An asymmetric, posterior spacing system for use with mini-ovoids in the treatment of carcinoma of the cervix

Customized brachytherapy implants are an important component of the management of patients with carcinoma of the cervix. An asymmetric, posterior-spacing system was designed to improve the ability to deliver customized brachytherapy implants. This system attaches to standard mini- ovoids to selectively increase the distance between the ovoids and rectum, thereby reducing the radiation dose to the rectum. The posterior spacing system is used at the time of tandem and ovoid placements that require mini- ovoids. Minimal operative time is required, and no loading adjustments are needed. The system can be sterilized and re-used. Significant rectal dose reduction in the range of 10% to 25% can be achieved. This posterior spacing system has several advantages over typical packing in mini-ovoid applications: (1) Since mini-ovoids are only used in patients with narrow vaginal vaults, the posterior spacing system provides guaranteed spacing in tight surroundings; (2) The spacing system is rapid to employ, thereby minimizing anesthesia time; (3) The spacing system will not slip out of position. The asymmetric posterior spacing system is useful for patients in whom selective posterior spacing is required to reduce the radiation dose to the rectum from brachytherapy using tandem and ovoids for the treatment of carcinoma of the cervix.