A Randomized Comparison of Laparoendoscopic Single-Site Hysterectomies: Total Laparoscopic Hysterectomy Versus Laparoscopically Assisted Vaginal Hysterectomy

Abstract

Background:

To compare surgical outcomes of two procedures for laparoendoscopic single-site (LESS) hysterectomy: total laparoscopic hysterectomy (TLH) and laparoscopically assisted vaginal hysterectomy (LAVH).

Materials and Methods:

Seventy-six patients who had an indication for hysterectomy for benign uterine disease were randomized to LESS-TLH or LESS-LAVH. Surgical outcomes were assessed and compared between the two groups.

Results:

There were no differences in baseline demographics between the two groups. Surgical outcomes such as operative time, estimated blood loss, length of hospital stay, and complication rate were similar between the two groups. The failure rate in the LESS-TLH group was higher than that in the LESS-LAVH group (5/38 [11%] versus 0/38 [0%]), although this difference did not reach statistical significance (P=.054). Among the 5 cases that failed in the LESS-TLH group, 4 were related to a large lower uterine segment prohibiting visualization during colpotomy. The postoperative pain scores at 18 and 36 hours after surgery were significantly lower in the LESS-TLH group than in the LESS-LAVH group (all P<.001). Vaginal discharge at 1 and 4 weeks after surgery was significantly lower in the LESS-TLH group than in the LESS-LAVH group (all P<.001).

Conclusions:

LESS-TLH and LESS-LAVH are both safe, feasible procedures with similar surgical outcomes. LESS-TLH was associated with less postoperative pain and less postoperative vaginal discharge, whereas LESS-LAVH may be preferred in patients with a uterus with a large lower uterine segment.

Introduction

Hysterectomy is one of the most common gynecologic operations worldwide.^1,2 Laparoscopic hysterectomy is currently accepted as a safe and efficient procedure with several advantages such as quicker recovery, less postoperative pain, shorter hospital stay, lower complication rates, better cosmesis, and improved quality of life over abdominal hysterectomy.^3–5 In general, laparoscopic hysterectomy is classified into two categories, depending on the extent of the procedure performed laparoscopically compared with that performed vaginally⁶: total laparoscopic hysterectomy (TLH) and laparoscopically assisted vaginal hysterectomy (LAVH). In TLH, the entire procedure is completed laparoscopically with no vaginal component except for removal of the uterus. In LAVH, the laparoscopic component does not involve ligation of the uterine vessels, which are secured during the vaginal component. Several studies have compared these two surgical procedures in terms of surgical outcomes. However, the optimal approach to laparoscopic hysterectomy has not been defined.^4,7

Technologic advances in endoscopic instrumentation and optics have allowed the development of a procedure that is even less invasive than conventional laparoscopic hysterectomy using multiple ports: laparoendoscopic single-site (LESS) surgery.⁸ Both LESS-TLH and LESS-LAVH are currently feasible^9,10 and are comparable to conventional laparoscopic hysterectomy using multiple ports.^11,12 However, there has been no study comparing the surgical outcomes between these two procedures. Therefore, we designed this randomized trial to compare surgical outcomes of LESS-TLH and LESS-LAVH to determine the advantages and disadvantages of these two minimally invasive hysterectomy procedures.

Materials and Methods

Study design and participants

This study was conducted prospectively between May 2013 and April 2014 in the Department of Obstetrics and Gynecology at the CHA Gangnam Medical Center (Seoul, Republic of Korea). Women with an indication for hysterectomy for presumed benign uterine disease were asked to participate in this study. Inclusion criteria were as follows: age ≥18 years, absence of pregnancy at the time of presentation, and appropriate medical status for laparoscopic surgery (American Society of Anesthesiologists Physical Status classification 1 or 2). Exclusion criteria were as follows: uterine volume >18 weeks of gestation by pelvic examination, suspicion of malignancy, pelvic organ prolapse greater than stage 1 according to the POP-Q classification,¹³ or an inability to understand and provide written informed consent.

