Next, particles of polyvinyl alcohol (500 to 700 micron size) are injected slowly with fluoroscopic guidance. These particles wedge in the fibroid vessels and block them. Embolization is continued until there is near stasis (stopping) of flow in the uterine vessel. Once one side is completed, the other side is embolized. After the entire study, another arteriogram is performed. After embolization, all the fibroid vessels are gone with only very sluggish flow present in the uterine arteries, (black arrows in the figure above, right -- Post-embolization angiogram). Normal myometrial branches are spared (white arrows). The procedure takes approximately 1-2 hours.

Side Effects

Most patients will experience several weeks of symptoms after the procedure. This includes pelvic pain, nausea, and possibly fever. While some patients might be able to be discharged the day of the procedure, nearly all patients stay overnight and we strongly encourage them to do so. Patients are routinely given pain control via a PCA pump, which allows them to control their own pain medicine. Cramping pain, fatigue, and possibly fever are common side effects during the subsequent few days, but most symptoms resolve within several weeks. 

Procedural complications (<30 days) have been reported in less than 2% of patients. An ischemic (lack of blood flow) injury to the uterus of such severity that a hysterectomy is required is possible but occurs in only 1% of patients.  Severe infection can occasionally require a hysterectomy. Less severe infections have been reported and treated with intravenous antibiotics. Injuries to other pelvic organs has not occurred and the chance of other significant complications is less than 1 %.

Another potential side effect is diminished ovarian function. A small percentage of patients have lost their menstrual periods after this procedure. Nearly all have been at the age at which menopause typically occurs. The cause of this change is not known at this time. Studies are under way to determine if is there is a change in ovarian function in the majority of patients or whether any effects are limited to those who already peri-menopausal.

Expected Results

After the embolization, the fibroids infarct and degenerate over a period of weeks and months. Average fibroid volume reduction is approximately 50% in three months and 78% at one year. Uterine volume decreases by approximately 34% in three months. Two cases are shown in the accompanying figures.
The first case shows MRI's before and three months after embolization in a patient with multiple fibroids. The patient presented with severe menorrhagia, back pain and painful periods. In the pre-procedure MRI, the arrows indicate numerous fibroids (Case 1: Pre-embolization). Three months after embolization, the fibroids are infarcted and by measurement, the uterine volume decreased by 66% and the two dominant fibroids decreased by 86 and 91% (Case 1: Post-embolization). Her symptoms resolved.

The second case shows a large single submucosal fibroid in a patient with severe menorrhagia (Case 2: Pre-embolization). At three months after embolization, her symptoms had resolved and the fibroid had decreased 61% in volume (Case 2: 3 months after embolization). At one year, it had decreased 88% in volume (Case 2: 1 year after embolization). Her menstrual periods have remained normal in the 21 months since treatment.

 

The initial studies that have been published to date suggest that symptoms will be significantly improved or will resolve in 80-90% of patients. The patients in these series rated the procedure very tolerable. The long-term outcome is not known, in that recanalization of the arteries could occur or collateral vessels could be recruited which might allow regrowth of the fibroids. As of yet this has not been reported in the published series but only short-term follow-up is available at this time. Post-procedure fertility and the ability to carry a pregnancy to term is not known. Some of the patients in published series have successfully carried pregnancies but most patients have not sought to become pregnant and therefore the percentage that will be able to become pregnant is not known. Acknowledgement:  We wish to thank Dr. James B. Spies for permission to reproduce material from the Georgetown University web site.

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