With excessive menstrual bleeding prompting about 2.7 million visits to United States physicians each year, it should come
as no surprise that American women are looking for treatment options.1 Among the nonsurgical options we discussed in Part 1 of this series (November 2005) were nonsteroidal anti-inflammatory
agents, oral contraceptives and progestins, danazol, the antifibrinolytic agent tranexamic acid, the levonorgestrel-releasing
intrauterine system, and gonadotropin-releasing hormone (GnRH) agonists.
But when medical therapy fails or is not acceptable to the patient, many surgical options exist. Dilation and curretage is
commonly performed, but usually offers only temporary relief. It is best used as an acute treatment for severe bleeding or
as a diagnostic procedure evaluating possible neoplasm. Let's review some of the other approaches.
Endometrial ablation
In general, there are two categories of ablative methods, standard and global. Standard endometrial ablation is performed
through an operative hysteroscope under direct visualization. This can be done using laser, rollerball desiccation, or endomyoresection
with a wire loop. Global ablation procedures differ in that an operative hysteroscope is not required and the procedure is
largely automated. Many of these procedures are performed blindly. Specific pros and cons of endometrial ablation vary with
the particular system used.
Table 1. Surgical options for managing menorrhagia
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[Endometrial ablation is typically reserved for premenopausal patients with dysfunctional uterine bleeding (DUB) who have
no interest in getting pregnant and who have failed medical management, do not want to take medication, or for whom medical
therapy is contraindicated.] Women with structural lesions, including large unresected fibroids and polyps as a cause of their
bleeding, or suspected neoplasms are generally not good candidates for ablation.
Endometrial ablation has several advantages. It is typically an outpatient procedure, has low morbidity, and is less invasive
than hysterectomy. Disadvantages include the possible need for repeat ablation or hysterectomy. One study has found that up
to 40% of patients undergoing electrocautery, laser, or radio-frequency ablation required a second ablation or hysterectomy
within 4 years.2 A meta-analysis has concluded that subsequent operative rates or need for a second procedure are not significantly different
between standard and second-generation techniques including balloon, VESTA, microwave, and a hydrothermoablator.3
[Unfortunately, long-term outcome studies on some of the newest ablative procedures are not yet available. Major complications
of these procedures are uncommon but can include uterine perforation, endometritis, hematometra, thermal injuries to surrounding
structures, and bowel injury.4 ] When compared with the levonorgestrel IUS, endometrial ablation was found to be more effective in controlling menstrual
blood loss at 1 year, but was equivalent at 2 and 3 years. Satisfaction rates and quality of life were equivalent at 1, 2,
and 3 years with both treatments.5
The use of GnRH agonists to thin the endometrial lining prior to hysteroscopic resection or ablation has been associated with
shorter operative time, easier surgery, and a higher rate of postoperative amenorrhea at 12 months, and reduced postop dysmenorrhea,
when compared to no treatment. GnRH agonists appear to produce slightly more consistent results than danazol.6 Progestins have also been used preoperatively to decrease endometrial thickness, but are less well studied.
Standard ablative procedures
Advantages of standard ablative procedures like laser, rollerball desiccation, or endomyoresection include direct visualization,
which permits immediate detection of structural anomalies, uterine perforation, and bleeding. These procedures can also be
performed in about 10 minutes by an experienced operator.
Disadvantages of standard ablative procedures include the need to perform the procedure in an operating room under general
anesthesia because of the discomfort of electroablation and cervical dilatation, which is needed to accommodate a large operative
hysteroscope. In addition, these procedures require considerable operator skill and strict monitoring of the intake and output
of distension fluid to avoid complications related to volume overload and hyponatremia.
Global ablative procedures
[Hot water balloon ablation represents one of the earliest global methods. The principal advantage is its ease of use; minimal operator skill is required.]
A silicon balloon (Thermachoice) is passed through the cervix via a 4- to 5-mm probe into the uterus, where it is expanded
with saline to 150 to 180 mm Hg, and heated to about 87C for 8 minutes.7 However, to uniformly ablate the endometrial cavity, a smooth cavity is preferable.
