Fletcher-Suit-Delclos gynecologic applicator: evaluation of a new instrument.

A new instrument has been added to the Fletcher-Suit-Delclos group of gynecologic applicators. The colpostats can be used as mini-ovoids, but by adding a shielded cap, the instrument has the configuration of the original preload Fletcher colpostat. Dosimetric studies show that this applicator produced transmission ratios (the fraction of radiation transmitted through the tungsten shield) and isodose curves similar to the bladder trigone and anterior rectal wall of 10-25%. With the shield-containing cap removed, the mini-ovoid provides little reduction in dose to those areas and should be used with caution.