Ultrasound-Guided Unification of Noncommunicating Uterine Cavities

INTRODUCTION

Müllerian anomalies occur in approximately 1 in 400 women¹ and have been associated with reproductive failure and pelvic pain from endometriosis and hematometra. Noncommunicating uterine cavities pose a challenge to the surgeon performing a hysteroscopic metroplasty because the position of the hysteroscope in relation to the cervix and ipsilateral uterine cavity is not known. Ultrasound-guidance may aid the surgeon in the treatment of this specific type of anomaly.

CASE REPORT

This report was completed after approval by the institutional review board. A 22-year-old G3 P0030 female with a history of 3 consecutive pregnancy losses presented with secondary dysmenorrhea. The past surgical history was significant for a laparoscopy performed by the patient's local physician after a Müllerian anomaly was suspected at the time of a miscarriage. The laparoscopy revealed a heart-shaped outer appearance of the uterus. Hysteroscopy performed at the same surgery revealed 2 uterine cavities with 2 tubal ostia separated by a septum. A pelvic examination showed 2 cervical ostia. An MRI revealed complete duplication of the endometrial canal with normal kidneys and bladder. Sonohysterography cannulating both cervical ostia documented noncommunicating right and left uterine cavities. The septal thickness varied from 5.8 mm near the internal cervical os to 8.6 mm at the fundus (Figure 1). The uterine cavities deviated laterally at the fundus with a normal myometrial thickness.

Figure 1.

Preoperative sonohysterographic image of the 2 uterine cavities.

Laparoscopy and hysteroscopy were performed with the patient under general anesthesia. The urinary bladder was distended with a triple lumen catheter. A speculum was placed in the vagina, and the 2 cervical ostia were visualized. The right cervix was grasped with a single tooth tenaculum. A uterine manipulator (Kronner Medical Manufacturing, Cooper Surgical, Shelton, CT) was placed in the left uterine canal and indigo carmine was instilled. The right cervix was dilated to admit a 22 F operative hysteroscope (Karl Storz, Endoscopy America Inc, Culver City, CA) through which the right uterine cavity was visualized and the right tubal ostia identified.

Under transabdominal ultrasound-guidance (ATL HDI 5000 Ultrasound System, Bothell, WA), the wall between the 2 uterine cavities was incised at its narrowest point above the internal cervical os with a resectoscope until indigo carmine overflowed into the right-sided cavity (Figure 2). The incision was extended to the fundus and the internal os. A concomitant laparoscopy revealed a heart-shaped uterus, normal tubes, and ovaries. Minimal endometriosis was identified on the right uterosacral ligament and left ovary, which was treated with a laser. Chromopertubation revealed bilateral patency of the fallopian tubes. A balloon uterine stent (Cook OB/GYN, Spencer, IN) was placed inside the uterus, instilled with 2.5 cc of saline, and left in place for 1 week. Postoperative sonohysterography performed a few months after the surgery revealed an arcuate uterine cavity.

Figure 2.

Hysteroscopic view at resection of the uterine septum. The image was taken immediately after the ipsilateral uterine cavity was entered in the lower uterine segment. The septum is identified in the midline.

DISCUSSION

The uterus and cervix are derived embryologically from paired Müllerian ducts that fuse medially to form the uterine isthmus and cervix. The fundal portion of the uterus is created by rapid proliferation of cells from the medial walls of the ducts into a septum followed by resorption. Anomalies of the uterus result from abnormal fusion of the Müllerian ducts or from failure of absorption of the septum. This patient's anomaly consisted of an externally divided fundus, a well-formed septum, and cervical duplication. Thompson et al² noted at the time of surgery that in 5 out of 12 cases of double uteri, the uteri divided externally with a well-formed septum internally. Thompson et al² did not report the incidence of cervical duplication in this series; however, several case reports have described cervical duplication with or without a uterine or vaginal septum.^3–6 Although patients with double uteri may have normal reproductive outcomes, studies have demonstrated improved outcomes after correction when a history of pregnancy complications exists.^7–10

Since Ruge¹¹ reported a successful pregnancy after removal of a septum in 1884, many procedures have been described for the treatment of Müllerian anomalies. Alternative methods to resect the septum have been described by Strassmann,¹² Tompkins,¹³ and Jones⁸ with numerous modifications.¹⁴ The surgical management of M00FC;llerian anomalies has evolved since the first descriptions, being modified due to evolving techniques. The choice of technique is influenced by vascularity of the incision, trauma to remaining myometrium, and soundness of the uterine scar.^7,14 Theoretically, a minimal amount of myometrial tissue should be removed with the repair. Hysteroscopic metroplasty has the benefits of minimal myometrial tissue disruption and outpatient care. The benefits of ultrasound-guided hysteroscopic metroplasty have been well described for a partially sep-tate uterus.¹⁵

The use of ultrasonography at the time of intrauterine surgery provides visualization of the intrauterine instruments as well as the myometrium and septum. In this case, ultrasound identified the area of the septum to incise hysteroscopically. The area initially incised was the narrowest width above the internal os of the cervix. The internal cervical os was identified sonographically at the angle of the cervix with the uterine body.

Although a small series did not find a high risk of cervical incompetence with resection of the cervical septum,¹⁶ the theoretical risk of cervical incompetence remains.¹⁷ In addition, in this patient, unification of the cervices would have been technically difficult due to the wide separation of the ostia. Alternatively, this procedure could be performed blindly with the guidance of a uterine sound or cervical dilator; however, the direction of the resection and relationship to the cervix is less obvious than with ultrasound. In summary, the use of ultra-sound may aid the surgeon in entering a noncommunicating uterine horn during a hysteroscopic metroplasty.