Chapter 8 – Surgical Management of Uterine Myomas

Chapter 8 Surgical Management of Uterine Myomas

John C. Petrozza

In women of reproductive age, fibroids are known to cause menorrhagia [1], infertility [2], adverse obstetrical outcomes, dyspareunia [3], and, if the fibroids are large, bladder and bowel symptoms, back pain, pelvic pressure or pain, and ureteral compression along with hydronephrosis [4]. The goal of the reproductive surgeon, in regard to symptomatic uterine fibroids, is quite simple: make the uterus normal. By doing this, you alleviate the patients of their symptoms, reduce the risk for fibroid recurrence, and provide an opportunity for the woman to carry a pregnancy to term. The goal of this chapter is to help you determine when to offer a myomectomy, how to prepare for the surgery, and the surgical techniques needed to be successful.

8.1 Diagnosis

Imaging is the cornerstone of helping to characterize the nature of the uterus, determine if any masses are present, and helping to guide any additional tests. Typically, a pelvic ultrasound is arranged as the first-line test, as it is 95–100% sensitive in detecting fibroids and is quite cost-effective, especially when the fibroids are small and the size of the uterus is less than 10 weeks [5]. However, when the fibroids are large or the uterus starts to expand beyond the pelvic brim, the ability to ascertain the number and location of the fibroids becomes more difficult. In addition, the presence of an ovarian cyst should be factored into surgical planning. Of course, if the size of the uterus and fibroids dictates that an abdominal approach is the best option to remove the fibroids, or a hysterectomy is chosen, then there is probably no need for further imaging, except when there is a question of adenomyosis versus fibroids, whereby magnetic resonance imaging (MRI) may help differentiate these a little better.

A sonohysterogram or saline infusion sonohysterography helps in determining whether the fibroid is abutting or encroaching into the endometrial cavity and is more superior to just an ultrasound or hysteroscopy in determining the amount of fibroid intracavitary versus intramural (Figure 8.1). Compared to hysteroscopy, a sonohysterogram allows you to actually measure the size of the fibroids.

Figure 8.1 Sonohysterogram of type 0 submucosal fibroid and endometrial polyp.

MRI, while more costly than an ultrasound or sonohysterogram, is really the best tool to accurately determine the size and location of all uterine fibroids (Figure 8.2).

Figure 8.2 MRI (sagittal) views of fibroid uterus. Uterus A is amenable to laparoscopy. Uterus B is more appropriate for an abdominal approach.

By looking at the sagittal and coronal images, you can develop a map of the fibroids and determine the best surgical approach to normalize the uterus, especially if you are contemplating a laparoscopic approach [6]. Just as important, MRI images are much easier to interpret than ultrasound images, especially for the patient, which ultimately helps involve the patient in the decision-making process. In addition to mapping the fibroids, MRI images can be used to assess whether the fibroid is degenerating or calcified, and can help raise concern for a sarcoma if the fibroid edges are irregular, lymphadenopathy is present, peritoneal excrescences are seen, or if diffusion studies suggest hypercellularity within the fibroids [7].

8.2 Preoperative Evaluation

In addition to a thorough medical history, especially one that looks for a family history of bleeding disorders or diseases that may predispose the patient to a higher risk for sarcoma or endometrial cancer, medications that may predispose to intraoperative bleeding, or other comorbidities that may impact the safety of the surgery or prolong the recovery, thorough pelvic and abdominal exams are mandatory. A bimanual, even if the uterus is large, can help you gauge the presence of any lower-uterine-segment fibroids. During the bimanual exam, it is important to determine if there will be enough lateral space to place your ports. This is the time when you start to think about port placement, if you are considering a laparoscopic approach.

An assessment of complete blood count (CBC) and thyroid-stimulating hormone (TSH) level should have been done at the initial visit and addressed if abnormal. For women older than the age of 35 who have risk factors for endometrial cancer (unopposed estrogen, polycystic ovarian syndrome, obesity, Lynch syndrome, Cowden syndrome, Tamoxifen therapy) it is not unwise to consider an endometrial biopsy for reassurance [8]. All women older than the age of 45 with abnormal bleeding and fibroids should also have an endometrial sampling done [9].

Perhaps the most important thing to do prior to the surgery is review the imaging studies. If there are multiple fibroids and an MRI was done, review the images with your surgical team. Create an expectation of how many fibroids you are expecting to remove and where you might have some difficulties during the case. Like an athlete “visualizes” before their race or game, the surgeon should have a mental picture of what they expect to see and what they will do if they encounter certain situations.

