A bipolar radiofrequency catheter fails to occlude a feline uterine horn: A model for fallopian tube occlusion.

We developed a retrograde transvaginal-transcervical-transuterine sterilization technique capable of causing occlusive fibrosis and stricture in the human fallopian tube. The procedure is required to induce a lesion at the intramural-isthmic portion of the tube at sufficient depth to damage epithelium underlying the submucosa and inner muscular layer, without acute damage to the outer muscular layer and serosal surface. Nineteen nulliparous purpose-bred cats were induced and maintained in an anestrus state with testosterone cypionate 5 mg/kg intramuscularly and a 6-18-hour light-dark cycle. After laparotomy, all animals had focal radiofrequency lesioning of uterine horns. Ten of 30 treated uterine horns appeared grossly occluded at the time of sacrifice; however, histologic assessment demonstrated only 6 complete occlusions, and 4 horns showed lack of complete lumen occlusion with or without evidence of recanalization. Although no complications were encountered, bipolar radiofrequency failed to provide a consistent obstructive lesion in a tubular structure similar in size and morphology to the human fallopian tube.