Eyeworld

26 Ophthalmology Business • December 2016 "Most visual simulators are based on adaptive optics," she said, explaining the technique that can be used to mimic corrections. She said these types of simula- tors are large and bulky compared to SimVis, which in its latest iteration is wearable and allows patients to see the world through the instrument, providing them with the experience of seeing the correction at varying distances with different IOL options. "Multifocality is simulated by rapidly varying the optical states of the lens and controlling the state of the lens (focus position) and the amount of time the lens remains in any given state (energy dedicated to a particular focus). This variation is faster than the visual fusion frequen- cy, so the temporal multiplexing produces retinal images that are per- ceptually static," the study authors wrote. The research published in Optica described nine subjects between 20 and 62 years old who tested the de- vice, which simulated three monofo- cal, two bifocal, and two trifocal lens- es. The researchers measured visual acuity and perceived visual quality for near, intermediate, and distance vision, comparing the different types of correction. Overall, the researchers found "large inter-subject variability in the preferences across lens designs, with each subject revealing a differ- ent preference pattern," which one might expect. The study participants did not have cataracts, but Dr. Marcos said they have tested the device in cata- ract patients and found it functioned well despite a clouded lens. "The ranking of the different designs and their preference was perfectly achievable," she said. Dr. Marcos called the patients' preferences to the different correc- tions subjective, but said they are "based on a series of well-established comparisons and a statistical re- sponse for what lens is better." The instrument can also simulate side effects like halo, allowing patients to experience what that will be like before selecting a multifocal IOL. The device is programmable for the specific corrections offered by IOLs currently on the market, but Dr. Marcos said that it could be used in the development process for new IOLs as well. "From a commercial perspective, the primary customers would be the ophthalmologists who want to have the patients try the lenses before they're implanted in their eyes. The instrument can also be used by intraocular lens or contact lens manufacturers that can try different designs before they're manufactured or commercialized. In our lab we're working with some intraocular lens companies before an intraocular lens is launched," she said. Because multiple lenses can be tested on the same subject—the same brain—it allows researchers and man- ufacturers to better compare designs. The SimVis device evolved from a handheld, monocular piece to one that is even smaller, binocular, and can be worn by the patient. This al- lows the patient to walk around with it and experience it in, for example, outdoor environments; in addition, the technician can program it to test patient preference with monovision or where one eye gets a multifocal IOL and the other gets a monofocal IOL, for example. Dr. Marcos thinks that the latest generation of the prototype is close to being ready for the clinician. "The next research step is to bring it to the ophthalmologists' and optometrists' offices and have it used and prove the commercial value of the instrument," she said. "[We want to prove] that it is increasing patient satisfaction when the instrument is used, and this increases the success of the multifocal intraocular or contact lens prescription." OB Reference 1. Dorronsoro C, et al. Portable simultaneous vision device to simulate multifocal corrections. Optica. 2016;3:918–924. Editors' note: Dr. Marcos is co-inventor of three patents on SimVis, and cofound- er of 2Eyes Vision, a spinoff company that commercializes SimVis. Contact information Marcos: susana@io.cfmac.csic.es continued from page 25 For more information on the SimVis headset, go to www.2eyesvision.com. Source: 2Eyes Vision

• Cover