Xiaoming Guan, MD, PhD

He Y, Zhong J, Zhou W, et al. Four surgical strategies for the treatment of cesarean scar defect: a systematic review and network meta-analysis. J Minim Invasive Gynecol. 2020;27:593-602.

EXPERT COMMENTARY

With the increase in cesarean deliveries performed over the decades, the sequelae of the surgery are now arising. Cesarean scar defects (CSDs) are a complication seen when the endometrium and muscular layers from a prior uterine scar are damaged. This damage in the uterine scar can lead to abnormal uterine bleeding and the implantation of an ectopic pregnancy, which can be life-threatening. Ultrasonography can be used to diagnose this defect, which can appear as a hypoechoic space filled with postmenstrual blood, representing a myometrial tear at the wound site.¹ There are several risk factors for CSD, including multiple cesarean deliveries, cesarean delivery during advanced stages of labor, and uterine incisions near the cervix. Elevated body mass index as well as gestational diabetes also have been found to be associated with inadequate healing of the prior cesarean incision.² Studies have shown that both single- and double-layer closure of the hysterotomy during a cesarean delivery have similar incidences of CSDs.^3,4 There are multiple ways to correct a CSD; however, there is no gold standard that has been identified in the literature.

Details about the study

The study by He and colleagues is a meta-analysis aimed at comparing the treatment of CSDs via laparoscopy, hysteroscopy, combined hysteroscopy and laparoscopy, and vaginal repair. The primary outcome measures were reduction in abnormal uterine bleeding and scar defect depth. A total of 10 studies (n = 858) were reviewed: 4 randomized controlled trials (RCTs) and 6 observational studies. The studies analyzed varied in terms of which techniques were compared.

Patients who underwent uterine scar resection by combined laparoscopy and hysteroscopy had a shorter duration of abnormal uterine bleeding when compared with hysteroscopy alone (standardized mean difference [SMD] = 1.36; 95% confidence interval [CI], 0.37−2.36; P = .007) and vaginal repair (SMD = 1.58; 95% CI, 0.97−2.19; P<.0001). Combined laparoscopic and hysteroscopic technique also was found to reduce the diverticulum depth more than in vaginal repair (SMD = 1.57; 95% CI, 0.54−2.61; P = .003).

Continue to: Study strengths and weaknesses...

Study strengths and weaknesses

This is the first meta-analysis to compare the different surgical techniques to correct a CSD. The authors were able to compare many of the characteristics regarding the routes of repair, including hysteroscopy, laparoscopy, and vaginal. The authors were able to analyze the combined laparoscopic and hysteroscopic approach, which facilitates evaluation of the location and satisfaction of defect repair during the procedure.

Some weaknesses of this study include the limited amount of RCTs available for review. All studies were also from China, where the rate of CSDs is higher. Therefore, the results may not be generalizable to all populations. Given that the included studies were done at different sites, it is difficult to determine surgical expertise and surgical technique. Additionally, the studies analyzed varied by which techniques were compared; therefore, indirect analyses were conducted to compare certain techniques. There was limited follow-up for these patients (anywhere from 3 to 6 months), so long-term data and future pregnancy data are needed to determine the efficacy of these procedures.

He Y, Zhong J, Zhou W, et al. Four surgical strategies for the treatment of cesarean scar defect: a systematic review and network meta-analysis. J Minim Invasive Gynecol. 2020;27:593-602.

EXPERT COMMENTARY

With the increase in cesarean deliveries performed over the decades, the sequelae of the surgery are now arising. Cesarean scar defects (CSDs) are a complication seen when the endometrium and muscular layers from a prior uterine scar are damaged. This damage in the uterine scar can lead to abnormal uterine bleeding and the implantation of an ectopic pregnancy, which can be life-threatening. Ultrasonography can be used to diagnose this defect, which can appear as a hypoechoic space filled with postmenstrual blood, representing a myometrial tear at the wound site.¹ There are several risk factors for CSD, including multiple cesarean deliveries, cesarean delivery during advanced stages of labor, and uterine incisions near the cervix. Elevated body mass index as well as gestational diabetes also have been found to be associated with inadequate healing of the prior cesarean incision.² Studies have shown that both single- and double-layer closure of the hysterotomy during a cesarean delivery have similar incidences of CSDs.^3,4 There are multiple ways to correct a CSD; however, there is no gold standard that has been identified in the literature.

Details about the study

The study by He and colleagues is a meta-analysis aimed at comparing the treatment of CSDs via laparoscopy, hysteroscopy, combined hysteroscopy and laparoscopy, and vaginal repair. The primary outcome measures were reduction in abnormal uterine bleeding and scar defect depth. A total of 10 studies (n = 858) were reviewed: 4 randomized controlled trials (RCTs) and 6 observational studies. The studies analyzed varied in terms of which techniques were compared.

Patients who underwent uterine scar resection by combined laparoscopy and hysteroscopy had a shorter duration of abnormal uterine bleeding when compared with hysteroscopy alone (standardized mean difference [SMD] = 1.36; 95% confidence interval [CI], 0.37−2.36; P = .007) and vaginal repair (SMD = 1.58; 95% CI, 0.97−2.19; P<.0001). Combined laparoscopic and hysteroscopic technique also was found to reduce the diverticulum depth more than in vaginal repair (SMD = 1.57; 95% CI, 0.54−2.61; P = .003).

Continue to: Study strengths and weaknesses...

Study strengths and weaknesses

This is the first meta-analysis to compare the different surgical techniques to correct a CSD. The authors were able to compare many of the characteristics regarding the routes of repair, including hysteroscopy, laparoscopy, and vaginal. The authors were able to analyze the combined laparoscopic and hysteroscopic approach, which facilitates evaluation of the location and satisfaction of defect repair during the procedure.

Some weaknesses of this study include the limited amount of RCTs available for review. All studies were also from China, where the rate of CSDs is higher. Therefore, the results may not be generalizable to all populations. Given that the included studies were done at different sites, it is difficult to determine surgical expertise and surgical technique. Additionally, the studies analyzed varied by which techniques were compared; therefore, indirect analyses were conducted to compare certain techniques. There was limited follow-up for these patients (anywhere from 3 to 6 months), so long-term data and future pregnancy data are needed to determine the efficacy of these procedures.

He Y, Zhong J, Zhou W, et al. Four surgical strategies for the treatment of cesarean scar defect: a systematic review and network meta-analysis. J Minim Invasive Gynecol. 2020;27:593-602.

EXPERT COMMENTARY

With the increase in cesarean deliveries performed over the decades, the sequelae of the surgery are now arising. Cesarean scar defects (CSDs) are a complication seen when the endometrium and muscular layers from a prior uterine scar are damaged. This damage in the uterine scar can lead to abnormal uterine bleeding and the implantation of an ectopic pregnancy, which can be life-threatening. Ultrasonography can be used to diagnose this defect, which can appear as a hypoechoic space filled with postmenstrual blood, representing a myometrial tear at the wound site.¹ There are several risk factors for CSD, including multiple cesarean deliveries, cesarean delivery during advanced stages of labor, and uterine incisions near the cervix. Elevated body mass index as well as gestational diabetes also have been found to be associated with inadequate healing of the prior cesarean incision.² Studies have shown that both single- and double-layer closure of the hysterotomy during a cesarean delivery have similar incidences of CSDs.^3,4 There are multiple ways to correct a CSD; however, there is no gold standard that has been identified in the literature.

Details about the study

The study by He and colleagues is a meta-analysis aimed at comparing the treatment of CSDs via laparoscopy, hysteroscopy, combined hysteroscopy and laparoscopy, and vaginal repair. The primary outcome measures were reduction in abnormal uterine bleeding and scar defect depth. A total of 10 studies (n = 858) were reviewed: 4 randomized controlled trials (RCTs) and 6 observational studies. The studies analyzed varied in terms of which techniques were compared.

Patients who underwent uterine scar resection by combined laparoscopy and hysteroscopy had a shorter duration of abnormal uterine bleeding when compared with hysteroscopy alone (standardized mean difference [SMD] = 1.36; 95% confidence interval [CI], 0.37−2.36; P = .007) and vaginal repair (SMD = 1.58; 95% CI, 0.97−2.19; P<.0001). Combined laparoscopic and hysteroscopic technique also was found to reduce the diverticulum depth more than in vaginal repair (SMD = 1.57; 95% CI, 0.54−2.61; P = .003).

Continue to: Study strengths and weaknesses...

Study strengths and weaknesses

This is the first meta-analysis to compare the different surgical techniques to correct a CSD. The authors were able to compare many of the characteristics regarding the routes of repair, including hysteroscopy, laparoscopy, and vaginal. The authors were able to analyze the combined laparoscopic and hysteroscopic approach, which facilitates evaluation of the location and satisfaction of defect repair during the procedure.

Some weaknesses of this study include the limited amount of RCTs available for review. All studies were also from China, where the rate of CSDs is higher. Therefore, the results may not be generalizable to all populations. Given that the included studies were done at different sites, it is difficult to determine surgical expertise and surgical technique. Additionally, the studies analyzed varied by which techniques were compared; therefore, indirect analyses were conducted to compare certain techniques. There was limited follow-up for these patients (anywhere from 3 to 6 months), so long-term data and future pregnancy data are needed to determine the efficacy of these procedures.

Through the years, the surgical approach to hysterectomy has expanded from its early beginnings of being performed only through an abdominal or transvaginal route with traditional surgical clamps and suture. The late 1980s saw the advent of the laparoscopic-assisted vaginal hysterectomy (LAVH), and from that point forward several additional hysterectomy methods evolved, including today’s robotic approaches.

Although clinical evidence and societal endorsements support vaginal hysterectomy as a superior high-value modality, it remains one of the least performed among all available routes.^1-3 In an analysis of inpatient hysterectomies published by Wright and colleagues in 2013, 16.7% of hysterectomies were performed vaginally, a number that essentially has remained steady throughout the ensuing years.⁴

Attempts to improve the application of vaginal hysterectomy have been made.⁵ These include the development of various curriculum and simulation-based medical education programs on vaginal surgical skills training and acquisition in the hopes of improving utilization.⁶ An interesting recent development is the rethinking of vaginal hysterectomy by several surgeons globally who are applying facets of the various hysterectomy methods to a transvaginal approach known as vaginal natural orifice transluminal endoscopic surgery (vNOTES).^7,8 Unique to this thinking is the incorporation of conventional laparoscopic instrumentation.

Although I have not yet incorporated this approach in my surgical armamentarium at Columbia University Medical Center/New York–Presbyterian Hospital, I am intrigued by the possibility that this technique may serve as a rescue for vaginal hysterectomies that are at risk of conversion or of not being performed at all.⁹

At this time, vNOTES is not a standard of care and should be performed only by highly specialized surgeons. However, in the spirit of this Update on minimally invasive surgery and to keep our readers abreast of burgeoning techniques, I am delighted to bring you this overview by Dr. Xiaoming Guan, one of the pioneers of this surgical approach, and Dr. Tamisa Koythong and Dr. Juan Liu. I hope you find this recent development in hysterectomy of interest.

