Ultrasound-Guided Interventional Therapy for Recurrent Ovarian Chocolate Cysts

Abstract

The aim of this study was to determine the effectiveness of ultrasound-guided interventional therapy in the treatment of postoperative recurrent chocolate cysts. The 198 patients enrolled in this study were divided into three groups. In group 1, the saline washing group, the cavity of the cyst was washed thoroughly with warm saline. In group 2, the ethanol short-time retention group, after washing with saline, the cyst was injected with 95% ethanol with a volume of half of the fluid aspirated from the cyst. Ten minutes later, the rest of the ethanol was aspirated. In group 3, the ethanol retention group, the procedures were the same as with the ethanol short-time retention group, except that 95% of the ethanol was retained in the cyst. An ultrasound examination was performed in the third, sixth and 12th months after therapy. The chocolate cyst cure rate was significantly higher in the ethanol retention group (96%, 66/69) than in the ethanol short-time retention group (82%, 56/68) and no case was cured in the first group (saline washing). We conclude that ultrasound-guided injection and 95% ethanol retention are an effective therapy for the treatment of postoperative recurrent chocolate cysts.

Introduction

Ovarian chocolate cyst is a common hormone-dependent and refractory gynaecologic disease. Its incidence has risen in recent years, now reaching 3%–10% in woman of childbearing age. The main clinical symptoms are a progressive increase in dysmenorrhoeal (40%–60%), menstrual abnormalities and infertility (40%).

Traditional medical treatments for chocolate cysts, such as gestrinone or mifepristone, act through the induction of artificial menopause (Vercellini et al. 2009). Medical treatment is able to reduce the size of chocolate cysts but not completely remove ectopic endometrium. Conventional surgical treatment has the disadvantage of producing large wounds and, most importantly, contributing to a high recurrence rate (25%–40%) due to the extensive adhesions around the cysts (Le 2005). Vercellini et al. (1992) reported a recurrence rate of 80%–100% in patients who underwent laparoscopic drainage of endometriomas.

Ultrasound-guided interventional therapies have been used in the treatment of ovarian chocolate cysts for 20 years in clinical practice. The recurrence rates associated with this method have been reported to be between 10% and 98%. The wide range in the reported rate is due to variation among therapeutic modalities and a lack of a standard of care (Chan et al., 2003, Hsieh et al., 2009, Messalli et al., 2003, Kafali et al., 2003 Chang et al., 1997, Aboulghar et al., 1991, Giorlandino et al., 1993, Zanetta and Lissoni, 1995, Troiano and Taylor, 1998). He et al. reported a 66% cure rate in 50 ovarian chocolate cyst patients who underwent ultrasound-guided ethanol injection. In the study, 25% of the injected volume was evacuated and medical ethanol was kept within the cysts for 10 min (He and Tang 2001). Koike et al. (2002) performed ultrasound-guided interventional therapy. In a study of 45 patients with chocolate cysts, the researchers injected 50% ethanol and kept the ethanol in the cysts for 5 min. After treatment, the recurrence rate was 13.3%. Li et al. (2004) treated 12 cases of ovarian chocolate cysts with a similar approach in which they injected ethanol into the cysts and evacuated 10%–20% of the volume. After 5–10 min, the ethanol was aspirated. The authors performed the procedure up to four times and then finally injected 5–20 mL of ethanol into the cysts and did not aspirate the final ethanol added to the cysts. In these cases, the cure rate was 80%, though this study was limited by a small sample size.

Our study was designed to determine if a novel ultrasound-guided interventional therapy has a higher cure rate compared with other ultrasound-guided interventional therapies used to treat chocolate cysts. In this study, ethanol injection dosage was increased compared with previous studies but the ethanol was not aspirated from the cysts. The benefits of this procedure are preservation of ovarian function, minimal invasion, higher cure rates and lower recurrence rate.