High-precision with robotic assistant

A new surgeon-controlled robot can nearly eliminate hand tremor in retinal surgery

Leigh Spielberg

Posted: Tuesday, July 9, 2019

Koorosh Pouya MD performing the first robotic peeling with the Preceyes system. Courtesy of Koorosh Faridpooya MD

Vitreoretinal surgery requires a level of precision that pushes the boundaries of what is humanly possible. The need for accuracy is high and the margin of error is very low, considering the fragility of the tissues in the posterior segment. The successful outcome of such vitreoretinal procedures requires fine motor skills of the greatest precision.

A Dutch company, Preceyes, has developed an intuitive, surgeon-controlled robot to assist surgeons. The robotic assistant, called the Preceyes Surgical System (PSS), scales down the movements of the surgeon’s instruments inside the eye, translating larger movements into smaller ones. By doing so, it nearly eliminates hand tremor, adding a level of precision to what are already finely tuned manoeuvres.

The precision of robot-assisted movements in the eye is enhanced at least 10-fold and made tremor-free as compared to manual movements by the surgeon. This allows for an intraocular precision of 10 microns or less. This precision, combined with standby functionality and automatic instrument retraction in case of patient motion decreases the surgeon’s stress during the surgical procedure.

The goal of the robot is not to replace the surgeon, nor is it intended to perform surgery independently. Instead, “the robot supports the surgeon by improving existing surgery and enabling the development of new, high-precision treatments”, says Preceyes’ Chief Medical Officer, Marc de Smet MD.

The PSS assists not only with the movements, such as membrane peels and subretinal injections. It can also be used simply to hold an instrument, such as a light pipe used to illuminate the retina. This static positioning eases surgeon strain and allows him or her to concentrate on the task at hand.

“We’re certainly not the first to approach the concept of vitreoretinal robotics, but we were the first to get into the eye,” said Dr de Smet, who described the four different robotic concepts in eye surgery: the handheld tool, instrument comanipulation, instrument telemanipulation and magnetic control. Each varies in the degree to which the robot can filter tremors, scale motion and allow automation.

Preceyes collaborated with the Rotterdam Eye Hospital (REH) to initiate the world’s first clinical trial of a robot in routine vitreoretinal surgery. The goal of the study was to evaluate the robot’s ability to improve both the precision & reproducibility of surgical tasks in everyday vitreoretinal surgery, seeking to reduce the burden on surgeons and improve outcomes. Specifically, can the PSS robot help the surgeon perform the peel more precisely and reproducibly than the surgeon alone?

To answer this question, Preceyes and the REH joined forces to initiate a randomised, prospective, open-label surgical intervention study to compare robotic assistance to standard manual surgery. A total of 15 patients are being randomised for this study: 10 patients will be operated on using the robot and the remaining five patients will be operated on in the traditional manner. The outcomes include feasibility and safety profile, surgery duration; number of attempts required to initiate and peel the membrane; and anatomical and functional outcomes at one and three months after surgery.

Koorosh Faridpooya MD, senior retinal surgeon and primary investigator at the REH, has been collaborating with the Preceyes team. He recently performed the first complete robot-assisted peeling of an epiretinal membrane (ERM). “This is an important step in vitreoretinal surgery. It was the first time that all steps other than the vitrectomy and laser, were carried out during an a complete ERM peeling with robot assistance. The robot helped increase the accuracy of peeling, which is the crucial component of the procedure. We therefore expect that we will be able to reduce the number of complications and ultimately improve patient outcomes. The robot will allow us to develop new revolutionary treatments for some eye diseases that till now are almost impossible to perform manually.”

Dr Spielberg using the PSS robotic system coupled to the EyeS simulator during the 18th EURETINA Congress in Vienna

As a vitreoretinal surgeon myself, I was recently invited to test the PSS. I was most impressed with the scaling down of movement and the intuitive nature of the robot’s control mechanism. The scaling down of movement can be compared to the stabilising effect of a gimbal, an electronic tool used in cinematography and is now available to consumers. A gimbal smoothens the motions of a video camera, eliminating abrupt movements and shaky images, vastly improving the quality of the finished product.

Dr de Smet echoed my sentiments, noting that other surgeons who had tested the robot found “the use of the forceps fully operated by the robot with multiple grabs to peel a membrane as the most impressive part of the operation, closely followed by the fact that interchangeable instrument tips can be placed on the robot to carry out different tasks”, before adding: “The surgeon can, in essence, choose the instrument he or she needs and use it with the robot, and use it with high precision.”

Marc de Smet: