Uerine artery embolization (UAE) has received considerable attention in recent years as increasing numbers of women seek less invasive methods for treating uterine leiomyomas (fibroids). Consequently, many interventional radiologists and their affiliated institutions are questioning whether they should add UAE programs to their clinical services. UAE is currently offered at only about 200 centers in the United States, although increased demand for the procedure is causing many hospitals to add the service. To perform UAE, an interventional radiologist injects embolic material into the branches of the uterine artery, blocking blood flow to the fibroid, which causes it to shrink.
|Figures a-d left to right: a). A nonselective arteriogram of the pelvis demonstrating the torturous and dilated appearance of uterine arteries supplying a hypervascular uterine fibroid. b). Image taken after a catheter has been placed selectively in the left uterine artery. c). Image taken after a catheter has been placed selectively in the right uterine artery. d). Once the arteries are embolized, they are no longer visualized angiographically. Images courtesy of Gary Siskin, MD, Albany Medical College, Albany, NY.|
Since uterine fibroids are the most common gynecologic condition requiring medical treatment and occur in 20% to 25% of women of child-bearing age, it makes sense that many institutions offering women’s health services are now including UAE. When clinically diagnosed, uterine fibroids are often asymptomatic; however, for many women, they can grow at very rapid rates and result in heavy prolonged menstrual bleeding, intermenstrual bleeding, increased urinary frequency, stress incontinence, and pelvic pain. Until recently, women suffering from these symptoms would receive medical therapy or surgery (hysterectomy or myomectomy). These procedures, however, are invasive with higher complication rates and longer recovery periods. Although hysterectomy remains the major invasive treatment for uterine fibroids, UAE has quickly gained approval by physicians and patients seeking a nonsurgical alternative.
James B. Spies, MD, director of Georgetown University’s Uterine Embolization Program, chief of service of radiology, and professor of radiology, understands the growing popularity of UAE and is one of its strongest advocates. His center has treated approximately 1,100 patients since it opened in 1997. “This is a great procedure for many women, especially those in their mid 40s who have not yet gone through menopause,” he says. “It clearly improves the lives of many women,” says Spies.
He notes that hospitals recognized for their women’s care services, particularly those that already perform hysterectomies for uterine fibroids, may want to consider offering UAE. Since African-American women are about three times more likely to develop fibroids, he adds that institutions located in areas with this demographic group typically find UAE to be a beneficial service.
A SignificanT Shift
Despite the growing popularity of UAE, Spies and other interventional radiologists stress that hospitals should carefully consider the viability of such a program. The major considerations are the investment in space and personnel time. Individual radiologists or practices interested in pursuing UAE need an angiography or fluoroscopy suite. Most facilities that employ interventional radiologists have these facilities. “Most important, you need to have an interventional radiologist who is committed to this service and is willing to devote the necessary time to make the program succeed,” says Spies.
Gary Siskin, MD, division director, Institute for Vascular Health and Disease, Albany Medical College, Albany, NY, agrees that one of the biggest issues for physicians taking on this service is the time commitment needed to treat patients successfully. “This procedure has forced physicians to practice differently,” says Siskin. “The most successful centers are those in which the interventionalist sees the patient in their office before the treatment, takes responsibility for getting preapprovals and preauthorizations and admits the patient to their service overnight for pain management,” he says. Patients generally need about an hour of consultation time prior to the procedure, letters need to be written to insurers and patients’ physicians, and patient questions often need to be addressed in phone calls and follow-up appointments. All of this requires considerable time, and some interventional radiologists who have not offered this procedure before are surprised by the nature of this work. Due to the extent of this workload, many practices use a physician’s assistant or nurse practitioner to help manage the service.
Most UAE services do not require large support staffs. A receptionist/scheduler is needed, but an individual who already works in the radiology department can take on this role. Busier practices may need two employees to share this function. A nurse is generally needed to evaluate and educate patients as well as coordinate overall clinical care. This individual does not have to be a full-time employee and can also work with other patients in the angiography department or some similar area. According to Spies, the key is to have staff knowledgeable enough to answer questions. “Many patient questions come up, and although the interventionalists can answer them directly, if they’re in the middle of procedures, someone else needs to be able to answer them,” he says. Most UAE services also initially use a pain specialist or anesthesiologist to help establish protocols that coincide with hospital policies.
Acquiring the necessary inventory to start a UAE service is not difficult since the products are usually routinely stocked in most interventional departments. “Many interventionalists could walk into any hospital and do these procedures tomorrow with supplies right off the shelf,” says Spies. Catheters, microcatheters, guide wires, and specific embolic agents comprise the inventory. Specifically, the facility should have a digital subtraction angiography suite, preferably with a “road-mapping” technique to expedite the procedure.
