Start image for spectral image iterative reconstruction

Patent metadata

Field	Value
Publication number	US-9761024-B1
Application number	US-201515518582-A
Country	US
Kind code	B1
Filing date	Oct 12, 2015
Priority date	Oct 20, 2014
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

A computing system ( 116 ) includes a reconstruction processor ( 114 ) configured to execute computer readable instructions, which cause the reconstruction processor to: receive, in electronic format, non-spectral projection data, reconstruct the non-spectral projection data to generate a non-spectral image, retrieve a non-spectral to spectral voxel value map for a basis material of interest from a set of non-spectral to spectral voxel value maps, generate a spectral iterative reconstruction start image based on the non-spectral image and the non-spectral to spectral voxel value map, and reconstruct a spectral image, in electronic format, for the material basis of interest from the non-spectral projection data with a spectral iterative reconstruction algorithm and the spectral iterative reconstruction start image.

First claim

The invention claimed is:

1. A computing system, comprising:
a reconstruction processor configured to execute computer readable instructions, which cause the reconstruction processor to:
receive, in electronic format, non-spectral projection data;
reconstruct the non-spectral projection data to generate a non-spectral image;
retrieve a non-spectral to spectral voxel value map for a basis material of interest from a set of non-spectral to spectral voxel value maps;
generate a spectral iterative reconstruction start image based on the non-spectral image and the non-spectral to spectral voxel value map; and
reconstruct a spectral image, in electronic format, for the material basis of interest from the non-spectral projection data with a spectral iterative reconstruction algorithm and the spectral iterative reconstruction start image.

2. The computing system of claim 1 , wherein the non-spectral to spectral voxel value map provides a mapping between a voxel value of the non-spectral image to a voxel value for the basis material.

3. The computing system of claim 2 , wherein the reconstruction processor identifies a voxel value of a voxel of the non-spectral image in the non-spectral to spectral voxel value map, retrieves the corresponding voxel value for the basis material, and populates a same voxel coordinate in the spectral iterative reconstruction start image with the retrieved voxel value.

4. The computing system of claim 1 , where the reconstruction processor:
receives an input indicative of at least one scan parameter of the non-spectral scan;
identifies the non-spectral to spectral voxel value map for the basis material from the set of non-spectral to spectral voxel value maps for the basis material based on the at least one scan parameter, wherein the set of non-spectral to spectral voxel value maps includes a plurality of different non-spectral to spectral voxel value maps, each for a different combination of the at least one scan parameter; and
retrieves the identified non-spectral to spectral voxel value map; and
generates the spectral iterative reconstruction start image with the retrieved the identified non-spectral to spectral voxel value map.

5. The computing system of claim 4 , wherein the at least one scan parameter includes a at least one of an x-ray tube voltage or a beam filtration of the non-spectral scan that generated the non-spectral projection data.

6. The computing system of claim 4 , wherein the non-spectral image includes voxels having values indicative of an object or subject, and the reconstruction processor:
receives an input indicative of at least one of an x-ray tube voltage or a beam filtration of the at least one scan parameter and a characteristic of the object or the subject;
identifies the non-spectral to spectral voxel value map for the basis material from the set of non-spectral to spectral voxel value maps for the basis material based on the at least one scan parameter and the characteristic, wherein the set of non-spectral to spectral voxel value maps includes a plurality of different non-spectral to spectral voxel value maps, each for a different combination of the at least one scan parameter and the characteristic; and
retrieves the identified non-spectral to spectral voxel value map; and
generates the spectral iterative reconstruction start image with the retrieved the identified non-spectral to spectral voxel value map.

7. The computing system of claim 6 , wherein the characteristic includes at least one of a size or a region of interest of the object or subject.

8. The computing system of claim 1 , wherein the reconstruction processor:
receives the set of non-spectral to spectral voxel value maps; and
stores the set of non-spectral to spectral voxel value maps, wherein each voxel value pair of a non-spectral voxel value and a spectral voxel value includes a voxel value of a preselected training set of non-spectral images and a corresponding value of a preselected training set of spectral images for the basis material.

9. The computing system of claim 1 , wherein the set of non-spectral to spectral voxel value map is included in at least one of a look-up table or a polynomial.

10. The computing system of claim 1 , wherein the basis material of interest includes at least one of a photo-electric basis material, a Compton scatter basis material, an iodine basis material, a virtual non contrast basis material, bone, or soft tissue.

11. A method, comprising:
receiving, in electronic format, non-spectral projection data from a scan;
reconstructing the non-spectral projection data to generate a non-spectral image;
retrieving a non-spectral to spectral voxel value map for a basis material of interest from a set of non-spectral to spectral voxel value maps;
generating a spectral iterative reconstruction start image based on the non-spectral image and the non-spectral to spectral voxel value map; and
reconstructing a spectral image, in electronic format, for the material basis of interest from the non-spectral projection data with a spectral iterative reconstruction algorithm and the spectral iterative reconstruction start image.

12. The method of claim 11 , wherein the non-spectral to spectral voxel value map provides a mapping between a voxel value of the non-spectral image to a voxel value for the basis material.

13. The method of claim 12 , wherein the reconstruction processor identifies a voxel value of a voxel of the non-spectral image in the non-spectral to spectral voxel value map, retrieves the corresponding voxel value for the basis material, and populates a same voxel coordinate in the spectral iterative reconstruction start image with the retrieved voxel value.

14. The method of claim 11 , further comprising:
receiving an input indicative of at least one of an x-ray tube voltage or a beam filtration of the non-spectral scan that generated the non-spectral projection data;
identifying the non-spectral to spectral voxel value map for the basis material from the set of non-spectral to spectral voxel value maps for the basis material based on the at least one of x-ray tube voltage or the beam filtration, wherein the set of non-spectral to spectral voxel value maps includes a plurality of different non-spectral to spectral voxel value maps, each for a different combination of the at least one of x-ray tube voltage or the beam filtration; and
retrieving the identified non-spectral to spectral voxel value map; and
generating the spectral iterative reconstruction start image with the retrieved identified non-spectral to spectral voxel value map.

15. The method of claim 11 , wherein the non-spectral image includes voxels having values indicative of an object or subject, and further comprising:
receiving an input indicative of at least one of an x-ray tube voltage or a beam filtration of the non-spectral scan that generated the non-spectral projection data and a characteristic of the object or the subject;
identifying the non-spectral to spectral voxel value map for the basis material from the set of non-spectral to spectral voxel value maps for the basis material based on the at least one of x-ray tube voltage or the beam filtration and the characteristic, wherein the set of non-spectral to spectral voxel value maps includes a plurality of different non-spectral to spectral voxel value maps, each for a different combination of the at least one of x-ray tube voltage or the beam filtration and the characteristic; and
retrieving the identified non-spectral to spectral voxel value map; and
generating the spectral iterative reconstruction start image with

Assignees

• Koninklijke Philips Nv

Inventors

• Proksa Roland
• Koehler Thomas

Classifications

• G06T12/20 Primary

  Inverse problem, i.e. transformations from projection space into object space · CPC title

• G06T11/006 Primary

  Physics · mapped topic

• G06T2211/408

  Dual energy · CPC title

• G06T2211/424

  Iterative · CPC title

• A61B6/5205

  involving processing of raw data to produce diagnostic data · CPC title