Surgeons in the U.K. have completed a first in the world of optometry — operating inside the human eye via a robot.

The surgery, which removes fine membrane growths on the retina, is crucial because if left untreated, these growths can distort vision and potentially lead to blindness.

An eye’s retina is the thin layer at the back of the eye which converts light waves into nerve impulses that the brain reads as images. When the retina is impaired, a person could experience fogginess, black spots, or even complete vision loss.

As of right now, this delicate surgery is being performed by optometrists, even though there are plenty of risks involved. Considering the size of the eye, the delicate nature of the retina — the retina is the width of one-tenth of a human hair — and the narrowness of the eye’s opening, even the most skilled doctors can cut too deeply and cause scarring and hemorrhaging. In fact, researchers explain to NBC news that even the simple pulsation of a surgeon’s blood within their fingertips is enough to affect the accuracy and depth of the cut.

So, this is where the robots come in.

In the trial, completed by surgeons in the U.K. and led by Oxford University researchers, 12 patients underwent membrane removal surgery, six had the operation completed by a doctor and six underwent a new robotic technique.

The findings showed that the six patients who were operated on by robots experienced less bleeding and significantly less damage to the retina during the surgery.

The robot’s hand is designed with seven independent motors that have the ability to make movements as exact as one micron. It interacts within the eye through a single hole with a diameter smaller than one millimeter, with the surgeon controlling its actions via a joystick and touch screen. This robotic system was first developed by Dr. Marc de Smet and Maarten Steinbuch in the Netherlands back in 2011. It was first used on a human, a 70-year-old priest from England, in September 2016.

It is no secret that robots are complex pieces of machinery with multiple intricate parts. This includes printed circuit boards, which have risen to popularity due to machine-assembly, which provides a 75% faster output rate than the industry average.

Scientists believe this new robotic system has the ability to change retina surgery for the better. Dr. Robert E. MacLaren, the leader of the surgery trial experiment, explained to Live Science,

“The robotic technology is very exciting, and the ability to operate under the retina safely will represent a huge advance in developing genetic and stem cell treatments for retinal disease.”

Right now, this surgery is only being performed in the United Kingdom.