Once staffing and space are addressed, it is tempting for many interventional radiologists to immediately start marketing the service. “This is one of the biggest mistakes that can be made,” stresses Spies. “On many occasions, these programs are started before protocols have been established and without any planning related to scheduling and discharge procedures.” Spies advises individuals who are just starting a UAE service to network with several gynecologists on staff to inform them about how the service can benefit their patients. Once several patients have been treated and a track record has been established, it is easier to implement marketing strategies. If the service has other competitors in the area, it becomes especially critical to market to referring physicians, specifically gynecologists, to demonstrate the strengths of the program. Many new UAE services develop a brochure describing the procedure that can be distributed to referring physicians.
Because some gynecologists still view UAE as a threat to their clinical practices, it can be challenging to establish an effective referral system. A large percentage of patients who inquire about UAE do not receive referrals from their gynecologists, but instead learn about the procedure from the Internet or television. Most interventional radiologists agree that the key to succeeding in this specialty is to promote collaboration with gynecologists. Although in most cases the interventional radiologist is fully capable of handling the procedure from start to finish, there are some potential complications or situations that may require gynecologic surgery. Therefore, it makes sense to build strong relationships with gynecologists who might need to provide follow-up care. An effective strategy is for interventional radiologists to give presentations on UAE during in-house meetings of the hospitals’ gynecology staff. As gynecologists continue to learn that UAE is an excellent option for many patients with fibroids, the relationship between the two specialties should improve.
Marketing The Service
After a UAE service is up and running and has been endorsed by a few referring gynecologists, it is an appropriate time to start formally marketing the service. In general, the marketing costs associated with launching a UAE service are relatively low. Siskin points out that one of the most effective means of marketing is to work with the hospital’s public relations department to bring visibility to the service. Most local television stations and newspapers are anxious to include news items on leading-edge medical developments, particularly if they feature noninvasive alternatives to surgery. “Showcasing patient success stories through local news media can be every bit as effective as, if not more effective than, advertising a service on a billboard,” says Siskin.
Since start-up costs are relatively low, a facility does not have to perform many procedures before breaking even. “I would estimate that once you’ve treated 10 or 20 patients, you would have paid for whatever minor costs were spent to launch the service,” says Spies. A UAE procedure earns a hospital the same amount as a hysterectomy, so from a financial perspective it makes sense to add this procedure to an institution already offering hysterectomy. “If you take in just 20 additional patients, it probably would pay the equivalent of one hospital FTE,” he says. In other words, the service would more than cover the additional costs related to staff, clinical space, and supplies. As Spies stresses, the key is having an interventional radiologist serving as a leader to build the service and then a hospital willing to supply the relatively minimal resources.
If UAE is profitable, why are many institutions still dragging their heels in launching the service? According to Spies, one of the biggest barriers is the current shortage of interventional radiologists in the United States. “There has been a demographic shift in radiology with many students more interested in the imaging area than the surgical subspecialty, so we’re experiencing a decrease in the number of trained interventional radiologists,” he says. In turn, many practicing interventional radiologists have difficulty finding time to add new programs in their institutions. To help attract more students into the field, the Society of Interventional Radiology (SIR) has been working with the American Board of Radiology to develop a more direct pathway to interventional radiology rather than through the traditional pathway of a complete diagnostic radiology residency. Such a pathway might attract students interested in interventional procedures but who are reluctant to complete diagnostic radiology training first.
Although a variety of materials can be used as embolic agents for uterine artery embolization (UAE), those most commonly used are polyvinyl alcohol (PVA) particles, gelfoam, and embospheres. Each of these agents is slowly injected through a catheter to the uterine artery in order to block the blood supply to fibroids.
Polyvinyl Alcohol Particles (PVA). Most UAEs in the United States are performed using PVA particles. Ground from blocks of foam and then separated into different size groups, PVA has been used as an embolic agent since the 1970s. The most common sizes used for UAE are 355 to 500 microns and 500 to 710 microns. PVA has been widely used because it is relatively inexpensive and is easy to deliver. Most interventional radiologists have extensive experience using PVA, and numerous published studies have indicated that it is safe without causing any known long-term side effects. At the same time, some interventional radiologists prefer not to use PVA because the particles swell after they mix with saline or contrast, which can cause them to clump within vessels after an injection. This may completely block the uterine artery. Today many experts believe that only the vessels leading to the fibroids need to be blocked instead of the entire artery.