Before randomization, all eligible subjects received standardized information about the trial verbally and in writing from a clinician. A study nurse who was not involved in the randomization procedure prepared sequentially numbered, opaque, sealed envelopes containing the assigned intervention to ensure that the sequence was concealed. To minimize the risk of a patient predicting treatment assignment, randomization was performed in permuted blocks of four with random variation of the blocking number. As subjects entered the operation room they were randomly assigned to undergo either LESS-TLH or LESS-LAVH in a 1:1 ratio with the use of a computer-generated schedule. The treatment protocol was approved by the Institutional Review Board of the CHA Gangnam Medical Center. The study was performed in accordance with the protocol.

Study treatment

All surgical procedures were performed by the one surgeon (T.S.), who had performed more than 50 procedures of LESS-TLH¹⁴ and LESS-LAVH.¹⁵ All subjects underwent the same standard preparation prior to surgery. General anesthesia with endotracheal intubation was achieved, and subjects were placed in the Trendelenburg position. After uterine sounding and cervical dilation, a RUMI^® uterine manipulator with a Koh Colpotomizer™ and Colpo-Pneumo Occluder™ (Cooper Surgical, Inc., Trumbull, CT) was fixed onto the cervix to effectively construct a surgical field. Using an open Hasson approach, a 1.5–2-cm vertical incision was made within the umbilicus. After insertion of a single multichannel port into the wound opening, a pneumoperitoneum was created following insufflation with carbon dioxide to a pressure of 14 mm Hg. A LigaSure™ (Covidien/Valleylab, Boulder, CO) was used as the main electrosurgical instrument for tissue coagulation and transection. Conventional monopolar and bipolar devices were sometimes used for additional cutting and hemostasis.

LESS-TLH

The LESS-TLH procedure used in our treatment protocol has been previously reported.¹⁴ In brief, after pneumoperitoneum was induced, a 5-mm laparoscope was inserted through a channel of the umbilical port, and the entire abdominal cavity was inspected carefully. With medial or lateral traction of the distal portion of the Fallopian tube, either the infundibulopelvic or utero-ovarian ligament was secured and divided with the LigaSure system, depending on whether or not the ovary was preserved. To expose the lateral aspect of the uterus, the uterine body was retracted medially with a laparoscopic forceps or a myoma screw. The round ligament was then transected, and the anterior and posterior leaves of the broad ligament were separated. Next, the vesicouterine peritoneal fold was identified, and the bladder was mobilized by blunt and sharp dissection using the LigaSure system until the anterior vagina was identified, while the uterine manipulator was pushed cephalad and posterior by an assistant. The uterine vessels were skeletonized, sealed, and transected using the LigaSure system or a bipolar device while the uterus was mobilized to the opposite side with the uterine manipulator and laparoscopic forceps or a myoma screw. The cardinal and uterosacral ligaments were then transected. This procedure was repeated on the opposite side.

After a Colpo-Pneumo Occluder's balloon was insufflated with 50 mL of normal saline to preserve adequate pneumoperitoneum, a circumferential colpotomy was completely performed with a monopolar device over the Colpotomizer cup. The specimen was removed via the vagina. Vaginal morcellation with a scalpel was performed as necessary to facilitate removal of a large uterus through the vagina. The vaginal cuff was laparoscopically sutured with one or two running polyglactin 910 (Vicryl^®; Ethicon, Somerville, NJ) sutures. After bleeding was controlled, the umbilical port system was removed, and the transumbilical fascia, subcutaneous tissue, and skin were approximated and closed layer-by-layer with Vicryl sutures.

LESS-LAVH

The LESS-LAVH procedure used in our treatment protocol has been previously reported.¹⁶ In brief, either the infundibulopelvic ligaments or utero-ovarian ligaments were secured and divided by the LigaSure system or with unipolar and bipolar electrosurgical units, depending on whether or not the ovary was preserved. When the round and broad ligaments were transected bilaterally and bleeding was controlled, surgery commenced via a vaginal approach. The anterior and posterior aspects of the cervix were grasped together with two tenacula, and a circumferential incision was made at the junction of the vagina and cervix. The cervix was then retracted caudad and posteriorly, and the anterior subvaginal tissues, including the supravaginal septum and the bladder, were grasped with an Allis clamp and elevated in the midline. The supravaginal septum was incised sharply using curved scissors and dissected bluntly using a finger. This created the vesicouterine space, the appropriate avascular cleavage plane for allowing access to the anterior peritoneum. Next, the posterior cul-de-sac was exposed by a posterior culdotomy, and the rectum was displaced from the dissected region using a right-angle retractor. Uterosacral ligaments and uterine vessels were clamped, cut, and ligated.

