Study objective: To demonstrate the feasibility of management of large endometrioma laparoscopically.

Design: Stepwise demonstration with narrated video footage of the laparoscopic 2-step procedure starting with alcohol sclerotherapy of the large endometrioma followed by CO₂ laser ablation and 6-month follow-up.

Setting: The debate surrounding the best approach for the management of large endometriomas has been ongoing. Cystectomy especially when treating large endometriomas has been shown to decrease ovarian reserve proportionally to the endometrioma's size.^2,4 This is why 2-step approaches have been considered to preserve the ovarian reserve.^1,3 We present the case of a 22-year-old nulliparous woman who has primary severe dysmenorrhea resistant to medical treatment. Magnetic resonance imaging shows uterine adenomyosis and a 10 cm large endometrioma of the left ovary and no signs of deep infiltrative endometriosis. She has a desire for pregnancy in the distant future.

Intervention: The first step is the laparoscopic ethanol sclerotherapy. After emptying and rinsing the endometrioma's cavity through a 5 mm suction cannula, it is then filled with ethanol through a 14 French Foley catheter to avoid any overflow.^5,6 After a time exposure of 10 minutes, the ethanol is withdrawn and the cavity rinsed (Figure 2). The second step of the surgery is performed 12 weeks later (Figure 3). Using CO₂ laser, the untreated portion of the inner wall of the remaining endometrioma is vaporized along with remaining superficial endometriosis lesions (Figure 1).

Conclusion: Laparoscopy sclerotherapy combined to CO₂ laser ablation is a feasible technique for the management of a large endometrioma. Further research is still required to evaluate the benefit of a 2-step surgery approach over standard cystectomy and to understand the long-term effects of ethanol-induced ovarian fibrosis.