Development of an endometrial ablation model in New Zealand White rabbits

OBJECTIVE: To develop an animal model for radiofrequency endometrial ablation (EA) and evaluate histopathologic outcomes of EA in New Zealand White (NZW) rabbits. STUDY DESIGN: A pilot study was conducted. A radiofrequency EA device was developed and a variety of EA settings were tested on euthanized NZW rabbits. An algorithm was developed to determine target EA parameters. Bilateral radiofrequency EA was performed via laparotomy using 5.2 mm, 6.1 mm, or 7.1 mm diameter × 100 mm bipolar probes on 10 live NZW rabbits. All rabbits were screened for endometrial cancer (EC). Rabbits were euthanized 3 weeks following EA, and histopathologic analysis of postablation hysterectomy specimens was performed. RESULTS: Bilateral radiofrequency EA was successful in rabbits that were candidates for the procedure, and uterine assessment was feasible in all rabbits. One case of EC was detected. Uterine anatomy was variable among rabbits. The optimal EA setting was 4.5 W/cm²×20 seconds, which provided consistent thermal destruction to the endometrium and inner myometrium as verified by histology. CONCLUSION: Use of a radiofrequency EA algorithm tailored to individual NZW rabbits produces consistent thermal destruction of the endometrium and inner myometrium. This animal model can be used to study the long-term consequences of EA and the association with EC.