Charles J. Ascher-Walsh, Michael Brodman; Edited by Elizabeth Buescher, Camran Nezhat
Leiomyomas, or fibroids as they are commonly called, are benign tumors of the myometrium surrounded by a pseudocapsule. They typically arise from a single mitotic event and cause a myriad of problems including menorrhagia, infertility, and pain. They are extremely common, found in over half of women over age 50. Traditionally, symptomatic submucous fibroids were treated with either hysterectomy, if the patient no longer desired fertility, or open myomectomy if the patient wanted to preserve her fertility. However, with the introduction of the hysteroscope for the treatment of uterine fibroids, women have been able to have submucous myomas resected without invasive surgery. Over the last several decades, technology has made significant advances in the areas of lighting, electocautery, electrosurgery, and metal design, resulting in a enhanced ability for the gynecologic surgeon to diagnose and treat fibroids.
Hysteroscopic myomectomy has classically been performed with an instrument called a resectoscope. Newer therapies use other instrumentation and are discussed in a later section; however, the bulk of hysteroscopic myomectomies performed today continue to be done using the resectoscope. Gynecology borrowed this technology from urology. Before Neuwirth and Amin1 reported the first case of using a resectoscope for the treatment of a submucosal myoma in 1976, urologists had been using the device for decades.
The development of the resectoscope resulted from scientific advancement in a variety of fields. Current resectoscopes require a light source to be able to see the pathology, a fenestrated sheath to reach the pathology both visually and with instrumentation, and an electric cutting source to resect the pathology. After Thomas Edison invented the incandescent lamp in 1879, it was just over 20 years before Reinhold Wappler and William Otis presented the first American-made cystoscope to the American Association for Genito-Urinary surgeons in 1900.2
By 1926, advances in technology allowed Bumpus to describe what would be seen as the earliest predecessor to our current resectoscope. He combined a cylindrical knife attached to a high-frequency current designed for coagulation with a fenestrated sheath and light source. The combination of these components for transurethral resection of the hypertrophied prostate was the basis for all future designs. In that same year, the first reported case describing the use of a device described as a “resectoscope” was published by Maximilian Stern3. His device consisted of an insulated shaft in which was placed a 0.5-cm tungsten cutting loop attached to an electrical current. The loop was situated at a right angle to the shaft and placed over the defect in the shaft at the distal end. This end was placed over the prostate, and the loop was moved away from and toward the viewer to cut the hypertrophied tissue.
The first report of the use of electrosurgery in humans came from the French physicist d’Arsonval.4 He demonstrated in 1893 that using alternative currents of 2 kHz to 2 MHz caused tissue heating and cutting without muscle or nerve stimulation. Surgeons began to use electrosurgical techniques while performing a variety of surgeries. At the same time Stern was developing his resectoscope, William T. Bovie developed an electrosurgical unit for tissue cautery that was first used by Harvey Cushing on October 1, 1926, at the Peter Bent Brigham Hospital in Boston to remove a vascular myeloma.5 Joseph McCarthy took advantage of this new technology by modifying the resectoscope to include a magnifying lens and improved insulation of the sheath. He reported these advances and the instrument’s use in the New England Journal of Medicine in 1932.6
Iglesias and his colleagues7 further modified the resectoscope to a model that urologists and gynecologists continue to use today. They added a second sheath around the current design that allowed for a separate outflow tract. This allowed for continuous irrigation, which allowed the procedure to be performed with less bladder pressure. The constant flow also resulted in better visualization. They reported on this in 1975, and within a year, Neuwirth and Amin1 were reporting on its use for resecting a submucosal myoma. It was the addition of the outflow tract that allowed its use for this purpose. However, the real in gynecologic surgery was the development and introduction of videoendoscopy by Camran Nezhat in the late 1970’s and 1980’s that transformed hysteroscopic surgery from a one-man band into an orchestra, allowing the participation of other members of the team8.
As indicated above, the modern gynecologic hysteroscope is based on the urologic resectoscope, with a key difference: the gynecologic resectoscope employs a blunter distal end. The authors of this chapter assume that the readers have a basic understanding of the modern hysteroscope as it is used today. Therefore, we will only present a brief overview of the modern instrument.
One common point of confusion is the difference between a resectoscope and hysteroscope. A hysteroscope is a sheath with light and optic fibers that are introduced through the uterus through the cervix allowing for video display of the uterine cavity. Once the hysteroscope is introduced into the uterine cavity, a distention media is used to expand the cavity to allow for visualization. More advanced operative hysteroscopes also include a channel through which instruments can be passed, such as graspers or scissors, to operate on the pathology that is revealed by the hysteroscope. The operative hysteroscopes are of a greater diameter than the purely diagnostic hysteroscopes. The resectoscope (or hysteroscopic resectoscope) allows the entry of an electrode that can be used to operate on intraunterine pathologic, such as to shave off a fibroid. Therefore, it is the modern resectoscope that will be the focus of this chapter.
There are two types of current that can be used in the resectoscope: monopolar and bipolar. For the monopolar electrode, current flows from the active electrode at the end of the resectoscope to the passive electrode. In order for the current to flow, a non-conductive media must be used, such as sorbitol or glycine. With the bipolar system, both electrodes are in the electrosurgical loop. Obviously, this is much safer as the current only passes through that tissue with which the electrode comes into contact. In this setting, conducting distention media can be used safely. 9
The standard resectoscope comes in a variety of sizes, typically between 24F and 28F. These resectoscopes all use a 4-mm telescope and have separated outflow and inflow sheaths. There are smaller resectoscopes with 3-mm telescopes, but these are not well suited for resecting submucosal myomas and are more appropriate for polyps or intrauterine adhesions. The telescopes vary from 0 to 30 degrees, depending on operator preference. The 12-degree telescope seems to be best suited for resection of a myoma because it allows for the best continuous visualization of the electrode. In the 0-degree scope, the electrode may impair a significant part of the visual field; in the 30-degree scope, the electrode may extend beyond the visual field. The 12-degree telescope allows for complete visualization of the electrode through its entire range of motion while having only a small amount of visual field obstruction. Depending on the brand, the telescopes have a panoramic field of vision between 70 degrees and 120 degrees. The focus is set to infinity, which magnifies objects more the closer they are to the lens. The telescopes are designed to provide the best visualization 30mm to 35mm from the lens. Operators should try a variety of instruments to determine which one they find most appropriate for each situation.
The sheaths have fenestrations to allow for different tracts for the camera, electrode, inflow distention medium, and outflow medium. The distention medium flows in through the inner sheath. On some devices, this is the port most proximal to the eyepiece. Others have the inflow and outflow at the same distance from the eyepiece. For these devices, the inflow is found on the same side of the device as the attachment for the electric cable. It is important to attach the inflow and the outflow correctly because there is more resistance in the outflow sheath. This increased resistance allows for the distention of the uterine cavity. The increased pressure from the distended uterine cavity results in equilibrium between the inflow and outflow tracts. The open cavity and continuous movement of fluid allow for better visualization of the uterine cavity and potential pathology within it.
The distention fluid is discussed in another section; herein, we discuss the devices used to instill and monitor the fluid, which are equally as important as the fluid itself. A variety of devices are available, from those as simple as a hand pump to provide enough force to push the fluid in and provide a distended cavity, to complex pressure devices that vary inflow to provide and maintain the specific intrauterine pressures and collect the outflow fluid to monitor fluid deficiency. The hand pump is typically much less expensive than the fluid monitoring units. It allows the surgeon to control the inflow of fluid, allowing for a rapid change in flow to correct poor visibility due to a lack of distention or to fluid clouded by blood. However, use of a hand pump relies on the surgeon not to overdistend the cavity, which may lead to a more rapid absorption of the distention medium. Because hypotonic distention medium is the most common type of medium used, a fluid imbalance may lead to serious sequelae from hyponatremia, including death. Hysteroscopic myomectomy will frequently require a significant amount of time to complete, making the fluid balance an important issue. Surgeons considering new equipment for hysteroscopy should seriously consider some of the newer devices that allow closer monitoring of fluid deficits so as to decrease the risks to their patients. Surgeons using older devices need to be aware of these risks and to adjust their setups and techniques to minimize these risks, for example, using drapes that have fluid-collecting pockets that are placed under the buttocks so that fluid is not lost onto the floor or using floor suction devices that can minimize the amount of fluid not accounted for during the procedure.