After these procedures, the uterus was completely isolated and removed by wedge resection, coring, and morcellation. After hemostasis was obtained, closure of the peritoneum was performed using a continuous absorbable suture in a purse-string fashion. The vaginal cuff was transvaginally closed with one or two running Vicryl sutures. After completion of all procedures, the transumbilical fascia, subcutaneous tissue, and skin were closed as described in the LESS-TLH procedure.

Outcome measures

A specific form was designed to prospectively collect data, including patient characteristics, intraoperative details, surgical outcomes, and perioperative complications. The operative time was defined as the time from skin incision to skin closure, which was recorded electronically. Estimated blood loss was calculated by the anesthesiologist as the difference between the total amount of serosanguineous fluid obtained by suction and irrigation before and after surgery, plus the difference between the total gauze weight before and after surgery. Failure of operation was defined by the use of additional ports (i.e., conversion to multiport surgery), conversion to laparotomy, or conversion to LESS-LAVH in cases of LESS-TLH. Postoperative pain assessment was performed using a visual analog scale at 18 and 36 hours after surgery by several assessors who were independent of the study investigators. The scale was presented as a 10-cm line anchored by verbal descriptors of “no pain” and “pain as bad as it could be.” Length of hospital stay was defined as the day from operation to discharge.

Subjects were scheduled for hospital follow-up at 1, 4, and 12 weeks after surgery. All intraoperative and postoperative complications arising within 12 weeks of surgery were recorded. Subjective symptoms of postoperative vaginal discharge were obtained at 1 and 4 weeks after surgery via self-reported questionnaires. Questions were evaluated on a 1–10 scale, ranging from “none” to “very much,” with higher scores indicating a greater amount of discharge. Questionnaires were collected at each visit by independent assessors who were blinded to treatment conditions before the patients saw their clinician.

Statistical analysis

Parameters of technical feasibility were considered as the major statistical end points of this study. Given that the technical feasibility of a novel surgical procedure is primarily assessed through comparison of the operative time for each procedure,^17,18 sample size was calculated based on the difference in operative time. Data from 50 consecutive patients who underwent LESS-LAVH in our department before initiation of this study (authors' unpublished data) showed an operative time of 96±28 minutes. With a type I error of 0.05, a power of 80%, and a predicted dropout rate of 10%, in total, 38 subjects in each group were required to demonstrate a 20% difference in the duration of surgery. No interim analysis was planned or performed.

SPSS version 20.0 software (SPSS Inc., Chicago, IL) was used for statistical analysis. All analyses were performed according to the intention-to-treat principle. Mean±standard deviation or median (95% confidence interval) was used for continuous variables, and frequency (percentage) was used for categorical variables. Student's t test or Mann–Whitney tests were used for comparison for means or medians for continuous variables, and the chi-squared test or Fisher's exact test was used for bivariate analysis of categorical variables. A value of P<.05 was considered statistically significant.

Results

Subjects were enrolled between May 2013 and January 2014. Follow-up visits concluded in April 2014. Of 83 subjects who were invited to participate in this study, 3 declined participation, and 4 were ineligible based on exclusion criteria. Thus, 76 subjects underwent randomization (Fig. 1). These subjects were randomly assigned to receive either LESS-TLH or LESS-LAVH. No study subject requested change of her assigned surgery or withdrew from the study after randomization.

FIG. 1.

Enrollment, randomization, and follow-up of study subjects. LAVH, laparoscopically assisted vaginal hysterectomy; LESS, laparoendoscopic single-site; TLH, total laparoscopic hysterectomy.

