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Will it work for me?

The answer to this question depends entirely on your individual situation. If uterine fibroid embolization (UFE) is to be effective, several things must be true:

First of all, of course, your symptoms have to be caused by a fibroid. This may seem like an obvious point, but not every woman with bleeding or pain has fibroids, and not every fibroid causes symptoms. Second, your symptoms should be significant enough that they are impacting your quality of life. Although UFE is minimally invasive, it is still a medical procedure with potential complications. It should not be performed unless there is a real problem to fix. Third, there should be no other medical condition that makes hysterectomy a more appropriate option. For instance, if you also have a known or suspected malignancy in your cervix, ovaries, or uterus, then UFE is not appropriate as a stand-alone treatment (although it might be performed before surgery to reduce bleeding).

To be sure that each of these issues is addressed, every woman considering UFE must be completely evaluated by a doctor with experience and training in women's health. For a list of gynecologists in your area, click here.

Does the size, number, or location of my fibroids matter?

In a word, "no." The embolization procedure treats all of a woman's fibroids at once, no matter how large or where they are located. This is good news, because women with large fibroids, multiple fibroids, or fibroids located in the lower rear of the uterus are usually not candidates for myomectomy. Before UFE, these women would probably have required hysterectomy.

Now the bad news:
Although UFE treats large fibroids as easily and effectively as small ones, the final size is directly comparable to the beginning size. That means that a huge fibroid will probably still be very big after embolization. Most fibroids shrink by 50-65%, or about half. That amount is enough to relieve symptoms in most women, but not in all.

Some fibroids get a portion of their blood supply from vessels other than the uterine artery. This is called "parasitized flow," and is impossible to detect. The source can be ovarian arteries, intestinal arteries, and arteries from other structures in the pelvis. We are often unable to find these vessels, and may not be able to treat them safely even if they can be found. If a lot of "parasitized flow" is present (and there is no way to predict this), then the fibroid might not shrink after UFE.

What happens to the fibroid(s)?

The embolized fibroid immediately loses its supply of oxygen, nutrients, and hormonal stimulation. Over the subsequent weeks and months, individual muscle cells in the fibroid die off and are replaced by scar tissue. This process, technically called "hyaline sclerosis." occurs slowly, and is exactly the same thing that occurs when a fibroid spontaneously loses its blood supply. Because the individual cells die off one at a time, there is no large mass of dead tissue in the body. The trade-off is that fibroid symptoms do not immediately disappear, as they would with hysterectomy or myomectomy.

Eventually, the fibroid is replaced by a lump of scar tissue. This scar is about half as big as the original fibroid, or perhaps slightly smaller. Because scar tissue does not respond to hormonal stimulation as fibroids do, the normal menstrual cycle no longer causes growth. Nor do birth control pills. On the other hand, the size will probably not get any smaller after menopause.

What happens to the uterus?

The uterus tolerates the UFE procedure very well. Among Dr. Ravina's first patients, several underwent hysterectomy (remember, they were embolized prior to scheduled surgery). Laboratory analysis of their uteri showed no UFE-related injury to the normal uterine muscle or the lining of the uterine cavity. Only the fibroids were affected. The same has been observed in animal studies and in the clinical follow-up of human patients who did not have hysterectomy after UFE. In short, injury to the normal uterus is extremely rare.

There are two main theories to explain these findings. First, the arterial branches that go to normal uterine tissues are tiny, while the arteries that go to the fibroid are very large. Injected polyvinyl alcohol (PVA) particles are too big to enter vessels leading to the normal uterus, so they roll right past these vessels and go where the blood flow and vessel diameter are greatest. The fibroids, by being so greedy for blood flow, preferentially absorb the blood-borne PVA. Second, the uterus is able to "recruit" blood supply from adjacent organs, primarily the cervix, vagina, and pelvic floor.

What happens to the particles?

The most common material used for UFE is polyvinyl alcohol (PVA). All PVA is approved for human use by the FDA, and some specifically for UFE. PVA is a plastic powder, and a permanent embolic agent. The particles do not get absorbed, do not dissolve, and cannot migrate to other parts of the body once they are in place. PVA causes little or no reaction by the body, and has never been associated with the kind of delayed complications that have been seen with breast implants.

Acryilic spheres are an unique embolic agent FDA approved for UFE. These spheres are very uniform in size, and slightly compressible. They are permanent embolic agents, with similar properties as PVA.

Gelfoam, another commonly used embolic agent, has also been in common use for decades. Like PVA, gelfoam cannot migrate to other parts of the body once it is in place. It is made of protein and is absorbed by the body over a period of several weeks. Thus, gelfoam is a temporary embolic agent. The temporary nature of occlusion with gelfoam may be an advantage, but we don't yet know whether gelfoam is as effective as PVA.

Do the fibroids come back?

This will be another slightly complicated answer. Remember that UFE shrinks, but does not remove, the fibroids. Since they don't actually "go away", the question actually has three parts: a) can the shrunken fibroids regrow, b) can new fibroids develop after UFE, and c) if fibroids regrow or new ones form, can they cause enough symptoms to require treatment? In several large randomized prospective studies comparing UFE to surgical treatments, up to 10% of the UFE patients needed a second treatment of some sort. Some of these treatments were related to incomplete shrinkage of the fibroids. Patients who have many years of menstrual cycles after UFE can develop new fibroids, some of which can cause symptoms. This is not too surprising, as all of a woman's reproductive organs are intact after UFE compared to hysterectomy. Fortunately, these problems are rare, but can often be managed with repeat UFE. For the sake of comparison, myomectomy patients (surgical removal of just the fibroids, leaving the uterus and ovaries) have an expected recurrence rate of up to 25%.