The electrode most frequently used for the hysteroscopic myomectomies is the loop electrode. Electrodes also come in other types, for example, the roller ball, barrel, and point electrodes used for a variety of procedures, including endometrial ablation, removal of adhesions and polyps, and resection of a uterine septum. The loop electrodes have versions in which the loop is situated at angles of 0, 45, 90, and 120 degrees from the shaft. The most commonly used electrode for myomectomies is the 90-degree loop.
The electrodes are attached to a high-frequency electrosurgical unit preferably with a digital wattage indicator, such as the commonly used unit from Valleylab called the Valleylab Return Electrode Monitoring Circuit (Tyco, Boulder, CO). The most commonly used current for the hysteroscopic myomectomy is monopolar. The Versa Point unit by Gynecare is a bipolar unit and is discussed in the section on newer devices. A monopolar current in electrosurgery is an alternating radiofrequency current that runs from the generator through the electrode to the surgical site. Because the surgical site does not conduct the current as well as the electrode does, it is rapidly heated, and cutting and coagulation are accomplished by this method. The current is then dispersed throughout the body so that it loses any power within a few millimeters of the electrode. It is again collected at the grounding pad and returned to the generator, which completes the electrical circuit. Most electrical units offer a cutting or coagulation current or a blend of the two. The electrical current is represented by a sinusoidal waveform. A cutting wave is a continuous wave, whereas a coagulation wave is made up of intermittent bursts. The power of the waveform, measured in watts, is determined by the voltage and the time delivered. Because coagulation waveforms are intermittent and hence have an actual current only 25% of the time, equal voltage peaks in cutting and coagulation currents result in a lower wattage for the coagulation current. To achieve equal wattage, that is, setting the generator on equal settings for both cutting and coagulation currents, the voltage peaks must be significantly higher in the coagulation current. With higher voltage peaks, the force behind the flow of electrodes, although intermittent in the case of coagulation, is higher and the electrons can be driven deeper into the tissue. This makes the use of the coagulation current slightly more dangerous as the thermal spread of the tissue destruction is greater.
Tissue is transsected by the intracellular fluid being rapidly heated to the point at which the cell is literally vaporized. As the cell is torn apart by vaporization, the tissue is cut. The continuous waveform is better at creating this vaporization than is the intermittent coagulation waveform. The intermittent current results in a slower heating of cells. Depending on the type of cell being treated, the coagulation waveform may still be used to cut tissue, especially if it is moved quickly through the tissue, although it is more likely to slowly desiccate and fulgurate the tissue, eventually leading to carbonization. Intracellular fluid is a good medium for conducting electricity, so when the fluid is vaporized by the cutting current, the low peak voltage is not able to drive the current further into the tissue. The intermittent coagulation current heats the cell more slowly; therefore, the water in the cells does not flash into steam. The cells are dehydrated more slowly. The higher peak current of the coagulation current allows it to be driven further into the tissue, continuing to heat the tissue until only the carbon is remaining. It is for this reason that the cutting current allows for an easier and safer removal of submucosal myomas. The electrode tends to pass through the tissue with less resistance, and there is less risk of thermal spread, which is important as one approaches the uterine serosa during the removal of larger myomas.
Recently, laser has also been used in hysteroscopic surgery. A variety of laser types have been used, including argon, krypton, and neodymium-yttrium-aluminum-garnet (Nd:yAG). Although all of these are adequate, the most widespread use has been with the Nd:yAG laser. This can be used in both the “touch” and “no touch” technique in hysteroscopic myomectomy. In the “touch” technique, there is direct contact between the laser fiber and the tissue. This contrasts with the “no touch” technique in which the laser fiber remains a few millimeters from the surface of the tissue. Myomas measuring 2cm or less can be effectively treated with the laser.9
New instruments and innovations are always being added to the hysteroscope. For the gynecologic surgeon, it is best to stay abreast of new technologies and incorporate those that help strengthen surgical technique and increase the application of hysteroscopic myomectomy to a greater number of patients in a safe environment. Appropriate training in any instrument is essential for proper, safe use.
As alluded above, the uterine cavity is a potential space and hence requires some type of medium to distend it so that surgery can be performed. Because of the vascular nature of the uterus, the media used to distend the cavity may be absorbed. The higher the pressure used for distention, the greater the media absorption. It is therefore important to choose the best medium for the job at hand. The perfect substance would be isotonic and have little impact on fluid volumes in the body. Its absorption would not cause electrolyte abnormalities. It would allow for good visualization. It would not cause hemolysis and would not conduct electricity. It would also allow for easy cleaning of the instruments after use, and the fluid itself would be inexpensive to use. This perfect medium does not exist; however, and one must weigh the risks and benefits of available media when choosing which one to use for each procedure.
The following media have been used for uterine distention: carbon dioxide, Hyskon, Ringer's lactate (RL), normal saline (NS), half normal saline, glycine, sorbitol, mannitol, Cytal (sorbitol and mannitol), and dextrose 5% in water (DW). For our purpose, the discussion is limited to fluid that is suited for the resectoscope. RL and NS contain electrolytes and are conductive. The current diffuses in every direction away from the electrodes, and no cutting effect is found. They are therefore not suited for the resectoscope. DW and water are nonconductive; however, they are rapidly absorbed and can lead quickly to a dangerous state of hyponatremia. Hyskon is an electrolyte-free solution with extremely high viscosity. It is composed of dextran 70 in 10% dextrose. It is very thick and slowly absorbed. The high viscosity makes it very difficult to use in the continuous-flow resectoscope currently available. More importantly, unless meticulously cared for, Hyskon left in hysteroscopes and resectoscopes can quickly ruin the equipment. Because of this latter problem, most surgeons have found it too costly to continue its use.
Glycine is the fluid most commonly used in resectoscopic surgery today. It has also been the most commonly used fluid by urologists. The fluid is 1.5% of the amino acid in water. It is a hypotonic fluid, having an osmolality of 200 mOSM/L.10 This osmolality causes minimal hemolysis but may cause significant hyponatremia and fluid overload. Glycine has also been found to provide excellent visualization of the uterine cavity.11 Lysine is metabolized to ammonia and glyoxylic acid in the liver and kidney. The ammonia is excreted as urea, and the glyoxylic acid is further reduced to oxalate and excreted by the kidneys. Glcsine’s plasma half-life is approximately eighty-five minutes. Surgeons frequently check intraoperative or immediately postoperative serum sodium levels for confirmation of sodium level. This problem may be worsening; however, as the glycine is metabolized and should therefore be rechecked at least an hour after the procedure.
Sorbitol and mannitol are sugar solutions with similar chemical characteristics, although they are broken down in different ways. They are both nonconducting fluids that are good for visualization and use in continuous-flow devices. Both are hypotonic and, like glycine, may cause fluid overload and hyponatremia with excessive absorption. Whereas sorbitol is broken down to glucose and fructose, mannitol remains mostly unmetabolized. Mannitol is excreted quickly by the kidney and acts as a diuretic, counteracting the hyponatremia and fluid overload. As a medium, it may be the best suited for the resectoscope, although mannitol alone has a higher viscosity so may be slightly more difficult to work with.
