INTRODUCTION — Endometrial ablation is a minimally invasive option for the treatment of abnormal uterine bleeding. Resectoscopic techniques are performed under hysteroscopic visualization, using resectoscopic instruments to ablate or resect the endometrium. These techniques are also referred to as standard or first-generation ablation. Non-resectoscopic endometrial ablation, also referred to as second-generation ablation, is performed with a device that is inserted into the uterine cavity and delivers energy to uniformly destroy the uterine lining.

Resectoscopic techniques for endometrial ablation will be reviewed here. General principles (eg, indications, contraindications, preoperative and postoperative care) of endometrial ablation, techniques for non-resectoscopic endometrial ablation, as well as other management options for abnormal uterine bleeding, are discussed separately. (See "Overview of endometrial ablation" and "Endometrial ablation: Non-resectoscopic techniques" and "Abnormal uterine bleeding: Management in premenopausal patients".)

RESECTOSCOPIC ABLATION

Techniques — Resectoscopic ablation is done under hysteroscopic visualization and requires the use of a resectoscope (picture 1). There are currently four techniques [1]: (1) endometrial desiccation with an electrosurgical rollerball or rollerbarrel (picture 2) [2], (2) resection with a monopolar or bipolar loop electrode (picture 2) [3], (3) radiofrequency vaporization, or (4) laser vaporization [4].

All methods desiccate the endometrium to the level of the basalis. The rollerball and rollerbarrel use thermal energy for heating the tissue to a temperature between 60 to 90°C, which desiccates and destroys the tissue. No tissue is removed. Thermal energy is also used with the monopolar and bipolar loop electrodes. However, the loop electrodes also resect the endometrium beyond the basalis layer to the myometrium. The resected tissue is sent to pathology for histologic diagnosis.

The vaporizing electrodes and laser fibers use high energy to rapidly heat the intracellular water to 100°C, causing vaporization of tissue. No tissue is removed.

Rollerball endometrial ablation is the most commonly used resectoscopic ablation method. Wire loop endomyometrial resection requires advanced hysteroscopic skills because of the risk of perforation, bleeding, and fluid absorption. Laser and vaporizing electrode ablation are not commonly performed due to the high cost of this equipment.

Our approach to method selection — In current practice, non-resectoscopic endometrial ablation is performed in most cases because of ease of use and short operative time compared with resectoscopic techniques. However, the author performs resectoscopic ablation if the shape or size of the uterine cavity will not accommodate a non-resectoscopic device or if the patient has had multiple cesarean deliveries to avoid ablating over the hysterotomy scar. The author primarily uses the rollerball technique because, in his hands, it is quicker than resection, and increasing operative time equates with increased risk of fluid overload. The author does not use laser because the cost structure at his institution favors rollerball.

ROLLERBALL OR ROLLERBARREL OPERATIVE TECHNIQUE — General perioperative practices (eg, endometrial preparation, prophylactic antibiotics) and complications of endometrial ablation, as well as comparison with non-resectoscopic endometrial ablation, are discussed separately. (See "Overview of endometrial ablation", section on 'Complications' and "Overview of endometrial ablation", section on 'Non-resectoscopic versus resectoscopic ablation'.)

Instrumentation — Rollerball (or rollerbarrel) endometrial ablation is usually performed using monopolar electrical energy. Typically, the radiofrequency generator is set to 50 to 80 watts of coagulation or cutting current in order to desiccate the endometrium. We prefer cutting current, since coagulation current may result in vaginal burns caused by arcing and capacitance coupling [5].

Alternatively, a bipolar resectoscope can be used. The advantage of a bipolar system is that saline is used, rather than electrolyte-free hypoconductive fluid. Excessive absorption of hypoconductive fluids (eg, glycine) may result in hyponatremia. (See "Hyponatremia following transurethral resection, hysteroscopy, or other procedures involving electrolyte-free irrigation".)

Procedure — Positioning, sterile preparation, and cervical dilation are the same as for hysteroscopy. (See "Overview of hysteroscopy", section on 'Procedure'.)

●Insert the resectoscope through the cervix, distend the uterus with fluid, and inspect the uterine cavity.

●Position the rollerball at one of the uterine cornu. It is helpful to start the desiccation at the cornua and then move to the anterior fundal wall due to bubble formation in the uterine cavity. Complete the ablation on the posterior wall since the bubbles formed will be anterior. Activate the current and bring the rollerball towards the surgeon. To avoid injury, it is important to keep the rollerball in view at all times and activate it only when moving it towards the operator. Desiccating the endometrium to a depth of 5 to 6 mm ensures the endometrium is destroyed to the level of the basalis (figure 1) and is unlikely to regenerate in the presence of reproductive hormones. A thin endometrium will be quickly desiccated to this level. When the myometrium is reached, the surgeon will note small bubbles forming around the leading edge of the rollerball. Avoid desiccation of the cervico-uterine junction since this may result in cervical stenosis or uterine occlusion.

●Repeat this motion until the entire surface of the endometrium has been desiccated.