—Arnold P. Advincula, MD

Continue to: Development and evolution of NOTES...

Development and evolution of NOTES 

Over the past few decades, emphasis has shifted from laparotomy to minimally invasive surgery because of its proven significant advantages in patient care, such as improved cosmesis, shorter hospital stay, shorter postoperative recovery, and decreased postoperative pain and blood loss.¹⁰  Advances in laparoendoscopic surgery and instrumentation, including robot-assisted laparoscopy (RAL), single-incision laparoscopic surgery (SILS), and most recently natural orifice transluminal endoscopic surgery (NOTES), reflect ongoing innovative developments in the field of minimally invasive surgery. 

Here, we provide a brief literature review of the NOTES technique, focus on its application in gynecologic surgery, and describe how we perform NOTES at our institution. 

NOTES application in gynecology 

With NOTES, peritoneal access is gained through a natural orifice (such as the mouth, vagina, urethra, or anus) to perform endoscopic surgery, occasionally without requiring an abdominal incision. First described in 2004, transgastric peritoneoscopy was performed in a porcine model, and shortly thereafter the first transgastric appendectomy was performed in humans.^11,12 The technique has further been adopted in cholecystectomy, appendectomy, gastrectomy, and nephrectomy procedures.¹³ 

Given rapid interest in a possible paradigm shift in the field of minimally invasive surgery, the Natural Orifice Surgery Consortiumfor Assessment and Research (NOSCAR) was formed, and the group published an article on potential barriers to accepted practice and adoption of NOTES as a realistic alternative to traditional laparoscopic surgery.¹⁴ 

While transgastric and transanal access to the peritoneum were initially more popular, the risk of anastomotic leaks associated with incomplete closure and subsequent infection were thought to be prohibitively high.¹⁵ Transvaginal access was considered a safer and simpler alternative, allowing for complete closure without increased risk of infection, and this is now the route through which the majority of NOTES procedures are completed.^16,17 

The eventual application of NOTES in the field of gynecology seemed inevitable. The American College of Obstetricians and Gynecologists stated that transvaginal surgery is the most minimally invasive and preferred surgical route in the management of patients with benign gynecologic diseases.¹⁸ However, performing it can be challenging at times due to limited visualization and lack of the required skills for single-site surgery. NOTES allows a gynecologic surgeon to improve visualization through the use of laparoendoscopic instruments and to complete surgery through a transvaginal route. 

In 2012, Ahn and colleagues demonstrated the feasibility of the NOTES technique in gynecologic surgery after using it to successfully complete benign adnexal surgery in 10 patients.¹⁹ Vaginal NOTES (vNOTES) has since been further developed to include successful hysterectomy, myomectomy, sacrocolpopexy, tubal anastomosis, and even lymphadenectomy in the treatment of early- stage endometrial carcinoma.^20-26 vNOTES also can be considered a rescue approach for traditional vaginal hysterectomy in instances in which it is necessary to evaluate adnexal pathology.⁹ Most recently, vNOTES hysterectomy has been reported with da Vinci Si or Xi robotic platforms.^27,28 

Continue to: Operative time, post-op stay shorter in NAOC-treated patients...

Few studies have compared outcomes with vNOTES to those with traditional laparoscopy. In 2016, Wang and colleagues compared surgical outcomes between NOTES-assisted ovarian cystectomy (NAOC) and laparoscopic ovarian cystectomy (LOC) in a case-matched study that included 277 patients.²⁹ Although mean (SD) blood loss in patients who underwent LOC was significantly less compared with those who underwent NAOC (21.4 [14.7] mL vs 31.6 [24.1] mL; P = .028), absolute blood loss in both groups was deemed minimal. Additionally, mean (SD) operative time and postoperative stay were significantly less in patients undergoing NAOC compared with those having LOC (38.23 [10.19] minutes vs 53.82 [18.61] minutes; P≤.001; and 1.38 [0.55] days vs 1.82 [0.52] days; P≤.001; respectively).²⁹ 

How vNOTES hysterectomy stacked up against TLH 

In 2018, Baekelandt and colleagues compared outcomes between vNOTES hysterectomy and total laparoscopic hysterectomy (TLH) in a noninferiority single-blinded trial of 70 women.⁸ Compared with TLH, vNOTES hysterectomy was associated with shorter operative time (41 vs 75 minutes; P<.001), shorter hospital stay (0.8 vs 1.3 days; P = .004), and lower postoperative analgesic requirement (8 vs 14 U; P = .006). Additionally, there were no differences between the 2 groups in postoperative infection rate, intraoperative complications, or hospital readmissions within 6 weeks.⁸

Approach for performing vNOTES procedures 

At our institution, Baylor College of Medicine, the majority of gynecologic surgeries are performed via either transumbilical robot-assisted single-incision laparoscopy or vNOTES. Preoperative selection of appropriate candidates for vNOTES includes: 

• low suspicion for or prior diagnosis of endometriosis with obliteration of the posterior cul-de-sac 
• no surgical history suggestive of severe adhesive disease, and 
• adequate vaginal sidewall access and sufficient descent for instrumentation for entry into the peritoneal cavity. 

In general, a key concept in vNOTES is "vaginal pull, laparoscopic push," which means that the surgeon must pull the cervix while performing vaginal entry and then push the uterus back in the peritoneal cavity to increase surgical space during laparoscopic surgery. 

Continue to: Overview of vNOTES steps...