Hydrothermal ablation is achieved by directly circulating hot water through the uterine cavity. This procedure is performed under direct visualization
through an 8-mm hysteroscope. After saline is introduced into the cavity by gravity, it is heated to 90C for about 17 minutes.
Because the water expands to fill the entire cavity, all surfaces are treated, which means it's effective for even irregularly
shaped cavities. Disadvantages include the risk of burning the cervix, vagina, or peritoneal cavity via leakage of hot water
through the fallopian tubes. A safety mechanism built into the system automatically turns off the instrument if more than
10 mL of fluid is lost. Pain can be significant from both the heat and cervical dilatation needed to pass the 8-mm instrument.
These considerations mandate the use of general anesthesia.
Bipolar desiccation of the endometrial lining has also been performed using a three-dimensional expandable mesh (NovaSure). The procedure is
rapid and easy to learn. After introduction into the endometrial cavity, the mesh is expanded with sufficient pressure to
achieve contact with the entire surface of the cavity. A vacuum is then created in the cavity to ensure the lining is completely
applied to the probe. The system automatically detects complete desiccation when 50 ohms of resistance is achieved, usually
within approximately 1 to 2 minutes. The average depth of ablation is 4 to 5 mm. A regular endometrial contour is required
for this method as well.
Microwave ablation (Microsoulis) is a relatively cost-effective alternative that uses a reusable probe. This microwave system consists of a
9.2 GHz, 30-W probe that's inserted into the uterine cavity. The probe is directed toward each cornu and then the lower uterine
segment in order to heat the cavity to about 95C. The depth of thermal ablation is approximately 6 mm. The procedure takes
less than 5 minutes. Its major disadvantage is the necessity of an 8-mm instrument and usual requirement of general anesthesia.
ELITT (endometrial laser intra-uterine thermal therapy) is a global laser technique consisting of an IUD-like device that contains a 21-W diode laser light system (GyneLase) that
diffuses well in irregularly shaped cavities to treat the entire endometrial surface. The device consists of three fibers:
two lateral fibers diffuse light up to 3 cm away and the middle fiber diffuses light to 4 cm. It is cost-effective and is
quite suitable for the office setting, given it requires only a 6-mm diameter instrument. The procedure takes 7 minutes. The
fact that it is performed blindly, of course, is a drawback.
[Cryoablation differs from typical global ablation procedures: It is not automated and the progress of the procedure is monitored using
real time ultrasound.] (Her Option, American Medical Systems) The probe is inserted into the uterine cavity and cooled to
–90C, producing an elliptical ice ball. Only tissue in the center of the ice ball is destroyed. The outer 4 to 6 mm of the
ice ball is frozen but not destroyed. The technique used to perform cryoablation is similar to the microwave system, in that
the probe is directed towards each cornu individually. This permanently destroys the basalis layer of the endometrium. The
clinician uses ultrasound to follow the progression of the ice front. The cooling cycle is usually terminated when the ice
front reaches between 3 to 5 mm from the surface of the uterine serosa or after 7 minutes of freezing. The probe is then warmed
(which releases it from the frozen tissue) and repositioned to the opposite cornu. A third freeze in the lower uterine segment
may be appropriate when uterine sounding exceeds 10 cm.
By using a freezing technique to ablate the endometrium, the nociceptive response is decreased resulting in less pain and
cramping than heat-based therapies. Also, since the operator can directly observe the progression of the ice front using ultrasound,
the risk of complications, such as unrecognized uterine perforations or thermal bowel injury, is minimized. Particular attention
must be paid to the lower uterine segment with ultrasound in patients with previous C-sections, as this area may be much thinner
than the fundus. Because this procedure is well-tolerated, cryoablation can be performed in an office setting. Although it
is usually performed on normal endometrial cavities, ablations of submucosal fibroids smaller than 3 cm have been reported.8
Myomectomy
[In premenopausal patients with fibroid-induced abnormal uterine bleeding (AUB) who want to remain fertile, a myomectomy can
be performed either by the abdominal, laparoscopic, or hysteroscopic approach. In one study, menorrhagia resolved in 84% of
women who underwent myomectomy.9] Keep in mind, however, that a suspected malignancy is a contraindication for such conservative surgery.
