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Back to Journal »International Journal of General Medicine» Volume 14

Comparison of laparoscopic uterine artery occlusion and non-uterine artery occlusion in the treatment of symptomatic multiple myomas

Authors: Peng Yan, Cheng Jie, Zang C, Chen Xu, Wang Jie

Published on May 5, 2021, Volume 2021: 14 pages, 1719-1725 pages

DOI https://doi.org/10.2147/IJGM.S310864

Single anonymous peer review

Editor who approved for publication: Dr. Scott Fraser

Peng Yanzhen, Cheng Jiumei, Zang Chunyi, Chen Xi, Wang Jinxue, Department of Minimally Invasive Gynecology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, 100006 Corresponding author: Jiumei Cheng, Department of Obstetrics and Gynecology, Beijing, Minimally Invasive Gynecology Hospital of Capital Medical University, Beijing 17 Qihelou Street, Dongcheng District, 100006 Tel 86 18600245876 Email [email protected] Purpose: Uterine artery occlusion (UAO) is a minimally invasive method commonly used to treat symptomatic uterine fibroids. This study aimed to compare the clinical effects of laparoscopic UAO (LUAO) combined with laparoscopic myomectomy (LM) and LM alone in the treatment of symptomatic multiple uterine fibroids. Method: This is a prospective observational study. From April 2015 to October 2017, a total of 122 symptomatic patients with multiple uterine fibroids received LUAO LM or LM. Operation time, blood loss, maximum postoperative temperature, hospital stay, number of fibroids removed, surgical complications, and the recurrence rate of the two groups were compared. Results: The average blood loss of the LUAO LM group was significantly lower than that of the LM group (177.97 ± 104.09 mL vs 258.10 ± 119.55 mL, p <0.05). There were no significant differences between the LUAO LM group and the LM group in terms of operation time, hospital stay, postoperative maximum body temperature, and surgical complications. The number of myomas removed in the LUAO LM group was significantly higher than that in the LM group (4[4-7] vs 3[3-5], p <0.05). The recurrence rate of the LUAO LM group was significantly lower than that of the LM group (6.2% vs 25.9%). Conclusion: Compared with LM alone, LUAO combined with LM has higher surgical quality and lower fibroids recurrence rate. For women with symptomatic multiple uterine fibroids who wish to preserve the uterus, it is recommended to use LUAO in combination with LM. Keywords: laparoscopic myomectomy, uterine artery occlusion, uterine fibroids

Uterine fibroids are the most common benign tumors of the female reproductive system, and the incidence of women of childbearing age is 20-40%. 1 Patients with symptomatic fibroids usually experience menorrhagia, pelvic pain, urinary tract and/or intestinal pressure, and infertility. Surgical methods are still the main method of treating symptomatic fibroids. 2 Although hysterectomy, as a conventional treatment method, provides a clear therapeutic effect for women who do not want to preserve fertility, there is a trend to preserve the uterus and adopt minimally invasive methods in the surgical treatment of uterine fibroids. 1 In addition, with the improvement of surgeons' skills and the development of laparoscopic instruments, laparoscopic myomectomy (LM) has been widely used for patients who wish to preserve the uterus without considering the preservation of fertility.

Although LM has the advantages of shorter hospital stay (LOS), faster postoperative recovery, and better cosmetic effects than open surgery, the complications related to surgery cannot be ignored. Factors such as excessive intraoperative blood loss, prolonged operation time, and increased possibility of recurrence of fibroids are often encountered. Therefore, in recent years, LM combined with permanent or temporary laparoscopic uterine artery occlusion (LUAO) has been advocated. More and more evidence confirms that positive clinical results after LM LUAO can reduce intraoperative blood loss and risk of recurrence. 3,4 However, based on the following concepts, most previous studies only focused on uncomplicated LM diameters greater than 8 cm or multiple leiomyomas (>3), laparotomy may be more appropriate. 5,6 A recent study found that uterine preservation and the use of minimally invasive methods are the most important changes in the surgical treatment of uterine fibroids during development. Endoscopic surgery has gradually replaced the traditional laparotomy. 1

This observational study aims to evaluate the safety and effectiveness of LM LUAO in the treatment of symptomatic women with multiple uterine fibroids compared with LM alone.

