Transcervical microwave myolysis for uterine myomas assisted by transvaginal ultrasonic guidance

AIM: The effects of transcervical microwave myolysis at 2.45 GHz after microwave endometrial ablation for menorrhagia were examined in patients with myomas. METHODS: A transcervical microwave irradiation system assisted by transvaginal ultrasonic guidance was developed. Ten patients waiting for microwave endometrial ablation for menorrhagia caused by myomas entered the study after complete informed consent was obtained. Their outcomes were examined at least 6 months after transcervical microwave myolysis using the system. After completion of microwave endometrial ablation, interstitial microwave irradiation was performed using a guiding needle set in a puncture adaptor attached to a transvaginal ultrasonic probe and a microwave applicator of 1.6 mm in diameter. Shrinkage of the myoma was measured at 3 months and > or =6 months after the operation. RESULTS: In nine patients with typical myomas, the major part consisting of a submucous or an intramural node 4.0-7.5 cm in size was necrotized. The typical myomas had shrunk by 41-68% at 3 months and 37-69% at > or =6 months after the operation. In one patient with a 6.8-cm cellular leiomyoma, necrosis was limited to the neighborhood of the applicator tip. Shrinkage was 17% at both 3 and 6 months. This patient required a second microwave endometrial ablation at 6 months to treat recurrent menorrhagia. None of the patients underwent hysterectomy after the treatment. No remarkable complications were encountered. CONCLUSIONS: Typical myomas shrink after microwave myolysis following microwave endometrial ablation. Transcervical microwave myolysis seems to be applicable as a low-invasive treatment for a typical myoma.