ENDOMETRIAL HISTOLOGY AFTER ELECTROCOAGULATION USING DIFFERENT POWER SETTINGS

Objective: To study endometrial histology after electrocoagulation in an in vitro model using 50 watts (W) and 100 W of coagulation current and determine the depth of endometrial destruction and survival, if an y, of glands beneath this zone. Design: Twenty fresh uteri of similar weights and dimensions were obtained from patients undergoing hysterec tomy for benign disease. Specimens were bivalved into anterior and pos terior walls and each wall divided in half. Endometrial electrocoagula tion was carried out with a 5-mm probe at 50 W and 100 W applied to an terior and posterior quarters of the specimen, respectively. The adjac ent untreated endometrial surfaces served as controls. Specimens were formalin-fixed, embedded in paraffin, and sections stained with hemato xylin and eosin. Main Outcome Measures: The number and morphology of t he endometrial glands were counted and classified manually for each se ction and compared between each power setting and controls. Results: H istologic examination revealed morphologically normal glands in all sp ecimens beneath the zone of destruction regardless of power setting. B oth power settings produced significant focal and diffuse glandular an d stromal destruction when compared with controls. Significant differe nces were noted in the number of normal glands after treatment with 50 W (71.33 glands +/- 76.44 [mean +/- SD]), 100 W (21.11 +/- 35.71) and untreated controls (240.16 +/- 110.81). Tissue destruction increased with increasing power, and there were significant differences in the p ercentage of morphologically normal, surviving glands between 50 W (11 .7% +/- 11.4% [mean +/- SD]) and 100 W (4.9% +/- 10.9%). Conclusion: T hese data suggest that electrocoagulation may result in a variable deg ree of endometrial destruction dependent on power. Viable glands and s troma may survive beneath the zone of destruction regardless of power. Such variations in endometrial insult in an in vitro model may explai n, in part, the variable clinical results of endometrial electrocoagul ation. The survival of glands beneath the zone of destruction in this model raises the theoretical concern for occult malignant changes and leaves open to question the exact role and mode of hormonal therapy du ring the menopause after endometrial ablation.