The state of gynecologic robotic surgery

November 9, 2020
Jon I. Einarsson, MD, PhD, MPH
Jon I. Einarsson, MD, PhD, MPH
Jon I. Einarsson, MD, PhD, MPH

Deputy Editor of Contemporary OB/GYN, Director of the Division of Minimally Invasive Gynecologic Surgery at Brigham and Women’s Hospital in Boston and professor of Obstetrics, Gynecology and Reproductive Biology at Harvard Medical School.

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Gaby Moawad, MD
Gaby Moawad, MD

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Robert K. Zurawin, MD
Robert K. Zurawin, MD

Technology Spotlight

Volume 65, Issue 11

Three esteemed surgeons discuss technology, weighing the pros and cons of existing and newly developed platforms.

Contemporary OB/GYN® Deputy Editor Jon I. Einarsson, MD, MPH, PhD, moderated a discussion with Robert K. Zurawin, MD, adjunct associate professor at the Baylor College of Medicine, Department of OB/GYN; and Gaby Moawad, MD, clinical associate professor of ob/gyn at the George Washington University School of Medicine and Health Sciences, and founder of the Center for Endometriosis and Advanced Pelvic Surgery.

The full video interview is available here.

In this article, adapted from the video interview, the surgeons discuss the current state of robotic surgery; the current robotic options available; and how new technology can be factored into clinical practice, the focus of which is the Hominis surgical system.

The Hominis is a transvaginal robotic-assisted system that has combined the visual advantages of laparoscopy with the transvaginal approach. It is said to enhance and enable transvaginal approaches. Its humanoid design includes two flexible, snake-like arms that mimic the movement and mobility of human arms.

Much of what the surgeons discuss is moving the needle on how hysterectomies are performed, since the vaginal approach remains the preferred method in the specialty, but is performed at a lower rate due to myriad factors. Abdominal hysterectomy is the most widely used approach. The Hominis is not yet for sale in the U.S. and pending FDA approval. Experts will present on it at the American Association of Gynecologic Laparoscopists Virtual Conference, being held Nov. 6-14.

“Technologies are coming through that will facilitate the ability of those with general knowledge of surgery to approach surgery safer and more cost-effectively, and make it more accessible to them to do these kinds of procedures,” Dr. Zurawin says.

The surgeons see the landscape for surgical technology constantly evolving, but that doesn’t replace the need for highly skilled surgeons. Patient outcomes remain the most critical goal. Artificial intelligence and machine learning could help modern medicine create algorithms to better understand triaging patients to different modalities of surgery, whether vaginal or laparoscopic.

“At the end of the day, it is the surgeon’s skill that is the most important factor and we often forget that,” Dr. Einarsson says. “That is the most important ingredient. New devices that are coming out are facilitating the existing surgeon’s skills and help surgeons to develop those skills.

“We do not need to glorify another robot,” he says. “We need to improve the innovative aspect of how the robot or how the computer-assisted surgery can help the surgeon standardizing the outcome of the surgery, rather than relying on a human to make decisions.”

The discussion begins with Dr. Zurawin, who provides background.

DR. ZURAWIN: You wanted to address the vaginal approach and this really speaks to the greatest unmet need of gyn surgeries because every single gynecological organization recommends vaginal hysterectomy as the preferred method of hysterectomy. But the needle hasn’t moved past 15 or 16%, forever.

The reason for that is anatomy, surgical training, and discomfort with surgeons who are coming through training - and even existing surgeons - who perform vaginal surgeries. The key to vaginal hysterectomy rests in safe dissection into the anterior/posterior cul-de-sacs, a feeling of security with securing the vessels, as well as avoiding the bladder and the rectum.

That is not only unchanged, but it has actually gotten worse, because the world of vaginal surgery now is out of the hand of the generalists and has moved to urogynecologists and some of the oncologists, and of course, specifically trained minimally invasive surgeons (MIGS-fellowship trained surgeons). So how can you possibly have vaginal hysterectomy as the preferred method of hysterectomy? Practically nobody knows how to do it. And one of the challenges is anatomy, but if you remember, back when many of us were in training, cesarean section was only a small percentage of deliveries and now it’s anywhere from 30 to 50 to 70 percent, depending on where you are.

