子宫纵隔宫腔镜手术（图文演示）

HYSTEROSCOPIC   SURGERY   OF   SEPTATE   UTERUS
Authors
R de Tayrac, H Fernandez, A Gervaise
Abstract
The description of the hysteroscopic surgery of septate uterus covers all aspects of the surgical procedure used for the management of septate uterus (uterine malformation).
Operating room set up, position of patient and equipment, instruments used are thoroughly described. The technical key steps of the surgical procedure are presented in a step by step way: adjustment of system, operative steps, special cases, end of procedure.
Consequently, this operating technique is well standardized for the management of this condition.


中文版：子宫纵隔宫腔镜手术（中文图文演示）

1. Introduction
Diagnostic hysteroscopy is the gold standard for exploring the uterine cavity in cases of infertility, menometrorrhagia or repeated miscarriage. The intracavitary pathology revealed during the examination (uterine malformations, polyps, myomas and adhesions) can be treated by surgical hysteroscopy.
Septate uterus is the most common uterine malformation. The development of surgical hysteroscopy has simplified the treatment of this pathology, which used to be treated by laparotomy and hysterectomy (Valle and Sciarra, 1986; De Cherney et al., 1986; March and Israël, 1987). Surgical hysteroscopy using rigid scissors attached to a channel is no longer performed. Today, this pathology is treated using monopolar electrosurgery. Bipolar electrosurgery, which was introduced more recently, seems to be as effective and results in less morbidity (Fernandez, 1998).

2. Anatomical pathology

Septate uterus is caused by an anomaly during organogenesis. It is a lack of resorption of the tissue separating the 2 embryonic halves of the uterus (the Müllerian ducts), which are joined on the midline. Normally, the resorption of this septum occurs caudad to cephalad: it begins at the level of the cervix and continues up to the uterine fundus. This resorption anomaly can occur at different stages of Müllerian duct development, between the 11th and 16th weeks of gestation, accounting for various resorption defects ranging from the completely septate uterus (sometimes with 2 cervices and a vaginal septum), partially septate uterus or simple fundic spurs. This malformation is never combined with another anomaly of the genitourinary organs.

1. Round ligament
2. Uterine tube
3. Uterine septum
4. Proper ovarian ligament
5. Uterine cavity
6. Endometrium
7. Myometrium
8. Mesometrium of broad ligament
9. Uterine artery
10. Ureter
11. Cervical canal
12. Uterosacral ligament
13. External uterine opening
14. Vagina

3. Classifications

In France, the classification of Musset is most commonly used (Musset et al., 1967).
Elsewhere, the 1988 classification of the American Fertility Society (AFS) is most widely accepted. These classifications may be summarized as follows:

Müllerian aplasias
The Musset classification lists Müllerian aplasias as:
- bilateral: Mayer-Rokitansky-Kuster-Hauser syndrome;
- unilateral: unicornuate uterus (without rudimentary horn), pseudo-unicornuate uterus (with rudimentary horn).
The AFS classification lists Müllerian aplasias as:
Class I: Hypoplasia, agenesis
Class II: Unicornuate uterus

Fusion defects
The Musset classification lists fusion defects as:
- dideolphys uterus (complete or partial duplication of the vagina, cervix and uterus);
- bicornuate uterus: complete (septum from fundus to cervical os), partial (septum to body of uterus), partial (septum confined to the fundus).
The AFS classification lists fusion defects as:
Class III: Dideolphys uterus
Class IV: Bicornuate uterus

Resorption defects
The Musset classification lists resorption defects as:
Septate uterus: complete, partial, to body of uterus, confined to the fundus
The AFS classification lists resorption defects as:
Class V: Septate uterus
Vb: Complete
Va: Partial

4. Indications
Formal indications
- pregnancy complications such as second-trimester loss or preterm delivery
Possible indications
- recurrent first-trimester spontaneous abortion

Controversial indications
- before in-vitro fertilization (as preventative treatment)

Contraindications
- contraindications to anesthesia;
- genitourinary infections;
- pregnancy;
- bicornuate uterus.