This study is a prospective observational study of patients with symptomatic multiple myomas requiring conservative surgery at the Minimally Invasive Gynecology Center of Beijing Obstetrics and Gynecology Hospital from April 2015 to October 2017. Transvaginal ultrasound was diagnosed as uterine fibroids. Record the characteristics of the fibroids, such as the type, number, location (front, back, bottom) and diameter of the dominant fibroids, and the three diameters of the uterus. The formula for calculating the volume of the uterus is: (upper and lower diameter × anterior and posterior diameter × left and right diameter) × 0.523. Symptoms caused by fibroids include menorrhagia, frequent urination, and pain-like sensations. The inclusion criteria for this study are as follows: Two or more symptomatic intramural fibroids (FIGO type 3, 4, 5, 6), regardless of concurrent subserosal fibroids (FIGO type 7), 7 no previous Abdominal or pelvic surgery, and a strong desire to preserve the uterus. Postoperative pathological results confirmed that patients with submucosal fibroids or malignant conditions were excluded.

Finally, 112 consecutive patients were recruited and their general characteristics (age and body mass index [BMI]) and maternal medical history were recorded. Before surgery, all patients received diagnostic tests to rule out other diseases. Patients who did not wish to preserve fertility received LM combined with UAO (LM LUAO group, n = 64), while those who wished to preserve fertility received LM alone (LM group, n = 58). All operations are performed by a surgeon. Written informed consent of each patient was obtained, and all patients were followed up regularly for two years after the operation.

All patients were placed in a dorsal incision site and a bladder catheter was inserted. Tracheal intubation induces general anesthesia. The uterine manipulator is used to allow movement of the uterus. After the laparoscopic surgical field is established, the intra-abdominal pressure is maintained between 12 and 14 mmHg and CO2 is used.

For patients in the LUAO LM group, the first step of surgery is bilateral uterine artery occlusion. In most cases, a 3 cm incision is made in the posterior lobe of the broad ligament above the uterosacral ligament about 2 cm from the isthmus of the uterus. There are two other methods for peritoneal incision. The first method is to make an incision in the triangular area of ​​the broad ligament (surrounded by the round ligament, the pelvic funnel ligament and the external iliac blood vessels), and the second method is to make an incision in the anterior lobe of the broad ligament. Broad ligament (Figure 1). The choice of incision approach depends on the size of the uterus, the location and size of the dominant fibroids, the pelvic space and the formation of pelvic adhesions. When the size of the uterus increases, the posterior wall fibroids dominate, or the formation of pelvic adhesions makes it difficult to reveal the posterior lobe of the broad ligament, the triangular area or the anterior lobe approach can be used. Whichever method is chosen, the ureters and uterine arteries are identified and carefully separated by blunt dissection. Subsequently, under direct laparoscopic vision, the uterine artery was completely occluded by coagulation with bipolar forceps with a power between 40 and 45 W. The coagulation band width is 1.0–1.5 cm. The characteristics of the uterine artery include 1-2cm above the ureter, 2-6mm in diameter, tortuous in shape, and vascular pulsation. Figure 1 Three different approaches for laparoscopic uterine artery occlusion (LUAO). (A) The anterior lobe of the broad ligament. (B) The posterior lobe of the broad ligament. (C) The triangular area in the broad ligament.

Figure 1 Three different approaches for laparoscopic uterine artery occlusion (LUAO). (A) The anterior lobe of the broad ligament. (B) The posterior lobe of the broad ligament. (C) The triangular area in the broad ligament.

The LM of the two groups of patients was performed as follows. First, under close vital signs monitoring, use a syringe to inject diluted vasopressin (3 U/100 mL) into the myometrium. Then, use a monopolar electric hook to incise the superficial myometrium and pseudocapsule until the fibroids are visible to the naked eye. Use screw clamps to fix and pull the leiomyoma, and then separate it from the uterus. Use 1-0 continuous absorbable sutures to repair myometrial defects. The resected leiomyoma was removed by an electromechanical pulverizer through a 15 mm trocar located in the lower right abdomen.

The intraoperative parameters that we considered when comparing the two groups included operation time, estimated blood loss, transit to laparotomy, number of fibroids removed, and blood transfusion. The operation time is the time from the first abdominal wall incision to the closure of all laparoscopic incisions, recorded by the anesthesiologist. The amount of blood loss is estimated based on the amount of fluid drawn and absorbed minus the amount of flushing. Several postoperative outcomes were evaluated, such as hospital LOS, hemoglobin drop (HgD) on the second day after surgery, and maximum postoperative temperature. Perioperative complications include wound infection, deep vein thrombosis, intestinal injury or obstruction, and urinary system injury.

The patients are followed up for at least two years and are required to return to the hospital every 3-6 months after the operation. The relief of symptoms related to fibroids was recorded and transvaginal ultrasound was performed. Ultrasonography confirmed that symptomatic fibroids ≥ 2 cm were considered to be recurrence of fibroids. The recurrence rate was determined two years after the operation.

