Hysteroscopy

Anatomy and Physiology

External genitalia: These anatomical structures are visible on inspection and do not require speculum examination. They include the mons pubis, clitoris, urethral meatus, vestibule of the vagina, labia majora and minora, vaginal opening, hymen, perineum, and anus. The external female genitalia is collectively known as the vulva. 

Vagina: The muscular canal that connects the vulva to the cervix. It is an elastic passageway that varies in length and width. It functions as a source of sexual pleasure and a route for fetal delivery. It also conducts the passage of sperm after intercourse and blood during menses. 

Cervix: The opening from the vagina to the uterus. It is usually 2 or 3 cm long. The cervix has a central opening called the cervical canal flanked by the external os anteriorly and the internal os posteriorly. Canal width varies throughout a female’s life, with maximal dilation to around 10cm during childbirth. 

Uterus corpus: The uterus lies midline within the pelvis between the bladder anteriorly and the rectum posteriorly. It usually lies in an anteverted and anteflexed position. Version refers to the position of the cervix relative to the vagina, and flexion refers to the position of the fundus relative to the cervix. The fallopian tubes connect to the uterine corpus at the fundus bilaterally, with tubal ostia able to be visualized on hysteroscopy.

Indications

The most common indications for hysteroscopy are as follows:[11]

• Suspicion of the intracavitary lesion 
• Abnormal uterine bleeding
• Abnormal endometrial thickening 
• Postmenopausal bleeding
• Infertility 
• Mullerian congenital anomaly
• Removal of foreign bodies

Whenever possible, in-office hysteroscopy is preferred. Compared to surgical inpatient hysteroscopy, in-office hysteroscopy offers many potential benefits, including patient and physician convenience, avoidance of general anesthesia, higher patient satisfaction, faster recovery, and cost-effectiveness (ACOG Committee Opinion 800). Factors that challenge outpatient hysteroscopy feasibility include large intrauterine pathology, patient anxiety, lack of appropriate treatment setting and/or personnel, and physician skill and expertise.[12][13]

Contraindications

Absolute contraindications to hysteroscopy are few. They include active pelvic infection, prodromal or active genital herpes, and confirmed cervical or endometrial cancer. Moderate vaginal bleeding is a relative contraindication to hysteroscopy. However, adequate visualization for the procedure may be achieved with copious irrigation. Pregnancy is also a contraindication to hysteroscopy unless used in the setting of retained IUD or products of conception removal.

Medical comorbidities could be potential contraindications to hysteroscopic surgery(e.g., coronary heart disease, bleeding diathesis). 

Equipment

Hysteroscopes

There are several types of hysteroscopes available for diagnostic and operative purposes that deserve further explanation. The two main types of hysteroscopes are flexible and rigid. Hysteroscopes are available at viewing angles ranging from 0 to 70 degrees. They all easily connect to fluid channels, a light source, and a video monitoring system. A continuous flow of distending media is needed for optimal visualization of the endometrial cavity. Most hysteroscopes have an operative channel that permits the passage of surgical instruments such as small hysteroscopic graspers, scissors, or a tenaculum. 

• STORZ Bettocchi integrated in-office hysteroscope: this hysteroscope has a small diameter of 4mm (Bettocchi 4) or 5 mm (Bettocchi 5) with an oval tip that permits easy passage through the cervix, which is especially important when used in an office setting with conscious patients. It features 2.1 mm (Bettocchi 4) and 2.9 mm (Bettochi 5) 12 and 30 degrees optics and a working channel for 5 French semi-rigid operative instruments. 
• STORZ Campo Trophyscope: this hysteroscope has an outer diameter of 2.9 mm, permitting even easier passage through the cervix due to the smaller diameter of the scope. However, with the Trophyscope, the intraoperative changeover is necessary to a continuous flow examination sheath is necessary. This sheath is 3.7 mm in diameter. It features a 30-degree scope with a working operative channel that allows for the introduction of 5 French semi-rigid instruments and bipolar electrodes.
• Olympus Flexible Hysteroscope: this hysteroscope has a flexible outer tip with a wide 100-degree tip angulation range that the operator may adjust. It is 3.1 mm in diameter. It features a wide field of view and an instrument channel. 