These statements must be viewed with caution: the first group of women treated with UFE consisted of just a few individuals, and the largest group of patients has only been followed for about three years. The truth is that we really don't know yet whether some women will eventually grow new fibroids. However, it is very encouraging that no one has seen this happen yet.

Will I still have menstrual periods?

95% of women will continue to have menstrual periods after UFE. Roughly 5% of women in one published study did enter menopause after UFE, but the reason for this is not clear. It may be coincidental, but there is also the possibility that some of the injected particles caused a reduction of blood flow to the ovaries or that the X-rays used during the procedure caused an ovarian injury.

Will I still be able to have children?

As noted above, a small number of women enter menopause after UFE. The rest maintain their baseline fertility. We know this because several women have had successful pregnancies, carried to term, after UFE. We also know from years of experience that, when the uterine artery is embolized or surgically tied off for pelvic trauma, fertility remains normal.

What we do not know is whether UFE will shrink fibroids enough to improve fertility in women who have had problems with miscarriage. In addition, the ovaries and eggs are exposed to X-rays during UFE, which may slightly increase the risk of genetic damage and may increase the risk of birth defects.

Is it experimental?

UFE is an approved procedure for treatment of fibriods in properly selected patients. There are several FDA approved embolic agents specifically for this procedure. However, there is still much to be learned about this procedure and many institutions are conducting research in this area. You may be asked to participate in one of these studies depending upon where you undergo the procedure.

It is important for patients to understand that while the results of UFE for fibroids have been excellent, we only have a few years' worth of patient follow-up. It is possible that the long-term outcomes will be no better than other treatment options.

Does it hurt?

The amount of pain that women experience during and after UFE is extremely variable. We do not yet have a good mechanism for predicting the degree of pain that an individual patient will feel, but it does not seem to be related to fibroid size or number. Most women experience at least moderate cramping. Some women have more pain. Fortunately, the pain can be controlled with medications, and it usually only lasts for 24-72 hours. Most women prefer to remain in the hospital overnight, but are home the next day by noon.

During the embolization procedure, which takes about an hour, most IR's use intravenous medications for patient comfort. The most common choices are Fentanyl, Versed, Toradol, and morphine, in doses tailored to the individual patient. Some IR's use epidural anesthesia, which is delivered through a catheter in the back. (many women are familiar with this approach, as it is commonly used during childbirth.) General anesthesia is not used, for two reasons: first, the pain is not severe enough to justify the risks of general anesthesia; and second, pain usually does not begin until the end of the procedure or afterward, when the anesthesia would be gone.

Is it dangerous?

When performed by an experienced IR, embolization is a very safe procedure. Although there can be complications, they are uncommon.

The most serious potential complication is infection. If an infection developed after UFE, it could require hysterectomy. Of course, infections can also develop after myomectomy, hysteroscopy, or hysterectomy. Patients should be treated with antibiotics during UFE or surgery, and pre-existing pelvic infections need to be resolved prior to the procedure.

Although unlikely, it is possible for blood flow to other organs to be blocked during UFE. This complication can result in injuries to the urinary bladder, the intestine, the ovary, or other adjacent structures. Fortunately, this complication can be avoided with careful technique and x-ray guidance during embolization. As with infections, injury to adjacent organs is a risk of both UFE and the common surgical alternatives. The use of x-ray guidance is mandatory for UFE. The specific amount of radiation received by the uterus and ovaries in any given UFE procedure is directly related to the time required and the techniques used by the IR. While no particular dose of radiation can be shown to cause a specific risk of injury, less is better than more. Surgical and medical treatment alternatives do not use x-rays.

Is it better than the other options?

The answer to this question depends entirely on your situation. We feel that the most appropriate patient for UFE is a woman who has completed her family, who does not want or cannot tolerate surgery, and has symptoms that are clearly caused by a fibroid of moderate size (about 7 cm) and are not responsive to medications.

Patients who desire future pregnancy, and who are candidates for myomectomy or hormonal therapy should still consider these to be their main treatment options. We simply do not yet know whether UFE has the same safety and efficacy for patients who are still planning for children. In addition, the ovaries and eggs are exposed to x-rays during UFE, which may slightly increase the risk of birth defects. Patients with extremely large fibroids should probably consider hysterectomy to be a better option. As indicated above, UFE can decrease fibroid size, but only by 50-65%. For example, a basketball-sized fibroid would probably not be smaller than a softball after UFE.

At OHSU, the Center for Women's Health operates a clinic devoted to helping women manage fibroids and other gynecologic problems without resorting to hysterectomy. The clinic is an excellent resource for women who have questions about their management choices. For more information, click here.

Will my insurance cover it?

Many insurance companies cover UFE on a routine basis. Others do not. The only way to know in an individual case is to contact the insurance company's representatives. However, before checking with your own company, you should be sure that you are an appropriate patient for the procedure. Discuss your case with your primary health care provider and your local IR. If they agree that the procedure is right for you, then you can present this fact to your insurance company. If payment is denied, your doctors can help you with an appeal.

What do I do next?

If you have additional questions about UFE, contact an Interventional Radiologist (IR) in your area. For questions about fibroids in general, or about some of the other treatment options, contact a gynecologist.

The process of evaluating a patient for UFE begins with your primary health care provider. He or she will verify whether you have a fibroid, and whether it is responsible for your symptoms. He or she may order special imaging studies or blood tests to be sure that there are no other problems that also need to be addressed.

The next step is to discuss your case with an IR. The IR will need to review your related medical records and ultrasound (or other) imaging studies. You will need to give written consent to have these records copied and sent to him or her.

If you, your IR, and your primary doctor agree that UFE is the right choice for you, the next step is to contact your insurance company for authorization.