Gelfoam. Gelfoam is a dissolvable sponge-like material that has been used for many years in surgery to help stop bleeding. It comes in small, flat rectangular blocks and can be applied to a minor area of bleeding during surgery and helps form a clot. Although it has been used as an embolic agent for other procedures for many years, it has been used less frequently for UAE. Gelfoam differs from PVA in that it is absorbed by the body within 7 to 21 days of embolization. As a temporary agent, gelfoam is believed to dissolve, causing the artery to reopen in several days to a few weeks. Although the reopening of the uterine artery has not been documented, some experts speculate that the gelatin sponge should be used by patients wishing to preserve fertility because of the perception that the artery will reopen. Studies are needed to determine the long-term rate of recanalization of the uterine arteries when gelfoam is used.
Embospheres. A new alternative to both PVA and gelfoam is embospheres, spherical particles made from a trisacryl polymer matrix embedded with porcine gelatin. The primary advantage of these calibrated microspheres is that they are more uniformly sized, which minimizes catheter clogging and provides a more predictable level of embolization. Research has also found that embospheres are more likely than other types of particles to block the fibroid vessels without closing the entire uterine artery. During a scientific session at last year’s Society of Interventional Radiology meeting,1 researchers compared the rates of blood flow reduction with PVA and embospheres in a swine model. The study concluded that embospheres reduced renal blood flow more quickly than did PVA. Embospheres received FDA approval in May 2000 for general use for embolization, although they have been used in Europe for many years for both UAE and other embolizations. The initial clinical results of embospheres are very promising. Currently, there is no definitive evidence that one embolic agent is superior to others. Interventional radiologists typically select the material based on the individual patient’s circumstances and their preference. Ongoing studies and clinical trials will help physicians determine which products are best suited for specific patients.
Cost-Effectiveness of UAE
As increasing numbers of women with symptomatic leiomyomas are having uterine artery embolization (UAE), greater attention is being focused on the financial aspects of the procedure. Researchers from Massachusetts General Hospital conducted the first study of its kind to determine if UAE is a cost-effective alternative to hysterectomy. The results of the study were published in the January 2004 issue of Radiology.
“Although the actual UAE procedure is more expensive than hysterectomy, from a societal perspective the savings from reduced patient recovery time more than make up the difference in the costs of the procedures,” says Molly T. Beinfeld, MPH, lead author of the study. The average cost to society, related to direct medical expenses, missed work during recovery, and other factors, averaged $7,847 for hysterectomy compared to $6,916 for UAE. These costs are societal in that patient and follow-up costs, along with hospital and physician fees, were factored into the estimates. The costs were computed from the 1999 Medicare Provider Analysis and review database as well as global health data.Â
The researchers developed a Monte Carlo Markov decision model to compare the costs and effectiveness of UAE and hysterectomy. They studied a group of women each over the age of 40 with a diagnosis of uterine fibroids and no desire for future pregnancy up until menopause. Sensitivity analyses of key estimates were performed, and the results were expressed in costs per quality-adjusted life year (QALY).
Despite the lower societal costs, analysis by Beinfeld and her colleagues found that UAE had higher procedural costs, $5,467, compared to $4,795 for hysterectomy, regardless of the shorter hospital stay: 1 day compared with 2.6 on average for hysterectomy. The one-week recovery time associated with UAE, however, ends up playing a major role in keeping the cost down. As the authors point out, complications occur with approximately 10% to 15% of hysterectomies and a recovery time of about 6 weeks is expected. UAE, on the other hand, has a low complication rate and reduced recovery times.
According to Beinfeld, since both UAE and hysterectomy are safe procedures and are associated with very low mortality risk, any difference in effectiveness of the two procedures will depend on the impact they have on the patient’s quality of life.Â “Unfortunately, there is still little data in this area,” she reports.
Although the procedure is noteworthy because of its cost-effectiveness, the authors point out that the viability of UAE also depends on long-term factors, such as fibroid recurrence, quality of life, need for repeat procedures, and direct costs to patients, employers, and the health care system. Still, the study is important because it demonstrates to insurers and health care providers that this minimally invasive procedure is a cost-effective alternative to hysterectomy.
Carol Daus is a contributing writer for Decisions in Axis Imaging News.
- Andrews RT, Binkert CA. Rates of blood flow reduction with polyvinyl alcohol and tris-acryl gelatin microspheres: quantification in swine. J Vasc Interv Radiol. 2003;14:S38.