Extensive tissue damage after bipolar ovarian drilling compared to monopolar electrocautery or CO2 laser

Abstract

OBJECTIVE: Ovarian drilling has been used for years in polycystic ovary syndrome (PCOS), but the amount of inflicted ovarian damage is unknown. The aim of this study is to evaluate the size of tissue damage caused by the most frequently used ovarian drilling techniques. DESIGN: Experimental prospective design. MATERIALS AND METHODS: We tested the 1) carbon dioxide (CO2) laser, 2)monopolar and 3)bipolar electrocoagulation (EC) for in vitro ‘ovarian drilling’ on 6 fresh bovine ovaries per technique.Table 1Power and length of stimulation per ovarian drilling technique (based on literature)TechniquePower (Watt)Length of stimulation (seconds)Length of needle inserted (mm)CO2 laser256Not applicableMonopolar electrocoagulation30410Bipolar electrocoagulation25Variable approx. 2-5 (auto-stop function)15 Open table in a new tab After drilling the ovaries were put in formalin before preparation by the pathologist. Each ovary was analysed separately and 3 completely evaluable lesions were used to measure the tissue damage per burn per ovary. One-way ANOVA (Bonferroni Post-Hoc test) was perfomed and a P-value of < 0.05 was considered significant. RESULTS: The CO2 laser induced a superficial cone shaped scar, the mono- and bipolar EC resulted in deeply penetrating cylinder shaped burns. Bipolar EC resulted in significantly more destruction per drilling than the other techniques.Table 2Tissue damage per lesion and assumed damage after extrapolation to regular clinical applicationTechniqueMean tissue damage per burn (mm3) (+/-SD) n=6Number of punctures normally appliedEstimated total damage (mm3) (+/-SD)CO2 laser24.0 (+/-8.5)25599 (+/-213)Monopolar electrocoagulation70.0 (+/-21.4)10700 (+/-214)Bipolar electrocoagulation287.6 (+/-65.1)∗P<0.05.102876 (+/-651)∗P<0.05.∗ P<0.05. Open table in a new tab After multipling the found damage per lesion by the usually applied number of punctures (based on literature) the bipolar EC resulted again in significantly more tissue damage. CONCLUSIONS: The amount of tissue damage caused by ovarian drilling is substantial and differs highly between the methods used. In particular bipolar EC causes extensive destruction of the ovary up to almost 3cm3 and this could have implications for the long term fertility prognosis. Given the same clinical effectiveness of the various procedures it is essential to use the lowest possible dose that works, thus the first choice should be CO2 laser or monopolar EC. In conclusion, bipolar EC causes extensive ovarian tissue loss and the currently used clinical regime should not be applied.