Single-Port Robotic Surgery for Prostate Cancer: An Interview With Mutahar Ahmed, MD

By Akhil Abraham Saji, MD - Last Updated: April 7, 2023

First approved in September 2018, single-port robotic surgery is now being used worldwide for various urologic surgeries.

I sat down with Mutahar Ahmed, MD, director of the Center for Bladder Cancer at Hackensack University Medical Center and one of the pioneers of single-port robotic surgery in the United States, to discuss the history and current applications of single-port robotic surgery in prostate cancer and beyond.

Could you tell us a little bit about your background and share your involvement in the history of single-port robotic surgery?

Dr. Ahmed: I finished my residency in 2003, and that was when robotic surgery was being introduced. When I was doing my residency, I was fortunate to rotate at Hackensack—one of the earliest hospitals to obtain the robotic platform. Like everyone else, we ventured into doing prostatectomy first, and then shortly thereafter started doing partial nephrectomies. The robot gave you that little bit of extra preciseness. You could do more precise suturing and dissection. That helped with the prostate; it is one of the most complex surgeries if you do it open. One of my attendings used to tell me that the prostate was not meant to be taken out. When I did open surgery with him in my residency, every time after the case he’d say, “the prostate is not meant to be taken out.” Surgeons started using laparoscopy (for prostate), but it was tiring. Once the robot came in and we started to master the skill required to use it, that made the prostatectomy a lot easier. You could have a debate about open versus robotics, but we know the robot has taken over prostatectomy in the United States. Now, almost 100% of prostate surgeries are being done robotically.

After mastering the prostatectomy, we ventured into partial nephrectomies and reconstruction. In 2006, I did my first robotic cystectomy, and that was the mother of urologic surgery. Initially, I was still doing the bowel work extracorporeally, but I quickly transitioned to doing it intracorporeally. Right now, I will hardly do anything open unless you have maybe a 20-centimeter kidney mass or a thrombus that goes well above the intrahepatic or above the diaphragm. Otherwise, we have pretty much converted everything into robotic, including all major oncologic surgery. I think mastering the anatomy is the key—if you do open surgery, robotic surgery, laparoscopic surgery, you must know your anatomy—at that point, after doing that anatomical work, the robot makes it easy. That’s my opinion, and I have probably done 5000 to 6000 robotic cases of various types. It allows us to do surgery in a more minimally invasive way while facilitating surgeons’ physical well-being, including eliminating back, shoulder, and neck issues.

Single-port (da Vinci SP) was released in 2018, but Intuitive was working on a single-port robot starting back in 2010. At first, they came in with single-site surgery, which was not single-port. It was multiple robotic arms going through 1 trocar, flexible, flimsy instruments. I tried it out, but the instrument strength was not good. It was very flexible. In general surgery, they were doing surgical procedures on the appendix and gallbladder, but even for those small cases they didn’t appreciate it. Intuitive knew they had to come up with something better, and in 2018 we received the true single-port platform.

In the past, people tried the single-incision laparoscopy by trying to do laparoscopic surgery through a natural orifice or the umbilicus and doing it through 1 incision. I tried it laparoscopically. There was a lot of collision, and angulation of instruments was not ideal. Patients had more pain at the incision site and increased rate of hernia. However, our quest for doing minimally invasive surgery even more minimally continued. In 2018, Intuitive finally got approved for the current single-port system. It’s relatively new, but Hackensack again was in the forefront, and we got our single-port robot in December 2018.

What did you think at first of this new technology?

Dr. Ahmed: I always like new technology. I got on it quickly. They had just brought it out with the metal trocar, and you have to have a certain clearance before the arm can angulate. You need about 10 to 12 inches. You could do transperitoneal surgery with that metal trocar, but you could not really do extraperitoneal surgery well. We realized that this was not going to work. That is where the concept of air docking came into view, and we started to play around with it. We realized that if we can’t change the focal point to outside the body using the metal trocar we would need another option, and so the idea of GelPoint trocar came in.

Once we got the idea about the air docking, we were able to change the focal point. If you are doing an extraperitoneal prostate, you don’t have that 10-inch clearance to work with. If you pull that trocar back, you are going to be outside the body. Likewise for retroperitoneal kidney surgery. The GelPoint allowed us to expand to extraperitoneal space.

