Three‐dimensional‐printed vaginal applicators for electronic brachytherapy of endometrial cancers

PURPOSE Vaginal applicators for a novel miniature x-ray tube were developed using three-dimensional (3D) printing to be used in brachytherapy of endometrial cancers. METHODS Cylindrical vaginal applicators with various diameters, lengths, and infill percentages (IFPs) were fabricated using a 3D printer. X-ray dose distributions and depth-dose profiles were calculated using a Monte Carlo simulation. The performances of the applicators were evaluated by measuring and analyzing the dosimetric characteristics of x rays generated from the miniature x-ray tube equipped with the applicators. RESULTS Quite uniform dose distributions around the applicators were achieved by optimizing the dwell positions and the dwell times of the miniature x-ray tube inside the applicators. In addition, identical absolute dose and depth-dose profiles were obtained through the control of the IFP values even though different-sized applicators are used. CONCLUSION The presented 3D printing technique provides an efficient approach to provide vaginal applicators with optimal IFPs that allow consistent treatment time for patients of varying vaginal canal size.

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