Once you perform a c-section, you have an increased risk of scarring in the anterior cul-de-sac, so in addition to just getting cleanly into the anterior cul-de-sac, now you have got to dig through that scar tissue. A number of publications have shown the feasibility of vaginal hysterectomy after a cesarean but it still is keeping most people away. The vaginal robot creates an opportunity to combine robotic surgery with a laparoscopic view and a vaginal single-incision approach. One of the advantages of that is that the entry is guided by a small umbilical laparoscopic scope.

Then it monitors the entry of the trocar through the posterior cul-de-sac. You are not going to hit anything. It is direct visualization and then once the trocar is in, the robot arms are inserted and then retroflex. You can perform the hysterectomy and also adnexal surgery, and then remove the specimen through the colpotomy you made for the insertion of the trocar. The transvaginal robotic approach facilitates all those steps.

Other robotic platforms have attempted vaginal surgery but they run into problems of entry. There are a lot of excellent surgeons doing vNotes (transvaginal natural orifice transluminal endoscopic surgery), which of course is a very nice modality, but again, you have to get into the anterior and posterior cul-de-sac, before you even get to put in the GelPoint. By that point, 90% of the work is done. After that, you might just as well put a couple of clamps on the uterine vessels and you’re done. I just wanted to give a little background on the vaginal approach. Of course Hominis still is awaiting FDA approval but it is at the final stages.

Dr. Moawad has done a lot of tremendous work not only on the cost but training; Dr. Zurawin turns the discussion over to him.

DR. MOAWAD: These are all really great points that you brought in. We can start seeing why the value of robotic surgery would be beneficial in moving the needle towards vNotes or robotic vNotes.

In addition to what you said, the important thing is that the robotic platform is enabling the surgeon to be in control of the visualization as well as all the operative arms, minimizing the use of multiple assistants.

That always was a struggle when we did vaginal hysterectomies, where we have the learners, the surgeon and the assistant, all not being able to visualize clearly the important structures, like the ureters in vaginal hysterectomy, or other anatomical landmarks.

That was, I believe, one of the drawbacks of vaginal surgery, especially when we get into more complex and difficult cases. The type of pelvis, the body mass index of the patient, and then the more complexity of benign gynecological surgeries (including endometriosis) all lead to increasing the challenges in the vaginal approach.

The problem with endometriosis is that there are numerous surgeons who are not able to diagnose an obliterated cul-de-sac or having the tools to diagnose that before the surgery.

Therefore, many rectovaginal endometriosis [cases] with the general ob/gyn are diagnosed by accident intraoperatively. Imagine now with trying to push vNotes or vaginal surgery to a wide variety of less experienced surgeons, thinking that this is the primary approach without appropriate training and triaging of patients, this will lead to multiple safety issues that can compromise the outcomes.

Here I am going to play the devil’s advocate a little bit and open the discussion a little more, which is knowing that now most of the surgeries are done laparoscopically or robotically, or minimally invasive, let’s say, what could vNotes add to this safe laparoscopic surgery, especially now that we’re moving to less ports, more micro-ports, to minimize the injury or the trauma to the abdominal wall cavity?

DR. EINARSSON: From my perspective, and this is obviously my biased perspective, I like to see what I am doing. I remember in residency when I graduated, I did my residency with Dr. Zurawin, actually, and we did a lot of vaginal hysterectomies at that time. I think I graduated probably with 50 or 60 of them and I felt very comfortable.

When I got out I felt very strongly that I should be able to do all of these things and offer all of these modalities to my patients but then gradually just realized that there wasn’t any point because, if you think about the patient outcomes, whether you do it laparoscopically or vaginally, the patient outcomes are very similar but you can tackle anything laparoscopically, as opposed to vaginally, you kind of have to select patients a little bit more so I gradually moved to 100 percent laparoscopic.

Especially if you’re dealing with more challenging pathology, I think you need to be able to see. I think that adds so much to what you are dealing with. You can deal with endometriosis, complicated cysts, adhesions, much better than vaginally. vNotes has been interesting technology because it does combine the vaginal surgery and being able to see. I think that is probably the key to allow more people to use that access port.