In most resectoscope cases glycine is used as the distention fluid. Given the risks of hyponatremia and fluid overload, it is important to understand the mechanism of distension as well as the complications that are caused by hyponatremia and the way in which it is treated. Fluid absorption is related to a number of factors within the uterus. Fluid is absorbed through the vasculature of the uterus. The greater the uterine pressure, the higher the rate of fluid absorption. Visualization adequate for surgery can usually be achieved with pressure between 75mm Hg and 100mm Hg. Any additional pressure will usually not add to visibility but will only increase the rate of fluid absorption. In low-tech units that do not incorporate the monitoring of fluid pressure, placing a bag of low-viscosity fluid 1m above the supine patient will result in a pressure of 73mm Hg, whereas placing it 1.5m above the patient will increase the pressure to 110mm Hg.12 Hand pumps can significantly increase the pressure to values far in excess of what is necessary for appropriate visualization. The best units are those that closely monitor the pressure necessary to inject the fluid and maintain this pressure at levels <100mm Hg. These units should also involve an underbuttock drape to assure total outflow collection and a return system that correctly determines the fluid deficit in a continuous fashion.
Absorption of hypoosmolar low-viscosity fluids such as glycine may lead to fluid overload and hyponatremia, which can potentially result in death of the patient. Continuous monitoring should occur during the case. In general, serum sodium levels decrease by 10 mmol/L for every liter of hypotonic solution absorbed.13 Once a deficit of 1L is reached, the surgeon should begin to conclude the procedure. The deficit should not surpass 1.5L, and once this deficit is approached, the procedure should come to an immediate conclusion. If >1L is lost, the patient should be monitored in the recovery room and serial serum sodium levels should be checked. As glycine or sorbitol is metabolized, serum sodium may continue to fall, even after the completion of the procedure. If the serum sodium level increases after an initial period of observation of at least 30 minutes, and the initial serum sodium was at least 125mmol/L, it is safe to discharge the patient. The highest reported serum sodium that still resulted in cerebellar herniation and death was 121mmol/L.10 The signs and symptoms of hyponatremia include an initial bradycardia and hypertension. The patient may then develop nausea, vomiting, seizures, pulmonary edema, and cardiac abnormalities. Without correction, the final stage is coma and death, usually caused by cerebral edema due to the hypoosmolar state leading to cerebral herniation through the brainstem.
Treatment of hyponatremia should be instituted as soon as it is recognized. Frequently, this simply means stopping the procedure. If significant hyponatremia is suspected, a diuretic such as furosemide should be given immediately. Although chronic hyponatremia is expressly not treated with diuretics, acute hyponatremia, especially in this electrolyte setting, should be treated with furosemide. In addition, sodium levels should be monitored serially. In the setting of severe hyponatremia, that is serum sodium levels <120mOsm/L, central monitoring may be considered to assess the complex changes in hemodynamics that may ensue. Normal saline should be given instead of hypertonic solutions to prevent ensuing hypernatremia. Serum sodium may be increased up to 2mEq/L per hour. Too rapid a correction of hyponatremia may lead to central pontine myelinolysis. Although it is more likely to occur in the correction of chronic hyponatremia, it still is a risk in an acute surgical setting and can be avoided by not using a hypertonic solution or the rapid infusion of normal saline.
PATIENT EVALUATION AND PREPARATION
Fibroids are one of a number of structural abnormalities in the uterus that may cause abnormal bleeding. The list also includes endometrial polyps, endometrial hyperplasia or cancer, and adenomyosis.
Submucous fibroids are classified according to the European Society of Hysteroscopy as: Type 0 (complete intracavitary myoma), Type I (<50% of the myoma contained within the myometrium), or Type II (>50% of the myoma contained within the myometrium).14 The degree of intramural extension is assessed by observing the angle of the fibroid with the endometrium at the attachment to the uterine wall.
Numerous studies are available that attempt to differentiate between the possible causes of abnormal bleeding. The most important first step is a thorough history and physical. A postmenopausal woman or teenager with abnormal bleeding is much less likely to have fibroids as a cause than is a 45-year-old woman with excessive menstruation. The teenager should be evaluated for anovulatory or other hormonal causes of abnormal bleeding, whereas the postmenopausal woman should be evaluated to rule out endometrial cancer. A long history of irregular menses, every 3 months to 4 months that are frequently excessive is more likely to point to a hormonal cause of abnormal bleeding compared with a recent progressive increase in the volume of menstruation in a woman with an enlarged uterus on examination, which more likely indicates myomas as the cause. Although the history and physical may not give an absolute diagnosis for the abnormal uterine bleeding, they often point to the direction of focus to achieve this diagnosis and hence the appropriate treatment.
If a structural abnormality is suspected, ultrasound is usually the modality of choice for the initial evaluation. Ultrasound is very sensitive for the detection of uterine myoma. With the addition of sterile saline injected into the uterine cavity, the positive predictive value (PPV) for the detection of a submucosal lesion is very high. Cepni et al15 found a PPV of 78% to 81%, depending on menstrual status, for submucosal myoma using a saline-infused sonogram (SIS). De Vries et al12 demonstrated an increase in sensitivity in the diagnosis of intracavitary lesions from regular vaginal sonogram to SIS from 60.5% to 88%. By using an SIS, ultrasound can usually differentiate between polyps, myomas, and carcinoma. Ultrasound can also be used to diagnose adenomyosis, although the sensitivity and specificity are not as high. If the diagnosis is in doubt, MRI, although more costly, can better differentiate adenomyosis from other uterine pathology. In addition, it is very useful in determining the size, number, and location of uterine fibroids in preparation for surgery.
Three-dimensional sonography has shown some promise in the diagnosis of submucosal myomas. Salim et al16 demonstrated 75% to 95% specificity in determining the level of involvement in the endometrium. This could aid surgeons in determining whether a patient is a candidate for hysteroscopic resection.
Hysteroscopy is considered the gold standard for diagnosis. It is redundant and adds unnecessary risks to take a patient to the operating room simply to diagnose a submucosal myoma with no immediate plans to resect it. However, the ability to perform in-office, diagnostic hysteroscopy significantly decreases these risks. CO2 is frequently used as the distending medium, and with minimal discomfort, a diagnosis can be made. Because of the significant effort, on the part of both the surgeon's office and the patient, to schedule a case for the operating room and perform the preoperative evaluation required by many hospitals, an in-office hysteroscopy may occasionally save much unnecessary effort and lost time.
Hysterosalpingogram was frequently used in the past to diagnose myomas. Although it is still useful in infertility evaluation and often leads to further workup for myomas, it is not as sensitive and specific as SIS. It is also more invasive, with a higher risk of salpingitis/pelvic inflammatory disease, so is no longer as commonly used to evaluate fibroids alone.
A hysteroscopic myomectomy is most likely to be performed in the case of abnormal uterine bleeding or infertility. Although myomas generally may cause a myriad of symptoms, unless the myoma is causing abnormal bleeding or affecting fertility, a surgeon is usually not justified in performing a procedure that has potential surgical and anesthetic complications. Performing a hysteroscopic resection of a myoma will typically not resolve symptoms related to the bulk of a uterus secondary to myomas. Therefore, an appropriate workup of abnormal uterine bleeding and infertility is necessary before proceeding to surgery. Hysteroscopic myomectomy has been recommended as first-line conservative surgical treatment.17
Abnormal uterine bleeding is a very common problem with a great variety of causes. Before operating for a submucosal myoma, other causes of bleeding must first be explored. Anovulatory bleeding is a common cause of abnormal uterine bleeding. It is frequently found in the perimenarcheal and perimenopausal age groups. Whereas fibroids are extremely unlikely in the former, they are very common in the latter. In fact, the period of most rapid fibroid growth is often during the few years preceding menopause because of the hormonal changes that occur around this time. Without the progestin withdrawal from ovulation, the continuously stimulated endometrium can randomly bleed, occasionally quite excessively. Women with polycystic ovarian syndrome also frequently have abnormal bleeding due to anovulation. Not all submucosal myomas cause abnormal uterine bleeding. In addition, not all submucosal myomas require surgical management. Hence, working up and medically treating other causes are prudent first steps before proceeding to surgery. The complete evaluation for abnormal uterine bleeding is beyond the scope of this section. Causes to assess other than structural ones include bleeding disorders; hormonal causes, such as anovulation; thyroid disease; hypothalamic dysfunction from excessive weight loss; stress; exercise; and foreign bodies, such as an IUD. Patients over 40 years of age or with a history of untreated abnormal uterine bleeding for a period >1 year should have an endometrial biopsy to rule out cancer.
