SAN FRANCISCO — Blind patients with no or bare light perception implanted with a visual cortical prosthesis have been able to perceive phosphenes and reported functional improvements 12 months after implantation, according to a speaker here.
“All of our patients, in general, have improved during the 12-month time frame,” Nader Pouratian, MD, PhD, said at the American Academy of Ophthalmology annual meeting.
Pouratian presented the interim results of the Orion visual cortical prosthesis system (Second Sight Medical Products) early feasibility study. Six patients were implanted with the device, which directly stimulates the visual cortex and bypasses the eyes and optic apparatus. The implant receives a signal from a camera in a pair of sunglasses worn by the patient. Patients who could previously see and had blindness caused by anything other than damage to the visual cortex were included in the study, Pouratian said.
The device demonstrated a favorable safety profile at 12 months. Five nonserious adverse events and one serious adverse event, a seizure, were reported. However, four of six patients did not experience any device- or procedure-related adverse events, he said.
All subjects perceived phosphenes at 12 months after implantation, Pouratian said.
“Most importantly, of 60 contacts we implanted over the primary and secondary visual cortices, the vast majority of those contacts resulted in a perceived phosphene,” he said.
In functional low-vision observer-rated assessments, in which trained observers rated the impact of the Orion implant on patients’ well-being and functional vision, five patients experienced positive improvements and one patient experienced mild positive improvements in their lives after 12 months, Pouratian said.
In comparison to the Argus II (Second Sight), the Orion demonstrated at least an equivalent performance after 12 months, he noted. – by Robert Linnehan
Pouratian N. Orion visual cortical prosthesis system early feasibility study: interim results. Presented at: American Academy of Ophthalmology annual meeting; October 11-15, 2019; San Francisco.
Disclosure: Pouratian reports he is a consultant with Second Sight Medical Products.