Robotic assistance brings increased precision to vitreoretinal surgery
Robotic assistance brings increased precision to vitreoretinal surgery which can enhance the success and safety of existing procedures and provide new interventional opportunities, according to Marc de Smet MD.
Dr de Smet, co-founder and Chief Medical Officer of Preceyes BV, Eindhoven, The Netherlands, described a platform that his company has been developing over the last 10 years.
The PRECEYES Surgical System is comprised of a table-mounted instrument manipulator that holds the surgical instrument and copies the movements made by the surgeon using a second component, the motion controller. As designed, the compact system can be easily integrated into current operating room environments, and it can be utilised by surgeons without being intrusive while they are working in their standard position with existing operating microscopes or a heads-up viewing system.
The robotic arm filters out hand tremor and has scalable motion so that it moves faster when in the periphery and then more slowly as the instrument tip approaches the retinal surface. The system has positional precision of about 10 microns, which surpasses the accuracy limits of human physiologic performance by about 10-fold.
“Surgeons may ask if there is really a need for the better precision provided with robotic assistance. Testing shows that in the X-Y direction, humans are virtually as good as the robot regardless of experience, although younger individuals may perform better than their older colleagues. When moving in the Z direction and entering tissue, however, more experienced surgeons can do better than their less experienced colleagues, but a robot will still do best,” said Dr de Smet.
The system is designed to be ergonomic so that it can be utilised without any anatomic limitations in up to 98% of heads. So far, there is only an arm that allows a temporal approach, but development of a nasal arm will be an easy task, Dr de Smet said.
The robotic arm gives broad access into the eye and helps prevent some motion of the eye itself. The motion controller provides an intuitive working environment for the surgeon because it places the point of motion of the hand at the tip of the instrument located in the eye.
“The rotation point of the controller lies above the surgeon’s hand. It thereby creates the feeling of manipulating the instrument tip inside the eye and eliminates rotational force,” Dr de Smet explained.
The system also allows surgeons to rapidly change instruments while staying focused on the retina. It has positional stability and memory.
“Because the robot can memorise the position of the instrument, the surgeon can transition to perform another task and come back to a previous location,” added Dr de Smet.
In September 2016 at John Radcliffe Hospital, Oxford, UK, Robert MacLaren MD used the PRECEYES Surgical System to perform the world’s first human robot-assisted vitreoretinal procedure – an epiretinal membrane peel. Now funding is being sought to enable expansion of clinical testing to involve more patients, more centres, and additional applications, including procedures that are currently part of the vitreoretinal surgery repertoire and novel techniques.
As described in two published articles, the robotic system has been used successfully for retinal vein cannulation and intraluminal injection of ocriplasmin to release experimentally-induced vein occlusions in animal models. (de Smet MD, et al. PLoS One. 2016 Sep 27;11(9):e0162037. de Smet MD, et al. Release of experimental retinal vein occlusions by direct intraluminal injection of ocriplasmin. Br J Ophthalmol. 2016;100(12):1742-1746)
Dr de Smet noted that further development of the robotic system includes work on imaging integration that may include visualisation capabilities built into the instruments themselves. He provided an example of a prototype in which movement of the robotic arm is controlled through referencing to landmarks on an optical coherence tomography image.
Marc de Smet: firstname.lastname@example.org