Comparison of intraoperatively built custom linked seeds versus loose seed gun applicator technique using real-time intraoperative planning for permanent prostate brachytherapy

Int J Radiat Oncol Biol Phys. 2011 Nov 15;81(4):1010-6. doi: 10.1016/j.ijrobp.2010.06.015. Epub 2010 Oct 1.


Purpose: To report our dosimetric results using a novel push-button seed delivery system that constructs custom links of seeds intraoperatively.

Methods and materials: From 2005 to 2007, 43 patients underwent implantation using a gun applicator (GA), and from 2007 to 2008, 48 patients underwent implantation with a novel technique allowing creation of intraoperatively built custom links of seeds (IBCL). Specific endpoint analyses were prostate D90% (pD90%), rV100% > 1.3 cc, and overall time under anesthesia.

Results: Final analyses included 91 patients, 43 GA and 48 IBCL. Absolute change in pD90% (ΔpD90%) between intraoperative and postoperative plans was evaluated. Using GA method, the ΔpD90% was -8.1 Gy and -12.8 Gy for I-125 and Pd-103 implants, respectively. Similarly, the IBCL technique resulted in a ΔpD90% of -8.7 Gy and -9.8 Gy for I-125 and Pd-103 implants, respectively. No statistically significant difference in ΔpD90% was found comparing methods. The GA method had two intraoperative and 10 postoperative rV100% >1.3 cc. For IBCL, five intraoperative and eight postoperative plans had rV100% >1.3 cc. For GA, the mean time under anesthesia was 75 min and 87 min for Pd-103 and I-125 implants, respectively. For IBCL, the mean time was 86 and 98 min for Pd-103 and I-125. There was a statistical difference between the methods when comparing mean time under anesthesia.

Conclusions: Dosimetrically relevant endpoints were equivalent between the two methods. Currently, time under anesthesia is longer using the IBCL technique but has decreased over time. IBCL is a straightforward brachytherapy technique that can be implemented into clinical practice as an alternative to gun applicators.

Publication types

  • Comparative Study

MeSH terms

  • Aged
  • Anesthesia
  • Brachytherapy / instrumentation
  • Brachytherapy / methods*
  • Computer Systems
  • Equipment Design / methods
  • Humans
  • Intraoperative Period
  • Iodine Radioisotopes / therapeutic use
  • Male
  • Middle Aged
  • Palladium / therapeutic use
  • Prostatic Neoplasms / pathology
  • Prostatic Neoplasms / radiotherapy*
  • Prostatic Neoplasms / surgery
  • Radioisotopes / therapeutic use
  • Radiotherapy Dosage
  • Radiotherapy Planning, Computer-Assisted / methods*
  • Statistics, Nonparametric
  • Time Factors


  • Iodine Radioisotopes
  • Radioisotopes
  • Palladium