Histological Assessment of Tissue Penetration Depth of Argon Beam Coagulation in Ovarian Endometriomas

Endometriosis is a chronic inflammatory disease affecting approximately 10% of women of reproductive age. Ovarian endometriomas are a common manifestation of the disease and frequently require surgical treatment. Conventional cystectomy may unintentionally remove healthy ovarian tissue, potentially reducing ovarian reserve and affecting future fertility. Tissue-preserving surgical techniques are therefore of increasing clinical interest.

Argon Beam Coagulation (ABC) is an energy-based surgical technology that allows non-contact coagulation using ionized argon gas. Although ABC is increasingly used in endometriosis surgery, limited histological evidence is available regarding the depth of tissue penetration produced by this technique.

This prospective, single-center interventional study will enroll women undergoing laparoscopic surgery for ovarian endometriomas at the University Hospital Bern. During the planned surgical procedure, Argon Beam Coagulation will be applied to the ovarian surface according to a standardized protocol. The treated tissue will subsequently be excised during the same operation and processed for histological examination.

The primary objective of the study is to quantify the histological depth of tissue penetration of Argon Beam Coagulation in ovarian tissue. Secondary objectives include evaluating the consistency of tissue penetration and generating data that may support the safe use of ABC as a tissue-preserving surgical technique in the management of ovarian endometriomas.

Inclusion criteria

• Female patients aged 18-40 years.
• Indication for surgical treatment of ovarian endometrioma based on clinical symptoms and/or imaging findings.
• Diagnosis of ovarian endometrioma ≥3 cm confirmed by preoperative imaging (ultrasound and/or MRI).
• Planned laparoscopic cystectomy.
• Written informed consent.

Exclusion criteria

• Expected lack of compliance or inability to understand the study procedures.
• Previous surgical procedures on the affected ovary.
• Recurrent ovarian endometrioma.
• Pregnancy or breastfeeding.
• Participation in another interventional clinical study that may influence study outcomes, such as anti-Müllerian hormone (AMH) levels or pregnancy.