Below we break down a description of vNOTES in 6 sections. Our patients are always placed in dorsal lithotomy position with TrenGuard (D.A. Surgical) Trendelenburg restraint. We prep the abdomen in case we need to convert to transabdominal surgery via transumbilical single-incision laparoscopic surgery or traditional laparoscopic surgery. 

1. Vaginal entry 

Accessing the peritoneal cavity through the vagina initially proceeds like a vaginal hysterectomy. We inject dilute vasopressin (20 U in 20 mL of normal saline) circumferentially in the cervix (for hysterectomy) or in the posterior cervix in the cervicovaginal junction (for adnexal surgery without hysterectomy) for vasoconstriction and hydrodissection. 

We then incise the vaginal mucosa circumferentially with electrosurgical cautery and follow with posterior colpotomy. We find that reapproximating the posterior peritoneum to the posterior vagina with either figure-of-8 stitches or a running stitch of polyglactin 910 suture (2-0 Vicryl) assists in port placement, bleeding at the peritoneal edge, and closure of the cuff or colpotomy at the end of the case. We tag this suture with a curved hemostat. 

Depending on whether a hysterectomy is being performed, anterior colpotomy is made. Again, the anterior peritoneum is then tagged to the anterior vaginal cuff in similar fashion, and this suture is tagged with a different instrument; we typically use a straight hemostat or Sarot clamp (FIGURE 1). 

2. Traditional vaginal hysterectomy 

After colpotomy, we prefer to perform progressive clamping of the broad ligament from the uterosacral and cardinal ligaments to the level of uterine artery as in traditional vaginal hysterectomy, if feasible. 

3. Single-site port placement 

The assembled GelPOINT Mini advanced access platform (Applied Medical) (FIGURE 2) is introduced through the vagina after the Alexis wound protector (included with the kit) is first placed through the colpotomy with assistance of Babcock clamps (FIGURE 3). 

After ensuring that the green rigid ring of the Alexis wound protector is contained and completely expanded within the peritoneal cavity, we cross our previously tagged sutures as we find this helps with preventing the GelPOINT Mini access platform from inadvertently shifting out of the peritoneal cavity during surgery. The GelSeal cap is then secured and pneumoperitoneum is established (FIGURE 4). 

Continue to: 4. Laparoendoscopic surgery...

Instruments used in our surgeries include a 10-mm rigid 30° 43-cm working length laparoscope; a 44-cm LigaSure device (Medtronic); a 5-mm, 37-cm laparoscopic cobra grasping forceps and fenestrated grasper (Karl Storz); and a 5-mm, 45-cm laparoscopic suction with hydrodissection tip (Stryker) (FIGURE 5). 

vNOTES allows a gynecologic surgeon the unique ability to survey the upper abdomen. The remainder of the surgery proceeds using basic laparoscopic single-site skills. 

During vNOTES, as with all single-site surgical procedures, understanding the optimal placement of crossed instruments is important for successful completion. For example, when securing the right uterine artery, the surgeon needs to push the cervix toward the patient's left and slightly into the peritoneal cavity using a laparoscopic cobra grasper with his or her left hand while then securing the uterine pedicle using the LigaSure device with his or her right hand. This is then reversed when securing the left uterine artery, where the assistant surgeon pushes the cervix toward the patient's right while the surgeon secures the pedicle ("vaginal pull, laparoscopic push") (FIGURE 6). 

This again is reiterated in securing the ovarian pedicles, which are pushed into the peritoneal cavity while being secured with the LigaSure device. 

5. Specimen removal 

For large uteri or specimens that need morcellation, a 15-mm Endo Catch specimen retrieval bag (Medtronic) is introduced through the GelPOINT Mini system. The specimen is then placed in the bag and delivered to the vagina, where contained bag morcellation is performed in standard fashion (FIGURES 7 AND 8). We utilized the "big C" technique by first grasping the specimen with a penetrating clamp. The clamp is then held in our nondominant hand and a No. 10 blade scalpel is used to create a reverse c-incision, keeping one surface of the specimen intact. This is continued until the specimen can be completely delivered through the vagina. 

Specimens that do not require morcellation can be grasped laparoscopically, brought to the GelPOINT Mini port, which is quickly disassembled, and delivered. The GelSeal cap is then reassembled. 

6. Vaginal cuff closure 

The colpotomy or vaginal cuff is closed with barbed suture continuously, as in traditional vaginal hysterectomy cuff closure. Uterosacral ligament suspension should be performed for vaginal cuff support.  
 

Through the years, the surgical approach to hysterectomy has expanded from its early beginnings of being performed only through an abdominal or transvaginal route with traditional surgical clamps and suture. The late 1980s saw the advent of the laparoscopic-assisted vaginal hysterectomy (LAVH), and from that point forward several additional hysterectomy methods evolved, including today’s robotic approaches.

Although clinical evidence and societal endorsements support vaginal hysterectomy as a superior high-value modality, it remains one of the least performed among all available routes.^1-3 In an analysis of inpatient hysterectomies published by Wright and colleagues in 2013, 16.7% of hysterectomies were performed vaginally, a number that essentially has remained steady throughout the ensuing years.⁴

Attempts to improve the application of vaginal hysterectomy have been made.⁵ These include the development of various curriculum and simulation-based medical education programs on vaginal surgical skills training and acquisition in the hopes of improving utilization.⁶ An interesting recent development is the rethinking of vaginal hysterectomy by several surgeons globally who are applying facets of the various hysterectomy methods to a transvaginal approach known as vaginal natural orifice transluminal endoscopic surgery (vNOTES).^7,8 Unique to this thinking is the incorporation of conventional laparoscopic instrumentation.