SPSS Version 19.0 for Windows (SPSS Inc., Chicago, IL, USA) is used for statistical analysis. All continuous variables were tested for normality using the Kolmogorov-Smirnov test. Normally distributed variables are expressed as mean ± standard deviation, while skew variables are expressed as median and interquartile range. Parametric independent samples t test or non-parametric Mann-Whitney U test is used to compare the difference between two groups. Categorical variables are expressed as percentages and compared using Chi-square test or Fisher's exact test as appropriate. All calculated p-values ​​are two-tailed. The statistical significance level was set to a value of p<0.05.

A total of 122 patients who met the inclusion criteria and had complete surgery and follow-up data participated in the study. Among them, 64 received LUAO LM and 58 received LM alone. The demographic and clinical characteristics and fibroids parameters of the patients are shown in Table 1. There were no significant differences between the two groups in pregnancy rate, parity, BMI, main symptoms of fibroids, diameter and location of dominant fibroids, and preoperative hemoglobin levels. Table 1 Baseline demographic and clinical characteristics of patients​​

Table 1 Baseline demographic and clinical characteristics of patients​​

None of the cases needed to be converted to open surgery due to technical difficulties or intraoperative complications. There was no significant difference in operation time between LUAO LM group and LM group. However, the surgical blood loss in the LUAO LM group was significantly less than that in the LM group (177.97±104.09 mL vs 258.10±119.55 mL). The number of fibroids resected in the LUAO LM group was significantly higher than that in the LM group. During or immediately after the operation, 2 patients in the LM group required blood transfusion, while no patient in the LUAO LM group required blood transfusion.

There were no serious acute or delayed perioperative complications in both groups. The HgD on the second day after operation in the LM group was significantly lower than that in the LUAO LM group (1.33 ± 0.98 mg/dL vs 1.75 ± 1.16 mg/dL). There was no difference in the average postoperative hospital stay. The median of the LUAO LM group was 6 days (range: 2-7) and the LM group was 6 days (range: 4-9). The recurrence rate of fibroids was statistically different between the two groups. 4 patients (6.2%) in the LUAO LM group and 15 patients (25.9%) in the LM group had recurrent fibroids (see Table 2). Table 2 Surgery and postoperative results

Table 2 Surgery and postoperative results

Although non-surgical treatment strategies for symptomatic uterine fibroids have been established in recent years, such as uterine artery embolization (UAE), high-frequency magnetic resonance guided focused ultrasound surgery and medical treatment, 2,6,8 LM is still hopeful The main minimally invasive treatment option for patients who retain fertility or uterine organs. However, due to excessive intraoperative bleeding and postoperative symptomatic uterine fibroids recurrence due to technical difficulties, especially in the case of multiple uterine fibroids, LM is associated with an increased risk of disease. 6,9 UAO, a hemostatic technique, in 1999. Although there is some evidence that LUAO has advantages during myomectomy, such as reduced blood loss and lower recurrence rate, 10-12, the results are conflicting. 4 In addition, few studies have focused on its impact on patients with multiple uterine fibroids. Our study aims to explore the effect of combining LUAO and LM on the treatment of multiple uterine fibroids.

Although several previous studies have shown conflicting results regarding the efficacy of LUAO in reducing blood loss during LM surgery, a recent direct comparative meta-analysis of women with symptomatic leiomyomas with LUAO combined with LM and LM The short-term and long-term results have demonstrated a significant difference in intraoperative blood loss, indicating that LUAO may have a positive effect on reducing blood loss. 3 Our study evaluated the hemostatic effect of LUAO on LM in patients with multiple uterine fibroids. The results showed that the intraoperative blood loss of the LUAO LM group was significantly less than that of the LM group. Correspondingly, the HgD of the LUAO LM group was significantly lower than that of the LM group on the second day after surgery. Therefore, LUAO will be an effective hemostatic technique, especially for patients with multiple fibroids who have received multiple uterine incisions during surgery.

The hemostatic effect of LUAO can provide many benefits in facilitating the surgical process and reducing the morbidity associated with surgery. First of all, no excessive bleeding contributes to a clearer surgical field, making the resection of uterine fibroids more feasible and thorough. Our study confirmed this, which showed that the number of fibroids removed in the LUAO LM group was higher than that in the LM group. Second, due to the reduced need for bipolar coagulation to stop bleeding, potential electrical damage to the myometrium is minimized, which may facilitate faster recovery after surgery, as reported by Yang. 11 Third, the reduction of intraoperative blood loss can help reduce blood transfusion rates and related risks. Therefore, as an effective hemostasis technique, LUAO can be applied to other gynecological laparoscopic surgeries, such as adenomyoma resection, ectopic pregnancy at cesarean section scars, complicated hysterectomy and other surgeries that may cause excessive bleeding. 13,14

