Comparison of graphical optimization and inverse planning simulated annealing for brachytherapy of cervix cancers / 中华放射医学与防护杂志

ABSTRACT

Objective To compare the differences and characteristics of the dose distribution of the two optimization methods in the three dimensional brachytherapy,and provide the basis for clinieal treatment.Methods Excel 2007 was used to generate random number.And a total of 21 patients of cervical cancer were selected from those who have completed the treatment.Inverse simulated annealing optimization (IPSA) plans were designed for graphical optimization (GO) plans.The dose volume histogram (DVH) parameters of the targets (V100％,V150％) and the organs (D1 cm3,D2cm3) of the two methods were analyzed.Results The targets dose of both plans could meet the prescription requirements.There was no statistically significant difference in the dose parameters of all targets (P ＞ 0.05).The closes of D1 cm3 and D2cm3 in the bladder of IPSA plan were significantly lower than that of the GO plan (t =3.596,3.490,P ＜ 0.05).There was no statistically significant difference in the dose parameters of rectum (P ＞ 0.05).Conclusions For cervix brachytherapy,the GO and IPSA have no effect on targets dose,but IPSA optimization can reduce the maximum dose of bladder.