DR. ZURAWIN: Those points come together this way; first of all, full disclosure, Dr. Einarsson doesn’t do robotic surgery because he can do anything laparoscopically. He doesn’t need anything else because he has a brilliant understanding of anatomy and decades of experience with thousands upon thousands of cases.

But for the purposes of this article, we are talking about the majority of gynecologists who don’t have those skills. Residents who finish now only have to do 15 vaginal hysterectomies to graduate, and they have a hard time scraping together even that number. They graduate without the skill or the confidence to perform vaginal surgery once they enter practice.

The difficulty there really comes back to knowledge of anatomy. In terms of visualization, Dr. Moawad brings up a great point about obliterated cul-de-sac. Many people recommend a diagnostic laparotomy before a lot of this is done to know what you’re getting into before you get into it. Now here is the controversy: if you’re doing a vaginal surgery, why are you popping a laparoscope in there? But let’s talk about that. In 1991, Stovall and Ling1 published their very excellent paper on 91 patients who were scheduled for vaginal hysterectomy.

Only a few of them were thought to be candidates, but when they popped in the umbilical scope, fully 90% of them were able to be done vaginally because the surgeons had the confidence of knowing the anatomy. That is really the elephant in the room here.

Unless people are properly trained, it doesn’t matter what modality you use, you are not going to be unable to do it. Unlike the other unfortunate circumstances we had with vaginal mesh, and all these other procedures where doctors were trained in weekend warrior sessions where they would claim to teach you how to do it, this is not something that you can just grab onto.

Another thing is the definition of a high-volume surgeon that is in the literature. A high-volume surgeon is what, 10, 12, major cases a year? You know, one a month? I mean I wouldn’t get on an airplane with a pilot that only flew once a month. I think what we are talking about is funneling these modalities into competent hands and yet facilitating the rest of the gynecologists who want to improve their vaginal surgery skills. I think vNotes is great; I think robotics is great; and I think laparoscopic surgery is great, but it needs to go into the right hands and that is the key.

Now the next thing about that is the expenses, the cost versus the benefit, and again, I am not nearly as conversant in that as Dr. Moawad is, so maybe he can help us out with that.

DR. MOAWAD: I’m going to talk about a very important aspect of robotic surgery, how it could help spread the robotic vNotes. And then when we look and learn from the experience about what robotic surgery did to open surgery, or laparotomy.

When we talk about hysterectomy, robotic surgery was able to shift most of the laparotomy into minimally invasive where a laparoscopy was steady and this was shown clearly in a lot of the graphs that we have in one of our studies, which was published in Plos One about the movement to outpatient hysterectomy in benign indications (in the United States, 2008-2014).2

We can see that laparoscopic surgery rates were mostly stable from 2008 to almost 2016 in terms of percentage. Robotic surgery, where we thought before it could take away from the laparoscopic surgery pool, ended up shifting the more complex procedures done [via] laparotomy to a minimally invasive option. If we extrapolate those graphs, that might be the actual benefit [of] what robotic surgery could do to the vNotes, where it could shift a lot of the laparoscopic, transabdominal, or robotic transabdominal, into a vNote modality but eventually, it is going to take a lot of learning.

Now in terms of cost, again, as most of the costs in the U.S., where we are talking the direct costs, comes from two things: The direct cost comes from the operative time length; and redundancy of using multiple instruments that have the same function. The third factor, which we never talk about, is the cost of complications, re-admissions, conversions, re-operations. This is what drives the major costs in the U.S. for surgery.

It might not be true for other countries but this is the main cost factor here. The more efficient surgeon using the appropriate tools with the right training is what will help drive the costs down.

We need to consider as well the opportunity costs, which is whatever the hospital can do with those resources that were not used if the patient was not admitted to the hospital; rather, what if the patient was discharged the same day with a minimally invasive surgery option? This is the total cost that we need to look at mainly.

Next, Dr. Zurawin elaborates on Dr. Moawad’s points about complications.

DR. ZURAWIN: This brings us to my concern about anatomy and patient volume. The issue that needs to be addressed, with any new technology, from endometrial ablation to hysteroscopic sterilization, mesh - anything that we were doing -it’s not the device itself, it’s the surgeon. In terms of post-operative complications with robotics, I think all three of us see medical-legal cases that are related to robotic surgery and most of them that I see are thermal injury.