If the patient is anemic due to blood loss, reducing blood with a GnRH agonist, oral contraceptives, or tranexamic acid may be helpful [10]. In addition, oral or intravenous iron supplements may be of benefit. In some case, and after consultation with a hematologist, erythropoietin-stimulating agents may be indicated or even blood transfusion. Consider having intraoperative blood salvage if you expect extensive blood loss or if the patient refuses any possibility of blood product use [11].

Shrinking the fibroids prior to a myomectomy or hysterectomy is sometimes helpful, especially for abdominal cases where you can potentially increase the chances of elevating the uterus through a Pfannensteil incision and avoid the need for a vertical one, or in hysterectomy cases where you can potentially decrease the uterine size to one that is manageable laparoscopically or perhaps increase the odds of extracting the uterus and fibroids vaginally. GnRH agonists will decrease fibroid volume up to 40% over a three-month period, as will aromatase inhibitors, progesterone receptor modulators, and GnRH antagonists [12]. None are Food and Drug Administration (FDA) approved for this purpose.

8.3 Surgical Approach for Myomectomy

There are many variables that must be considered when determining the best approach for a myomectomy.

  1. 1. Size of the uterus.

  2. 2. Number of fibroids.

  3. 3. Location of fibroids.

  4. 4. Surgeon skill.

  5. 5. Prior pelvic and abdominal surgeries.

  6. 6. Patient preference.

  7. 7. Patient’s body habitus.

Ultimately, the approach should offer the best opportunity to remove all fibroids and ensure a healthy, normal uterus. For women who are trying or hope to conceive in the future, I have yet to have a patient who successfully conceived after an open myomectomy complain that we did not perform her surgery laparoscopically. Alternatively, I see many patients in my fibroid clinic for second opinions who present with a recurrence of fibroids, when in reality, after reviewing prior imaging and operative notes, their “recurrence” is actually fibroids that were never removed in the first place. Indeed, 27–62% of women will have myomas seen on ultrasound 5–10 years after their initial surgery and 10–25% will require a second surgery [13,14]. Typically, the larger the uterus and the more numerous the fibroids, the greater the risk.

For a laparoscopic myomectomy to be efficient, there needs to be enough room to place your ports, apply traction and torque to your instruments, and enough distance between your camera and the fibroids. Once a uterus gets above 16 weeks’ size, the case becomes more difficult. Pedunculated fibroids are easy to tackle, as are most subserosal fibroids. Anterior fibroids are generally more approachable than posterior fibroids, except when they start to encroach near the bladder. The more fibroids there are, the longer it will take to remove them, suture, and extract the tissue. There are few data to help us determine what size or number of fibroids should be used to decide one approach over the other. Fibroids that were associated with major complications included myomas greater than 5.0 cm, greater than three myomas removed, broad ligament fibroids, and intramural fibroids [15]. As technology has become better (flexible laparoscopes, high-definition cameras and monitors, barbed suture, etc.) and surgeons better trained, these parameters have changed. In our practice we feel comfortable approaching cases with fibroids greater than 10 cm or more than seven fibroids.

Perhaps the biggest limiting factor, at least in our hands, for a laparoscopic approach are cases where there are significant submucosal involvement either from one large fibroid or multiple smaller ones. Also, cases where there are multiple intramural fibroids that will not be easily seen or felt during the laparoscopy usually forces me to recommend an abdominal approach.

Robotic-assisted laparoscopic myomectomy or hysterectomy is much more time-consuming and expensive compared to traditional laparoscopy, with no clear improvement in outcomes, based on very limited studies [16]. However, its true advantage lies in its ability to make laparoscopy easier for the general gynecologist, hopefully allowing for more appropriate laparoscopic procedures to be done.

Overall, laparoscopy allows for a shorter recovery and lower overall risk for complications compared to abdominal myomectomy and should always be considered. But never hesitate to do an open procedure if it will ensure an efficient procedure and the best opportunity to remove all fibroids and normalize the uterus.

8.4 Techniques

Although the entry approach is different for a laparoscopic versus an open approach, once the surgeon begins removing the fibroids, the basic principles remain:

  1. 1. Employ techniques to minimize blood loss.

  2. 2. Minimize tissue injury.

  3. 3. Identify the fibroids pseudocapsule.

  4. 4. Use countertraction on the fibroid and sharp dissection to help you stay within the pseudocapsule as you isolate the fibroid.

