Reduction of Systematic Error in Radiopharmaceutical Activity by Entropy Based Mutual Information

Palliyakarany T. K. Kumar, Toshikazu Takeda

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DOI: 10.4236/wjnst.2012.21001                

Abstract

The quality of the radiation dose depends upon the gamma count rate of the radionuclide used. Any reduction in error in the count rate is reflected in the reduction in error in the activity and consequently on the quality of dose. All the efforts so far have been directed only to minimize the random errors in count rate by repetition. In the absence of probability distribution for the systematic errors, we propose to minimize these errors by estimating the upper and lower limits by the technique of determinant in equalities developed by us. Using the algorithm we have developed based on the tech- nique of determinant inequalities and the concept of maximization of mutual information (MI), we show how to process element by element of the covariance matrix to minimize the correlated systematic errors in the count rate of ^{113 m}In. The element wise processing of covariance matrix is so unique by our technique that it gives experimentalists enough maneuverability to mitigate different factors causing systematic errors in the count rate and consequently the activity of ^{113 m}In.

Keywords

Random and Systematic Errors; Covariance Matrix; Limits for Correlated Elements by Determinant Inequalities; Mutual Information; Reduction of Systematic Errors by Maximizing Mutual Information

Conflicts of Interest

The authors declare no conflicts of interest.

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