There are other types of rigid diagnostic and operative hysteroscopes that range in diameter and degree of viewing angulation. In addition, the resectoscope and mini-resectoscope offer easy manipulation of electrocautery monopolar and bipolar loop devices that can be loaded into the scope, providing an easier dissection through dense tissue.[14]

Distension Medium

Adequate distention of the uterus is imperative to performing hysteroscopy. Fluid or gas (carbon dioxide) may be used. However, carbon dioxide is only used during diagnostic hysteroscopies because visibility is lost with bleeding.[3] Fluid distension media allow the irrigation of the cavity for better visualization. With operative hysteroscopy and the electrical current loops used for dissection, fluid media must be carefully chosen. Fluid-containing electrolytes must not be utilized with monopolar current due to the risk of energy dispersal to surrounding tissues. When bipolar instruments are used, electrolyte-rich fluid-distending media, such as normal saline, may be selected. [15]

Other Instruments

The traditional hysteroscopic entry technique requires a tray with instruments for cervical dilation. These instruments and materials include a metal speculum, cervical tenaculum, sound, cervical dilators, ring forceps, and raytecs. Local anesthesia, if needed, might be selected based on operator preference. Preferred options include 1% or 2% lidocaine with or without epinephrine. A long 25 or 27-gauge needle is needed for the administration of anesthetic into the cervix.[16] With vaginoscopy and the no-touch technique, there is no need for instruments apart from the hysteroscope.[17]

Personnel

Personnel needed depends on the setting in which hysteroscopy is undertaken. In the operating room, personnel includes a dedicated anesthesiologist and/or certified nurse anesthetist, nurses for pre and post-operative care, nurses and techs for operating room and supply maintenance, scrub techs, and transport staff.[18] 

In the office, the number of staff needed is significantly reduced. Dedicated patient monitoring requires a staff member who is qualified to do so other than the physician. The presence of a team member with ACLS certification and capabilities is highly recommended. Another consideration for in-office hysteroscopy is the accessibility of equipment for treating cardiovascular emergencies and anaphylaxis. Dedicated anesthesia personnel is not needed in the office since the procedure is usually performed with only local or no anesthesia.[19]

Preparation

Preparation for hysteroscopy includes preoperative evaluation and testing individualized for patient needs. Further testing for preoperative clearance should be undertaken if comorbid conditions exist that increase operative morbidity. Hysteroscopy may be performed at any time in postmenopausal women. For premenopausal women, it is important to consider that performing hysteroscopy during the secretory phase of the menstrual cycle may lead to overdiagnosis of endometrial polyps since the endometrium may appear polypoid during this time (ACOG Committee Opinion 800). Using misoprostol for cervical dilation pre-procedure is not universally accepted and is not routinely performed.[20] 

Prophylactic antibiotics are not needed for hysteroscopy.[21] A thorough history and physical should be performed on every patient before performing a hysteroscopy.[22] In addition, a preoperative pregnancy test should be performed on all premenopausal women. Currently, there is no consensus on pain management for in-office hysteroscopy. Different protocols, both pharmacologic and non-pharmacologic, have been proposed.[23] Informed consent, including a discussion of risks, benefits, and alternatives, should always be obtained prior to any surgical procedure.[24][25][26]

Technique or Treatment

First, as with any gynecologic procedure, the appropriate positioning of the patient must be ensured. The patient is positioned in the dorsal lithotomy position, taking care to avoid unnecessary pressure that may cause nerve injury. The table must be flat; Trendelenberg positioning should be avoided. The bimanual examination should always be performed before the start of any gynecologic procedure. An indwelling Foley catheter is not necessary; however, a straight catheter may be used to drain the bladder before starting the procedure. Next, the hysteroscope is set up, the camera is white-balanced and focused, and the inflow tract is primed. With the vaginoscopic entry technique, the need for the traditional instruments used for entry is avoided. The provider begins vaginoscopy by introducing the hysteroscope into the vagina. The vagina is then distended, and the cervix and external os may be located by gently advancing the scope. The posterior fornix is usually easily identified. Once the external os is located, the hysteroscope is carefully inserted and passed through the internal os into the uterine cavity. With the traditional techniques, a speculum is first inserted. The cervix is visualized and grasped anteriorly with a single-tooth tenaculum. The cervix is then dilated to the diameter of the hysteroscope being used, after which the hysteroscope is inserted. At the same time, counter traction is applied with the tenaculum to straighten the uterus. 

Once inside the uterus, the entire uterine cavity may be inspected. Any pathology can be quickly identified, and a plan made for the operation. The bilateral tubal ostia should be identified at the beginning of the case. 