When I first used the SP robot, I was basically reproducing my multiport surgery with the single-port. I started doing transperitoneal prostate with the single-port, adding a plus-one assistant port, but still going through transperitoneal. I was doing kidneys like that. I did some ureteropelvic junction repairs via a similar approach. Once the concept of air docking was possible using the GelPoint, I quickly moved to doing extraperitoneal prostate and retroperitoneal partial nephrectomy. Intuitive realized quickly from our feedback in regard to the GelPoint and air docking idea, and they came up with an SP robot access port called the globe. They added many features to it and allowed us to simplify steps. It has the port where the robot can be docked. There is an assistant port with the 12-millimeter, which you could use to place a bulldog or for a stapler device. There is also an additional side port, an 8-millimeter, where you could put an accessory like your flexible suction device after placing an 8-milimeter AirSeal trocar.

Single-port robot

Speaking of the flexible suction device, it is a must-have for SP robotic surgery (ROSI by VTI Technologies). It allows you to eliminate an assistant and gives you full control of the case.

The SP robot really changed my approach and worked out well for me because I was doing intraperitoneal surgery for prostate and kidney, and I was quickly able to move to an extraperitoneal approach. This allowed me to send most of my patients home on the same day and with less pain, a quicker recovery, and of course better cosmesis. Initially, when I started, I would do a patient with low BMI with a prostate of no more than 40 to 50 grams. But once I got comfortable, now I am able to do almost all types of cases.

What is the SPAM (SP Ahmed Modification) incision, how does it work? What has been your experience with it?

Dr. Ahmed: I started doing partial nephrectomy with the SP robot transperitoneally through a midline or a little lateral to the midline if the patient had a high BMI. But then I started to think, “This midline incision looks horrible, and we’re doing single-port.” Then, I started to do traditional extraperitoneal, which is going below the 12th rib or the tip of the 12th rib. I did a few of those, but then I was still getting some hernias, although the incision was small. Also, I was not so familiar with the retroperitoneal space, and it was a big learning curve because the retroperitoneal is a small space. Also, retraction was difficult. The good thing about single-port is you don’t have to use a balloon dilator to dilate the retroperitoneal space. You could do that under direct vision.

Still, I was not comfortable. If you’re doing a partial nephrectomy on a male kidney or you have a patient with high BMI, you are going to have a lot of perinephric fat, and lifting the kidney is difficult because you don’t have as much mobility. You also don’t have a large distance from one instrument to the other. You must keep all the instruments close or else you will collide. You are not going to see well.

For me, it was hard to retract the kidney. If I was going to do extraperitoneal—and I still wanted to do extraperitoneal—an idea came to me. If I do some sort of lower-abdominal incision, like a McBurney incision point, and maybe I’m a little bit more lateral to the McBurney point, then I can use my finger. I can go over the peritoneum and go to the retroperitoneal space, and that way I’ll have a better understanding because now I’m coming from the lower pole.

Initially, I got into the peritoneum a few times, but that is no big deal because of the way we had the placement of the port. Basically, we would be going—and it was a perfect transition for me because I could do transperitoneal if I got in there by mistake—and then I would do a standard peritoneal approach. But the good thing about this approach, I quickly realized, is that instead of coming from the midline where you are going to see the colon, you are going to see the duodenum, and you have to Kocherize them, and then you have to hold. If it is on the left side, you have to hold it with something because the bowel usually gets in the way of the hilum. But you have a single-port, and you don’t want another extra port. I realized that if you come from below, it is like going up the river.

If it is on the right side, you quickly mobilize the colon, and it’s going to fall away because you are coming from the lower pole now. Kocherize the duodenum, and then you are on the inferior vena cava (IVC). You go up the IVC, and you’ll find the hilum. It’s a lot easier, even if you do transperitoneal.

This incision is good for transperitoneal as well as retroperitoneal. For the retroperitoneal, I started to realize that if I do it from this angle, I don’t have to hold the kidney up as much because what I do is I go into the retroperitoneum, find the Gerota’s [fascia], and now I’m right above the psoas muscle and the kidney is above, and the kidney is being held up by the anterior peritoneal attachment. I don’t separate that perinephric fat from the peritoneum anteriorly, and so the kidney is held up, and I put my fourth arm of the robot on the top in this situation and hold the kidney up and move superiorly. Normally, I keep the camera at 12, but in these cases I change the location to 6 o’clock. I change it because I’m going to be looking down and going up the kidney, and then I am right on top of the psoas muscle. If I go medially, I’ll find the ureter, and I’ll find the IVC if I’m on the right side. If I’m on the left side, I’ll find the ureter immediately, and I’ll find the gonadal. I’m lifting the kidney, or the kidney actually stays up by itself with the help of the fourth arm. I advance the fourth arm as I lift up the kidney, and then I find the hilum right there. I’ll find the artery first laterally and then, immediately, the vein.

