Device and method for correcting sensitivity of a gamma camera
AssigneeKabushiki Kaisha Toshiba
InventorTakashi Ichihara
Life of this patent
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Abstract
A gamma camera sensitivity correction device and method which utilizes the fact that the collimator's characteristic correction coefficients do not change with time, wherein first of all the collimator's characteristic sensitivity data are found, and then freshly collected detector characteristic uniformity data are found with the collimator removed. From the collimator's characteristic sensitivity data and detector's characteristic uniformity data, uniformity data in the condition that the collimator is mounted on the detector are derived. Then, correction coefficients are determined based on these derived uniformity data. In this way, the uniformity correction matrix for sensitivity correction can be found with a small radiation source in a short time.
Claims12
Gamma camera sensitivity correction device capable of sensitivity correction of a gamma camera including a collimator and a light detector, wherein radiation from a radioisotope administered to a subject is detected and an image of the accumulation of the radioisotope in said subject is obtained, comprising:
- first calculating means for obtaining collimator characteristic sensitivity data that are characteristic of said collimator;
- means for freshly collecting uniformity data that are characteristic of the detector in the condition with said collimator removed;
- means for deriving uniformity data in the condition in which the collimator is fitted on said detector, based on the freshly collected uniformity data, from said collecting means, that are characteristic of the detector, and on the collimator characteristic sensitivity data from said first calculating means;
- and
- second calculating means for determining uniformity correction coefficients for radioisotope accumulation image correction, based on the uniformity data from said derivation means.
A method for correcting sensitivity of a gamma camera including a collimator and a light detector, wherein radiation from a radioisotope administered to a subject is detected and an image of the accumulation of the radioisotope in said subject is obtained, comprising:
- a first step of obtaining collimator characteristic sensitivity data that are characteristic of said collimator;
- a second step of freshly collecting uniformity data that are characteristic of the detector in the condition with said collimator removed;
- a third step of deriving uniformity data in the condition in which the collimator is fitted on said detector, based on the freshly collected uniformity data, that are characteristic of the detector, and on the collimator characteristic sensitivity data from said first steps;
- and
- a fourth step of determining uniformity correction coefficients for radioisotope accumulation image correction, based on the uniformity data from said third step.
Dependencies are inferred from the claim text.