Major drawbacks to this operation include an often high operative blood loss, the risk of subsequent adhesions, formation
of a uterine scar that increases the risk of uterine rupture during subsequent pregnancies, and placental implantation abnormalities.
Fibroids may also recur, which may necessitate further surgery. One study found 84% of women (79/94) experienced complete
resolution of menorrhagia after myomectomy.9
Uterine artery embolization
Uterine artery embolization is an increasingly popular alternative to surgical therapy. [Studies suggest that over 80% of
patients experienced significant improvement of menorrhagia.10,11 The rate of amenorrhea following embolization is highly age dependent, however. In one study, rates ranged from 3% (1%–7%)
in women under age 40 to 41% (26%–58%) in women aged 50 or older.11]
During the procedure, the physician accesses the femoral artery and an angiogram is performed to identify the uterine artery
and blood supply to the fibroids. Under fluoroscopic guidance, a catheter is advanced to the distal portion of the uterine
artery. The uterine artery is embolized using acrylic copolymer beads or polyvinyl alcohol (PVA) foam particles until flow
to the fibroid is absent, and slight antegrade uterine artery flow is still present.
Serious complications appear more likely when there is a single large myoma. Complications can include inadvertent embolization
of ovarian vessels leading to ovarian failure, significant hypoxic pain requiring hospitalization and opioid administration,
risk of embolization of the iliac or femoral arteries, risk of bleeding intra-abdominally, and hematoma formation at the access
site. Rare delayed complications have been reported; for example, the infarcted fibroids may be expelled through the cervix
up to a year later, requiring readmission to the hospital for pain control.12 Infectious complications can also result in readmission to the hospital for antibiotics, and represent particularly difficult
cases when subsequent surgical management is required. One study reported a case of septic uterine necrosis after embolization
of a large submucosal fibroid.13 Collateral blood vessels can lead to treatment failure of this method. In one study, only 6% of patients had treatment
failure, 1% of these required subsequent hysterectomy.10
Small case series of successful pregnancies after uterine artery embolization for treatment of fibroids have been reported.14 Further studies are needed to better characterize the risks of this treatment on future pregnancies.
Laparoscopic uterine artery ligation
An alternative to uterine artery embolization is laparoscopic uterine artery ligation. After dissecting the uterine arteries
away from the surrounding structures, the surgeon ligates or cauterizes the vessels. One study that compared uterine artery
embolization to laparoscopic uterine artery ligation for treatment of fibroids found similar efficacy.15 Operative time can be significantly reduced by ligating only the ascending branches of the uterine arteries, thereby obviating
the need for extensive dissection of the ureters.
Hysterectomy
Of course, hysterectomy represents the definitive management of AUB, and over 600,000 operations are performed each year in
the US.16 By examining a particular patient's unique characteristics, a surgeon can choose from several types of hysterectomies
to determine which one will suit his or her patient best. Options include abdominal, vaginal, and laparoscopically-assisted
vaginal hysterectomy, as well as laparoscopic supracervical hysterectomy.
Because of the risks of surgery, a trial of medical management is usually prudent before resorting to this option; a suspected
malignancy is an important exception to the rule. Hysterectomy offers permanent treatment of AUB, and is more effective at
reducing menstrual bleeding than medical therapies, levonorgestrel IUS, or endometrial ablation. However, the procedure is
associated with significantly higher rates of adverse effects than conservative surgery or nonsurgical options. Quality of
life appears similar for the levonorgestrel IUS, endometrial ablation, and hysterectomy. Furthermore, hysterectomy is significantly
more expensive, but cost differences narrow over time due to the need for subsequent operative management in patients initially
treated conservatively.5,17
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