Baseline characteristics, including age, body mass index, marital status, parity, history of prior vaginal delivery, history of prior abdominal surgery, menopausal status, comorbidities, and level of preoperative hemoglobin, were similar between the two study groups (Table 1). The mean age and body mass index of the study participants were 45.2±5.4 years and 23.7±3.8 kg/m², respectively. The main indication for hysterectomy, the procedure performed, and adhesiolysis did not differ between the study groups.

Table 1.

Baseline Characteristics

	LESS-TLH (n=38)	LESS-LAVH (n=38)	P value
Age (years)	45.4±4.5	45.0±6.1	.767
Body mass index (kg/m²)	23.7±3.9	23.7±3.8	.979
Parity			>.999
Nulliparous	4 (11%)	5 (13%)
Parous	33 (89%)	34 (87%)
Vaginal delivery history	25 (66%)	25 (66%)	>.999
Abdominal surgery history	17 (45%)	14 (37%)	.484
Menopause	3 (8%)	2 (5%)	>.999
Comorbidities^a	5 (13%)	6 (16%)	.744
Preoperative serum hemoglobin (mg/dL)	12.0±1.6	11.9±1.9	.796
Uterine axis (cm)^b
Long	10.9±1.9	11.1±1.9	.561
Short	8.1±2.1	8.1±1.8	.896
Indication for surgery			>.999
Uterine myoma or adenomyosis	34 (90%)	34 (90%)
Endometrial pathology	3 (8%)	2 (5%)
Cervical pathology	1 (3%)	2 (5%)
Procedure performed			.843
Hysterectomy alone	26 (68%)	27 (71%)
With adnexal surgery	11 (29%)	9 (24%)
With other pelvic surgery^c	1 (3%)	2 (5%)
Adhesiolysis	9 (24%)	11 (29%)	.602

Data are expressed as mean±standard deviation, median (95% confidence interval), or frequency (percentage) as indicated.

Comorbidities included diabetes, hypertension, heart disease, and stroke.

The diameter of the uterus was measured by transvaginal ultrasonography before surgery.

Other pelvic surgeries included transobturator tape operation, labioplasty, and posterior colporrhaphy.

LAVH, laparoscopically assisted vaginal hysterectomy; LESS, laparoendoscopic single-site surgery; TLH, total laparoscopic hysterectomy.

Surgical outcomes are shown in Table 2. The mean operative time for the LESS-TLH and LESS-LAVH groups was 95.8.±20.7 minutes and 91.2±18.2 minutes, respectively, with no statistical difference. Estimated blood loss, change in serum hemoglobin level, need for transfusion of blood products, and length of hospital stay were similar between the two groups. Most LESS-TLH procedures were successful, but 5 (13%) failed: 4 cases with a uterus with large lower uterine segment were converted to LESS-LAVH to complete the procedure, and in 1 case of severe adhesions in the area of the posterior cul-de-sac, the surgery was converted to multiport TLH. Among subjects initially assigned to the LESS-LAVH group, none was converted to any other surgical approach. Therefore, the failure rate in the LESS-TLH group was higher than that in the LESS-LAVH group (13% versus 0%), although this difference did not reach statistical significance (P=.054).

Table 2.

Surgical Outcomes

	LESS-TLH (n=38)	LESS-LAVH (n=38)	P value
Operative time (minutes)	95.8±20.7	91.2±18.2	.310
Uterine weight (g)	337.9±150.6	324.7±160.1	.713
Estimated blood loss (mL)	103.2±81.5	104.0±72.5	.970
Serum hemoglobin change (g/dL)	1.6±0.7	1.6±0.8	.942
Transfusion	1 (3%)	1 (3%)	>.999
Failure of operation	5 (13%)	0	.054
Conversion to multiport surgery^a	1 (3%)	0
Conversion to LESS-LAVH	4 (11%)	—
Conversion to laparotomy	0	0
Postoperative pain score after surgery^b
At 18 hours	3.0±0.4	3.9±0.8	<.001
At 36 hours	2.2±0.6	3.1±0.9	<.001
Number of parenteral analgesics given	1 (0–5)	1 (0–4)	.628
Length of hospital stay (days)	3 (2–5)	3 (2–5)	.753
Intraoperative complications	0	0	>.999
Postoperative complications	3 (8%)	0	.240
Vaginal cuff bleeding	1 (3%)	0
Vaginal cuff infection	1 (3%)	0
Vesicovaginal fistula	1 (3%)	0
Postoperative vaginal discharge after surgery^c
At 1 week	2.0±1.1	3.7±1.3	<.001
At 4 weeks	1.9±1.0	3.4±1.5	<.001

Data are expressed as mean±standard deviation, median (95% confidence interval), or frequency (percentage) as indicated.

