As part of a long history of pioneering optical coherence tomography (OCT) technology that has revolutionized patient care for adult and pediatric patients, Duke clinicians and scientists have developed a robotically aligning OCT system that captures retinal images while allowing the system operator and patient to maintain a safe physical distance from each other.
The investigational robotic OCT system can acquire retinal OCT images without the need for chin/forehead rest touchpoints for stabilization or the need for an operator of the system in close proximity—features that are particularly important during the COVID-19 pandemic.
Duke clinician scientist Anthony Kuo, MD, associate professor of ophthalmology and corneal specialist; and research scientist Ryan McNabb, PhD, developed the system based on a prototype developed by Pratt School of Engineering collaborators Mark Draelos, MD, PhD, Pablo Ortiz, and Joseph Izatt, PhD.
“This is the first, to our knowledge, robotically aligning OCT system designed for potential clinical use for patient imaging. This system offers the ability to safely distance operator and patient while providing the additional imaging benefits from active motion tracking and compensation,” says Kuo.
The system operates through the use of two sets of cameras tracking the patient’s face and the pupil of their eye allowing the robot to independently find the patient’s eye and align with it. If the patient moves, the robot will move with the patient. The system is robust enough to capture small motions and tremors patients may have, and it corrects for them in a way that current systems cannot. “This new technology will improve accessibility and is more comfortable for patients. The robot can adapt for those who have mobility issues or may be wheelchair bound, and potentially for children that have a hard time sitting still,” McNabb says.
The development extends Duke’s position as a pioneer in OCT technology, which began with the work of Cynthia Toth, MD, Joseph A.C. Wadsworth Distinguished Professor of Ophthalmology, and Joseph Izatt, PhD, Michael J. Fitzpatrick Distinguished Professor of Engineering, both having dual appointments in each respective department. Toth and Izatt have developed applications for intraoperative OCT that allow more precise ophthalmic surgery and a handheld OCT unit that is particularly useful for infants and children. “We are proud to continue the well-recognized contributions of Duke researchers who have encouraged us and led the way to make this project possible,” says Kuo.
The system could potentially expand access for those in rural areas who may have limited access to ophthalmologists, and it could be used in telehealth. Once the robot is deployed to record the eye images, that data can be passed digitally to wherever it is needed.
“The OCT images could be taken by the robot where the patient is and then sent electronically to specialty centers for reading,” says Kuo. “There’s a tremendous amount of potential.”
When physical distancing became important due to the COVID-19 pandemic, Kuo and McNabb expanded their work such that the robot can now be operated remotely, keeping space between patient and operator. “The robotic OCT system is touchless–no contact with a chin rest or forehead strap–and with the operator keeping a safe distance behind a barrier more than six feet away,” Kuo says. “When we began development, we of course had no idea that we would be dealing with a pandemic, but this is certainly relevant for the future of eye imaging and for the future normal.”
Patients are asked to fixate on a target behind the robot and are in control during the imaging process through the use of a foot pedal to activate the robot. As soon as a patient takes their foot off the pedal, the robot retracts away, which increases the comfort level in patients who might be apprehensive about having a robot near their eye.
Subjects have been enrolled in a research study to test the accuracy with the current system. These subjects encompassed a range of demographics–age, race, and gender, for example. “Even if people are a little hesitant at first, most everyone who has been imaged with the robot becomes comfortable with it and likes the freedom of sitting freely without constraints to be imaged,” McNabb says. “Early results are promising that the robotic OCT is just as accurate as traditional technology.”
“This discovery could change the way imaging is performed in clinical settings, and I’m glad that Duke continues to lead the way as an innovator in ophthalmic imaging,” Kuo says.