Abstract:
:An inverse radiation treatment planning algorithm for Sensus Healthcare's SculpturaTM electronic brachytherapy system has been designed. The algorithm makes use of simulated annealing to optimize the conformation number of the treatment plan. The highly anisotropic dose distributions produced by the SculpturaTM 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 conformation number 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 conformation number and gamma passing rate. It was also found that downsampling the voxelized volume (from 3203 to 643 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.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Badali DS,Vainer Y,Ellenor CW,Mitchell CR,Fishman K,Soro N,Price R,Funk Tdoi
10.1088/1361-6560/abda9asubject
Has Abstractpub_date
2021-01-11 00:00:00eissn
0031-9155issn
1361-6560pub_type
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