Fast computation of the sensitivity matrix in iterative algorithms

Patent metadata

Field	Value
Publication number	US-9317942-B2
Application number	US-201113884976-A
Country	US
Kind code	B2
Filing date	Nov 2, 2011
Priority date	Nov 15, 2010
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

An image processing apparatus includes a geometric correction memory which stores a pre-calculated geometric matrix specific to an imaging apparatus. An attenuation map memory which stores an attenuation map of a subject to be imaged in the imaging apparatus. A buffer stores a plurality of lines generated by the imaging apparatus to be reconstructed. A processor reconstructs the lines into a attenuation corrected image representation of the subject using the lines from the buffer, the attenuation map, and the geometric matrix.

First claim

Having thus described the preferred embodiments, the invention is now claimed to be:

1. A image processing apparatus comprising:
a geometric correction memory which stores a pre-calculated geometric matrix specific to an imaging apparatus;
an attenuation map memory which stores an attenuation map of a subject to be imaged in the imaging apparatus;
a buffer which stores a plurality of lines generated by the imaging apparatus to be reconstructed;
a processor which reconstructs the lines into an attenuation corrected image representation of the subject using the lines from the buffer, the attenuation map, and the geometric matrix; and
wherein the geometric correction memory includes a look-up table storing pre-calculated geometric matrix values which are calculated for the imaging apparatus during manufacture and are not calculated for each patient.

2. The image processing apparatus according to claim 1 , wherein the geometric matrix represents a relationship between a first voxel and each of the voxels that all possible lines through the first voxel can intersect.

3. The image processing apparatus according to claim 1 , wherein the lines through the first voxel are stored in the buffer in list mode format and the processor reconstructs the image representation using a list-mode reconstruction algorithm.

4. The image processing apparatus according to claim 1 , wherein the imaging apparatus is a PET scanner.

5. The imaging processing apparatus according to claim 1 , further including:
a display configured to display the attenuation corrected image representation of the subject.

6. The imaging processing apparatus according to claim 1 , wherein the processor determines a boundary of negligible voxels that do not significantly contribute to a sensitivity value of a voxel and ignores all voxels outside of the boundary when calculating the sensitivity matrix for a certain voxel.

7. An image processing apparatus comprising:
a geometric correction memory configured to store a pre-calculated geometric matrix specific to an imaging apparatus;
an attenuation map memory configured to store an attenuation map of a subject to be imaged in the imaging apparatus;
a buffer configured to store a plurality of lines generated by the imaging apparatus to be reconstructed in a list mode format; and
a processor configured to reconstruct the lines into an attenuation corrected image representation of the subject using the lines from the buffer, the attenuation map, and the geometric matrix, wherein the processor is configured to reconstruct the image using a reconstruction algorithm represented by

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Assignees

• Olivier Patrick
• Koninkl Philips Nv

Inventors

• Olivier Patrick

Classifications

• G06T12/20 Primary

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

• G06T12/30 Primary

  Image post-processing, e.g. metal artefact correction · CPC title

• G06T11/006

  Physics · mapped topic

• G06T11/008 Primary

  Physics · mapped topic

• G06T2211/424

  Iterative · CPC title