions of observation, that is, preferably at successive instants in time. A dynamic series of three-dimensional data sets is formed by updating the basic three-dimensional data set by means of the additional X-ray images.

Claims

1. An X-ray examination apparatus which includes an X-ray source and an X-ray detector, the apparatus comprising:

means for forming a series of projection images at respective orientations of the X-ray source and the X-ray detector relative to a predetermined frame of reference;

means for calibrating the orientations relative to the frame of reference; and

means for reconstructing a basic three-dimensional data set from the series of projection images, wherein the positions of the X-ray source and the X-ray detector relative to the frame of reference are calibrated for one or more additional directions of observation.

2. The X-ray examination apparatus of claim 1 including means for forming one or more additional X-ray images for the one or more additional directions of observation.

3. The X-ray examination apparatus of claim 2 including means for reconstructing a dynamic series of three-dimensional data sets on the basis of the basic three-dimensional data set and respective additional X-ray images.

4. The X-ray examination apparatus of claim 3 wherein the means for reconstructing the dynamic series of three-dimensional data sets includes means for updating the basic three-dimensional data set on the basis of successive additional X-ray images.

5. The X-ray examination apparatus of claim 1 including means for moving at least one of the position of the X-ray source and the X-ray detector for such an additional direction of observation is reached as from a predetermined starting position.

6. The X-ray examination apparatus of claim 1 including means for forming the projection images at successive orientations at successive instants, and means for calibrating the successive orientations with the successive instants.

7. The X-ray examination apparatus of claim 1 including means for forming separate series of projection images for separate sets of orientations of the X-ray source and the X-ray detector relative to the frame of reference, wherein respective orientations in individual sets deviate from one another by a rotation about each time the same axis of rotation.

8. The X-ray examination apparatus of claim 7 wherein the orientations for individual sets of orientations deviate from one another by a rotation about an axis of rotation which is specific of the individual sets.

9. The X-ray examination apparatus of claim 8 wherein the respective specific axes of rotation have been rotated relative to an axis of revolution.

10. A method of X-ray examination comprising the steps of:

irradiating a subject with an x-ray source;

detecting the radiation with a detector;

forming a series of projection images at respective orientations of the X-ray source and the X-ray detector relative to a predetermined frame of reference,

calibrating the orientations relative to the frame of reference; and

reconstructing a basic three-dimensional data set from the series of projection images wherein the positions of the X-ray source and the X-ray detector relative to the frame of reference are calibrated for one or more additional directions of observation.

11. The method of X-ray examination of claim 10 including the step of forming one or more additional X-ray images for the one or more additional directions of observation.

12. The method of X-ray examination of claim 11 including the step of reconstructing a dynamic series of three-dimensional data sets on the basis of the basic three-dimensional data set and respective additional X-ray images.

13. The method of X-ray examination of claim 12 including the step of reconstructing the dynamic series of three-dimensional data sets by updating the basic three-dimensional data set on the basis of successive additional X-ray images.

14. The method of X-ray examination of claim 10 including the step of adjusting the position of at least one of the position of the X-ray source and the position of the X-ray detector for such an additional direction of observation is reached as from a predetermined starting position.

15. The method of X-ray examination of claim 10 including the steps of forming the projection images at successive orientations at successive instants and calibrating the successive orientations with the successive instants.

16. The method of X-ray examination of claim 10 including the step of forming separate series of projection images for separate sets of orientations of the X-ray source and the X-ray detector relative to the frame of reference where respective orientations in individual sets deviate from one another by a rotation about each time the same axis of rotation.

17. The method of X-ray examination of claim 16 including rotation of the orientations for individual sets of orientations deviate from one another about an axis of rotation which is specific of the individual sets.

18. The method of X-ray examination apparatus as claimed in claim 17 including rotating the respective specific axes of rotation relative to an axis of revolution.