My approach to the retroperitoneum became very simple with this new approach, and it benefits the patients, eliminating hernia and reducing pain and providing improved cosmesis.

What anatomical landmarks do you use to target your SPAM incision?

Dr. Ahmed: If you want to do extraperitoneal, you move that incision a little bit more lateral near the anterior superior iliac spine. The first thing you see is the fascia, the main anterior abdominal fascia. You cut that. Then you see the external oblique, and you split it. Sometimes it could be lateral to that, so you don’t have to split. Cut the fascia and split the fascia. Next is the internal oblique. Split that one. Then the transversalis, and you split that. If you are a little bit lateral, you don’t have to actually split the muscle. All those fasciae convert and become one a lot of time, and you could just cut into that. Then you are going to see the peritoneum, so you have to go slow there. You don’t want to be too aggressive and cut the peritoneum. Once you see the peritoneum, you stop, and then you put your finger into the incision and stay above the peritoneum and go lateral. Then the peritoneum ends in the retroperitoneal space, and you can feel the kidney.

In terms of tools, you mentioned several instruments. You have the da Vinci access globe. You have the ROSI, the remote-operated suction irrigator. The last thing I think we should talk about is AirSeal. There are still people who do not use AirSeal, but it seems like it is essential for single-port. Do you agree?

Dr. Ahmed: You have to have some sort of continuous insufflator, either AirSeal or their competitor. If you do extraperitoneal, you want to work at 10 or less. Extraperitoneal is not really a true space, and so you make that space. You have a lot more absorption, and there have been reports, especially in prostate, that patients end up absorbing so much air they can get a pneumothorax. The good thing about AirSeal is you could set the pressure to 8-10, which allows you to place the suction on continuous mode.

If you don’t have the AirSeal, it’s harder to do extraperitoneal surgery with single-port, because you’re going to have the ROSI suction continuously. You’d rather keep it on continuously because to turn it on and off is just more headaches. If you have a regular insufflator, you end up losing insufflation, and on a regular device, keeping at high pressure will lead to subcutaneous air. In sum, keep a continuous AirSeal between a pressure of 8 and 10, and you keep continuous suction mode.

As somebody who has mastered the single-port platform, do you have any advice for surgeons who are beginning the process of learning it?

Dr. Ahmed: One thing I always stress is that it’s important to understand the anatomy. Focus on understanding the anatomy, how the prostate is connected to surrounding structures, the relation to the periprosthetic fascia, relation to the nerve, relation to the apex, and how the kidney sits in its own stratum. Also, focus on the fusion of the peritoneum and the Gerota’s [fascia], the perinephric fat, the relation to the source, and the relation to the IVC. I think once we understand the anatomy, then the single-port or any other approach becomes easier.

When I first used my single-port, my first 3 or 4 cases, I felt like my right hand was tied and I was just working with my left hand. But right now, when I sit on a single-port, sometimes I don’t even feel that I’m using single-port or multiport. Once you start using the single-port and you stay committed, you learn that there are functions, you learn how to bend the instrument, how to keep it straight, when to change the angle of the camera, and how to come in with these instruments so you don’t collide.

Start using it with a simple case. Do your first partial [nephrectomy] on an anterior 2-centimeter lesion and do it transperitoneal if that is what you are familiar with. Do it midline. Once you get comfortable, now you can try the McBurney’s or the SPAM incision. Try something totally different that is maybe beyond your comfort zone. That’s how you’re going to get good at it. Also, you will be using an approach that you never imagined before using the standard robot.

I also want to stress that to use the single-port is to start thinking about approaching the surgery in a different way. It is a different incision. Do not continue your intraperitoneal prostate. Now you have a tool that you could use to do an extraperitoneal prostate. Now you have a tool that you could use to do an extraperitoneal kidney. Now you have a tool that you could use to make a Pfannenstiel incision for a ureteropelvic junction repair. Your patients will appreciate it.

Akhil Abraham Saji, MD is a urology resident at New York Medical College / Westchester Medical Center. His interests include urology education and machine learning applications in urologic care. He is a founding and current member of the EMPIRE Urology New York AUA section team.