RESECTOSCOPIC OPERATIVE TECHNIQUE — General perioperative practices (eg, endometrial preparation, prophylactic antibiotics) and complications of endometrial ablation, as well as comparison with non-resectoscopic endometrial ablation, are discussed separately. (See "Overview of endometrial ablation", section on 'Complications' and "Overview of endometrial ablation", section on 'Non-resectoscopic versus resectoscopic ablation'.)

Instrumentation — Resectoscopic endometrial ablation is performed using monopolar electrical energy. Typically, the radiofrequency generator is set to 80 to 100 watts of cutting current or blend 1. In our practice, we prefer cutting current on 80 watts.

Cutting loops are available in different sizes, ranging from 4 to 8 mm. We use a 6 mm diameter cutting loop which, when inserted to its full radius, will resect 3 mm of tissue, though some surgeons prefer an 8 mm loop which removes 4 mm of tissue. Though the 4 mm loop may decrease the risk of damage, it requires longer resection times. We prefer the 6 mm loop as a good balance of speed and safety.

Procedure — Positioning, sterile preparation, and cervical dilation are the same as for hysteroscopy.

●Insert the resectoscope through the cervix, distend the uterus with fluid, and inspect the uterine cavity.

●Position the resection loop at the uterine fundus. It is helpful to start at the midline of the fundus, and we avoid resection at the cornua. We prefer to ablate the cornua with a rollerball to decrease the risk of perforation at this vulnerable region of the uterus. Complete the resection on the posterior wall since the bubbles formed will be anterior. Activate the current and bring the loop toward the surgeon. To avoid injury, it is important to keep the loop in view at all times and activate it only when moving it toward the operator.

●Repeat this motion until the entire surface of the endometrium has been resected, with the exception of the region of the cornua.

Nd-YAG LASER OPERATIVE TECHNIQUE — General perioperative practices (eg, endometrial preparation, prophylactic antibiotics) and complications of endometrial ablation, as well as comparison with non-resectoscopic endometrial ablation, are discussed separately. (See "Overview of endometrial ablation", section on 'Complications' and "Overview of endometrial ablation", section on 'Non-resectoscopic versus resectoscopic ablation'.)

Instrumentation — Neodymium:yttrium-aluminum-garnet (Nd-YAG) laser endometrial ablation is performed using an Nd-YAG laser in flexible quartz fibers directed to the endometrium. Quartz fibers come in variable diameters from 600 to 1200 micrometers. The 600 micrometer fiber is used most commonly at 50 to 75 watts. The Nd-YAG laser penetrates to a depth of 4 to 6 mm.

Procedure — Positioning, sterile preparation, and cervical dilation are the same as for hysteroscopy. (See "Overview of hysteroscopy", section on 'Procedure'.)

●Insert the resectoscope through the cervix, distend the uterus with fluid, and inspect the uterine cavity.

●Position the Nd-YAG laser at the uterine fundus. A bare fiber is used with approximately 5 to 10 mm of the end protruding through the distal end of the hysteroscope. This tip should be visualized at all times during activation. Parallel furrows are produced in the endometrium by dragging the fiber along the surface of the endometrium; this way, it is easier to differentiate treated versus nontreated areas.

●Repeat this motion until the entire surface of the endometrium has been ablated.

Patients with leiomyomas or polyps — Resectoscopic endometrial ablation can be performed in patients with submucosal leiomyomas. Patients who have a submucosal leiomyoma in the uterine cavity can have a hysteroscopic myomectomy followed by endometrial ablation. This concurrent procedure is limited by the amount of irrigation fluid absorbed (see "Hyponatremia following transurethral resection, hysteroscopy, or other procedures involving electrolyte-free irrigation"). It is uncertain whether this procedure is more effective at improving uterine bleeding symptoms than myomectomy alone. This topic is discussed in detail separately. (See "Uterine fibroids (leiomyomas): Hysteroscopic myomectomy", section on 'Concomitant procedures'.)

Endometrial polyps can be easily removed prior to ablation. (See "Endometrial polyps".)

OUTCOME — For patients undergoing resectoscopic endometrial ablation, we suggest rollerball endometrial ablation rather than wire loop endomyometrial resection, unless it is advantageous to send tissue for histology. Outcomes appear similar for these two techniques, but wire loop resection requires more surgical skill. Laser and vaporizing electrode ablation are not commonly performed due to expense of the equipment. The outcomes for resectoscopic endometrial ablation are discussed here. Complication rates of endometrial ablation and comparison of resectoscopic with non-resectoscopic ablation are discussed separately. (See "Overview of endometrial ablation", section on 'Complications' and "Overview of endometrial ablation", section on 'Non-resectoscopic versus resectoscopic ablation'.)

Effectiveness — Most patients with successful endometrial ablation will have a reduction in uterine blood flow but not amenorrhea. Studies vary according to whether menstrual blood loss is measured and the method used (eg, alkaline hematin method, pictorial blood assessment chart). Thus, amenorrhea, patient satisfaction, and subsequent surgery are more commonly used to assess treatment success than volume of uterine bleeding.

