Effects of pelvic rotation and needle angle on pubic arch interference during transperineal prostate implants.

Purpose: Pubic arch interference due to an enlarged prostate gland or a narrow pubic arch is often a limiting factor in adequate prostate coverage during transperineal brachytherapy. The purpose of this study was to evaluate the effects of both pelvic rotation and needle angles on pubic arch interference using CT-based 3-D information.

Methods And Materials: Seven patients had CT imaging in both supine and lithotomy positions and 3-D treatment planning was performed with three needle angles (20 downward, 0, 20 upward).