Pre-clinical methods to evaluate photic phenomena in intraocular lenses.

A new system and methodology are introduced to evaluate photic phenomena induced by different intraocular lens (IOL) technologies using a "see-through" IOL analyzer system in phakic subjects. Nineteen phakic subjects looked through the Groningen IOL Telescope type 1 (GIT1) system under different conditions. Four different IOL designs with different clinical levels of photic phenomena were evaluated by the subjects. Subjects were asked to give a subjective rating of each lens and perform a psychophysical test. The results of this study were compared to the clinical outcomes of the subjective perception of halo, glare, and starbursts of cataract patients implanted with the same IOL models. Depending on the visual test performed, a good correlation can be found between the tests performed here and the bother levels of real cataract patients. The results validate the use of this methodology to evaluate preclinical visual symptoms. The system could be a powerful tool for the design and development of new optical designs.