Researchers in Spain have developed a device that simulates the improved vision that a cataract patient can have before corrective surgery even takes place.

The scientists at the Spanish National Research Council’s Institute of Optics in Madrid compared the visual acuity obtained at different distances through a commercial trifocal lens (with focal points for close, intermediate and long focal distances), through the same lens simulated by a spatial light modulator, and through SimVis, a technology they developed that contains an optotunable lens working in a temporal multiplexing mode.

Researchers performed the comparisons on seven human subjects and on an artificial eye and found “a general good correspondence” in focal performance with the real and simulated multifocal lenses, according to the study published in Nature Scientific Reports.

The researchers developed SimVis to help cataract patients evaluate which of the several available multifocal lenses they want implanted. SimVis is a lightweight binocular visual simulator that can be worn alone or within a helmet. The new simulator can be wirelessly controlled by a mobile application or a tablet, allowing for control of the device’s lenses and tracking of the functional tests conducted on each patient wherever they are.

“The possibility of the patient experimenting vision with a multifocal lens before the surgery is very attractive to reduce uncertainty and to manage expectations,” said Institute of Optics researcher Susana Marcos in a prepared statement.

Marcos’ team at the institute’s Visual Optics and Biophotonics Laboratory has spent years developing technologies of simultaneous vision simulation aiming at evaluating visual quality with new designs of multifocal lenses before they are implanted or even manufactured.

“Visual simulators are an ideal technique to provide patients with a new realistic experience of multifocality before the implantation of a new intraocular lens,” Marcos said. “In addition, if the simulator is miniaturized and has a more practical design than the ones currently available in the market, benefits could multiply.”

“The response to multifocality depends on the subjects, but the real trifocal lens and the simulated one offered the same visual response through-focus in each patient”, added first author María Viñas.

The research council has licensed the SimVis technology to the company 2EyesVision S.L., a spin-off co-founded some of the study researchers and others.