Remote surgery

Before Dr Jacques Marescaux performed the first ever remote surgery in 2001, the feat was largely thought impossible. At the time, the available communication technologies – such as cable and satellite – simply seemed too slow or impractical to transmit signals from a surgeon to a robotic system located miles away.

But then France Télécom, now known as Orange S.A., gave Marescaux and his team access to their highspeed terrestrial network. They set up a dedicated line from a control room in New York to three robotic arms in Strasbourg, France, with a network delay of just 155 milliseconds. From more than 6,000km away, Marescaux successfully removed the gallbladder of a 68-year-old woman in just under an hour.

That was 22 years ago. Since then, robotic surgery has gained traction: in the US, 876,000 robot-assisted operations were performed in 2020, up from 753,000 in 2018; from 2013-2018 in England, the UK’s National Health Service saw a 398% increase in robotic surgeries (2,452 vs 11,979). Yet, remote procedures have mostly been done in research settings.

One reason for this is the limitation of network speeds: for remote surgery, it should take less than 200 milliseconds for signals to pass from the surgeon to the operating room and back, explains Marescaux, who is the founder and president of surgical research and training institute IRCAD. “With 5G, we know that the majority of the time it is more,” he adds. But thanks to advances in surgical robotics and a wave of emerging solutions on the horizon, remote robotic surgery could become viable for more patients.

Minimally invasive surgery

Doctors have been performing life-saving surgeries without robots for years – so it’s worth asking: Why use robotic arms in place of human ones? Well, robots can make smaller, more precise cuts and have a wider range of movement than a human hand, which makes minimally invasive procedures easier to perform, explains Marescaux: “The robot will amplify what you do…and it offers a lot of freedom.” For patients, this may lead to less scarring and a faster recovery.

During operations, the robotic arms are controlled by the surgeon via a console, while a camera transmits real-time imagery of the patient to a screen in front of them. This technology is already being used in hospitals, but the surgeon is usually in the same building – often, they’re in the same room.

With a strong enough network, these procedures could be done from another city or even continent – in theory, at least. Some research has suggested that 5G could do the trick, but unless you have a dedicated line and perfect connection, relying on 5G for complex surgery between, say, two continents, is unrealistic, says Marescaux. From point A to B, “you can never be sure that the speed of the communication will be the same, [and] under 200 milliseconds,” he says. “That is very important for your brain. You cannot have a delay that changes.”

In 2020, doctors in China conducted four laparoscopic surgeries on pigs, from nearly 3,000 km away using a 5G wireless connection. The average network delay was reported as 264 milliseconds, yet the surgeons noted that the operations went “safely and smoothly”.

Others have explored whether an internet connection would suffice. Between 2003 and 2005, surgeons in Hamilton, Canada, performed 22 operations from more than 350 km away using a high-performance virtual private network. Mostly, the time delay was 150-200 milliseconds, but sometimes it exceeded 250.

Robots are currently used for a range of surgeries across urology, cardiology, gynaecology, head and neck, and more. And thanks to their enhanced movement range and precision, they enable certain operations which are traditionally done via open surgery to be performed using keyhole techniques, such as prostate removal and surgery for stomach cancer.

Were these procedures available remotely, there’s no doubt they would increase access to care – patients may otherwise need to travel to a specialist centre for gastrectomy, for example – while giving more people less invasive options for surgery.

Treating stroke

When treating stroke, it’s crucial to act within 60 minutes, known as the “golden hour”, to reduce the chance of long-term brain damage. Yet, reaching a neurovascular surgeon in time, most of whom are based in big city hospitals, is a major challenge.

Then, there’s the thrombectomy procedure itself, which can also be a complex and drawn-out process. The surgeon needs to manipulate a J-shaped wire through to the stroke site by rotating it outside of the body – but if it can’t navigate the sharp twists and turns of the vascular system, it needs to be taken out and replaced.