Although I have not yet incorporated this approach in my surgical armamentarium at Columbia University Medical Center/New York–Presbyterian Hospital, I am intrigued by the possibility that this technique may serve as a rescue for vaginal hysterectomies that are at risk of conversion or of not being performed at all.⁹

At this time, vNOTES is not a standard of care and should be performed only by highly specialized surgeons. However, in the spirit of this Update on minimally invasive surgery and to keep our readers abreast of burgeoning techniques, I am delighted to bring you this overview by Dr. Xiaoming Guan, one of the pioneers of this surgical approach, and Dr. Tamisa Koythong and Dr. Juan Liu. I hope you find this recent development in hysterectomy of interest.

—Arnold P. Advincula, MD

Continue to: Development and evolution of NOTES...

Development and evolution of NOTES 

Over the past few decades, emphasis has shifted from laparotomy to minimally invasive surgery because of its proven significant advantages in patient care, such as improved cosmesis, shorter hospital stay, shorter postoperative recovery, and decreased postoperative pain and blood loss.¹⁰  Advances in laparoendoscopic surgery and instrumentation, including robot-assisted laparoscopy (RAL), single-incision laparoscopic surgery (SILS), and most recently natural orifice transluminal endoscopic surgery (NOTES), reflect ongoing innovative developments in the field of minimally invasive surgery. 

Here, we provide a brief literature review of the NOTES technique, focus on its application in gynecologic surgery, and describe how we perform NOTES at our institution. 

NOTES application in gynecology 

With NOTES, peritoneal access is gained through a natural orifice (such as the mouth, vagina, urethra, or anus) to perform endoscopic surgery, occasionally without requiring an abdominal incision. First described in 2004, transgastric peritoneoscopy was performed in a porcine model, and shortly thereafter the first transgastric appendectomy was performed in humans.^11,12 The technique has further been adopted in cholecystectomy, appendectomy, gastrectomy, and nephrectomy procedures.¹³ 

Given rapid interest in a possible paradigm shift in the field of minimally invasive surgery, the Natural Orifice Surgery Consortiumfor Assessment and Research (NOSCAR) was formed, and the group published an article on potential barriers to accepted practice and adoption of NOTES as a realistic alternative to traditional laparoscopic surgery.¹⁴ 

While transgastric and transanal access to the peritoneum were initially more popular, the risk of anastomotic leaks associated with incomplete closure and subsequent infection were thought to be prohibitively high.¹⁵ Transvaginal access was considered a safer and simpler alternative, allowing for complete closure without increased risk of infection, and this is now the route through which the majority of NOTES procedures are completed.^16,17 

The eventual application of NOTES in the field of gynecology seemed inevitable. The American College of Obstetricians and Gynecologists stated that transvaginal surgery is the most minimally invasive and preferred surgical route in the management of patients with benign gynecologic diseases.¹⁸ However, performing it can be challenging at times due to limited visualization and lack of the required skills for single-site surgery. NOTES allows a gynecologic surgeon to improve visualization through the use of laparoendoscopic instruments and to complete surgery through a transvaginal route. 

In 2012, Ahn and colleagues demonstrated the feasibility of the NOTES technique in gynecologic surgery after using it to successfully complete benign adnexal surgery in 10 patients.¹⁹ Vaginal NOTES (vNOTES) has since been further developed to include successful hysterectomy, myomectomy, sacrocolpopexy, tubal anastomosis, and even lymphadenectomy in the treatment of early- stage endometrial carcinoma.^20-26 vNOTES also can be considered a rescue approach for traditional vaginal hysterectomy in instances in which it is necessary to evaluate adnexal pathology.⁹ Most recently, vNOTES hysterectomy has been reported with da Vinci Si or Xi robotic platforms.^27,28 

Continue to: Operative time, post-op stay shorter in NAOC-treated patients...

Few studies have compared outcomes with vNOTES to those with traditional laparoscopy. In 2016, Wang and colleagues compared surgical outcomes between NOTES-assisted ovarian cystectomy (NAOC) and laparoscopic ovarian cystectomy (LOC) in a case-matched study that included 277 patients.²⁹ Although mean (SD) blood loss in patients who underwent LOC was significantly less compared with those who underwent NAOC (21.4 [14.7] mL vs 31.6 [24.1] mL; P = .028), absolute blood loss in both groups was deemed minimal. Additionally, mean (SD) operative time and postoperative stay were significantly less in patients undergoing NAOC compared with those having LOC (38.23 [10.19] minutes vs 53.82 [18.61] minutes; P≤.001; and 1.38 [0.55] days vs 1.82 [0.52] days; P≤.001; respectively).²⁹ 

How vNOTES hysterectomy stacked up against TLH 

In 2018, Baekelandt and colleagues compared outcomes between vNOTES hysterectomy and total laparoscopic hysterectomy (TLH) in a noninferiority single-blinded trial of 70 women.⁸ Compared with TLH, vNOTES hysterectomy was associated with shorter operative time (41 vs 75 minutes; P<.001), shorter hospital stay (0.8 vs 1.3 days; P = .004), and lower postoperative analgesic requirement (8 vs 14 U; P = .006). Additionally, there were no differences between the 2 groups in postoperative infection rate, intraoperative complications, or hospital readmissions within 6 weeks.⁸

Approach for performing vNOTES procedures 

At our institution, Baylor College of Medicine, the majority of gynecologic surgeries are performed via either transumbilical robot-assisted single-incision laparoscopy or vNOTES. Preoperative selection of appropriate candidates for vNOTES includes: 

• low suspicion for or prior diagnosis of endometriosis with obliteration of the posterior cul-de-sac 
• no surgical history suggestive of severe adhesive disease, and 
• adequate vaginal sidewall access and sufficient descent for instrumentation for entry into the peritoneal cavity. 