Conversion to multiport surgery means that the surgery required the use of additional port(s).

Postoperative pain score was measured by a visual analog scale, ranging from “no pain” to “pain as bad as it could be.”

Postoperative vaginal discharge was evaluated according to a 1–10 scale, ranging from “none” to “very much,” with higher scores indicating greater discharge.

LAVH, laparoscopically assisted vaginal hysterectomy; LESS, laparoendoscopic single-site surgery; TLH, total laparoscopic hysterectomy.

The postoperative pain scores at 18 and 36 hours were significantly lower in the LESS-TLH group than in the LESS-LAVH group (P<.001 and P<.001, respectively). However, the number of rescue analgesics requested did not differ between the two groups.

No significant intraoperative complications were observed in either group.

There were 3 cases of postoperative complications in the LESS-TLH group and no cases in the LESS-LAVH group (P=.240). All 3 subjects (8%) who experienced postoperative complications had a problem in the vaginal vault after LESS-TLH. One case of vaginal cuff bleeding that occurred 14 days after surgery was managed with vaginal packing. A case of vaginal cuff infection that developed 9 days after surgery was treated with intravenous antibiotics. One case of a vesicovaginal fistula that developed 5 weeks after surgery required laparoscopic surgical repair and resolved without sequelae. Vaginal discharge at 1 and 4 weeks after surgery was significantly lower in the LESS-TLH group than in the LESS-LAVH group (P<.001 and P<.001, respectively).

Discussion

In this randomized trial, we found that treatment of benign uterine diseases with LESS-TLH or LESS-LAVH was both feasible and safe, with similar surgical outcomes. We also found that each procedure had its merits and faults. Compared with LESS-LAVH, LESS-TLH was associated with less postoperative pain and less postoperative vaginal discharge. Conversely, LESS-LAVH was more feasible in cases where LESS-TLH seemed impossible due to a uterus with a large lower uterine segment. To the best of our knowledge, this is the first study to compare the surgical outcomes of LESS-TLH and LESS-LAVH.

Pain after surgery is a critical issue because of its connection to length of hospital stay, time to return to normal activities, and patient satisfaction. This study demonstrated that postoperative pain at 18 and 36 hours after surgery was significantly lower in the LESS-TLH group compared with the LESS-LAVH group. There are several possible explanations for our results. First, unlike LESS-TLH, LESS-LAVH frequently requires application of vigorous downward traction on the uterus. Second, we used the LigaSure system to coagulate and dissect tissues during LESS-TLH, whereas the vaginal phase of LESS-LAVH was performed using clamps, scissors, and tying of knots, according to traditional vaginal surgical techniques. Previous studies have consistently shown that implementation of the LigaSure system in vaginal surgery results in a significant reduction in postoperative pain.^19–21

In this trial, LESS-LAVH was associated with more vaginal discharge compared with LESS-TLH. This might be due to the technique of transvaginal cuff closure in which the approximated edges of the vaginal cuff is everted into the lumen of the vagina. When subjects who underwent LESS-LAVH were followed up 1 week after surgery, or in some cases at 4 weeks after surgery, speculum examination revealed a tissue reaction at the vault suture site, with mild or moderate vaginal discharge. Because this study is the first to evaluate and compare postoperative vaginal discharge following LAVH or TLH, there are no references in the literature for a direct comparison. However, if our LAVH procedure is treated as a vaginal hysterectomy in which the round ligaments and ovarian pedicles are separated laparoscopically and most parts of the hysterectomy are performed vaginally, our results are in agreement with the results of a study by Cho et al.²² in which patients who underwent vaginal hysterectomy reported more vaginal discharge, compared with patients who underwent TLH.

