Novel IOL designed to improve image quality in periphery
A novel IOL, designed to control field curvature and reduce peripheral astigmatism, holds promise to provide superior image quality in the whole visual field, according to one presenter at the virtual Association for Research in Vision and Ophthalmology meeting.
“Current intraocular lenses are designed to optimize focus at the eye’s central retina, with not much attention to their off-axis performance,” Pablo Artal, PhD, said. “In addition, IOLs are very thin in comparison with our natural lens. The reason is obvious, because we favor surgery through a small incision, but from the point of view of the optics in the periphery, the impact can be important, and most standard lenses provide a wrong field curvature.”
In other words, standard IOLs are satisfactory in restoring good vision on axis, but the image quality they provide in the periphery can be poor.
By using ray tracing optimization techniques, an intraocular meniscus IOL that mimics the natural lens to provide optimized field curvature and lower peripheral astigmatism was designed.
“The lens has a concave-convex profile, with an anterior aspheric concave surface and a posterior aspheric convex surface. The curvature radius of the posterior surface is smaller than that of the anterior surface by a factor ranging between 2 and 6. We called this lens ArtIOL,” Artal said.
The new IOL was tested in a custom-built realistic artificial eye model and compared with a standard monofocal IOL. Both lenses performed equally well on axis, but with images recorded at 40°, the meniscus lens showed significantly higher definition and better contrast.
In an optical simulation, Artal demonstrated how much clearer vision could be on the periphery, showing changes in the walking surface, like a step, that could go undetected with a standard lens, resulting in potential accidents.
“We are now performing clinical studies, testing quality of vision in the periphery,” he said. – by Michela Cimberle
Artal P. An intraocular lens to improve field curvature and off-axis astigmatism in pseudophakic patients. Presented at: Association for Research in Vision and Ophthalmology annual meeting; May 6, 2020 (virtual meeting).
Disclosure: Artal reports he is one of the inventors in a patent application related to the technology described.