Medical treatment for abnormal uterine bleeding, including that caused by a submucosal myoma, should be considered. Oral contraceptives typically decrease blood loss during menses by 50%.18 Taking oral contraceptives in a continuous fashion frequently may stop menses altogether. Cyclic and continuous progestins may also be used in a similar fashion to decrease menstruation. A progestin-containing IUD usually results in a decrease in menstruation and frequently results in amenorrhea. Unfortunately, however, abnormal bleeding caused by a structural defect, such as a submucosal myoma, frequently does not respond to medical therapy and requires surgery.
Before gynecologists adopted the use of the resectoscope, the vast majority of patients treated surgically for abnormal uterine bleeding proceeded to hysterectomy, usually via laparotomy. They would be subjected to all the potential complications associated with this procedure, including prolonged pain, long hospital stay, and loss of work. The use of the resectoscope changed this significantly for patients with abnormal bleeding due to a submucosal myoma. They are now able to have their problem dealt with in an outpatient setting with significantly less anesthesia and decreased surgical risks. To maximize the chances of success with the procedure; however, the patient and her uterus must be optimized before the procedure.
The general principles of patient optimization before surgery apply to patients who are undergoing resection of a submucosal myoma. Significant anemia should be corrected if possible before proceeding to the operating room to decrease the intraoperative risk of heart attack and stroke and to decrease the need for transfusion and its associated risks. Hormonal therapies, such as oral contraceptive and progestins alone, may decrease the bleeding enough so that the patient may increase her hemoglobin with supplemental iron therapy alone. GnRH agonists are sometimes necessary to stop the menstrual cycle altogether to enable the woman to establish a surgically safe hemoglobin level. Patients with concomitant medical conditions, such as diabetes or thyroid disease, should be medically optimized to decrease the risk of perioperative complications. Patients should be well nourished, well rested, and relatively free of stress when entering any surgical procedure.
The endometrium should preferentially be in the early proliferative phase for any hysteroscopy. The endometrium is thinnest at this point and less likely to hide small lesions. However, it is not always possible to schedule this naturally. Because of the availability of the surgeon and irregular menstrual cycle, it is often necessary to manipulate the menstrual cycle, either with oral contraceptives or progestins. To schedule the procedure with the endometrium in the appropriate state, prolonged progestin treatment, as found in depomedroxyprogesterone acetate, frequently leads to endometrial atrophy, which allows for greater visualization during the procedure. However, the effect is variable and frequently outweighed by the side effects that may coincide with this type of treatment, such as irregular bleeding, bloating, weight gain, decreased libido, and headaches. Oral continuous progestins, such as medroxyprogesterone acetate and norethindrone acetate, may also be used. Although they must be taken on a daily basis, they have the benefit of being able to be stopped at any time if the symptoms become unbearable for the patient.
Because the surgical removal of submucosal myomas is limited by the amount of distention fluid absorbed, it is especially important for the patients with larger myomas, which may require a longer procedure, to be optimally prepared for surgery. This frequently involves the use of GNRH agonists. After administration, there is a brief period of stimulation over the first few days and then a decrease in action of the hypothalamic-pituitary-ovarian axis to a point of senescence. This results in a reversible pseudo-menopausal state with very low levels of both circulating estrogens and progestins. This has multiple effects on the patient and the uterus specifically. Then, it stops menstruation, which allows time for the anemic patient to increase her hemoglobin.
GnRH agonists are best given just before the proliferative phase, preferably from the middle to the end of menstruation. During this period, the initial stimulation has less of a chance to result in an increase in bleeding. If the GnRH agonist is used later in the cycle, it should be given with 7 days of a concomitant progestin to stabilize the endometrium and inhibit further proliferation and potential bleeding secondary to the initial stimulation.19 If the agent is given during menses, by the end of the next cycle, the endometrium should be atrophic. If the agent is given midcycle to late in the cycle, the surgeon needs to wait until the completion of the following menstrual cycle.
In addition to thinning the endometrium, GnRH agonists also have other effects in preparation for a hysteroscopic myomectomy, such as causing myomas to shrink. Studies differ on the amount, but the decrease is in the range of 30% to 50% by the second to third month of treatment.20, 21 Most studies do not demonstrate significantly more shrinking after the third month, so using the medication for more than 3 months for this purpose alone has little benefit. Medically shrinking the myoma should allow for a quicker removal. With a shorter surgery, the patient has less exposure to the potential toxicities of the distension media. In large myomas, it may make the difference between completing the procedure in one step versus having to stage the removal secondary to fluid and electrolyte risks.
GnRH agonists also cause a contraction of the uterine vessels to approximately one-half their initial diameter, which results in decreased bleeding from exposed vessels during resection. Therefore, less infusion of the distention fluid is required to clean the blood. Perino et al22 demonstrated that by giving leuprolide acetate preoperatively to patients undergoing hysteroscopic myomectomy, there was a significant decrease in operative time, intraoperative bleeding, volume of distention fluid infused, and persistence of fibroids 2 months postoperatively.
In spite of the above, the use of GnRH analog pretreatment is controversial. Campo et al suggested that, even in very anemic patients, both short-term and long-term outcomes are unchanged. In addition, they found that those patients who had been pretreated with GnRH analogs had a significantly longer surgery. They attributed this increase in surgical time to the difficulty in dilating a stenotic cervical os in a patient who had been deprived of estrogen preoperatively.23
Patients should be warned about the potential side effects of GnRH agonists before use. Most patients experience symptoms similar to those felt in early menopause, including hot flushes and vaginal dryness. Many have severe mood swings and changes in weight. Rare problems such as bone pain may also occur, so surgeons should not use the medication longer than is thought necessary to best prepare the patient for surgery.
A few reports have been written on using suction curettage as a way to optimize the cavity before hysteroscopy.24, 25 The claimed advantage is decreased cost because time is saved, and it is easier to schedule the procedure, not just at the follicular stage. Less medication is used; therefore, there is less risk for ensuing complications, and tissue from the entire cavity is sent for evaluation, not just fibroid tissue. Cases of hyperplasia that are not readily visually apparent would therefore not be missed. However, many of these patients will have had an endometrial biopsy before going to the operating room, decreasing the chance of missing other pathology. By curetting the cavity in a premenopausal woman with the intention of removing the entire endometrium, the risk for intrauterine adhesions that could affect fertility is theoretically higher. In addition, by disrupting the entire cavity, there is significantly more intrauterine bleeding, increasing the amount of distention fluid to clear and the risk of fluid imbalance. Although it is helpful to have some data supporting this technique when one finds oneself in the operating room with an unprepared endometrium for whatever reason, it is not the ideal method of uterine preparation for hysteroscopic myomectomy.
Cervical preparation can aid in the procedure as well. A postmenopausal or nulliparous woman may have a cervix that is difficult to dilate. The use of preoperative laminaria or intravaginal dinoprostone may help soften the cervix and allow for dilatation appropriate for the resectoscope. Although it is rare for this to actually be necessary for cervical dilatation, the less difficult the surgeon finds each step of the procedure, the less likely he or she is to experience any complication.
Newer techniques are available for the resection of submucosal myomas, and they are discussed in a later section. Here, we focus on the use of the resectoscope with a loop electrode.
The procedure begins with the selection of equipment. As previously discussed, the resectoscope comes in different sizes on the French(F) scale, the most common of which are 24F to 28F, and the loop electrode comes with different angles. The telescopes also come with different angles from 0 to 30 degrees. Most surgeons are limited to whatever their operating room has available to them; however, if there is a choice, the surgeon should try different sizes to determine the one with which he or she is most comfortable.