Further technique varies depending on the type of intrauterine pathology. We will focus on the operative technique as it applies to fibroids, polyps, adhesions, and retained intrauterine devices. AUB is the most common indication for hysteroscopy with structural abnormalities such as polyps and/or fibroids, usually as root causes.[27]

Hysteroscopic myomectomy can be performed in numerous ways. Submucosa myomas are accessible by operative hysteroscopy and are divided into types 0, I, and II based on their distribution within the myometrium. Type 0 is fully intracavitary, type I is mostly intracavitary, and type II is mostly myometrial. Since type 0 fibroids are usually pedunculated, they may be resected easily depending on their size, using sharp dissection, electrocautery, or a loop dissection device.[28] Type I and Type II myoma resection often requires two surgical procedures to achieve full resection. The excision of only the intracavitary portion of a fibroid is not recommended due to its propensity for intracavitary regrowth. Resectoscopic progressive excision followed by interval complete excision after the fibroid spontaneously migrates into the cavity has been shown to be one successful strategy.[5] Some studies show the higher success of total removal of intrauterine pathology with these systems with no significant difference in complication rates. However, a higher fluid deficit was reported in the tissue removal system group.[27]

Pretreatment with GnRH agonists to shrink fibroids and correct anemia is not universally performed. Small studies have shown the benefits of GnRH agonist use for submucosal fibroids greater than 3 cm for a period ranging from 6 weeks to 4 months. However, this drug class causes unpleasant side effects, including hot flashes, decreased libido, and insomnia. One recent retrospective study found treatment before surgery was associated with longer surgical times and increased cervical resistance. Consider shared decision-making and patient individualization before prescribing medical pretreatment.[5] Hysteroscopic polypectomy can be carried out with operative microscissors or monopolar or bipolar electrocautery. Non-hysteroscopic polypectomy, such as with polyp forceps, has a higher recurrence rate than hysteroscopic polypectomy.[29] With mechanical tissue removal systems as described above, data show increased rates of complete resection of pathology and shorter operation time for resection of polyps.[27]

With hysteroscopy, it has become possible to remove a uterine septum or, in other words, perform a uterine septoplasty. Likewise, the resection of intrauterine adhesions spurred by a history of endometrial trauma is termed hysteroscopic adhesiolysis. These two abnormalities are associated with infertility and can be remedied with resection as long as they do not re-form. A Cochrane review published in 2017 suggests limited evidence for medical or IUD treatment in operative hysteroscopy to prevent intrauterine adhesion formation.[30]

Hysteroscopy is a safe and effective method for retrieval of retained and/or embedded devices, the most common of which are intrauterine devices (IUDs). It may even be used in the first trimester of pregnancy to retrieve IUDs when strings cannot be seen on the pelvic exam. Pregnancies with retained IUD are associated with increased rates of miscarriage, preterm delivery, and chorioamnionitis. Hysteroscopic removal for retained IUD is an emerging option for treatment, especially when ultrasound-guided removal is not feasible.[31][32]

Most patients tolerate diagnostic and operative hysteroscopy well and can be discharged from the postoperative recovery unit or office setting soon after the completion of the procedure. Vaginal spotting and discomfort are common. Recommendations for the timing of pelvic rest vary by provider, with some saying that normal activities may resume in 24 hours, especially when the vaginoscopy “no-touch” entry technique is used. A follow-up appointment should be arranged before discharge for an anticipatory review of pathology results.

Complications

Overall, hysteroscopy is regarded as a safe, minimally invasive procedure. [33]

Uterine Perforation

The most common reported complication of both diagnostic and operative hysteroscopy is uterine perforation.[34] Perforation can occur at any point during the procedure but is more common with resection extending into the uterine myometrium.[35] Encountered in about one percent of cases, uterine perforation may be managed conservatively or operatively, depending on patient status. Hemodynamic status should first be assessed with low suspicion for vascular injury if perforation was caused by blunt dissection. If the patient is hemodynamically stable and there is low suspicion of vascular or visceral damage, there is no need for laparoscopy or exploratory laparotomy. Prolonged postoperative same-day recovery is recommended with strict pain, bleeding, and fever precautions and close clinical follow-up.[36] 

Bleeding alone without uterine perforation may be encountered with deep dissection into the myometrium and intersection with a perforating vessel. This complication is more common with operative hysteroscopy and the removal of type I and type II subserosal fibroids. Bleeding may be managed with electrocautery, uterotonics such as oxytocin, or foley balloon catheter placement to be left inside the uterus to tamponade bleeding.[36]

Fluid Overload

Complications pertaining to distension media used in hysteroscopy deserve detailed discussion. The fluid deficit is carefully calculated intraoperatively to quantify the amount of fluid the patient is absorbing into their circulation. Of particular concern is the risk of hyponatremia and resulting cerebral edema, especially when electrolyte-free hypotonic solutions are used. Cerebral edema may manifest with symptoms of nausea and or vomiting, dizziness, shortness of breath, or headache. The mechanism of fluid absorption has to do with the amount of intrauterine pressure created by hysteroscopic fluid management systems and the venous absorption of distending media.[33] Some institutions recognize this as operative hysteroscopy intravascular absorption syndrome (OHIA).