In general, a key concept in vNOTES is "vaginal pull, laparoscopic push," which means that the surgeon must pull the cervix while performing vaginal entry and then push the uterus back in the peritoneal cavity to increase surgical space during laparoscopic surgery. 

Continue to: Overview of vNOTES steps...

Below we break down a description of vNOTES in 6 sections. Our patients are always placed in dorsal lithotomy position with TrenGuard (D.A. Surgical) Trendelenburg restraint. We prep the abdomen in case we need to convert to transabdominal surgery via transumbilical single-incision laparoscopic surgery or traditional laparoscopic surgery. 

1. Vaginal entry 

Accessing the peritoneal cavity through the vagina initially proceeds like a vaginal hysterectomy. We inject dilute vasopressin (20 U in 20 mL of normal saline) circumferentially in the cervix (for hysterectomy) or in the posterior cervix in the cervicovaginal junction (for adnexal surgery without hysterectomy) for vasoconstriction and hydrodissection. 

We then incise the vaginal mucosa circumferentially with electrosurgical cautery and follow with posterior colpotomy. We find that reapproximating the posterior peritoneum to the posterior vagina with either figure-of-8 stitches or a running stitch of polyglactin 910 suture (2-0 Vicryl) assists in port placement, bleeding at the peritoneal edge, and closure of the cuff or colpotomy at the end of the case. We tag this suture with a curved hemostat. 

Depending on whether a hysterectomy is being performed, anterior colpotomy is made. Again, the anterior peritoneum is then tagged to the anterior vaginal cuff in similar fashion, and this suture is tagged with a different instrument; we typically use a straight hemostat or Sarot clamp (FIGURE 1). 

2. Traditional vaginal hysterectomy 

After colpotomy, we prefer to perform progressive clamping of the broad ligament from the uterosacral and cardinal ligaments to the level of uterine artery as in traditional vaginal hysterectomy, if feasible. 

3. Single-site port placement 

The assembled GelPOINT Mini advanced access platform (Applied Medical) (FIGURE 2) is introduced through the vagina after the Alexis wound protector (included with the kit) is first placed through the colpotomy with assistance of Babcock clamps (FIGURE 3). 

After ensuring that the green rigid ring of the Alexis wound protector is contained and completely expanded within the peritoneal cavity, we cross our previously tagged sutures as we find this helps with preventing the GelPOINT Mini access platform from inadvertently shifting out of the peritoneal cavity during surgery. The GelSeal cap is then secured and pneumoperitoneum is established (FIGURE 4). 

Continue to: 4. Laparoendoscopic surgery...

Instruments used in our surgeries include a 10-mm rigid 30° 43-cm working length laparoscope; a 44-cm LigaSure device (Medtronic); a 5-mm, 37-cm laparoscopic cobra grasping forceps and fenestrated grasper (Karl Storz); and a 5-mm, 45-cm laparoscopic suction with hydrodissection tip (Stryker) (FIGURE 5). 

vNOTES allows a gynecologic surgeon the unique ability to survey the upper abdomen. The remainder of the surgery proceeds using basic laparoscopic single-site skills. 

During vNOTES, as with all single-site surgical procedures, understanding the optimal placement of crossed instruments is important for successful completion. For example, when securing the right uterine artery, the surgeon needs to push the cervix toward the patient's left and slightly into the peritoneal cavity using a laparoscopic cobra grasper with his or her left hand while then securing the uterine pedicle using the LigaSure device with his or her right hand. This is then reversed when securing the left uterine artery, where the assistant surgeon pushes the cervix toward the patient's right while the surgeon secures the pedicle ("vaginal pull, laparoscopic push") (FIGURE 6). 

This again is reiterated in securing the ovarian pedicles, which are pushed into the peritoneal cavity while being secured with the LigaSure device. 

5. Specimen removal 

For large uteri or specimens that need morcellation, a 15-mm Endo Catch specimen retrieval bag (Medtronic) is introduced through the GelPOINT Mini system. The specimen is then placed in the bag and delivered to the vagina, where contained bag morcellation is performed in standard fashion (FIGURES 7 AND 8). We utilized the "big C" technique by first grasping the specimen with a penetrating clamp. The clamp is then held in our nondominant hand and a No. 10 blade scalpel is used to create a reverse c-incision, keeping one surface of the specimen intact. This is continued until the specimen can be completely delivered through the vagina. 

Specimens that do not require morcellation can be grasped laparoscopically, brought to the GelPOINT Mini port, which is quickly disassembled, and delivered. The GelSeal cap is then reassembled. 

6. Vaginal cuff closure 

The colpotomy or vaginal cuff is closed with barbed suture continuously, as in traditional vaginal hysterectomy cuff closure. Uterosacral ligament suspension should be performed for vaginal cuff support.  
 

Through the years, the surgical approach to hysterectomy has expanded from its early beginnings of being performed only through an abdominal or transvaginal route with traditional surgical clamps and suture. The late 1980s saw the advent of the laparoscopic-assisted vaginal hysterectomy (LAVH), and from that point forward several additional hysterectomy methods evolved, including today’s robotic approaches.