  5. 5. Close all dead space in the remaining defect, suturing in layers if needed.

  6. 6. Achieve hemostasis.

  7. 7. Close the serosa using the least reactive method and suture possible to minimize adhesion formation.

  8. 8. Use some form of adhesion barrier over the myomectomy sites.

  9. 9. Extract the tissue from the body using an efficient technique that minimizes tissue dispersion.

Minimizing blood loss during incision into the fibroid is important, yet none of the pharmacologic or mechanical techniques alone have been shown to reduce the rate of blood transfusion. Likewise, there are few data looking at combinations of pharmacologic and mechanical devices. Vasopressin is the most commonly used pharmacologic agent and randomized studies have shown that blood loss is less when compared to placebo and comparable or less when compared to a uterine artery tourniquet [17,18]. Of course, it is easy to inject vasopressin via laparoscopy or an open procedure, but it is technically difficult to place a uterine artery tourniquet laparoscopically, and thus it is rarely used with this approach. Vasopressin comes in 20-unit vials and is often diluted, typically 20 units in 100 ml of saline. The half-life of an intramuscular injection is 10–20 minutes and the duration of action is 2–8 hours. The maximum safe dose is not known, but some studies suggest no more than six units should be used [19]. It is contraindicated in women with cardiovascular, vascular, and renal disease. We try to avoid injecting directly into the myometrium, but rather inject just under the serosa, allowing the superficial venous system to take the medicine into the deeper layers. This also helps avoid an intravascular injection. Vasopressin should be injected before each uterine incision. Instead of injecting into multiple sites, injecting into one site near your anticipated incision line should be adequate (Figure 8.3). If more vasopressin is needed, keep your needle in place and just switch out your syringe.

Figure 8.3 Injecting vasopressin under serosa.

A uterine artery tourniquet is more suited for an open myomectomy. Make a small 1.0 cm incision in the broad ligament just above the uterocervical junction. Take care to find a clear area away from the uterus. Use a ¾-inch Penrose drain or similar catheter and pass behind the uterus and through the incisions, tightening and securing the ends anteriorly with a Kelly clamp. Avoid applying too much tension, as you may tear the broad ligament and uterine artery or vein. The goal is to compress the vessels and reduce blood flow [20].

Occlusion of the ovarian arteries is best accomplished by placing an atraumatic clamp, such as a bulldog clamp, bilaterally across the uterine ovarian ligament. There are laparoscopic bulldog clamps that can be detached from the end of their laparoscopic introducer and retrieved very easily with the same device.

Intraoperative blood salvage is a great ancillary tool to use, especially if you are anticipating blood losses that would warrant a transfusion based on the patients starting blood count. The goal is to avoid a blood transfusion. Utilizing the machine because you anticipate a 500 cc blood loss in a patient with a hematocrit of 42% is not cost effective or clinically meaningful. However, having it available for a patient with a hematocrit of 30% where you anticipate a blood loss greater than 500 cc may be more realistic. Blood loss is generally more pronounced when many fibroids are removed, especially those that are intramural and deeply penetrating the myometrium, as well as the length of the surgery [21].

In cases where extensive bleeding is encountered, in a last-ditch effort to save the uterus, uterine artery ligation or uterine artery embolization may be employed. Uterine artery embolization is best done in these cases with an absorbable media such as Gelfoam®, as the impact of using more permanent occlusive particles on fertility and pregnancy are not well known [22].

Gentle tissue handling is just as important in laparoscopic surgery as it is in an open case, perhaps even more so. Due to the cooling and drying effect of the CO2 gas insufflation, the tissue may be more prone to desiccation and more traumatized by pressure and pulling than what it is exposed to in open gases. Every attempt should be made to avoid grasping and pulling on the serosal surface (Figure 8.4) and the use of warm, humidified CO2 gas has been advocated to avoid tissue damage and reduce post-operative pain.

Figure 8.4 Avoid excessive serosal damage. Note that Allis grasper is holding myometrium and not serosa.

Minimizing tissue damage also means using thermal energy that has the least amount of dispersion. Most often this is a monopolar device with a needle tip, an ultrasonic device, or a CO2 laser. In open cases, you can even use a scalpel, although we favor a monopolar needle tip on a cutting mode for open cases and an ultrasonic device for laparoscopic cases (Figure 8.5).

Figure 8.5 Minimize thermal damage. An ultrasonic device is used to make uterine incision.

