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

The study objective was to develop a laparoscopic technique for oophor opexy 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 la paroscopic approach to oophoropexy for patients with medulloblastoma p lanning for craniospinal radiation. Therapeutic radiation dose exposur e to the pexed and nonpexed ovaries is calculated. A surgical outpatie nt laparoscopic procedure for oophoropexy is described. It was determi ned that if the pexed ovary is moved 1 cm outside of a megavoltage rad iation beam, then the dosage of radiation to the ovary is reduced to a pproximately 9% of the prescription dose (300 cGy), whereas if the pex ed ovary is moved 2 cm outside of a megavoltage radiation beam, then t he dosage of radiation is reduced to less than 5% (180 cGy). This new laparoscopic oophoropexy procedure can be performed as an outpatient b efore craniospinal irradiation in order to increase the chances for th e preservation of gonadal steroid production and fertility in girls.