The purpose of our work was to compare intraoperative and four-week post-implant dosimetry for loose and @entity2722 implants for permanent prostate implant brachytherapy. In our institute low-dose-rate (LDR) prostate brachytherapy is performed with encapsulated I-125 isotopes (seeds) using transrectal ultrasound guidance and metal needles. The SPOT PRO 3.1 (Elekta, Sweden) system is used for treatment planning. In this study the first 79 @entity1 were treated with @entity2722 ( @entity2722 ) technique, the consecutive @entity1 were treated with @entity2722 ( @entity2722 ) technique. During intraoperative planning the dose constraints were the same for both techniques. All LSs were placed inside the prostate capsule, while with @entity2722 a 2 mm margin around the prostate was allowed for seed positioning. The prescribed dose for the prostate was 145 Gy. This study investigated prostate dose coverage in 30-30 randomly selected @entity1 with @entity2722 and @entity2722 . Four weeks after the implantation native CT and MRI were done and CT/MRI image fusion was performed. The target was contoured on MRI and the plan was prepared on CT data. To assess the treatment plan dose-volume histograms were used. For the target coverage V100, V90, D90, D100, for the dose inhomogeneity V150, V200, and the dose-homogeneity index (DHI), for dose conformality the conformal index (COIN) were calculated. Intraoperative and postimplant plans were compared. The mean V100 values decreased at four-week plan for @entity2722 (97% vs. 84%) and for @entity2722 (96% vs. 80%) technique, as well. Decrease was observed for all parameters except for the DHI value. The DHI increased for @entity2722 (0.38 vs. 0.41) and for @entity2722 (0.38 vs. 0.47) technique, as well. The COIN decreased for both techniques at four-week plan ( @entity2722 : 0.63 vs. 0.57; @entity2722 : 0.67 vs. 0.50). All differences were significant except for the DHI value at @entity2722 technique. The percentage changes were not significant, except the COIN value. The dose coverage of the target decreased significantly at four-week plans for both techniques. The decrease was larger for @entity2722 technique, but the difference between techniques was not significant at this @entity1 number. The dose distribution was more homogenous, but the conformality was worse at four-week plans.

[Intraoperative and post-implant dosimetry in XXXX treated with permanent prostate implant brachytherapy].

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity2722 :: ('MESH:D009366', 'Disease') :: ['loose seed', 'SS', 'stranded seed', 'LS']
@entity1 :: (9606,Species) :: ['patients']