The high recurrence rate after LM is still a clinical problem that needs to be resolved, especially for multiple uterine fibroids, which has an increased risk of recurrence. 15 Several previous studies have found that LUAO LM may be more effective than LM alone to reduce the possibility of recurrence. 11,16,17 Our findings are consistent with this, because during the two-year follow-up, the recurrence rate of the LUAO LM group was significantly lower than that of the LM group (6.2% vs. 25.9%, p = 0.003). At present, there are two reasons for the recurrence of fibroids after surgery. One is the growth of residual small fibroids that cannot be detected during surgery. LUAO causes ischemia and hypoxia, necrosis of the remaining fibroids and unable to grow. A number of studies have shown that there are differences in the coagulation-fibrinolysis system and compensatory blood supply between fibroids and myometrium, leading to prolonged hypoxia duration of fibroids, but blood supply in the uterus is restored. 10,11 This may be the effect of the treatment mechanism LUAO on fibroids, which will explain the lower recurrence rate after LM. In addition, as shown in our research, due to the homeostatic effect of LUAO, a clearer surgical field is conducive to more thorough removal of fibroids, reducing the possibility of recurrence. However, it is worth noting that, as Jin reported, the short-term LUAO technique is not beneficial in reducing the recurrence of fibroids. 18 This means that only continuous hypoxia and ischemia can lead to fibroids necrosis.

Given that LUAO's effect on uterine ischemia is similar to UAE, and has been proven to cause impaired ovarian function and insufficient endometrium, concerns about the negative effects of LUAO on ovarian reserve and fertility have always existed. Although there is evidence that ovarian function is not impaired after temporary occlusion, including normal Doppler values ​​after uterine artery surgery and anti-Müllerian hormone and follicle-stimulating hormone levels,17,18 few studies have focused on permanent occlusion. Some scholars believe that whether it affects ovarian function seems to depend on the location of the uterine blood vessel blockage. As reported by Lee, 19 UAO combined with uterine and ovarian vascular anastomosis at the same time obstruction and the risk of a significant increase in follicle-stimulating hormone levels in the first month after surgery is greater than the risk of using UAO alone, which may reflect ovarian function.

Due to the lack of prospective randomized controlled studies, the true fertility consequences of receiving LUAO are still inconclusive, although some comparative studies have shown that the pregnancy rate and the percentage of surviving infants in the occluded myomectomy group compared with myomectomy alone There is no significant difference. 4,20,21 However, Michal et al. conducted a prospective non-randomized clinical trial comparing the clinical results of UAE and LUAO in the treatment of women with uterine fibroids, 22 and found that the average birth weight of newborns was lower (3270 g vs 2768 g, p = 0.013), the incidence of intrauterine growth restriction was higher in patients receiving LUAO (13% vs. 38%, p = 0.046), despite similar pregnancy outcomes (69% after UAE vs 67% after LUAO), delivery (50% vs. 46%) or abortion (34% vs. 33%) rate. This suggests that the complete closure of the main branch of the uterine artery during surgical occlusion may have a greater risk of reduced uterine and placental perfusion during pregnancy than the more selective UAE. Therefore, it is currently not recommended to routinely use this technology outside of clinical trials for patients who wish to become pregnant.

The main advantage is the first study of the effect of LM combined with LUAO on multiple fibroids and a comprehensive evaluation of intraoperative and postoperative results. Before drawing the conclusions of this study, several limitations should be discussed. First of all, this study is not prospectively randomized, leading to patient selection bias. There are differences in baseline characteristics between the two groups. Second, we treat patients according to their future reproductive wishes, which may expose the study to some expected deviations. This may lead to differences in the age of patients and the surgeon is willing to remove more fibroids when endometrial damage and uterine structure are not so important. Third, the operation is performed by a single operator. Therefore, this data may not be applicable to all operators. In view of the above limitations, our research results should be interpreted with caution.

In short, LM combined with LUAO is an effective and safe treatment for patients with multiple symptomatic intramural fibroids who wish to preserve the uterus. The main benefits of this procedure include reduced intraoperative bleeding and more thorough removal of fibroids, which may be an important factor in reducing the risk of recurrence compared with LM alone. Based on the advantages of LUAO in myomectomy for patients with multiple fibroids, a large multicenter prospective randomized controlled study should be further carried out.

This study was approved by the Ethics Committee of Beijing Obstetrics and Gynecology Hospital of Capital Medical University. This research was conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from all participants.

We would like to thank all the staff who implemented the intervention and evaluation part of this research for their hard work and professionalism.

There are no funds to report.

The authors declare that they have no competing interests.

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