With the current use of saline-infused ultrasound and MRI, in most cases, the surgeon can be fairly certain that he or she is dealing with a submucosal myoma. In these cases, it is best to go directly into the cavity with the resectoscope and not to use the diagnostic scope first. The main reason is that there is only so much fluid that the patient can absorb before the case must be stopped. It is useless to waste this time on an initial survey with the diagnostic hysteroscope. The extremely rare risk of cervical damage is far outweighed by the increased risk of fluid overload.
The next important step is cervical dilatation. It is important not to overdilate the cervix because this may lead to loss of distention fluid around the resectoscope and difficulty in distending the cavity to appropriately see the myoma. This may be a problem in the case of a prolapsing myoma, in which the cervix is already significantly dilated before starting the procedure. In a case in which the cervix has been overdilated, either by surgical error or by a prolapsing myoma, the surgeon can try to occlude the cervix by placing towel clamps either unilaterally or bilaterally on the cervix. Another option that is typically more successful in achieving the appropriate occlusion but takes more time involves placing a cerclage-like stitch around the cervix that can be tied around the resectoscope. The stitch can then be removed at the end of the procedure. It is also important not to underdilate the cervix because larger myomas often require forward-and-backward movements of the entire resectoscope. This movement may be limited if the cervix is not sufficiently dilated, leading to possible complications.
The typical procedure is performed with a 12-degree telescope and a 90-degree loop. The resectoscope is designed so that the electrode has a spring that brings it back to the sheath, which is insulated at the end to protect the patient from inadvertent bleeding. The electrode should be maximally extended to give the best visualization of the pathology during the resection. The movement of the electrode during the resection should always be toward the operator. Movement away from the operator is more likely to result in uterine perforation and potential serious injury to the patient. There likely will be times when the loop is not visible as it should be on the far side of the myoma to resect it toward the operator; however, energy should be used only as the electrode is moved toward the operator. For larger myomas, the entire resectoscope must occasionally be moved with the electrode to shave off the entire length.
While shaving the myoma, difficulties often occur with the pieces. Occasionally, they get trapped between the electrode and the lens. This can usually be corrected by separating the electrode from the lens and making sure the flow of the distention medium is working. A piece of the myoma may also become attached to the electrode. Surgeons often struggle in vain to remove these pieces. If the surgeon simply continues the procedure, the piece will typically come off with the next cut. Occasionally, the surgeon may find it difficult to cut through the myoma with the electrode. This is typically because the power is set to too low wattage or the surgeon is using a coagulation current instead of a cutting current. A cutting current wattage of 80W to 100W is typically adequate for smoothly slicing the myoma. The current works better by arcing it toward the tissue; therefore, it is best to start the current just before the electrode actually makes contact with the tissue and to continue the movement smoothly. Moving too slowly may result in a coagulation of the tissue and a sticking of the electrode. Moving too quickly may lodge the electrode into tissue that has not yet been cut. Using the coagulation current at a setting between 30W and 40W is appropriate for stopping bleeding from any significant vessels from the myoma. It is not useful for shaving the myoma because the peak voltage that is required makes this more dangerous to peripheral tissue both inside and outside the uterus. Also, the intermittent current makes the cells less likely to desiccate and therefore cut the tissue and more likely to char the tissue.
Bubbles may occur during cutting as a result either of gas forming during the cutting itself or of air in the inflow tubing. These can be visually distracting to the operator. It is important to make a good seal throughout the circuit of the distention fluid. When bubbles form in the cavity, placing the end of the resectoscope directly into the bubble and making sure that the outflow is turned on will usually eliminate the problem.
With regard to removing the myoma, debate exists as to how aggressive the surgeon should be. Many surgeons believe that for maximal safety, an operator should not resect below the endometrial surface. One would automatically believe that this may leave a significant part of the myoma behind. However, when the myoma is shaved from the cavity, surgeons will find that the normal contractile nature of the uterus tends to force the intramural portion of the myoma into the cavity. It is frequently possible to remove the entire myoma in this fashion without actually having to dissect below the endometrial surface. For this technique to be successful, it is necessary to have at least 40% to 50% of the myoma protruding into the cavity when starting the procedure.
Some surgeons insist that it is prudent to remove the entire myoma, regardless of the depth in which it is situated in the myometrium. Although it is true that the procedure is more likely to achieve long-term success when the entire myoma is removed, the risks of perforation and subsequent injury to bowel or vascular structures increase significantly as one dissects deeper into the myometrium. Ultrasound guidance occasionally has been used to determine depth and distance from the serosa, but it does not eliminate the potential risks. Indman26 proposed injecting carboprost, a methyl analogue of prostaglandin F2a, into the cervix. He reported on a series of 13 patients with a significant amount of submucosal intramural myoma. He found that the carboprost caused uterine contraction, allowing 11 of 13 myomas to be completely excised. No randomized study has been performed, and as this frequently happens without any injection, it is unclear whether carboprost truly makes any difference. As a general rule, a surgeon should proceed with extreme caution when dissecting below the endometrium.
Although it is a relatively safe procedure compared with abdominal myomectomy, hysteroscopic myomectomy has potential risks as well. The risks of fluid overload and hyponatremia are discussed earlier in this chapter. The risk of uterine perforation is higher in resectoscope cases. The cervix must be dilated to a greater amount to accommodate the large instrument, which may lead to perforation during dilatation. This is usually recognized once the scope is placed, either because the resectoscope goes directly into the abdominal cavity or because there is an immediate fluid imbalance. If the perforation occurs before the use of the electrodes, the procedure must be stopped; however, the patient usually may simply be monitored in the recovery room for signs of intraabdominal bleeding. Stable serial hemoglobin levels are reassuring, and the patient can be sent home and the procedure reattempted another day.
If the perforation occurs with the resectoscope while the electrode is charged, the potential for serious injury exists. The patient must have a thorough evaluation of the abdomen and pelvis, typically via laparoscopy, to determine the presence and extent of any injury. Unfortunately, thermal injury to the intestine is not always readily apparent. If the bowel has been burned but not incised, the defect may only become apparent after a few days. Patients discharged home after this type of complication should be advised to monitor their temperature and report any gastrointestinal symptoms, specifically nausea and vomiting.
Another possible complication after this procedure, especially in patients with a desire for future fertility, is intrauterine adhesions. These are more likely if two opposite fibroids have been resected so that the surfaces are juxtaposed after the procedure is completed. Although this is rare, if it occurs, the surgeon has the option of giving the patient supplemental estrogen immediately postoperatively, with the goal of rapidly developing the endometrium to prevent adhesions. Another method attempted in the past was the placement of an intrauterine Foley catheter to keep the opposite surfaces away from one another until estrogen formed spontaneously.
The immediate postoperative care of patients having undergone hysteroscopic myomectomy is generally not complicated. If an imbalance of fluid is noted during the procedure, the recovery room nurse should monitor the patient for signs and symptoms of fluid overload and hyponatremia, including bradycardia, hypertension, nausea, vomiting, seizures, pulmonary edema, and abnormalities. The management of these problems has been previously discussed in this chapter. There is typically not much pain after this procedure. At our institution, we found that Ketorolac 30mg given IV soluset at the completion of the procedure is usually adequate anesthesia; our patients are not sent home with narcotics but are told to use an anti-inflammatory medication such as ibuprofen. The need for more significant pain control can be an indication of more serious injury during the surgery and should be evaluated appropriately.
Patients should be told to expect per vaginal bleeding for approximately 1 week after the surgery. The duration of bleeding may vary from a few days to 2 weeks, but the flow is usually very light. Patients should also be warned that their cycle may be abnormal for the next month or two, and a heavy menses following the procedure is not indicative of what their usual menses will be like once they return to a regular cycle.
