INTRODUCTION

Hysteroscopy is an accurate surgical approach for evaluating the uterine cavity and treating a multitude of abnormalities. At its essence, it involves the transcervical placement of a lens and light system into the uterine cavity while using gas or liquid for distension of the cavity. Modern hysteroscopy is performed almost exclusively with the addition of a camera and video monitoring system. Operative hysteroscopy is performed using an electrosurgical resectoscope or a sleeve with an operating channel to accommodate instruments for grasping, biopsying, or cutting with scissors or laser.

Today, in addition to being an excellent diagnostic technique, hysteroscopy has proven to be an effective and minimally invasive treatment for abnormal uterine bleeding, infertility, and early pregnancy loss. Some of the most common uterine pathologic conditions treated by hysteroscopy are polyps and myomas. Even in patients without intrauterine pathology, endometrial ablation, first performed hysteroscopically, has decreased the need for hysterectomy in patients with abnormal uterine bleeding unresponsive to medical therapy.

This chapter describes the standard methods for diagnostic and operative hysteroscopy and then offers details of the hysteroscopic treatment of polyps and fibroids, both submucous and pedunculated intracavitary lesions. The chapter also describes techniques for endometrial ablation, including traditional hysteroscopic ablation and several innovative methods.

HISTORY

Hysteroscopy, first described in the late 1800s, did not find widespread clinical use for more than 100 years. In 1869, Pantaleoni performed the first diagnostic and therapeutic hysteroscopy when he used a modified cystoscope to look into the uterine cavity and cauterize a hemorrhagic growth.¹ Early hysteroscopists used a tube to mechanically distend the uterus for visualization. Near the beginning of the 20th century, Dr. Isidor C. Rubin, a New York gynecologist best remembered for Rubin’s test, first used carbon dioxide (CO₂) to distend the uterus for hysteroscopy. Around the same time, Professor C. J. Gauss, a German surgeon and descendant of the famous mathematician, first performed hysteroscopy using fluid distension media.² However, hysteroscopy did not find widespread acceptance for another half-century.³

In the 1970s interest in hysteroscopy renewed, in parallel with the rapid advancement of diagnostic and operative laparoscopy. Probably the most important advances came in the form of improved methods for distending the uterine cavity, including use of viscous and low-density liquid solutions. Around the same time insufflation machines were designed for CO₂ and fluid media that utilized high pressure and low flow, rather than the low pressure and high flow used for laparoscopy.^4–6 Carbon dioxide was often used for diagnostic hysteroscopy, and fluid media became the standard for operative hysteroscopy. It was found that isotonic fluid was ideal for most operative procedures, whereas nonconductive hypotonic media was required for electrosurgical procedures.

The use of hysteroscopy became widespread in the 1980s with the development of better optics and lighting and the use of video cameras. Operative techniques for various intrauterine pathologic conditions continued to be developed. Most notably among these may be removal of submucous myomas using an enhanced urologic resectoscope,⁷ removal of uterine septum,⁸ and endometrial ablation using laser,⁹ resectoscopic loop,¹⁰ or rollerball.¹¹ Today, hysteroscopy has become a standard diagnostic and therapeutic technique performed by most gynecologists.

INDICATIONS

BASIC HYSTEROSCOPIC EQUIPMENT AND TECHNIQUES

DIAGNOSTIC HYSTEROSCOPY

For the majority of the 20th century, the only method available for directly visualizing intrauterine pathology short of hysterectomy was the blind procedure of D&C. In the 1970s, dramatic improvements in optical systems, light sources, and distension media allowed the widespread use of hysteroscopy for accurate diagnosis (and often treatment) of intrauterine pathology.

In the 1980s, the development of hysteroscopes with smaller diameters (<4mm) allowed the use of the hysteroscope for diagnosis without the need for either cervical dilation or anaesthesia. As a result, office hysteroscopy has become a common procedure, which has been documented to have the advantages of patient acceptability, diagnostic accuracy, and cost- effectiveness.¹⁷ Hysteroscopy is particularly useful for identifying focal lesions, which are often missed with endometrial sampling.¹⁸

HYSTEROSCOPIC POLYPECTOMY

Endometrial polyps are benign growths found within the uterine cavity. They are often asymptomatic and can perhaps remain undetected for decades. In women without symptoms, polyps are often found coincidentally when pelvic ultrasonography is performed for unrelated problems such as pain or during the investigation for infertility.

