Safety and clinical outcomes of two-session catheter-directed sclerotherapy using 99% ethanol for endometrioma

Abstract

Background: Endometrioma is a cystic lesion formed in the ovaries consisting of old menstrual blood and tissue. It often is seen in women of reproductive ages, making fertility challenging for those with an immediate or future desire for pregnancy. Current treatment options include medical treatment, laparoscopic cystectomy, drainage, and ablative techniques, but each option has its limitations. Transvaginal sclerotherapy using highly concentrated ethanol under ultrasound guidance aims to destroy endometrial tissue inside the cyst while sparing the cyst wall, protecting surrounding oocytes from damage. However, the optimal retention duration remains controversial. To increase the retention duration without leaving ethanol inside for a long term, a two-session catheter-directed sclerotherapy (CDS) 1 day apart was proposed. Therefore, the purpose of the study was to evaluate the safety and clinical outcomes of two-session CDS with 99% ethanol in patients with endometrioma. Materials and Methods: This prospective study was approved by the institutional review board with written informed consent obtained from all participants and was registered on clinicaltrial.gov. Consecutive patients with ovarian endometrioma between June 2020 and March 2023 were prospectively evaluated for two-session CDS. After successful transvaginal ultrasound-guided puncture of the endometrioma, the biopsy needle was exchanged for a 7- or 8.5-F catheter for aspiration and ethanol injection. The catheter was retained in situ for a second session the next day. Endometrioma volume was measured on ultrasound before and 1, 3, and 6 months after CDS, and volume reduction ratio (VRR) was calculated. Serum anti-Müllerian hormone (AMH) was measured before and 6 months after CDS to assess ovarian reserve. Results: Thirty-one endometriomas in 22 patients (mean age, 31.0 years; range, 19–44 years) were treated; 28 endometriomas were successfully treated with two-session CDS, while one session was incomplete in three endometriomas (3/31, 9.7%; the first session was incomplete in one patient and the second session in two patients) in three patients due to contrast medium leakage or pain. Therefore, a technical success rate of 90.3% (28/31 endometriomas) was achieved. Minor procedure-related complications developed in four patients and resolved spontaneously before discharge on the same day of the second session. No recurrence was identified during follow-up. At the 6-month follow-up, the mean endometrioma diameter decreased from 5.5 ± 1.7 cm to 1.4 ± 0.9 cm (P < 0.001), and the serum AMH level was lowered without statistical significance (1.37 ± 0.96 ng/mL vs. 1.18 ± 0.92 ng/mL; P = 0.170). VRRs at 1, 3, and 6 months after CDS were 84.3 ± 13.7%, 94.3 ± 5.8%, and 96.4 ± 4.7%, respectively. Conclusion: Two-session CDS with 99% ethanol is safe, feasible, and effective for treating endometrioma with the ovarian function well preserved.