The best available data regarding resectoscopic ablation were presented in a 2019 meta-analysis of 28 trials (table 1) [6]. Major findings included:

●The overall comparison of resectoscopic and non-resectoscopic techniques found similar amenorrhea rates at either one year or two to five years of follow-up (one year: risk ratio [RR] 0.99, 95% CI 0.78-1.27, 12 trials, 2145 patients; two to five years: RR 1.16, 95% CI 0.78-1.72, 4 trials, 672 patients).

●The patient satisfaction rates at one year and two to five years of follow-up were similar between resectoscopic and non-resectoscopic techniques (one year: RR 1.01, 95% CI 0.98-1.04, 11 trials, 1750 patients; two to five years: RR 1.02, 95% CI 0.93-1.13, 4 trials, 672 patients).

●Assessment of subsequent surgery found little difference between the resectoscopic techniques for the rates of repeat ablation or hysterectomy at one year of follow-up or the rates of hysterectomy at five years of follow-up (one year: RR 0.72, 95% CI 0.41-1.26, 6 trials, 935 patients; five year: RR 0.85, 95% CI 0.59-1.22, 4 trials, 758 patients).

●Compared with resectoscopic techniques, non-resectoscopic techniques were associated with shorter operative times (mean difference -13.52 minutes, 95% CI -16.90 to -10.13, 9 trials, 1822 patients) and were more likely to be performed using local rather than general anesthesia (RR 2.8, 95% CI 1.8-4.4, 6 trials, 1434 patients).

One limitation of this meta-analysis was that most of the evidence was graded as being of low to moderate quality. The level of quality was down-graded because of inadequate concealment and lack of blinding in many trials.

Comparison among resectoscopic techniques — In the above meta-analysis, amenorrhea rates at one and two to five years of follow-up were similar for first- and second-generation techniques (one year: RR 0.99, 95% CI 0.78-1.27, 12 trials, 2145 patients; two to five years: RR 1.16, 95% CI 0.78-1.72, 4 trials, 672 patients) [6]. Comparison of rollerball, vaporizing electrode, and laser methods (first generation) with endomyometrial resection showed no significant differences in rates of reduced menstrual bleeding, amenorrhea, satisfaction rates at six months or one year of follow-up, or subsequent hysterectomy. Similarly, there was no significant difference in complications between ablation and resection; one study found a significant increase in irrigation fluid deficit (an additional 258 mL) with endomyometrial resection compared with vaporizing electrode. Some, but not all, trials found that resection had a longer operative duration than other types of resectoscopic ablation. The study with the longest follow-up was a randomized trial (not included in the meta-analysis) of 120 patients assigned to either rollerball ablation or wire loop resection [7]. At 10-year follow-up, 93 percent of patients in the study were amenorrheic. Patients treated with other types of resectoscopic ablation compared with resection had the following rates of subsequent surgery: repeat ablation (13 versus 8 percent) and hysterectomy (25 versus 19 percent); tests of significance were not reported.

General complications of resectoscopic and non-resectoscopic endometrial ablation are discussed separately. (See "Overview of endometrial ablation", section on 'Complications'.)

POSTOPERATIVE CARE — Postoperative care and other follow-up issues for endometrial ablation is discussed separately. (See "Overview of endometrial ablation", section on 'Follow-up'.)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Ectopic pregnancy".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topic (see "Patient education: Endometrial ablation (The Basics)")

SUMMARY AND RECOMMENDATIONS

●Resectoscopic endometrial ablation is a treatment for abnormal uterine bleeding that is performed under hysteroscopic visualization, using resectoscopic instruments to ablate or resect the endometrium. (See 'Introduction' above.)

●Resectoscopic ablation currently uses one of four techniques: endometrial desiccation with an electrosurgical rollerball or vaporizing electrode, laser endometrial desiccation, and endomyometrial resection using a wire loop. Rollerball endometrial ablation is the most commonly used resectoscopic method. (See 'Resectoscopic ablation' above.)

●Rollerball endometrial ablation can be performed with either a monopolar or bipolar resectoscope. (See 'Instrumentation' above.)

●Resectoscopic endometrial ablation can be performed in patients with small submucosal leiomyomas. Many surgeons remove the myoma prior to performing the ablation. Endometrial polyps can be easily removed prior to ablation. (See "Endometrial polyps" and 'Patients with leiomyomas or polyps' above.)

●All four methods of resectoscopic endometrial ablation have similar efficacy. Endometrial resection compared with non-resection methods requires more surgical skill, has a longer operative duration, and may result in an increased absorption of irrigation fluid. (See 'Effectiveness' above.)

●For patients undergoing resectoscopic endometrial ablation, we suggest rollerball endometrial ablation rather than wire loop endomyometrial resection (Grade 2C). Resection is preferred in patients in whom tissue is needed for histologic evaluation. Laser and vaporizing electrode ablation are not commonly performed. (See 'Outcome' above.)