Last month, Phoenix Children’s Hospital became the first health system in the U.S. to deploy Medtronic’s Stealth Autoguide platform, which robotically assists neurosurgeons for more accurate positioning of instruments during procedures.
The cranial robotic guidance platform provides real-time visualization, feedback and robotically assisted movement to allow surgeons to accurately align with surgical plans. The system integrates withMedtronic’s Stealth Station surgical navigation system and Midas Rex surgical drill technology to improve workflow efficiency in an operating room. Procedures where the system can assist surgeons include placement of biopsy needles, the placement of stereo electroencephalography (stereo EEG or sEEG) anchor bolts to enable placement of depth electrodes, and support for laser ablation.

Dr. P. David Adelson, Phoenix Children’s Hospital.
At Phoenix Children’s, P. David Adelson, division chief of neurosurgery and director of the Barrow Neurological Institute (BNI), has performed at least two procedures (an sEEG procedure and laser ablation) with the new system on patients with epilepsy. Robotics Business Review spoke with Dr. Adelson about the hospital’s interest in the system and the benefits for surgeons using the robotic guidance system.
Easy integration
Q: How did you first get interested in the possibility of robots being used in neurosurgery?
Dr. Adelson: Over the last few years, there’s been a number of new entries into neurosurgical robots. Throughout the U.S., we’ve seen increasing robotic technology for a lot of different aspects of healthcare and surgery. But with regards to neurosurgical robots, particularly cranial, there were a number of excellent technologies that were very interesting.
The big issue for me was how easily would it be to integrate these into our present workflow. If you have to add new software for guidance, or new software that changes what you do or how you do it, then obviously there’s an extensive relearning and a high learning curve.
Q: How did you narrow it down to selecting the Medtronic system?
Dr. Adelson: Number one was the size, because it married into the technology that we already were employing – the Stealth Navigation System, as well as some other technologies in which we would be using the new robotic device. We had worked with Medtronic in the past on a number of different technologies, including the image guidance system and the laser ablation technology. This seemed to marry very well with that. The robot is also markedly smaller than its competitors, and so much easier to integrate into the operating room as an assistive device.
Second, it increased our efficiency of doing these procedures. When we were researching the different technologies, I was being sold on the fact that we could do an operative plan in eight to 12 minutes. I was already doing these in eight to 12 minutes, so I didn’t see what was going to be the added benefit with this significant investment. But the Medtronic one clearly led to increased efficiency – for us it’s actually cut the time in half.

The Stealth Autoguide platform integrates with the Medtronic StealthStation to robotically assist placement of instruments for cranial procedures. Image: Medtronic
Lastly is the accuracy – I felt very comfortable using their present technology getting 0.2 to 0.5 millimeters of accuracy. With a frame-based system you could get to 0 to 0.2. So this robotic device gives us that type of accuracy without having to use a frame. A frameless approach saves time, saves anesthesia for the patient, and ultimately gives us the same accuracy.
Accuracy and speed
Q: How important is accuracy in terms of some of these procedures? From a layman’s perspective, is there really that big a difference between 0.3 and 0.5 millimeters?
Dr. Adelson: That’s a great question. I guess if it’s your brain, you’d want it as close as it can be, but it’s not as simple as that. In many situations it’s not as important, but in certain situations it’s very important. If we have only a three-millimeter lesion that’s deep in the brain that we have to navigate across segments, then the accuracy is very important to avoid blood vessels, to avoid particular tracks in the brain, and to try to get to deep locations in a safe way. In that case, the accuracy is quite useful.

Stealth Autoguide cranial robotics guidance platform in the operating room with the StealthStation platform visible in the background. Image: Medtronic
Q: For pediatric patients, is accuracy a bigger deal, because of the body type of a child versus an adult?
Dr. Adelson: We always make a joke that children are not small adults, and I think that’s very true. Some of the lesions and types of problem that we’re using this robot for are quite different. For example, for epilepsy if they have a hypothalamic hamartoma, sometimes these lesions are only three millimeters in diameter. The accuracy and targeting for these are very important – we don’t see these types of lesions in adults. So the robotic technology is useful in certain pathologies that are unique for children. I’m sure there will be unique pathologies that the robot will be used in adults as well.
It was really a privilege and truly enjoyable to work with Medtronic to roll this out for children, because children often don’t get first out-of-box technologies. Often it’s done in adults, and then OK, the kids get kind of the layover – so I think this was wonderful for Medtronic to work with us to roll it out with us.
Q: What reaction do you get from either patients or parents when you tell them about the robotic system?
Dr. Adelson: A question came up with a family that asked, ‘Is the robot going to do the surgery?’ and I said, ‘No, that’s not how it works.’ The two patient families were on board, very interested in the technology as I explained how we were going to be using it.
Q: What were your thoughts from the two procedures you’ve done?
Dr. Adelson: The first one was a stereo EEG where we placed 10 electrodes, and that’s how I knew we could cut the time. As I said earlier, I was a little skeptical because I could already do this in eight to 12 minutes. We were doing them in four to five minutes [with the robot]. So that decreased anesthesia time for that child, and decreased operating room time. When you’ve got that many operative plans, the robot increasing your efficiency that way clearly saved us at least a half hour.
[In the second case], we were marrying the image guidance system with the robotic technology and laser ablation in order to treat a young woman with intractable epilepsy. We used it with two probes, and all of them have gone where we needed them to go, which has been fantastic.Q: Does the extra time now allow you to do additional procedures, or is it more of a scheduling thing where you can schedule procedures faster than what you could have done before?
Dr. Adelson: The hospital would like to know that I’m scheduling more surgeries – that would be fantastic (laughs). But for us, it’s about cutting down the time that patients are exposed to anesthesia, especially young children. They wake up easier if they’re not under anesthesia as long. Overall, we like to think that decreased length of stay in the hospital and decreased time in the operating room is better for health care, economics, and those kinds of things.
Medtronic’s Dave Anderson on modular robotics, and standardizing procedures
Robotics Business Review also spoke with Medtronic’s David Anderson, vice president and general manager, enabling technologies, about the goals of the Stealth Autoguide, the possibility of an all-in-one robotic surgery system, and allowing surgeons to standardize procedures in complicated surgeries.
Q: In a general sense, what was the goal of developing the Stealth Autoguide robotic system to assist in cranial neurosurgeries?