They mostly involve burning the bladder, a burning of the bowel, or of the ureter. I think that visualization is important, of course, but unless we properly train our surgeons, unless we change our training programs, we’re really going to see an acceleration of this problem.

That is why, when we adopt these technologies, we need to put them in the hands of the people who can do it. In terms of Dr. Moawad’s point about robotic vNotes, I think that is an excellent future for the specialty. It takes all the advantages of the vaginal approach, all of the technical and engineering aspects of robotics, as well as cost and recovery.

Again, I just feel strongly, at least in the beginning, these technologies have to be directed or restricted to people who really, really know what they are doing.

One of my other fellows introduced vNotes and robotic vNotes into China where it has really caught on very big but it is a different market there and it’s a different group of surgeons. Gynecologists in China do thousands of cases, many thousands of cases. We don’t have that here in the USA.

DR. EINARSSON: If you think about what is most important, obviously that is patient outcomes, and what is the most important thing there, I agree with you, that it probably is the surgeon’s volume. It’s not which robot they’re using or whether they are doing laparoscopic or vaginal surgery. Of course, that should be the main focus.

My view on that is actually a little bit more optimistic because I think that more and more cases, especially in urban areas, are going to high-volume providers. We’ve been graduating now a few hundred fellows in laparoscopic surgery or minimally invasive gynecologic surgery, and they’re gradually building their practices and taking more cases.

If you’re an ob/gyn specialist and coming out of school, then your surgical volume is so low and it’s very hard for you to get up to speed on that. It is almost untenable in larger urban areas because high-volume surgeons are doing much more cases, and I think that translates to better outcomes for patients, which obviously is what we want. I think that is happening, at least in urban areas. In smaller communities, it is not as clear cut.

The debate still is ongoing in the specialty that robotics surgery is less expensive, and there are those who will say it is more expensive. What is the surgeons’ take? As Dr. Zurawin asks, “What is the real news about costs of robotic surgery, if you consider all factors, with costs and morbidity, costs to the hospital and to the insurance system?”

DR. MOAWAD: This is always going to be a question of which comes first – the chicken or the egg? Because it’s the same debate and let me tell you why. All the published studies in the literature have a major bias, which is that we don’t compare apples to apples and oranges to oranges.

The whole issue arises because we don’t have a complexity score for hysterectomy. What we use as a proxy for complexity is the weight of the uterus, which we all know is nonsense.

The challenge with robotic surgery is that we do not have a way to separate the learning curve of different surgeons.

But it is not only the learning curve, because many people are lured that they will become expert surgeons if they do 20 robotic cases and this is probably some of the marketing pitfalls to engage people. But the proficiency curve, which is around 100 cases, and 100 cases to be met for surgeons who are even considered high volume doing 15, or 20, or 30 a year, that is going to take them 3 or 4 years to get to that level.

The major issues we have are defining the complexity of a hysterectomy and assessing the surgeon’s skills and then we can compare groups using the same metrics.

When it comes to costs, you have papers like Dr. Luciano’s: “The impact of robotics on the mode of benign hysterectomy and clinical outcomes,”3 where he studied the premier database and found the complication rate with robotic surgery, despite obesity, is lower than laparoscopic and open surgery.

But you have other studies such as Paraiso,4 the sacrocolpopexy randomized trial, again, such studies show that robots are more expensive and require longer time and that is why it will be more costly. But in most of the studies there was no difference between the complications between laparoscopy and robotics. Having a laparoscopic surgeon spending four hours in the OR where the costs of an OR minute in the U.S. is $85, is very different than having a robotic surgeon doing the same surgery in one hour. It is going to be way less expensive.

Therefore it is surgeon-dependent if you have a laparoscopic surgeon admitting the patient overnight just because this is the practice, where a post-anesthesia-care-unit minute costs $15 versus a robotic surgeon sending a patient home after three hours.

That is going to be a major difference in cost. So there are practice-dependent cost incurrences; surgeon-skill-dependent cost incurrences, and as you said before, the right tool is the right hand to lead to the best outcomes not only financial-wise but also medical wise.