In some cases, a single procedure is not enough to entirely resect a myoma, and a repeat procedure is necessary. The chance of performing a complete resection depends more on the intramural extension of fibroids than on their size, number, or position.27 For patients with type I myomas, the entire lesion can usually be resected in a single procedure. However, for type II myomas, a two-stage procedure may be necessary. In those cases, a GnRH analogue is usually given between surgeries, and the second procedure is done approximately eight weeks after the first.28 A reoperation rate of 26% has been reported for type 0 and type I myomas, whereas a rate of 50% has been reported for type II myomas.29
LONG-TERM RESULTS: MENORRHAGIA AND FERTILITY
The only true cure for uterine myoma is a total hysterectomy. Even women undergoing a supracervical hysterectomy for myomas should be advised that there is a very small risk of developing a cervical myoma in the future. It is therefore inherent in the hysteroscopic myomectomy procedure that a success rate of 100% should not be expected. Some surgeons argue that the immediate, postoperative results should be close to 100% of the time. However, many women have anatomically normal uteruses with menorrhagia, dysfunctional uterine bleeding. It is impossible to know whether a woman with a submucosal myoma is bleeding irregularly solely because of the myoma or because of some other undetectable problem in her uterus. Only by removing the myoma would this be found; however, its presence would be considered a surgical failure, even though the goal of removing the myoma may have been completely successful. We know from data on abdominal myomectomies that up to 30% of women who undergo the procedure will require an intervention for myomas in the future. There is no reason to believe that this should not be the case for patients with submucosal myomas as well.
Studies now exist looking at one to nine years of follow-up of hysteroscopic myomectomies. Hysteroscopic myomectomy has at least an 80% success rate for up to nine years after surgery. Although it may seem that a failure rate of 20% is significantly high for any procedure, it is important to remember that the alternative would have been for the patients to have undergone a hysterectomy, with its associated increase in complications, pain, and lost productive time. In these studies, approximately half the patients who failed the procedure required a hysterectomy subsequently and the others had other forms of interventions usually another hysteroscopy. At least 90% of these patients were able to avoid a hysterectomy by undergoing a minimally invasive outpatient procedure that has considerably fewer risks. Investigators are still looking at the long-term results of hysteroscopic myomectomy. Study results vary, but generally success rates between 60-90% are reported. Polena et al30 reported on a study of 235 women, some of whom underwent both hysteroscopic myomectomy and others of whom underwent both hysteroscopic myomectomy and ablation with a mean follow up of 40 months. In cases of type II myomas, some patients required a second procedure for full resection. Overall, they reported a 94.4% success rate. Of their failures, four required repeat hysteroscopy, three required hysterectomy, and four complained of continued menorrhagia, but did not undergo further surgical treatment during the study follow-up time.
In a similar study, Emanuel et al31 did a retrospective review of 285 women who underwent hysteroscopic myomectomy without the additional procedure of an endometrial ablation. With a median follow up of 42 months, they showed that the number of procedures needed to complete resection of the myoma corresponded to the European Society of Gynecologic Endoscopy’s classification of the myoma, which is consistent with other data in the literature. In their study, they found that patients with a normal-sized uterus and two or less myomas had a 9.7% risk of requiring reoperation within five years of their initial surgery. Conversely, in women with an enlarged uterus and three or more myomas, there was a greater than 35% chance of reoperation within five years. This highlights the importance of both patient selection and patient counseling regarding outcomes, particularly in patients in the latter group who choose to undergo hysteroscopic myomectomy in spite of the higher risk of failure.
Infertility is another common reason for undergoing hysteroscopic myomectomy. The incidence of myomas in infertile women without any obvious cause of infertility is estimated to be between 1% and 2.4%.32 Again, infertility is multifactorial, and many patients who are infertile will not be found to have any apparent problem. It is very possible that a woman may have infertility from an unknown source and have a submucosal myoma as well, so fertility rates after resection of myoma should be evaluated with this information in mind. Pregnancy rates vary from 35% to 70%, representing a dramatic increase in fertility after hysteroscopic myomectomy in patients having infertility and a submucos myoma. Given that women with infertility due to a myoma typically would have had limited options, a hysteroscopic myomectomy, in spite of its associated morbidity, clearly indicates advancement over hysterectomy.
Many theories have been proposed regarding the reason for myomas to cause infertility. There is general agreement that fibroid location is of utmost importance, with submucous fibroids having the highest association with infertility, followed by intramural and finally subserosal fibroids. In addition, fibroids may cause dysfunctional uterine contractility, tubal ostia may be blocked, the cervix may be blocked, and transport of the sperm and ovum may be affected.32, 33 However, the problems with myomas do not end there. They are also associated with failed implantation and spontaneous abortion due to inflammation, atypical vasculature, etc.32, 34 If pregnancy does proceed to viability, patients with fibroids often often have preterm labor, premature rupture of the membranes, abdominal pain, malpresentation, and obstructed labor.
Stamatellos et al35 analyzed in the impact of the type of submucous myoma on fertility rates. It was a small study that only looked at twenty-five patients, but they found that hysterosopic myomectomy improved fertility rates by 57.1% for patients with type 0 myoma and 42.8% for type I myomas. They did not find that transcervical myomectomy improved fertility in patients with type II myomas. In those patients who achieved pregnancy, 35.7% of those with a type 0 myoma delivered at term, as compared to 28.5% with a type I myoma and 25% with a type II myoma after having undergone fibroid resection.
A metaanalysis showed that type 0 and type I myomas measuring three cm or less are effectively treated by resection, with improvement in dysfunctional uterine bleeding and improved fertility. Neither outcome is consistently improved in type II myomas. Again, fibroid type and location are the most important factors. In addition, a distorted uterine cavity has a negative effect on the success of IVF, and myomectomy should be completed prior to IVF cycles. Interestingly, age does not affect the fertility rate after hysteroscopic resection, nor does the presence of primary or secondary infertility.36
Every surgical procedure has complications, and hysteroscopic myomectomy is no exception. As complications relating to the distension media were previously addressed in the section on distention media, they will not be readdressed here. Some complications of hysteroscopy are directly related to the use of hysteroscopy, such as complications from the distention media, while other relate to surgical technique, such as uterine perforation. Complication rates vary, but most complication rates quoted in the literature range from 0.86-2.7%.37, 38
Uterine perforation can happen at any stage during the procedure and is estimated to occur in 0.4% to 1.6% of operative hysteroscopies.39 It is the most common complication of hysteroscopic surgery.40 If a surgeon suspects that uterine perforation has occurred, laparoscopy should be performed to assess for intraperioneal bleeding and damage to other intraperitoneal structures such as the bowel. Avoid placing an intrauterine balloon for two reasons. First, it may extend the tear, creating more damage to the tissue. Second, it may conceal bleeding behind the balloon resulting in life-threatening blood loss that is unrecognized by the surgeon. Although small tears measuring less than 5 mm can usually be left to heal themselves unless they are actively bleeding,41 the authors would recommend a hysterosalpingogram to ensure the integrity of the uterine wall after a perforation prior to pregnancy.
In some cases of uterine perforation, there will also be damage to the bowel, although it is quite rare. Studies have not shown any change in outcome with primary closure of the bowel injury vs. colostomy. It is recommended to institute short-duration single-agent broad spectrum antibiotics to cover Bacteriodes and coliform bacteria. The use of a drain has not been shown to improve outcomes. Overall, young healthy patients with bowel injury from hysteroscopy tend to do very well.40
The most common cause of hemorrhage in the setting of hysteroscopy is uterine perforation, which was discussed above. In a review of 2116 patients undergoing operative hysteroscopy, heavy bleeding was reported in thirteen cases, or 0.61%.42 Hemorrhage can be controlled with uterine artery ligation. This can be performed vaginally if the surgeon has adequate skill. A Bakri intrauterine balloon can also be placed for tamponade, but this is not recommended if the patient has a perforation. Once the balloon is placed, it is left for twenty-four to forty-eight hours and then slowly decompressed. In cases of severe, life-threatening hemorrhage, hysterectomy may be performed. As with any surgical hemorrhage, it is important to communicate with the anesthesiologist about ongoing blood loss and transfuse blood products as necessary.