Electrolyte-rich isotonic fluid, such as normal saline, may be used with bipolar systems. As such, bipolar systems have less risk of fluid overload syndromes. In healthy women, hysteroscopy should be aborted if the fluid deficit exceeds 2500mL when isotonic distention media is used and 1000 mL with hypotonic media. In women with comorbidities such as cardiac or pulmonary conditions that compromise hemodynamic stability, the surgeon should consider termination of the procedure with a fluid deficit of 1000mL and 750mL of an isotonic and hypotonic solution, respectively. Avoidance of OHIA can be achieved with close monitoring of fluid status. Patients at risk for OHIA may be identified beforehand by assessing estimated procedure time, risk for incomplete resection of intrauterine pathology, and the existence of comorbidities.

Embolism 

Hysteroscopy can result in carbon dioxide embolism if it is used as the distending media. This complication can be catastrophic if it occurs due to the potential for cardiac failure leading to death. Limited studies show a wide-ranging air embolism rate from 10 to 50% with the use of carbon dioxide.[37] If this complication is suspected, the anesthesia team should immediately advise the surgeon, and the procedure should be terminated. Durant’s position (patient placement in left lateral decubitus and Trendelenberg) may assist in the migration of air away from the right ventricular outflow tract. If cardiac arrest occurs, cardiac catheterization may be performed with the goal of relieving the embolized air from the cardiovascular system. This iatrogenic complication of hysteroscopy may be prevented by using fluid-distending media and priming equipment by releasing air from tubing and avoiding excessive instrumentation, which may introduce air into the genital tract.

Clinical Significance

The gold standard for the diagnosis and treatment of intrauterine pathology is hysteroscopy. As such, this technique has numerous indications and benefits. Hysteroscopy can improve quality of life, treat infertility, remove foreign bodies, or diagnose malignancy. Women with abnormal uterine bleeding may experience significant improvement in symptoms post hysteroscopic resection of pathology, avoiding the need for invasive surgical procedures such as hysterectomy.[38] 

Also, compared to blind endometrial sampling, direct visualization of the entire uterine cavity and biopsy with hysteroscopy allows for targeted sampling and complete resection of uterine abnormalities such as polyps. These have the potential for malignancy, especially in postmenopausal women and women with a family history of gynecologic cancer. Further, ambulatory hysteroscopy offers appeal with the potential avoidance of general anesthesia or conscious sedation. Studies comparing in-office hysteroscopy to operating room hysteroscopy show comparable patient acceptance and outcomes along with decreased cost.[39]

Enhancing Healthcare Team Outcomes

If hysteroscopy is performed in the ambulatory or inpatient operating room setting, more personnel must be included in the interprofessional healthcare team. Technicians and representatives should confirm all proper functioning of equipment needed before the patient enters the operating room. Scrub technicians are essential in pre-preparing equipment, so delays and malfunctions may be limited. The final patient assessment before surgery should always be prompted by the circulator or other operating room staff and include a pelvic examination. It is essential to brief each team member about each case; this occurs on multiple levels and culminates with a time-out before the procedure is undertaken.

Anesthesia should direct patient positioning to avoid dislodging endotracheal tubes, lines, and other monitoring systems. Throughout the procedure, appropriate attention to surgical undertakings is needed from the scrub tech and circulator in order to maintain adequate lighting, fluid balance, and distending media pressure. Equipment adjustments may also be needed, such as in the display monitors or electrocautery instruments. Inattention to detail may have severe consequences, as described above. At the procedure end, all fluids in, fluids out, blood loss, and urine output is documented and announced by the circulator nurse. Anesthesia must continue to monitor hemodynamic and respiratory statuses after extubation or weaning from sedation. However, it is important to remember that all healthcare team members are responsible for working together to ensure the patient's safety. 

Effective communication between nursing staff in the pre-, intra-, and post-operative units is key to patient treatment. If all members of the nursing staff are kept up to date on patient status and events, this creates a much safer patient environment, especially with surgical management. 

In-office hysteroscopy does not need to consist of more than two to three personnel. The surgeon may be semi-self-sufficient, and a scrub tech is not required. However, thorough equipment understanding and review are required by the provider. In academic centers, in-office hysteroscopy offers more involvement for residents and medical students, as personnel is reduced, but assistance may be needed to ensure smooth operation in the awake patient. Patient comfort and assurance are of utmost importance. The right demeanor in an in-office hysteroscopy team can ease anxiety and improve outcomes.