Are dose calculations during dose optimization in brachytherapy necessary?
We consider the problem of anatomy based dose optimization in brachytherapy. A calculation method for some objective functions and their derivatives is proposed which significantly reduces the number of required operations. The optimization in some cases, ignoring a preprocessing step, is independent of the number of sampling points. The idea is that some of the objectives and their derivatives used for dose optimization do not require the explicit calculation of dose values. Dose optimization with the new modified computation method for the objectives and derivatives is, depending on the number of sampling points, up to 100 times faster than the conventional method with dose calculation.
Lahanas
M
M
Department of Medical Physics & Engineering, Strahlenklinik, Klinikum Offenbach, 63069 Offenbach, Germany. mlahanas@gmx.de
Baltas
D
D
D000465:Algorithms; D001918:Brachytherapy / Q000379:methods*; D003198:Computer Simulation; D019583:Dose Fractionation, Radiation; D006801:Humans; D008297:Male; D008954:Models, Biological; D015233:Models, Statistical; D009928:Organ Specificity; D011471:Prostatic Neoplasms / Q000532:radiotherapy; D011835:Radiation Protection / Q000379:methods*; D011874:Radiometry / Q000379:methods*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D018401:Sample Size; D012680:Sensitivity and Specificity