Plastic surgeons have carried out the first human trial of a robot performing “super-microsurgery,” a term referring to surgery on vessels that range from 0.3 to 0.8 millimetres.

Previous surgical robots, developed 20 years ago, have only been able to work with precision and accuracy down to one millimetre – meaning they have matched human surgeons, but not outdone them.

As reports of the robot breakthrough have noted, only a small number of surgeons in the world can perform super-microsurgery – because of its demands for precision, and intolerance for even the smallest hand tremors.

The surgery was carried out on women suffering a crippling complication of breast cancer surgery that is difficult to treat.
The surgical trial

The researchers, from Maastricht University Medical Centre, tested the robot's effectiveness and safety against that of human surgeons on a group of 20 women with lymphedema, a condition related to breast cancer in which excess fluid collects in tissues, causing swelling.

It's worth understanding how this happens. Lymph is the thin, clear fluid that circulates throughout the body to remove wastes, bacteria, and other substances from tissues.

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During breast surgery, patients have at least two or three lymph nodes removed from under the arm. In cases where the cancer has spread, it tends to move into the underarm lymph nodes first because they drain lymph from the breast.

Surgery and radiation may cut off or damage some of the nodes and vessels that lymph moves through. Eventually, the flow of lymph overwhelms the remaining vessels, resulting in a backup of fluid into the body’s tissue.

The surgeons planned to relieve these symptoms by connecting lymph vessels to nearby veins, thus bypassing the affected area. This surgery is called Lymphaticovenous anastomosis, a relatively new procedure requiring extreme precision.

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Lymphedema commonly occurs following breast cancer treatment and leads to swelling and localized fluid retention. Photo: supplied

The women in the trial were split into two groups: one group received solely human surgery, the other group was operated on by surgeons using a robotic system called MUSA, manufactured by a Dutch company called Microsure.

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The surgical robot is activated by foot pedals. The high-precision surgical instruments are controlled using forceps-like joysticks. The human surgeon's hand movements are converted into smaller and more precise movements, which are then performed on the patient by a set of "robot hands".

The device also stabilises and eliminates any tremors, making the procedure more controlled and easier to perform.
 How did the two groups compare

The trial wasn't designed to see if the robotic system was superior to surgeons working alone. However, the group tended to by robots healed slightly more quickly – beyond that, humans and human-guided robots were on par.

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A successful Lymphaticovenous anastomosis as performed by a robotic system that is guided by, but eliminates tremors from, human hands. Photo: Maastricht University

But it's important to remember that the humans working alone were elite surgeons. The real worth of the Microsure robot will come if proficient, every-day surgeons can replicate these results using the system. This will mean the niche area of super-microsurgery can be made available to more patients.

But it also opens the way for surgeries that are beyond even the elite group – that is, that are ordinarily impossible to perform by hand – to become possible.

The researchers predict this will "improve patient outcomes and lower healthcare costs thanks to fewer complications and post-operative treatments."

All of that is down the track – after many more trials have established the safety and efficacy of the system beyond doubt.