Early Ovarian Failure The risk of premature ovarian failure following UAE needs further study. Transient amenorrhea was reported in as many as 15% of women. Ovarian arterial perfusion as measured by Doppler sonography immediately following UAE shows that 35% of women had decreased ovarian perfusion and 54% had complete loss of perfusion (169). However, basal follicle-stimulating hormone (FSH) and antim¨ullerian hormone levels indicated decreased ovarian reserve in all women in one study (170).
Although normal FSH, estradiol, ovarian volume and antral follicle counts were documented in most women following UAE, these tests cannot predict earlier onset of menopause (171).
Figure 15.8 (Continued) B. Contrast dye shows the vessels supplying the fibroid prior to UAE.
C. Following UAE, embolic material blocks blood ﬂow to the fibroid.
Younger women, whose ovaries contain a large number of follicles, are likely to maintain a normal FSH despite destruction of a significant number of follicles, but it is not clear if future fertility will be impaired. Loss of follicles might cause menopause at an age earlier than would otherwise be expected. Long-term follow-up of women having UAE will be necessary to answer this important question.
Alternative methods of uterine artery occlusion were developed, both more and less invasive than UAE, including laparoscopic uterine artery occlusion and nonincisional transvaginal uterine artery occlusion. Fifty-eight patients were randomized to UAE or laparoscopic uterine artery occlusion (177). After a median follow-up time of 48 months clinical failures and symptom recurrence occurred in 14 women after laparoscopy (48%) and in five women after UAE (17%). Laparoscopic occlusion requires general anesthesia, is invasive, and requires a skilled laparoscopic surgeon. Transvaginal occlusion is performed by placing a specially designed clamp in the vaginal fornices and, guided by Doppler ultrasound auditory signals, is positioned to occlude the uterine arteries (178). The clamp is left in place for 6 hours and then removed. Results of this approach are not yet known.
Ultrasound energy can be focused to create sufficient heat at a focal point so that protein is denatured and cell death occurs. Concurrent MRI allows precise targeting of tissue and monitoring of therapy by assessing the temperature of treated tissue (179). The advantages of this procedure are a very low morbidity and a very rapid recovery, with return to normal activity in one day. The procedure is not recommended for women wishing future fertility (179). Initial studies had treatment limited by the U.S. Food and Drug Administration to approximately 10% of fibroid volume, and while a 15% reduction in fibroid size was reported 6 months following treatment, only a 4% reduction was noted at 24 months (180). More recent studies with larger treatment areas reported better results; 6 months after treatment, the average volume reduction was 31% (+/−28%) (181).
An evaluation of clinical outcomes 6 months after treatment found that 71% of women had significant symptom reduction, but at 12 months about 50% still had significant symptom reduction (180). Twenty-three of 82 (28%) evaluable patients had undergone subsequent hysterectomy, myomectomy, or UAE. Women actively sought out magnetic resonance–guided focused ultrasound (MRgFUS), and no control group (sham MRgFUS) was included, so a placebo effect cannot be ruled out. One woman had a sciatic nerve injury caused by ultrasound energy and 5% had superficial skin burns. It remains to be seen whether increased treatment volumes will be associated with increased risks. As the technology continues to develop, further studies will be needed to evaluate the risks and efficacy of MRgFUS in the treatment of uterine fibroids.