“It can take a very long time,” says Xuanhe Zhao, professor of Mechanical Engineering at MIT. “So we saw an opportunity to apply our intravascular robotic system to stroke treatment.”

The system uses a straight guidewire with magnetic particles inside, whose movement is manipulated by a magnet that’s controlled by a surgeon via a joystick. This allows for precise control over the wire’s movement once inserted, so it can be led straight to the clot, Zhao explains. “It’s just like playing a video game,” he quips.

While one robotic arm holds the magnet in place, another captures real-time, X-ray imagery of the procedure that the surgeon sees on a screen. At the patient’s feet is a remote-controlled unit that advances or retracts the guidewire. When the wire reaches its target, the system deploys a catheter which is followed by either drugs or a stent retriever – a kind of net that captures the clot and removes it.

All of this can be done in a matter of minutes, or even seconds, says Zhao. “It’s very fast, because all the navigation can be controlled by the magnet.” Currently, the system has been tested successfully on pigs from the next room.

While the system relies on network speed and connectivity, the guidewire itself moves slowly, so if you’re cut off briefly you can just stop and wait until you reconnect, Zhao explains. The system would be able to work on 5G, he adds.

“Stroke is the number one cause globally of long-term disability and the number two cause of death – the impact is even higher than cancer,” says Zhao. “The ultimate goal is that we’ll deploy this robotic system at hospitals… and neurosurgeons can control the robot from bigger centres and treat stroke remotely.”

Heart disease

“If you are a patient living in a rural location, and you have a heart attack, your local hospital may not have the expertise to open that up quickly and save your life,” says Dr Ryan Madder, section chief of interventional cardiology and director of the Cardiac Cath Lab at Spectrum Health. “We think we can reach those rural hospitals using telerobotics.”

Madder and his team have been exploring the possibility of using a robotic system to fix blocked arteries in the heart remotely – a procedure they’ve termed “telestenting”. “We know that it’s technically feasible right now, based on the research we’ve done,” he says.

To place a stent, a catheter is inserted into an artery and guided to the blockage. A thin, flexible wire is threaded through the catheter, and a balloon with a stent inside is passed over it. The balloon is inflated and the stent locks into place; the balloon deflates and is removed. Aside from leading the catheter to its target, the robotic system can perform the entire procedure. A robotic arm at the patient’s bedside applies force to drive the guidewires, balloon, and catheters, which is controlled via buttons and two joysticks in a separate room. The surgeon’s attention is fixed on a screen, which shows a real-time x-ray feed of the heart. In the REMOTE-PCI trial, published in 2017, this system was tested successfully while 55 feet away from the patient, using a Wi-Fi connection. In 2018, Madder used it to place stents in pig arteries from more than 100 miles away.

A year later, the team wanted to see how far the robot could be from the cockpit while still operational. From Boston, Madder placed stents in endovascular simulators in San Francisco – more than 3,000 miles away – using both wired and 5G wireless networks. “We think we can probably reach anywhere that has an adequate quality of service in the continental United States,” he says.

But there’s still a way to go before patients can access it, Madder adds. “We still need to understand a little bit more about how those robots function when the commands from the robotic controls are being passed over the network.”

Making remote surgery a reality

While robotic surgery is technically viable right now, we’re probably still a good few years away from remote operations becoming routine.

For example, Zhao’s team is planning to launch a company to bring their technology to clinics, with hopes of getting FDA approval within 3-5 years. However, he predicts it could take maybe a decade for it to be used remotely: first, big hospitals need to get to grips with it, before it trickles down to smaller centres.

It’s hard to say whether the proof of concept for widespread remote surgery will come from a routine procedure like stenting or an emergency operation like a thrombectomy. But either way, it seems clear that maintaining a consistent connection with the robotic system involved, or at least having a safety control in place for variations in latency, will be key to gaining approval from regulators and acceptance from the medical community.

In any case, remote and robotic procedures are requisite learning for the next generation of surgeons, says Marescaux. “Twenty-two years after what we have done, now everybody understands that this is the future.”