Our results showed that LESS-LAVH might be more feasible for a uterus with a large lower uterine segment. During the LESS-TLH procedure, circumferential colpotomy over the rim of the Koh cup is one of the most important techniques. It is feasible when the rim of the Koh cup is fully identified and the contour of the rim is exposed over the pelvic peritoneum. In the case of a large uterus, especially in the posterior aspect, a circumferential colpotomy is very difficult or even impossible to perform. In this study, 4 subjects who had a uterus with a large lower uterine segment were also converted from LESS-TLH to LESS-LAVH. Therefore, we think that LESS-LAVH has the advantage of serving as a back-up approach in cases where LESS-TLH is technically impossible.

In this trial, all complications (n=3) developed in the LESS-TLH group and were due to a problem in the vaginal vault. In fact, TLH has been reported as a significant risk factor for vaginal vault problems, compared with other modes of hysterectomy.^23–26 Extensive tissue destruction caused by thermal injury at the time of colpotomy with an electrosurgical device makes the vaginal cuff vulnerable to bleeding, impaired healing, dehiscence, and fistula formation. To avoid or lessen such vaginal cuff complications, some authors advocate the use of topical injection of a vasoconstrictor at the colpotomy site, followed by a sharp colpotomy with a laparotomic scalpel.²⁴ Therefore, surgeons should be careful to avoid thermal necrosis when they cut the vagina laparoscopically, especially during LESS-TLH.

The limitations of this randomized trial are as follows. First, all procedures were performed by one surgeon, and the results may not be applicable to other surgeons. Our findings need to be validated by other surgeons and at other institutions. Second, we were unable to perform our study in a double-blind fashion. However, although the surgeon was aware of the group assignments at the time of surgery, only independent assessors who were blinded to treatment conditions had access to questionnaires. Third, a large sample size is needed to evaluate postoperative complications, and long-term follow-up is needed to provide robust data, although this trial was not powered to investigate complications of LESS surgery.

In conclusion, our study suggests that LESS-TLH and LESS-LAVH are both feasible and safe approaches for the management of benign uterine diseases and have similar surgical outcomes. LESS-TLH was associated with less postoperative pain and less postoperative vaginal discharge compared with LESS-LAVH. LESS-LAVH may be preferred in cases with a uterus with a large lower uterine segment. Multicenter, prospective, randomized clinical trials are warranted to validate the results of this study.

Footnotes

Disclosure Statement

No competing financial interests exist.

References

Wilcox

, Koonin

, Pokras

, Strauss

, Xia

, Peterson

. Hysterectomy in the United States, 1988–1990. Obstet Gynecol, 1994; 83:549–555.

Cardenas-Goicoechea

, Soto

, Chuang

, Gretz

, Randall

. Integration of robotics into two established programs of minimally invasive surgery for endometrial cancer appears to decrease surgical complications. J Gynecol Oncol, 2013; 24:21–28.

Sokol

, Green

. Laparoscopic hysterectomy. Clin Obstet Gynecol, 2009; 52:304–312.

Nieboer

, Johnson

, Lethaby

, et al. Surgical approach to hysterectomy for benign gynaecological disease. Cochrane Database Syst Rev, 2009;(3):CD003677.

Nieboer

, Hendriks

, Bongers

, Vierhout

, Kluivers

. Quality of life after laparoscopic and abdominal hysterectomy: A randomized controlled trial. Obstet Gynecol, 2012; 119:85–91.

Mettler

, Ahmed-Ebbiary

, Schollmeyer

. Laparoscopic hysterectomy: Challenges and limitations. Minim Invasive Ther Allied Technol, 2005; 14:145–159.

Reich

, Roberts

. Laparoscopic hysterectomy in current gynecological practice. Rev Gynaecol Pract, 2003; 3:32–40.

Fader

, Cohen

, Escobar

, Gunderson

. Laparoendoscopic single-site surgery in gynecology. Curr Opin Obstet Gynecol, 2010; 22:331–338.