As BMI increases in the U.S. population, the surgeons also considered how modalities should be considered when working with morbidly obese patients.

DR. ZURAWIN: A transvaginal approach has definite advantages in morbidly obese patients. You don’t need the steep Trendelenburg necessarily that you do for robotics.

I’d be interested to know your experience, Dr. Moawad, and also Dr. Einarsson, you deal with a lot of morbidly obese patients and also in your training program. How do you see the people that you’re training dealing with the epidemic of obesity and its relation to modality – laparoscopic, robotic, and vaginal?

DR. EINARSSON: I want to first echo what Dr. Moawad was saying. I now have done a few randomized trials on robotic versus laparoscopic surgery and we’ve done some retrospective and cohort studies and all. Most of our studies are biased, I will admit that, because I am a much more proficient laparoscopic surgeon than a robotic surgeon.

I think that is probably true for most surgeons that they have their modality that they’re really, really good at and then the other stuff they’re not quite as good at. It’s hard to do randomized trials from surgical access because the bias always is on the surgeon.

Population-based studies or having groups that are really good at or in similar environments, and comparing those outcomes, are probably the least subject to bias but it’s never going to be really perfect.

In terms of obesity, I will offer a couple of things. The bigger the patient the more important patient positioning is but what I found helpful with laparoscopy over robotics in obese patients is that I can have complete freedom to move the patient the way I want at any time during surgery so I like to put the patient in a very steep Trendelenburg like 30 degrees, pull the bowel away, and then decrease the Trendelenburg, until the bowel starts to move down but it’s not in my way, and then stay in that position.

Then you can always put the patient down flat if anesthesia is having a problem then go back. Sometimes you do have to maneuver that around. I know that obviously there are those tables that move with the robot where you can move everything and you have the same freedom but not everybody has access to that. So that is one advantage.

But I know a lot of people like robotics for obese patients and have different reasons and maybe Dr. Moawad can elaborate on that.

DR. MOAWAD: With obesity, the advantage is that you do not have the fulcrum effect from the thickness of the abdominal wall as you do in laparoscopy. Many times, of course, for more experienced surgeons they can overcome this or overlook that but many times this is a challenge.

Plus, most of the laparoscopic instruments sometimes for extremely obese patients start becoming a challenge and we do use bariatric [instruments] because the [other instruments] don’t get to where you want to be.

With obesity, the precise movement with a laparoscope will become an issue when we are dealing with way more complex cases. In laparoscopy, many times, when you have a more complex case, you rely more on your assistant, in the sense that they have to do more, and be more actively engaged in the surgery rather than when doing a simple case.

You have to rely on the surgeons being ambidextrous for super complex cases, where, if the assistant cannot do the job on their side, the surgeon can move with the same efficiency with both hands. These are challenges mitigated by robotic surgery.

I think one of the values nobody talks about in robotic surgery is how your assistant becomes less and less relied upon throughout the procedure where you can have three arms and a camera that you fully control rather than, at most, two arms with laparoscopic surgery.

This is one of the values we go back to, the robotic vNotes, one of the values that robotic (has is that it) could help overcome the challenges of traditional vNotes laparoscopy. With obesity, you have even more limited range of motion with less precision.

Dr. Moawad asks Dr. Zurawin to provide his perspective on managing obese patients with the Hominis platform. Dr. Zurawin has been involved in the trials with the platform in Belgium.

DR. ZURAWIN: The largest hysterectomy we’ve done with Hominis is 15-week size, which is good enough, even with some adhesions. We have not done many morbidly obese patients because the trials were done in Europe and Israel where the population is generally thinner.

We also have not had to put them into steep Trendelenburg. Of course, vaginally, it’s a whole different world because of the way you position the patient, the bowel is normally out of the way, unless there are some adhesions that stick the bowel to the cul-de-sac.

We haven’t run into those problems but the question back at you is for the robotic vNotes, or any of your vNotes but especially robotic vNotes, don’t you also pop a scope into the umbilicus and look before you do your vNotes? Or are you just going to go in there, hoping that we don’t have a deep infiltrating endometriosis?