Bleeding occurring from the tenaculum site on the cervix can usually be controlled with pressure applied with a sponge holder. Hemostatic agents such as silver nitrate sticks and Monsel’s solution can also be used. To decrease bleeding from the tenaculum site, the authors recommend the use of a double-toothed tenaculum or a long Allis clamp rather than a single-toothed tenaculum. Tears often require suturing.
Infection after transcervical myomectomy remains low, and it is not currently recommended to give prophylactic antibiotics. In a recent study of 631 women undergoing hysteroscopy who were either given antiobiotic prophylaxis or prophylaxis with amoxicillin-clavulanate acid and doxycycline, only one patient was infected after the procedure, and that patient had received antibiotics prior to the surgery.43 Rare infectious complications including toxic shock syndrome,44 broad ligament abscess,45 and pyometra46 have also been reported.
Uterine synechiae are emerging as an important complication in operative hysteroscopy, especially when it is performed for the purpose of fertility. A recent study from France looked at fifty-three patients who underwent hysteroscopic myomectomy for infertility attributed to submucous myomas. Two months postoperatively, patients underwent a diagnostic hysteroscopy to assess for synechiae. They reported a synechiae rate of 7.5%, which was lower than previous studies. They attributed their low rate of synechiae to the use of bipolar rather than monopolar cautery.47
New techniques for the treatment of uterine myomas are continually developing, and, although some seem promising, long-term data are lacking to assess their relative merits. With proper case selection and training, hysteroscopic myomectomy remains the treatment of choice for most submucous myomas. Surgeons are always trying to improve on current techniques in an attempt to decrease operative risks and improve outcomes. The development of the hysterectomy myomectomy is an example of this, and, within the context of hysteroscopic myomectomy, advances continue. Because of the fluid balance risks, better fluid management systems have emerged over the last few years that greatly enhance the surgeon’s ability to closely monitor the fluid balance to significantly decrease the risk of the patient ever developing hyponatremia or general fluid overload. The most advanced system would monitor input and output, maintain a hysteroscopic intrauterine pressure sufficient to distend the cavity but not excessively, present all these data on the video screen used for the procedure, and have alarms to alert the surgeon when any parameters reach levels of increased risk. Surgeons would have to consciously choose to ignore the warnings to cause harm. As with any device, there is always the risk of instrument error, so the surgeons should not have a complete sense of security with this instrumentation. Having the equipment decreases the risks but does not excuse the surgeon from monitoring all aspects of the surgery closely so as to catch equipment errors if they arise. Although there is no correction for poor surgical technique or judgment on the part of the surgeon, new devices limit the risk as much as possible.
Because a monopolar electric current is somewhat uncontrolled once it leaves the electrode, many surgeons believe a bipolar device is safer. With the standard monopolar electrode, the current has its greatest effect within millimeters from the electrode. It is then dispersed in all directions and is reaccumulated at the grounding pad and returned to the generator. The dispersed current is usually too weak to cause harm. The current will flow in the path of least resistance. In the setting of a hysteroscopic myomectomy, the myoma and the tissue surrounding it generally have a uniform resistance, so the current flows in all directions. If there is aberrant anatomy, it is possible that a channel of less resistance might exist, concentrating the current and potentially harming the patient. This is the reason the grounding pads are wide: if they were attached at a single point, the entire current would accumulate at that point and cause injury.
Bipolar instruments have opposing electrodes that are positive and negative, so the current flows only between the electrodes and is not dispersed throughout the patient. This more-controlled current should be safer, because it is not dispersed through the patient. The Versa Point system by Gynecare is an example of a system with this design. Clark et al48 performed a feasibility study on this technique, which they reported in 2002. Using the bipolar device, they operated on 37 women with submucosal myomas. They found that 92% of patients were satisfied with the procedure, although only 72% reported improvement in bleeding. There were no operative complications, and the author considered this technique to be an improvement over the standard monopolar technique.
In addition to the increased safety of the better-controlled current, bipolar techniques offer another advantage. Using a bipolar electrode allows the surgeon to use normal saline as the distending fluid. Although this does not eliminate the risks of fluid overload, it greatly decreases the risk of hyponatremia. This does not eliminate the need for close fluid monitoring, because at least one death has occurred as a result of fluid overload with this system. However, it increases the amount of fluid that may be safely absorbed to 2000mL to 2500mL, which may give the surgery valuable additional time to perform the procedure completely.
The bipolar technique also has improved with regard to the tissue affected by the current. In most cases, as the electrode is moved through the myoma, it completely vaporizes the tissue. This eliminates or greatly decreases the number of floating pieces of myoma that obscure the operative field, which may both lengthen the procedure and increase operative errors due to the obstructed view. One negative would be that the tissue is not evaluated by a pathologist to assure that the treated lesion is indeed a simple myoma and not a more serious condition, such as a sarcoma. This is very rare, however, and may not outweigh the benefits offered by this technique.
Another new technique eliminates the risk of electrosurgery. The Smith & Nephew operative hysteroscopy system involves a rotating morcellating blade. The opening is on the side of the distal end of the hysteroscope. This opening is placed on the myoma, and the rotating blade shaves the myoma. The cutting is all sharp, because no electric current is used. The shaved pieces are immediately suctioned out of the uterus through the scope and collected for pathologic review. This technique used the normal contraction of the uterus that occurs during a hysteroscopic myomectomy to both force the myoma out of the myometrium and contract the vessels surrounding the myoma to decrease bleeding. This technique limits the surgeon’s ability to dissect deeper into the uterine wall to remove the entire myoma if it is not expelled by uterine contractions, a limitation that is probably safer for the patient. The procedure, like the bipolar technique, may be performed with normal saline, with the same decreased risk of hyponatremia. Surgeons should have some type of electrosurgery device available to manage bleeding should it occur.
The opportunity to improve patient care drives those in the medical field to constantly search for new devices and techniques. With the adoption of the resectoscope, gynecologists have been able to save countless women from experiencing excessive pain, lost productive time, and unnecessary major surgery. Although risk exists in everything we do as surgeons, the resectoscope greatly reduces those involved in surgeries for uterine myomas. Advances continue to reduce these risks and make the options for treatment of uterine myoma safer for women suffering from the effects of this condition.
As this chapter explains, the benefits of hysteroscopic myomectomy are substantial, and it is not surprising that this technique is becoming increasingly propular, both among gynecologic surgeons and patients. In addition, hysteroscopic myomectomy is 40% less costly than other surgical treatments of fibroids48 with quick recovery times. Proper patient selection is vital for the desired outcome. In addition, the gynecologic surgeon needs to have a thorough understanding of the equipment used, the electrosurgical principles, and distension media with the attendant risks. Prior to taking a patient to the operating room for this procedure, the physician must know the location and depth of the myoma. Standard precautions should be taken to avoid complications. Gynecologists should stay abreast of the latest technologic developments and incorporate them when appropriate. Most importantly, physicians need to realize that this can be a difficult procedure, and it should not be undertaken in inexperienced hands.
1. Neuwirth RS, Amin HK. Excision of submucus fibroids with hysteroscopic control. Am J Obstet Gynecol 1976;126:95-9.
2. Nesbit R, ed. A history of transurethral prostatic resction. New York: Appleton-Century-Crofts and Fleschner Publishing Company; 1977.
3. M. S. Resection of obstruction at the vesical orifice. JAMA 1926;87:1726-30.
4. A dA. Action physiologique des courants alternatif a grand frequence. Arch Physiol Norm Pathol 1892;5:401-8.
5. Goldwyn RM. Bovie: the man and the machine. Ann Plast Surg 1979;2:135-53.
6. McCarthy J. The management of prostatic obstruction by endoscopic revision. N Engl J Med 1932;207:305-12.
7. Iglesias JJ, Sporer A, Gellman AC, Seebode JJ. New Iglesias resectoscope with continuous irrigation, simultaneous suction and low intravesical pressure. J Urol 1975;114:929-33.
8. Nezhat C, Crowgey SR, Garrison CP. Surgical treatment of endometriosis via laser laparoscopy. Fertil Steril 1986;45:778-83.