Although clinical evidence and societal endorsements support vaginal hysterectomy as a superior high-value modality, it remains one of the least performed among all available routes.^1-3 In an analysis of inpatient hysterectomies published by Wright and colleagues in 2013, 16.7% of hysterectomies were performed vaginally, a number that essentially has remained steady throughout the ensuing years.⁴

Attempts to improve the application of vaginal hysterectomy have been made.⁵ These include the development of various curriculum and simulation-based medical education programs on vaginal surgical skills training and acquisition in the hopes of improving utilization.⁶ An interesting recent development is the rethinking of vaginal hysterectomy by several surgeons globally who are applying facets of the various hysterectomy methods to a transvaginal approach known as vaginal natural orifice transluminal endoscopic surgery (vNOTES).^7,8 Unique to this thinking is the incorporation of conventional laparoscopic instrumentation.

Although I have not yet incorporated this approach in my surgical armamentarium at Columbia University Medical Center/New York–Presbyterian Hospital, I am intrigued by the possibility that this technique may serve as a rescue for vaginal hysterectomies that are at risk of conversion or of not being performed at all.⁹

At this time, vNOTES is not a standard of care and should be performed only by highly specialized surgeons. However, in the spirit of this Update on minimally invasive surgery and to keep our readers abreast of burgeoning techniques, I am delighted to bring you this overview by Dr. Xiaoming Guan, one of the pioneers of this surgical approach, and Dr. Tamisa Koythong and Dr. Juan Liu. I hope you find this recent development in hysterectomy of interest.

—Arnold P. Advincula, MD

Continue to: Development and evolution of NOTES...

Development and evolution of NOTES 

Over the past few decades, emphasis has shifted from laparotomy to minimally invasive surgery because of its proven significant advantages in patient care, such as improved cosmesis, shorter hospital stay, shorter postoperative recovery, and decreased postoperative pain and blood loss.¹⁰  Advances in laparoendoscopic surgery and instrumentation, including robot-assisted laparoscopy (RAL), single-incision laparoscopic surgery (SILS), and most recently natural orifice transluminal endoscopic surgery (NOTES), reflect ongoing innovative developments in the field of minimally invasive surgery. 

Here, we provide a brief literature review of the NOTES technique, focus on its application in gynecologic surgery, and describe how we perform NOTES at our institution. 

NOTES application in gynecology 

With NOTES, peritoneal access is gained through a natural orifice (such as the mouth, vagina, urethra, or anus) to perform endoscopic surgery, occasionally without requiring an abdominal incision. First described in 2004, transgastric peritoneoscopy was performed in a porcine model, and shortly thereafter the first transgastric appendectomy was performed in humans.^11,12 The technique has further been adopted in cholecystectomy, appendectomy, gastrectomy, and nephrectomy procedures.¹³ 

Given rapid interest in a possible paradigm shift in the field of minimally invasive surgery, the Natural Orifice Surgery Consortiumfor Assessment and Research (NOSCAR) was formed, and the group published an article on potential barriers to accepted practice and adoption of NOTES as a realistic alternative to traditional laparoscopic surgery.¹⁴ 

While transgastric and transanal access to the peritoneum were initially more popular, the risk of anastomotic leaks associated with incomplete closure and subsequent infection were thought to be prohibitively high.¹⁵ Transvaginal access was considered a safer and simpler alternative, allowing for complete closure without increased risk of infection, and this is now the route through which the majority of NOTES procedures are completed.^16,17 

The eventual application of NOTES in the field of gynecology seemed inevitable. The American College of Obstetricians and Gynecologists stated that transvaginal surgery is the most minimally invasive and preferred surgical route in the management of patients with benign gynecologic diseases.¹⁸ However, performing it can be challenging at times due to limited visualization and lack of the required skills for single-site surgery. NOTES allows a gynecologic surgeon to improve visualization through the use of laparoendoscopic instruments and to complete surgery through a transvaginal route. 

In 2012, Ahn and colleagues demonstrated the feasibility of the NOTES technique in gynecologic surgery after using it to successfully complete benign adnexal surgery in 10 patients.¹⁹ Vaginal NOTES (vNOTES) has since been further developed to include successful hysterectomy, myomectomy, sacrocolpopexy, tubal anastomosis, and even lymphadenectomy in the treatment of early- stage endometrial carcinoma.^20-26 vNOTES also can be considered a rescue approach for traditional vaginal hysterectomy in instances in which it is necessary to evaluate adnexal pathology.⁹ Most recently, vNOTES hysterectomy has been reported with da Vinci Si or Xi robotic platforms.^27,28 

Continue to: Operative time, post-op stay shorter in NAOC-treated patients...

Few studies have compared outcomes with vNOTES to those with traditional laparoscopy. In 2016, Wang and colleagues compared surgical outcomes between NOTES-assisted ovarian cystectomy (NAOC) and laparoscopic ovarian cystectomy (LOC) in a case-matched study that included 277 patients.²⁹ Although mean (SD) blood loss in patients who underwent LOC was significantly less compared with those who underwent NAOC (21.4 [14.7] mL vs 31.6 [24.1] mL; P = .028), absolute blood loss in both groups was deemed minimal. Additionally, mean (SD) operative time and postoperative stay were significantly less in patients undergoing NAOC compared with those having LOC (38.23 [10.19] minutes vs 53.82 [18.61] minutes; P≤.001; and 1.38 [0.55] days vs 1.82 [0.52] days; P≤.001; respectively).²⁹ 

How vNOTES hysterectomy stacked up against TLH 

In 2018, Baekelandt and colleagues compared outcomes between vNOTES hysterectomy and total laparoscopic hysterectomy (TLH) in a noninferiority single-blinded trial of 70 women.⁸ Compared with TLH, vNOTES hysterectomy was associated with shorter operative time (41 vs 75 minutes; P<.001), shorter hospital stay (0.8 vs 1.3 days; P = .004), and lower postoperative analgesic requirement (8 vs 14 U; P = .006). Additionally, there were no differences between the 2 groups in postoperative infection rate, intraoperative complications, or hospital readmissions within 6 weeks.⁸

Approach for performing vNOTES procedures 

At our institution, Baylor College of Medicine, the majority of gynecologic surgeries are performed via either transumbilical robot-assisted single-incision laparoscopy or vNOTES. Preoperative selection of appropriate candidates for vNOTES includes: 

• low suspicion for or prior diagnosis of endometriosis with obliteration of the posterior cul-de-sac 
• no surgical history suggestive of severe adhesive disease, and 
• adequate vaginal sidewall access and sufficient descent for instrumentation for entry into the peritoneal cavity. 

