Surgical robot was used to remove blood clot in eye of patient with retinal vein occlusion. Credit: KU Leuven Eye surgeons at University Hospitals Leuven were the first to use the surgical robot to operate on a patient with retinal vein occlusion. The robot, developed specifically for the procedure by engineers at Katholieke Universiteit Leuven (KU Leuven), uses a microneedle of barely 0.03 millimeters to inject a thrombolytic drug into the patient’s retinal vein. The vein is about as thin as a human hair.
The procedure shows that it's technically possible to safely dissolve a blood clot from the retinal vein with robotic support, researchers said. A phase 2 trial now has to show what the clinical impact is for patients with retinal vein occlusion, a disorder that can lead to blindness.
Researchers from University Hospitals Leuven and KU Leuven developed the surgical device as they studied a new treatment, called retinal vein cannulation (RVC), that addresses the cause of retinal vein occlusion by removing the blood clot in the vein.
RVC is a promising method that requires an eye surgeon to insert an ultrathin needle into the vein and inject a medicine to dissolve the clot. Since the vein is so thin, only 0.1 millimeter wide, eye surgeons would need to manually inject the drug by holding a needle perfectly still for about 10 minutes. That would be too risky as the danger of damaging the vein or retina would be far too great.
To enable the procedure, researchers from the KU Leuven Department of Mechanical Engineering developed a robotic device that allows the surgeon to insert the needle into the veins in a very precise and stable way. Once the needle is inserted, the robot holds it perfectly still.
Unlike most surgical robots, this robot requires no joystick to operate. The eye surgeon and the robot co-manipulate the instrument, as shown in this video.
The surgeon guides the microneedle into the vein while the robot eliminates any vibration of the needle, thereby increasing the level of precision more than tenfold. After locking the robot, the needle and the eye are automatically stabilized. The surgeon can then inject the drug, in this case Ocriplasmin, into the vein in a controlled way. The drug then goes to work to dissolve the blood clot.
The procedure was first performed January 12 and doctors report that the patient is doing well and undergoing eye rehabilitation. In a subsequent phase 2 trial, physicians will study the clinical effects of the procedure.
“We are extremely proud that our robot enables us to perform eye surgery that was previously impossible to perform safely,” said Dominiek Reynaerts, a professor in the KU Leuven Department of Mechanical Engineering. “This brings us one step closer to commercializing this ground-breaking technology.”
An estimated 16.4 million people worldwide suffer from a blocked retinal vein caused by thrombosis in the blood vessel. In Belgium, there are about 25,000 patients.
