A NEW TECHNIQUE FOR LAPAROSCOPIC PROPHYLACTIC OOPHOROPEXY BEFORE CRANIOSPINAL IRRADIATION IN CHILDREN WITH MEDULLOBLASTOMA

The study objective was to develop a laparoscopic technique for oophoropexy with the marking of both ovaries with titanium clips so as to be able to calculate the radiation dosage to each ovary. We propose a laparoscopic approach to oophoropexy for patients with medulloblastoma planning for craniospinal radiation. Therapeutic radiation dose exposure to the pexed and nonpexed ovaries is calculated. A surgical outpatient laparoscopic procedure for oophoropexy is described. It was determined that if the pexed ovary is moved 1 cm outside of a megavoltage radiation beam, then the dosage of radiation to the ovary is reduced to approximately 9% of the prescription dose (300 cGy), whereas if the pexed ovary is moved 2 cm outside of a megavoltage radiation beam, then the dosage of radiation is reduced to less than 5% (180 cGy). This new laparoscopic oophoropexy procedure can be performed as an outpatient before craniospinal irradiation in order to increase the chances for the preservation of gonadal steroid production and fertility in girls.