In general, a key concept in vNOTES is "vaginal pull, laparoscopic push," which means that the surgeon must pull the cervix while performing vaginal entry and then push the uterus back in the peritoneal cavity to increase surgical space during laparoscopic surgery. 

Continue to: Overview of vNOTES steps...

Below we break down a description of vNOTES in 6 sections. Our patients are always placed in dorsal lithotomy position with TrenGuard (D.A. Surgical) Trendelenburg restraint. We prep the abdomen in case we need to convert to transabdominal surgery via transumbilical single-incision laparoscopic surgery or traditional laparoscopic surgery. 

1. Vaginal entry 

Accessing the peritoneal cavity through the vagina initially proceeds like a vaginal hysterectomy. We inject dilute vasopressin (20 U in 20 mL of normal saline) circumferentially in the cervix (for hysterectomy) or in the posterior cervix in the cervicovaginal junction (for adnexal surgery without hysterectomy) for vasoconstriction and hydrodissection. 

We then incise the vaginal mucosa circumferentially with electrosurgical cautery and follow with posterior colpotomy. We find that reapproximating the posterior peritoneum to the posterior vagina with either figure-of-8 stitches or a running stitch of polyglactin 910 suture (2-0 Vicryl) assists in port placement, bleeding at the peritoneal edge, and closure of the cuff or colpotomy at the end of the case. We tag this suture with a curved hemostat. 

Depending on whether a hysterectomy is being performed, anterior colpotomy is made. Again, the anterior peritoneum is then tagged to the anterior vaginal cuff in similar fashion, and this suture is tagged with a different instrument; we typically use a straight hemostat or Sarot clamp (FIGURE 1). 

2. Traditional vaginal hysterectomy 

After colpotomy, we prefer to perform progressive clamping of the broad ligament from the uterosacral and cardinal ligaments to the level of uterine artery as in traditional vaginal hysterectomy, if feasible. 

3. Single-site port placement 

The assembled GelPOINT Mini advanced access platform (Applied Medical) (FIGURE 2) is introduced through the vagina after the Alexis wound protector (included with the kit) is first placed through the colpotomy with assistance of Babcock clamps (FIGURE 3). 

After ensuring that the green rigid ring of the Alexis wound protector is contained and completely expanded within the peritoneal cavity, we cross our previously tagged sutures as we find this helps with preventing the GelPOINT Mini access platform from inadvertently shifting out of the peritoneal cavity during surgery. The GelSeal cap is then secured and pneumoperitoneum is established (FIGURE 4). 

Continue to: 4. Laparoendoscopic surgery...

Instruments used in our surgeries include a 10-mm rigid 30° 43-cm working length laparoscope; a 44-cm LigaSure device (Medtronic); a 5-mm, 37-cm laparoscopic cobra grasping forceps and fenestrated grasper (Karl Storz); and a 5-mm, 45-cm laparoscopic suction with hydrodissection tip (Stryker) (FIGURE 5). 

vNOTES allows a gynecologic surgeon the unique ability to survey the upper abdomen. The remainder of the surgery proceeds using basic laparoscopic single-site skills. 

During vNOTES, as with all single-site surgical procedures, understanding the optimal placement of crossed instruments is important for successful completion. For example, when securing the right uterine artery, the surgeon needs to push the cervix toward the patient's left and slightly into the peritoneal cavity using a laparoscopic cobra grasper with his or her left hand while then securing the uterine pedicle using the LigaSure device with his or her right hand. This is then reversed when securing the left uterine artery, where the assistant surgeon pushes the cervix toward the patient's right while the surgeon secures the pedicle ("vaginal pull, laparoscopic push") (FIGURE 6). 

This again is reiterated in securing the ovarian pedicles, which are pushed into the peritoneal cavity while being secured with the LigaSure device. 

5. Specimen removal 

For large uteri or specimens that need morcellation, a 15-mm Endo Catch specimen retrieval bag (Medtronic) is introduced through the GelPOINT Mini system. The specimen is then placed in the bag and delivered to the vagina, where contained bag morcellation is performed in standard fashion (FIGURES 7 AND 8). We utilized the "big C" technique by first grasping the specimen with a penetrating clamp. The clamp is then held in our nondominant hand and a No. 10 blade scalpel is used to create a reverse c-incision, keeping one surface of the specimen intact. This is continued until the specimen can be completely delivered through the vagina. 

Specimens that do not require morcellation can be grasped laparoscopically, brought to the GelPOINT Mini port, which is quickly disassembled, and delivered. The GelSeal cap is then reassembled. 

6. Vaginal cuff closure 

The colpotomy or vaginal cuff is closed with barbed suture continuously, as in traditional vaginal hysterectomy cuff closure. Uterosacral ligament suspension should be performed for vaginal cuff support.