Hysteroscopic Lysis of Intrauterine Adhesions

Scissors vs. Heat

Since the introduction of hysteroscopy to treat intrauterine adhesions, the prognosis has gone from dismal to excellent. Hysteroscopic management not only enables us to cut all the scar tissue, but it ensures that we will not damage adjacent normal endometrium. There is no justification today for treating Asherman's syndrome by a technique other than hysteroscopy.

Although comparative studies are not available, we advocate that only scissors be used to cut adhesions, and we use them in our own practice.

Adhesiolysis methods that use a resectoscope, an Nd:YAG laser, or a monopolar or bipolar electrode have their proponents. However, all of these modalities deliver energy to the endometrial surface and can cause further damage to the endometrium. Remember that these same instruments are used to cause endometrial ablation.

Years ago, it was demonstrated that—in contrast to what occurs after a scalpel has been used to make an incision—tissue damage is observed far from the operative site when electrodes or an Nd:YAG laser is used for the same purpose. These energy sources offer no advantage—neither speed nor improved hemostasis (intrauterine scars do not bleed, but myometrium does)—over scissor dissection. In a patient with a damaged endometrium, it is prudent to limit the risk of further injury.

Although I have performed surgery that was not successful, it was not because of the inability of the flexible or semirigid scissors to cut through dense scars.

For women with extensive scarring, we should use simultaneous laparoscopy to reduce the risk of uterine perforation. This group of patients is increasing in relative frequency. The main antecedent factors for severe disease are the postpartum curettage performed 2–4 weeks after delivery, and scarring after myomectomy or metroplasty.

After the cutting of all adhesions under direct vision using hysteroscopy, I advise the placement of a splint into the uterus to help reduce adhesion reformation, and the prescription of 1–2 months of high-dose estrogen treatment to promote healing of the tissue and overgrowth of the endometrium.

We use the Cook balloon uterine stent, which has a triangular shape and therefore conforms to the shape of the normal uterus. (See photo, page 36.) This configuration allows it to reduce the risk of reformation of adhesions that had been along the margins of the cavity.

If the adhesions are limited to the endocervical canal and lower uterine segment, a Foley catheter is used as a stent instead of the Cook device because the former has a much wider diameter.

If a Foley catheter is used, the portion distal to the balloon is removed prior to insertion. After insertion of the Foley and inflation of its balloon, ligatures of No. 1 silk are placed around the catheter close to the cervix. This step keeps the balloon inflated and allows the trailing edge to be removed, thereby reducing patient discomfort.

The stent remains in place for 5 days to 3 weeks, depending on the type of stent used and the location and density of the adhesions. During the time that the stent is in situ, a broad-spectrum antibiotic is prescribed.

Following surgery, high-dose estrogen therapy (usually 3–4 mg of micronized oral estradiol) is prescribed for 30–60 days in order to maximally stimulate the endometrium, especially those areas under and adjacent to the adhesions. On the last 5 days of estrogen treatment, 10 mg of medroxyprogesterone acetate is added.

After the menstrual period that follows cessation of the estrogen-progestin treatment, we must perform HSG, hysteroscopy, or a saline-infusion sonogram to assess thoroughly the structure and configuration of the uterus. The last step in postoperative surveillance is a midcycle ultrasound to check endometrial growth and development.

The importance of verifying the normalcy of the uterine cavity and the complete resolution of adhesions before permitting conception cannot be overemphasized. The prognosis for the patient whose problem has been only partially solved is not good.

Variable Success, Mitigating Risks

The rates of cure of Asherman's syndrome vary dramatically according to the antecedent factors involved. In women with Asherman's syndrome that occurs after a D&C for a first-trimester abortion, whether spontaneous or induced, we can achieve a 98% structural success rate (normal follow-up HSG and ultrasound). This rate drops to 50% for Asherman's that occurs after a D&C for postpartum hemorrhage that is performed 2–4 weeks after delivery. The success rate drops further—to 20%—for treatment of scarring that follows myomectomy.

The low success rate of treatment for Asherman's after myomectomy is especially disconcerting because these cases make up an increasing proportion of all those with intrauterine adhesions that we see today. As women delay childbearing, there are more who will develop myomas prior to seeking their first pregnancy at an age older than 35 years.