Jung

, Kim

, Lee

, et al. The feasibility of scarless single-port transumbilical total laparoscopic hysterectomy: Initial clinical experience. Surg Endosc, 2010; 24:1686–1692.

10.

Lee

, Kim

, et al. Single-port access laparoscopic-assisted vaginal hysterectomy: A novel method with a wound retractor and a glove. J Minim Invasive Gynecol, 2009; 16:450–453.

11.

Jung

, Lee

, Yim

, et al. A randomized prospective study of single-port and four-port approaches for hysterectomy in terms of postoperative pain. Surg Endosc, 2011; 25:2462–2469.

12.

Kim

, Lee

, Cha

, et al. Single-port-access laparoscopic-assisted vaginal hysterectomy versus conventional laparoscopic-assisted vaginal hysterectomy: A comparison of perioperative outcomes. Surg Endosc, 2010; 24:2248–2252.

13.

Abrams

, Cardozo

, Fall

, et al. The standardisation of terminology of lower urinary tract function: Report from the Standardisation Sub-committee of the International Continence Society. Neurourol Urodyn, 2002; 21:167–178.

14.

Song

, Lee

, Kim

, et al. Single-port access total laparoscopic hysterectomy for large uterus. Gynecol Obstet Invest, 2013; 75:16–20.

15.

Song

, Kim

, et al. Single port access laparoscopic-assisted vaginal hysterectomy for large uterus weighing exceeding 500 grams: Technique and initial report. J Minim Invasive Gynecol, 2010; 17:456–460.

16.

Song

, Kim

, Lee

, et al. What is the learning curve for single-port access laparoscopic-assisted vaginal hysterectomy?. Eur J Obstet Gynecol Reprod Biol, 2011; 158:93–96.

17.

Reichenbach

, Tackett

, Harris

, et al. Laparoscopic colon resection early in the learning curve: What is the appropriate setting?. Ann Surg, 2006; 243:730–735; discussion 735–737.

18.

Dath

, Regehr

, Birch

, et al. Toward reliable operative assessment: The reliability and feasibility of videotaped assessment of laparoscopic technical skills. Surg Endosc, 2004; 18:1800–1804.

19.

Hefni

, Bhaumik

, El-Toukhy

, et al. Safety and efficacy of using the LigaSure vessel sealing system for securing the pedicles in vaginal hysterectomy: Randomised controlled trial. BJOG, 2005; 112:329–333.

20.

Silva-Filho

, Rodrigues

, Vale de Castro Monteiro

, et al. Randomized study of bipolar vessel sealing system versus conventional suture ligature for vaginal hysterectomy. Eur J Obstet Gynecol Reprod Biol, 2009; 146:200–203.

21.

Gizzo

, Burul

, Di Gangi

, et al. LigaSure vessel sealing system in vaginal hysterectomy: Safety, efficacy and limitations. Arch Gynecol Obstet, 2013; 288:1067–1074.

22.

Cho

, Park

, Kim

, Kang

, Park

. Surgical outcome and cost comparison between total vaginal hysterectomy and laparoscopic hysterectomy for uteri weighing >500 g. J Minim Invasive Gynecol, 2014; 21:115–119.

23.

Hur

, Donnellan

, Mansuria

, Barber

, Guido

, Lee

. Vaginal cuff dehiscence after different modes of hysterectomy. Obstet Gynecol, 2011; 118:794–801.

24.

Hur

, Guido

, Mansuria

, Hacker

, Sanfilippo

, Lee

. Incidence and patient characteristics of vaginal cuff dehiscence after different modes of hysterectomies. J Minim Invasive Gynecol, 2007; 14:311–317.

25.

Uccella

, Ghezzi

, Mariani

, et al. Vaginal cuff closure after minimally invasive hysterectomy: Our experience and systematic review of the literature. Am J Obstet Gynecol, 2011; 205:119 e111–119 e112.

26.

Kim

, Kim

, Bae

, Lee

, Song

. Evaluation of risk factors of vaginal cuff dehiscence after hysterectomy. Obstet Gynecol Sci, 2014; 57:136–143.