DR. MOAWAD: I don’t do vNotes but I think access to the abdominal cavity is going to be the main issue, in addition to the reverse anatomy that the surgeon now needs to be familiar with. When they did vaginal surgery they went by tactile feel; they didn’t go by look and then even for the laparoscopic surgeons, seeing anatomy in reverse is going to be also something that they need to be accustomed to.

They need to know the different views of the different landmarks. Because now as a laparoscopic surgeon when you look at the abdomen from open incision you start feeling the difference how much you’re more comfortable doing laparoscopy and finding the ureter than when you’re looking above into a laparotomy incision especially for challenging cases.

Nobody talks about the type of pelvis in pelvic surgery, and I think that is going to be one of the major determinants in the success of vNotes. Because if you have a platypelloid pelvis where the pubis bone is very close to the coccyx, then the range of motion of the straight stick instrument doing vNote is going to impact the difficulty of the cases. be way more challenging to do more complex cases.

If you have an android pelvis that is going to be a deeper pelvis that requires longer instruments to reach the surgical site, so there is a lot of learning. I think we go back to the same thing where we thought it should be done by expert surgeons before we can find a standardization of triage because triaging patients to vNote is going to be the main issue.

Using a standardized patient triage guidelines as an initial metric will be helpful to increase the success of that surgery and minimize the complication would be key.

DR. EINARSSON: Just to step up from that point, where do you see vNotes and Hominis robot enter clinical practice? Where are these going to be useful? VNotes is being used for sacrocolpopexies and ovarian cysts, etc. Where do you see this vaginal robotic access fit into clinical practice?

Studies on procedures other than vaginal hysterectomies have been conducted with the Hominis, including a bilateral salpingo oophorectomy.5 Other procedures have included treatment of ovarian cysts, adhesions, fibroids and prolapse.

DR. ZURAWIN: But cases like sacrocolpopexies – remember you’ve got a colpotomy – so just by that nature it makes it a little harder to do sacrocolpopexies with that Hominis robot because it goes in and it retroflexes 180 degrees. So that hasn’t really been tried yet. I think where its utility is going to be proven is cost.

It’s a small, portable, inexpensive robot for, at least at this point, cases that don’t need a bigger platform. In future iterations it will be used for other surgical devices, cases besides gynecology – head and neck surgery, and so on.

But in keeping to the gyn area, I think that it is going to find its niche in people who have had challenges in doing vaginal surgery and helping them enter into the world of vaginal surgery because entry into the peritoneal cavity is easy; dissection is easy; and it allows them to use a vaginal approach but with much better visualization. I think that is going to be where it starts.

Then when version 2.0 or 3.0 comes out there will be more indications. But I think it will encourage people to go back into that vaginal surgery as the preferred method of gynecologic surgery.

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References

  1. Summitt RL Jr, Stovall TG, Lipscomb GH, Ling FW. Randomized comparison of laparoscopy-assisted vaginal hysterectomy with standard vaginal hysterectomy in an outpatient setting. Obstet Gynecol. 1992 Dec;80(6):895-901. PMID: 1448255.
  2. Moawad G, Liu E, Song C, Fu AZ (2017) Movement to outpatient hysterectomy for benign indications in the United States, 2008–2014. PLoS ONE 12(11): e0188812. https://doi.org/10.1371/journal.pone.0188812
  3. Luciano, A. A., Seshadri-Kreaden, U., Gabbert, J., & Luciano, D. E. (march 2016). The impact of robotics on the mode of benign hysterectomy and clinical outcomes. The International Journal of Medical Robotics and Computer Assisted Surgery, 12(1), 114-124. doi:https://doi.org/10.1002/rcs.1648
  4. Paraiso MF, Jelovsek JE, Frick A, Chen CC, Barber MD. Laparoscopic compared with robotic sacrocolpopexy for vaginal prolapse: a randomized controlled trial. Obstet Gynecol. 2011 Nov;118(5):1005-13. doi: 10.1097/AOG.0b013e318231537c. PMID: 21979458.
  5. Lowenstein, L., Matanes, E., Weiner, Z., & Baekelandt, J. (July 2020). Robotic transvaginal natural orifice transluminal endoscopic surgery for bilateral salpingo oophorectomy. European Journal of Obstetrics & Gynecology and Reproductive Biology: X, 7, 100113. doi:10.1016/j.eurox.2020.100113
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