Polyps are often symptomatic. However, in women with abnormal uterine bleeding, investigation may lead to their detection. Symptoms most often related to uterine polyps include abnormal bleeding, postcoital staining, chronic vaginal discharge, or dysmenorrhea. Polyp-related bleeding is often characterized by increased clotting, intermenstrual or premenstrual spotting, or heavier menstrual flow. There is good evidence that polyps can decrease fertility and that their removal will improve the chances of pregnancy.²¹

In addition to women with abnormal bleeding and infertility, other women at increased risk for endometrial polyps include women on tamoxifen therapy and women with endocervical polyps, a quarter of whom will also have endometrial polyps.

It is obvious that symptomatic endometrial polyps should be removed. However, it is also important to remove asymptomatic polyps, particularly in postmenopausal women.²² Although the vast majority are benign, endometrial cancer and hyperplasia will be found in approximately 2% of endometrial polyps and are associated with coexisting malignancies elsewhere in the endometrium. In one study of more than 1400 polyps, endometrial cancer was found in 27 polyps (1.8%).²² All but one of these women were postmenopausal, and 26% were asymptomatic.

HYSTEROSCOPIC MYOMECTOMY

Leiomyomas are the primary indication for more than 40% of the 650,000 hysterectomies performed annually in the United States.²³ Submucosal myomas likely account for 10% to 20% of all myomas. Many of these can be removed by operative hysteroscopy. In addition to preserving fertility in many cases, a hysteroscopic approach is associated with a shorter recovery period, lower complication rate, and lower cost than hysterectomy.

For a successful surgical outcome, it is important to identify preoperatively the size, number, location, and depth of intramural extension of uterine myoma. Myoma size, number, and location are determinants of complete resectability, the number of surgical procedures necessary for complete resection, the duration of surgery, and the potential complications from fluid overload.²⁴

Numerous studies have demonstrated that preoperative saline infusion sonohysterography gives more information than hysteroscopy in respect of myomas. Chapter 30 reviews the topic of ultrasonography and sonohysterography in detail.

Hysteroscopic Classification of Myomas

A classification system is important to most accurately determine the appropriate method for performing myomectomy and counseling the patient on risk and prognosis. The European Society of Hysteroscopy classification system is based on myoma location and the amount of myoma protruding or encroaching on the endometrial cavity.²⁵ In this system, Type 0 myomas are pedunculated, with the myoma lying completely within the endometrial cavity (Fig. 42-1). Type I myomas are described as sessile, with less than 50% intramural extension (Fig. 42-2). Finally, Type II myomas are submucosal in location, with more than 50% intramural extension. These include transmural myomas, which extend from the submucosal to the serosal edge. When viewed hysteroscopically, Type II myomas appear as a “bulge” into the endometrial cavity. Multiple myomas such as those in Figure 42-3 are not placed within this classification. They should not accessed by hysteroscopy.

Figure 42-1 Hysteroscopic view of a type 0 myoma. It is pedunculated and the total myoma lies within 100% of the endometrial cavity.

Figure 42-2 Hysteroscopic view of a type I myoma that involves less than 50% of the myometrium.

Figure 42-3 Extirpated uterus showing a large (6 cm) intracavitary myoma with multiple intramural and submucous myomas.

This system was originally designed to classify myomas exclusively on hysteroscopic appearance. However, this approach has significant limitations. During hysteroscopy, myomas can be compressed and recede into the myometrium as a result of the pressure of the distension media, thereby preventing full visualization of the myoma. For this reason, preoperative evaluation with ultrasonography is required to accurately determine how many myomas are present and how deeply the myomas penetrate the myometrium.

An ultrasonographic classification system has been developed for intramural myomas that corresponds in part to the hysteroscopic classification and in part to the hysterosalpingography data²⁶ (Table 42-1).

• Class 1 myomas are intracavitary and do not involve the myometrium. The base or stalk is visible on saline infusion sonohysterography (Fig. 42-4).

• Class 2 myomas have a submucosal component that involves less than 50% of the myometrium (Fig. 42-5).

• Class 3 myomas have an intramural component greater than 50%. They can be transmural and located anywhere from the submucosal to the serosa. These myomas often appear as a bulge or indentation into the submucosal when viewed hysteroscopically (Fig. 42-6).

Table 42-1 Hysteroscopic and Sonohysterographic Classification System for Myomas Encroaching Upon the Endometrial Cavity

Hysteroscopic Type25	Sonohysterographic Class26	Description
Type 0	Class 1	Pedunculated myomas, where 100% of the myoma lies within the endometrial cavity with no intramural extension
Type I	Class 2	Sessile myomas, with <50% intramural extension
Type II	Class 3	Submucous myomas, with >50% intramural extension

Figure 42-4 Class 1 myomas are intracavitary and do not involve the myometrium. The base or stalk is visible with saline infusion sonohysterography.

Figure 42-5 Class 2 myomas have a submucosal component that involves less than 50% of the myometrium.

Figure 42-6 Class 3 myomas have an intramural component greater than 50%.