Inverse treatment planning for an electronic brachytherapy system delivering anisotropic radiation therapy

An inverse radiation treatment planning algorithm for Sensus Healthcare's Sculptura(TM) electronic brachytherapy system has been designed. The algorithm makes use of simulated annealing to optimize the conformation number (CN) of the treatment plan. The highly anisotropic dose distributions produced by the Sculptura(TM) x-ray source empower the inverse treatment planning algorithm to achieve highly conformal treatment plans for a wide range of prescribed planning target volumes. Over a set of 10 datasets the algorithm achieved an average CN of 0.79 0.08 and an average gamma passing rate of 0.90 0.10 at 5%/5 mm. A regularization term that encouraged short treatment plans was used, and it was found that the total treatment time could be reduced by 20% with only a nominal reduction in the CN and gamma passing rate. It was also found that downsampling the voxelized volume (from 320(3) to 64(3) voxels) prior to optimization resulted in a 150x speedup in the optimization time (from 2 + minutes to < 1 s) without affecting the quality of the treatment plan.

Automated summary

The inverse radiation treatment planning algorithm is designed for Sensus Healthcare's Sculptura(TM) electronic brachytherapy system, utilizing simulated annealing to optimize the conformation number (CN). The algorithm achieved high conformal treatment plans with an average CN of 0.79 ± 0.08 and an average gamma passing rate of 0.90 ± 0.10 at 5%/5 mm, demonstrating the potential to reduce treatment time by 20% without sacrificing plan quality. Additionally, downsampling the voxelized volume resulted in a significant speedup of the optimization process without impacting plan quality.