Dave Anderson, Medtronic
Anderson: Our goal is to take procedures that are more art and unpredictable today and make them more standardized, moving more from art to science. We know the very best neurosurgeons can achieve those best outcomes – but how can we have an approach that standardizes the more simple steps of the procedure?
The best neurosurgeons, including Dr. Adelson, can be very accurate, it just takes them a long time. More standard neurosurgeons, who may not be the best, are going to struggle even getting to that accuracy. With robotics, you can have that accuracy with confidence and you can get there quicker.
Q: What procedures within the cranial surgery space were you looking to improve with the Stealth Autoguide?
Anderson: There are three categories of procedures today, and part of our goal is to expand that usage as well. Two of the three that are very high volume are tumors – doing biopsies and ultimately surgical resection. Tumor is a high volume, typical cranial neurosurgical procedure. Next is epilepsy depth electrode placement. Third, the treatment is laser ablation.
Epilepsy depth electrode placement is very time consuming, as you have to place many of these electrodes to map the brain. That’s where robotics helps a lot in speed and accuracy, because instead of spending several minutes with each electrode, you can do that in seconds with the Stealth Autoguide.
Q: You mentioned you were looking to expand the types of procedures that you can do with the system. What’s next?
Anderson: Probably the next expansion for us is deep brain stimulation electrode placement. It’s similar to epilepsy depth electrodes, but it’s a permanent implantable electrode.
Q: Was the Stealth Autoguide specifically designed for these kinds of cranial procedures, or could this technology be applied to other procedures for other parts of the body?
Anderson: It’s a great question. Our perspective on robotics is that one size does not fit all. A simple analogy would be that you could have a minivan, but is that the best weekend vehicle for going down the coast, or the best one to haul a boat? We designed the robot specifically for cranial neurosurgical procedures based on its accuracy and ability to integrate into [a surgeon’s] workflows.
If you were to use this for spine [procedures], the challenge is it doesn’t have the rigidity to cut bone the way you would ultimately need. Our Mazor X Stealth Edition platform is a much more rigid platform, and our plans are to expand that into bone removal, for example. If you then look at general surgery, you’re really focused on tele-manipulation of tissue. It’s a whole different capability set you need to have there, and it’s not as focused on this sub-millimeter accuracy. So yes, it was designed for cranial neurosurgery.
Q: What is your thoughts on a modular robotic system that could handle procedures on different parts of the body? Are you hearing from hospitals about this, or do they understand the minivan vs. truck vs. car approach?
Anderson: Could we someday have a modular solution that you plug and play end effectors to get the different needs possible? I think we’re not there today technology-wise, and that’s part of the reason we’ve purpose-built it where when we need rigidity, we’re going to have a platform. If you look at our Mazor X Stealth edition by size compared to Stealth Autoguide, it’s 10 times the size – the point being it needs to build in a level of robustness to handle these capabilities that you would never need for cranial surgery. Likewise, if you have this large piece of equipment that is doing more heavy things like bone removal, it’s going to be more difficult to have the sub-level millimeter accuracy that you need in brain surgery.
Could this someday converge in a way that one could do it all? It’s possible, but we’re not willing in the early adopter phase to sacrifice requirements.
Q: If there isn’t demand from the hospital space to do a modular approach, how can the company help drive down the cost of these systems so more hospitals can adopt them without blowing their budgets? As many hospitals look at robotics procedures, they can see the advantages, but then cannot afford to have 10 different robotic systems in a hospital.
Anderson: I think this question will apply much later in the adoption curve in a low-volume center. If you look at our high-volume centers, they’re going to keep the robot completely busy in the procedures they’re doing. For cranial surgery, there’s no doubt our cranial neurosurgeons can use Stealth Autoguide all day, every day, and probably get two or three of them.
There could be a point down the road where this happens, where lower-volume centers want robotics, but they don’t have the procedural volume. But at this stage, the volume actually keeps a purpose-built robot fully utilized.
Q: Will volume then help drive the price down, or are there additional technology advances that can help lower the cost of components?
Anderson: It’s both volume and technology advancing, especially in the basic building blocks, such as processing power, visualization and the technology in cameras for visualization, and the robot arms themselves. Both volume and technology advances will be able to deliver more technology at a lower price.
Q: You mentioned the company is looking to reduce the number of steps in a process through robotics. Are you happy with the number of steps you’ve achieved with the Stealth Autoguide, or do you think moving forward you can reduce more steps?
Anderson: We’re very pleased with the first generation. From our perspective, our goal is to improve the clinical and economic outcomes, and procedure time is a big part of that. Then it’s standardization, the accuracy that comes with standardizing. What we’re doing in the first launch and release is providing the platform that can enable speed and accuracy. As we iterate on it, we can take those next steps of reducing procedure time further and standardizing more. We’re pleased with where we are, yet we recognize that this is the beginning of a platform we can do more with.