The ultimate key to a myomectomy, the one step that will help minimize blood loss, is to find the myoma’s pseudocapsule. The pseudocapsule is a compressed layer of myometrium that is relatively avascular. Just above this plane, however, is a very vascular myometrial layer that bleeds quite easily. While this seems quite intuitive, in practice there are times where it is difficult to discern the perfect plane. Prior use of GnRH agonists, prior uterine myomectomies, the presence of coexisting adenomyosis, and degenerating fibroids can all distort the pseudocapsule [23]. More importantly, a malignancy can also do this. If you have difficulty finding the pseudocapsule and there is no other reason to explain a distorted tissue plane, send off a sample of the mass for a frozen section analysis. Although a frozen section is not definitive, any ambiguous or positive result warrants an open procedure. It is better to cut deep into the fibroid and work back to find the pseudocapsule rather than cutting too shallow and digging through myometrium to find the right plane (Figure 8.6).

Figure 8.6 Uterus A incision is not deep enough. Uterus B incision has reached myoma and pseudocapsule is exposed.

Once you identify the plane, make sure your incision is large enough to remove the fibroid. If the incision is not large enough, it will be easy to drift from the appropriate tissue plane and you will be applying too much force on the myometrium and serosa as you try to create better exposure. You know you have made the appropriate incision when you start to see the fibroid deliver itself as you dissect it out (Figure 8.7).

Figure 8.7 Incision is large enough that myoma starts to extrude itself with minimal countertraction.

A myoma screw, single-tooth tenaculum, sharp towel clamp, or triple hook clamp should be used to grab the fibroid and provide countertraction (Figure 8.8).

Figure 8.8 Countertraction with tenaculum helps define fibers that need to be released. The yellow arrow shows the fibers that need to be released. Avoid cutting too far down (red arrow) as you’ll get into myometrium and bleeding.

This facilitates identifying the fibers of the pseudocapsule that cling to the fibroid. Sharp dissection will facilitate cutting these fibers. When dissecting, stay above the developing groove and focus on loosening the loose fibers. Some clinicians advocate using the end of a scalpel of insert their fingers or a sponge stick to help pull down these fibers. I discourage this as it tends to traumatize the myometrium more and distorts your planes. As the dissection gets further into the tissue plane, pull the serosa back and grab the knuckle of tissue that forms above the dissection area with an Allis clamp (Figure 8.9). This will keep you from tearing the serosa and provide better exposure.

Figure 8.9 Allis clamp holds on to knuckle of pseudocapsule and myometrium to help define tissue plane.

Fibroids that are just below an enucleated fibroid should be removed through the same incision. However, it can be argued that fibroids that are more lateral and less accessible should be removed through a separate incision. This may prevent causing more damage to the myometrium and reduce the risk of an inadvertent entry into the uterine cavity.

If there is concern that you may enter the cavity, instilling some methylene blue dye into the cavity at the start of the case will aid in identifying the cavity and facilitate a proper repair. If the cavity is entered, there is no need to identify the endometrium and reapproximate it with suture (Figure 8.10).

Figure 8.10 Methylene blue dye indicates cavity has been entered.

The inadvertent suture in the uterine cavity will predispose for adhesions. Instead, reapproximate the myometrium above the endometrium, which will bring the endometrium together with less risk of placing an inadvertent stitch into the uterine cavity. It is best to close each defect once the fibroid(s) from that incision is removed. This will help minimize blood loss. Following the general principles of surgery, you want to completely close the dead space within the uterine defect. Typically a braided polyglactin (Vicryl®) suture is used or a barbed suture is employed. The benefit of the barbed suture is that it applies an even tension along the suture line and keeps the tissue well-approximated. It also does not require tying a knot, which is helpful when suturing laparoscopically. The sutures can be placed interrupted, figure-of-eights, or running. Avoid locking your suture line, as this may cause tissue necrosis and promote poor healing. Use as many layers as you need to close the dead space and to reduce any tension for your serosal closure (Figure 8.11).

Figure 8.11 Closing defect in layers using barbed suture.

The serosa is typically closed with a monofilament suture, such as 3-0 or 4-0 PDS. There are no data showing that a baseball stitch prevents adhesion formation any better than a simple running stitch, but intuitively, it makes more sense that hiding as much suture below the serosa exposes less foreign material and perhaps results in less adhesion formation (Figure 8.12). Following that principle, closing the serosa in a manner similar to a subcuticular stitch may be more appealing.

Oct 26, 2020 | Posted by in OBSTETRICS | Comments Off on Chapter 8 – Surgical Management of Uterine Myomas
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