Patent ID: 7474727
Filing Date: 2009-01-06
Classification: A61B,G01N

Abstract:
1. A method for dynamic computed tomography wherein a contrast agent is injected into a patient, and a region of interest of the patient where the contrast agent is flowing is then scanned with a computed tomography machine, the computed tomography machine having a ray source and a ray detector, at least the ray source rotating relative to said region of interest of the patient, comprising the steps of: at a first rotational position of the ray source for a first rotation at a first time point a first image is obtained, and at said first rotational position for at least another rotation at a second time point a second image is obtained, the first and second images being different from one another in view of the flowing contrast agent; for at least another rotational position of the ray source for said first rotation at a third time point a third image is obtained, and at said another rotational position for said another rotation at a fourth time point a fourth image is obtained, the third and fourth images being different from one another in view of the flowing contrast agent; performing a first time interpolation for at least said first and second images at an intermediate time point between said first and second time points, and performing at least a second time interpolation for at least said third and fourth images at an intermediate time point between said third and fourth time points; using at least said first and second time interpolations, creating a reconstructed image for said first and another rotations; wherein a sampling rate for the images obtained is chosen based on a maximum frequency of dynamic changes for the reconstructed image caused by the flowing of the contrast agent under constraint of a rotational speed of the ray source; and said ray source producing a fan beam and the temporal interpolation being performed between different beams of the fan beam.