| US 7,474,727 B2 | ||
| Dynamic computed tomography method and apparatus with temporal interpolation of data in perfusion studies | ||
| Pau Montes Vives, Heidelberg (Germany); and Günter Lauritsch, Erlangen (Germany) | ||
| Assigned to Siemens Aktiengesellschaft, Munich (Germany) | ||
| Filed on Oct. 12, 2006, as Appl. No. 11/581,016. | ||
| Claims priority of provisional application 60/726552, filed on Oct. 14, 2005. | ||
| Prior Publication US 2007/0092055 A1, Apr. 26, 2007 | ||
| Int. Cl. G01N 23/00 (2006.01) | ||
| U.S. Cl. 378—4 [378/8] | 14 Claims |
| 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.
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