9. Di Spiezio Sardo A, Mazzon I, Bramante S, et al. Hysteroscopic myomectomy: a comprehensive review of surgical techniques. Hum Reprod Update 2008;14:101-19.
10. Baggish M, Brill AI, Rosenweig B, Barbot JE, Indman P. Fatal acute glycine and sorbitol toxicity during operative hysteroscopy. J Gynecol Surg 1993;9:137-43.
11. Tapper AM, Heinonen PK. Experience with isotonic 2.2% glycine as distension medium for hysteroscopic endomyometrial resection. Gynecol Obstet Invest 1999;47:263-7.
12. de Vries LD, Dijkhuizen FP, Mol BW, Brolmann HA, Moret E, Heintz AP. Comparison of transvaginal sonography, saline infusion sonography, and hysteroscopy in premenopausal women with abnormal uterine bleeding. J Clin Ultrasound 2000;28:217-23.
13. Jo YY, Jeon HJ, Choi E, Choi YS. Extreme hyponatremia with moderate metabolic acidosis during hysteroscopic myomectomy -A case report. Korean J Anesthesiol 2011;60:440-3.
14. Lewis BV M, AL, ed. Fibroids. Edinburgh: Churchill Livingstone; 1993.
15. Cepni I, Ocal P, Erkan S, et al. Comparison of transvaginal sonography, saline infusion sonography and hysteroscopy in the evaluation of uterine cavity pathologies. Aust N Z J Obstet Gynaecol 2005;45:30-5.
16. Salim R, Lee C, Davies A, Jolaoso B, Ofuasia E, Jurkovic D. A comparative study of three-dimensional saline infusion sonohysterography and diagnostic hysteroscopy for the classification of submucous fibroids. Hum Reprod 2005;20:253-7.
17. Lefebvre G, Vilos G, Allaire C, et al. The management of uterine leiomyomas. J Obstet Gynaecol Can 2003;25:396-418; quiz 9-22.
18. Nilsson L, Rybo G. Treatment of menorrhagia. Am J Obstet Gynecol 1971;110:713-20.
19. Brooks PG, Serden SP. Preparation of the endometrium for ablation with a single dose of leuprolide acetate depot. J Reprod Med 1991;36:477-8.
20. Friedman AJ, Hoffman DI, Comite F, Browneller RW, Miller JD. Treatment of leiomyomata uteri with leuprolide acetate depot: a double-blind, placebo-controlled, multicenter study. The Leuprolide Study Group. Obstet Gynecol 1991;77:720-5.
21. Coddington CC, Brzyski R, Hansen KA, Corley DR, McIntyre-Seltman K, Jones HW, Jr. Short term treatment with leuprolide acetate is a successful adjunct to surgical therapy of leiomyomas of the uterus. Surg Gynecol Obstet 1992;175:57-63.
22. Perino A, Chianchiano N, Petronio M, Cittadini E. Role of leuprolide acetate depot in hysteroscopic surgery: a controlled study. Fertil Steril 1993;59:507-10.
23. Campo S, Campo V, Gambadauro P. Short-term and long-term results of resectoscopic myomectomy with and without pretreatment with GnRH analogs in premenopausal women. Acta Obstet Gynecol Scand 2005;84:756-60.
24. Gimpelson RJ, Kaigh J. Mechanical preparation of the endometrium prior to endometrial ablation. J Reprod Med 1992;37:691-4.
25. Lefler HT, Jr., Sullivan GH, Hulka JF. Modified endometrial ablation: electrocoagulation with vasopressin and suction curettage preparation. Obstet Gynecol 1991;77:949-53.
26. Indman PD. Use of carboprost to facilitate hysteroscopic resection of submucous myomas. J Am Assoc Gynecol Laparosc 2004;11:68-72.
27. Vercellini P, Zaina B, Yaylayan L, Pisacreta A, De Giorgi O, Crosignani PG. Hysteroscopic myomectomy: long-term effects on menstrual pattern and fertility. Obstet Gynecol 1999;94:341-7.
28. Wamsteker K, Emanuel MH, de Kruif JH. Transcervical hysteroscopic resection of submucous fibroids for abnormal uterine bleeding: results regarding the degree of intramural extension. Obstet Gynecol 1993;82:736-40.
29. Lumsden MA, Wallace EM. Clinical presentation of uterine fibroids. Baillieres Clin Obstet Gynaecol 1998;12:177-95.
30. Polena V, Mergui JL, Perrot N, Poncelet C, Barranger E, Uzan S. Long-term results of hysteroscopic myomectomy in 235 patients. Eur J Obstet Gynecol Reprod Biol 2007;130:232-7.
31. Emanuel MH, Wamsteker K, Hart AA, Metz G, Lammes FB. Long-term results of hysteroscopic myomectomy for abnormal uterine bleeding. Obstet Gynecol 1999;93:743-8.
32. Hunt JE, Wallach EE. Uterine factors in infertility--an overview. Clin Obstet Gynecol 1974;17:44-64.
33. Vollenhoven BJ, Lawrence AS, Healy DL. Uterine fibroids: a clinical review. Br J Obstet Gynaecol 1990;97:285-98.
34. Deligdish L, Loewenthal M. Endometrial changes associated with myomata of the uterus. J Clin Pathol 1970;23:676-80.
35. Stamatellos I AA, Stamatopoulos P, Bontis J. Fertility rates after hysteroscopic treatment of submucous myomas depending on their type. Gynecol Surg 2006;3:206-10.
36. Rackow BW, Arici A. Fibroids and in-vitro fertilization: which comes first? Curr Opin Obstet Gynecol 2005;17:225-31.
37. Propst AM, Liberman RF, Harlow BL, Ginsburg ES. Complications of hysteroscopic surgery: predicting patients at risk. Obstet Gynecol 2000;96:517-20.
38. Ozturk E, Ugur MG, Balat O, Kutlar I, Dikensoy E, Cebesoy B. An analysis of hysteroscopy experience over a seven-year period. Clin Exp Obstet Gynecol 2010;37:150-1.
39. Ubaldi F, Tournaye H, Camus M, Van der Pas H, Gepts E, Devroey P. Fertility after hysteroscopic myomectomy. Hum Reprod Update 1995;1:81-90.
40. Sullivan B, Kenney P, Seibel M. Hysteroscopic resection of fibroid with thermal injury to sigmoid. Obstet Gynecol 1992;80:546-7.
41. Corson SL. Hysteroscopic diagnosis and operative therapy of submucous myoma. Obstet Gynecol Clin North Am 1995;22:739-55.
42. Agostini A, Cravello L, Desbriere R, Maisonneuve AS, Roger V, Blanc B. Hemorrhage risk during operative hysteroscopy. Acta Obstet Gynecol Scand 2002;81:878-81.
43. Kasius JC, Broekmans FJ, Fauser BC, Devroey P, Fatemi HM. Antibiotic prophylaxis for hysteroscopy evaluation of the uterine cavity. Fertil Steril 2011;95:792-4.
44. Parkin DE. Fatal toxic shock syndrome following endometrial resection. Br J Obstet Gynaecol 1995;102:163-4.
45. Rullo S, Boni T. Broad ligament abscess after operative hysteroscopy. Clin Exp Obstet Gynecol 1995;22:240-2.
46. Amin-Hanjani S, Good JM. Pyometra after endometrial resection and ablation. Obstet Gynecol 1995;85:893-4.
47. Touboul C, Fernandez H, Deffieux X, Berry R, Frydman R, Gervaise A. Uterine synechiae after bipolar hysteroscopic resection of submucosal myomas in patients with infertility. Fertil Steril 2009;92:1690-3.
48. Clark TJ, Mahajan D, Sunder P, Gupta JK. Hysteroscopic treatment of symptomatic submucous fibroids using a bipolar intrauterine system: a feasibility study. Eur J Obstet Gynecol Reprod Biol 2002;100:237-42.