Crister Ceberg
Professor
A note on the interpretation of the gamma evaluation index
Författare
Summary, in English
The gamma evaluation method has become the gold standard for the comparison between measured and calculated absorbed dose distributions. However, test criteria and failure rate tolerance levels have hitherto normally been based on empirical evidence, rather than rigorous statistical analysis. In this work, it is proposed that the gamma-evaluation method could be reinterpreted such that the absorbed dose difference and distance-to-agreement criteria are replaced by the standard deviations of the associated uncertainties. By comparison between absorbed dose calculations and simulated measurements for clinically realistic test cases in 1D and 2D, it is then shown that the resulting squared gamma distribution follows a chi-squared distribution with one degree of freedom. This result can be used to test the statistical significance of measured deviations, and to determine proper failure rate tolerance levels in clinical radiotherapy quality control.
Avdelning/ar
- Medicinsk strålningsfysik, Lund
Publiceringsår
2013
Språk
Engelska
Sidor
012082-012082
Publikation/Tidskrift/Serie
7th International Conference on 3D Radiation Dosimetry (IC3DDose)
Volym
444
Länkar
Dokumenttyp
Konferensbidrag
Förlag
IOP Publishing
Ämne
- Radiology, Nuclear Medicine and Medical Imaging
Conference name
7th International Conference on 3D Radiation Dosimetry (IC3DDose)
Conference date
2012-11-04 - 2012-11-08
Conference place
Sydney, Australia
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1742-6596
- ISSN: 1742-6588