Randomized, Controlled Trial of Bipolar Radiofrequency Endometrial Ablation and Balloon Endometrial Ablation

Abstract

This double-blind, randomized, controlled trial was conducted to compare the efficacy of 2 of the newer endometrial ablation devices-a hot water balloon ablation system (ThermaChoice, Gynecare; Johnson & Johnson, Somerville, NJ) and a bipolar, radiofrequency, impedance-controlled endometrial ablation system (NovaSure Endometrial Ablation Device; Novacept, Palo Alto, CA). One hundred twenty-six patients met the study criteria, which included a normal uterine cavity with no confounding diseases or conditions and a score of 150 or more on the pictorial chart depicting menorrhagia as described by Hingham et al. Participants were randomized in a 2:1 ratio, bipolar radiofrequency ablation to balloon ablation increase the information available on the bipolar technique. All surgeries were performed as same-day surgery. Randomization occurred in the operating room so that patients and investigating doctors remained unaware of the treatment group throughout the study. Follow-up examinations were conducted at 3, 6, and 12 months. Midway through the investigation, after 44 patients had been treated, a malfunction in the NovaSure generator was discovered. It occurred at some unknown point after the first 5 patients were treated. It was decided to form 2 groups for analysis. Group A consisted of all patients who entered the study, including those treated before and after the malfunction was discovered and corrected. Patients randomized after the discovery formed group B. There were 83 women treated with bipolar radiofrequency ablation and 43 women who received balloon ablation. No complications occurred in either set of patients. One woman became fearful in the operating room and dropped out of the study, refusing further treatment. Four patients in each group underwent hysterectomy. In the bipolar group, 2 patients had continued menorrhagia, and 1 each had metrorrhagia and extreme fibroid growth. Adenomyosis was diagnosed in the 2 patients with persistent heavy bleeding. Two of these 4 women were among those treated before the discovery of the malfunction, and 2 were treated after repairs were made. An additional patient in the bipolar group underwent successful hysteroscopic removal of an intrauterine fibroid type 1. All 4 women in the balloon ablation group underwent hysterectomy for treatment of continued menorrhagia. Pathology showed normal uteri in 2 and small fibroids in 2. One patient in the balloon group began using oral contraceptives after balloon ablation failed to relieve her symptoms. Results of ablation therapy are shown in Table 1. The decrease in the median duration of menstruation was significant in both groups, compared with baseline (P <0.001). There was no difference in significance between group A and group B. The number of patients who experienced amenorrhea after ablation was significantly greater in the bipolar group than the balloon group (P <0.001 at 3, 6, and 12 months). This significance persisted in analysis of group B alone. There was a significant decrease in dysmenorrhea in both groups (P = 0.001), but the difference between the bipolar group and the balloon was not significant. However, in group B at 12 months, women treated with bipolar ablation reported significantly less dysmenorrhea than those who had balloon ablation (P = 0.02). Clotting, which was a presenting symptom for nearly all patients, decreased after treatment for all women. The bipolar group experienced a significantly greater decrease in clotting compared with the bipolar group (P = 0.001). Scores on the pictorial chart decreased significantly for all patients after treatment (P = 0.001). The decrease was significantly greater in the bipolar group compared with the balloon group (P = 0.02). This was true at each stage of follow up. Patient satisfaction with treatment was greater for bipolar ablation at 3, 6, and 12 months compared with balloon ablation (P = 0.003).