5. Preop period

The preoperative workup is important and includes hysterography, diagnostic hysteroscopy and pelvic sonography. Vaginal sonography with accentuated contrast may be added. These exams should confirm that the patient has a septate uterus and not a bicornuate uterus, and check for other causes of infertility.
During the sonography, it is essential to measure the thickness of the uterine septum, its height and the depth of the healthy myometrium above the septum up to the serosa. If the ultrasound reveals a groove in the corner facing the posterior surface of the bladder between two half-uteri, the malformation is diagnosed as a bicornuate uterus.
A 1-month preoperative progestogen treatment (eg pregnane) or the administration of GnRH analogs (gonadotropin releasing hormone) can be prescribed to prepare the endometrium. The procedure should then be performed about 28 days after starting the treatment.

6. Operating room set-up
• Patient

- general anesthesia, local-regional anesthesia or paracervical block anesthesia;
- lithotomy position: legs spread at a 45° angle, thighs at a 90° angle from the surface of the table and knees bent at a 90° angle;
- perineal and cervicovaginal preparation;
- prophylactic antibiotics when anesthesia is induced to prevent endometritis;
- urinary catheter (optional).

• Team

1. The surgeon is seated between the patient’s legs.
2. The assistant stands to the right of the surgeon.
3. The anesthesiologist is at the patient’s head.

• Equipment

The equipment is on the surgeon’s left:
- endocamera and monitor;
- devices to control pressure and flow of distension media: a constant uterine distension must be maintained. The pressure is controlled continually by suction and irrigation pumps;
- distension medium: hyperosmolar glycine solution with monopolar cautery, saline with bipolar cautery;
- light source: the same type of Xenon light source is used for diagnostic hysteroscopy, surgical hysteroscopy and laparoscopy;
- high-frequency electrosurgical generator:
1) unipolar electrosurgery: high-frequency current is used (>300 000 Hz). Division of tissues is done with an unmodulated current that produces a rapid rise in temperature.
2) bipolar electrosurgery: saline is used as the distension medium to decrease the risk of metabolic complications. The operating channel is 5 French.

7. Instruments

Usual equipment:
1. Hegar’s dilators (No. 1 to No. 10, diameter increasing from 0.5 to 1 mm);
2. Speculum with detachable valves;
3. Rigid endoscope between 2.7 and 4 mm in diameter; the direction of view normally used in hysteroscopy is 12°.
4. Resectoscope: from 7 to 9 mm with two channels, one internal (irrigation) and one external (suction) for monopolar hysteroscopy, or from 5 to 9 mm with two channels and a double current operation channel for bipolar hysteroscopy. In all cases it has an operative handle: passive (electrode in) or active (electrode out);
5. Hysteroscope;
6. Irrigation and suction channels;
7. Two Pozzi graspers;
8. Hysterometer.

8. Major principles

Cutting current is used for dissection. The septum should be divided but not removed, to avoid destroying the endometrium. The procedure is performed under constant visual guidance and consists of transversally dividing the uterine septum halfway between the 2 uterine surfaces, until the 2 tubal ostia can be visualized in the same hysteroscopic field.

9. Adjustment of system

Monopolar system
The resection techniques described use monopolar current. The suction-irrigation pump must be preset to maintain an intrauterine pressure <=100 mm Hg, a 250 mL/s flow rate, a 0.2 bar suction pressure and 45 W of power. The procedure must not last longer than 45 minutes. The total volume of glycocolle used must be limited to 6 L. Precise monitoring of the distension liquid inflow and outflow must be done, and the procedure must be stopped immediately if there is a difference between the irrigation and suction flow rates (a 500 mL difference can be allowed). If there is too much of a difference, or if the procedure lasts too long, a chemistry panel must be performed immediately after the procedure to check for metabolic complications (hyponatremia).

Bipolar system
Bipolar spray electrosurgery is a more recent system. Its efficacy seems to be equivalent to monopolar electrosurgery, with a decrease in morbidity. The suction-irrigation pump should be preset to maintain a flow of 150 mL/s, a pressure of 80 mm Hg and 100 W or less of power. There are no limits to the duration of the procedure.
Bipolar systems have the advantage of being safer, because they can be used with saline, thereby decreasing metabolic complications. In contrast to the monopolar system, which penetrates into the tissues and can be partly obscured at certain points, the bipolar system is constantly visible. This lowers the risk of uterine perforation.