Blue-light-absorbing lenses and their effect on scotopic vision

PURPOSE: To correct assumptions about material transmission and provide a more realistic assessment of the optical properties of intraocular lenses (IOLs) made from AcrySof Natural material (Alcon). SETTING: University of Arizona Department of Ophthalmology, Tucson, Arizona, USA. METHODS: The transmission characteristics of conventional and AcrySof Natural IOL materials immersed in a balanced salt solution were examined to determine the differences in scotopic vision. The removal of the crystalline lens during cataract surgery and its effect on scotopic vision were also analyzed. RESULTS: When only considering the IOL properties, the AcrySof Natural lens decreased light entering the eye under scotopic by 14.6%, much lower than previously reported. Furthermore, when removal of the crystalline lens was taken into consideration, the AcrySof Natural material actually increased the amount of light entering the eye by 52% under these same conditions. CONCLUSIONS: Previous discrepancies in the transmission characteristics of IOL materials have led to an underestimation of the performance of the AcrySof Natural material under scotopic conditions. Accounting for both transmission and the crystalline lens demonstrates an increase in light levels entering the eye with the AcrySof Natural material when compared to young phakic subjects.