Keele Research Repository

Objective: To compare electrodiathermy with helium thermal coagulation in laparoscopic treatment of mild-to-moderate endometriosis. Design: Parallel-group randomized controlled trial. Setting: A UK endometriosis centre. Population: Non-pregnant women aged 16–50 with a clinical diagnosis of mild-to-moderate endometriosis. Methods: If mild or moderate endometriosis was confirmed at laparoscopy, women were randomized to laparoscopic treatment with electrodiathermy or helium thermal coagulator. Main outcome measures: Cyclical pain and dyspareunia (rated on 100mm visual analogue scales), and quality of life, at baseline, 6, 12, and 36 weeks following surgery; operative blood loss; surgical complications. Results: 192 women were randomized. 155 (81%) completed the primary outcome point at 12 weeks. In an intention-to-treat analysis, VAS scores for cyclical pain were significantly lower in the electrodiathermy group compared to the helium group at 12 weeks (mean difference = 9.43mm; 95% CI = 0.46, 18.40; p = 0.039) and across all timepoints (mean difference = 10.13mm; 95% CI = 3.48, 16.78; p = 0.003). A significant difference in dyspareunia also favoured electrodiathermy at 12 weeks (mean difference = 11.66mm; 95% CI 1.39, 21.93; p = 0.026). These effects were, however, smaller than the proposed minimum important difference of 18.00mm. Differences in some aspects of quality of life favoured electrodiathermy. There was no significant difference in operative blood loss (fold-change with helium as reference = 1.43; 95% CI 0.96, 2.15; p = 0.081). Conclusions: Although electrodiathermy was statistically superior to helium ablation in reducing cyclical pain and dyspareunia, these effects may be too small to be clinically significant.