Multifocal intraocular lenses.

Since the publication of my last article in Current Opinion in Ophthalmology in 1991 (2:33-34), the use of multifocal intraocular lenses (IOLs) has not gained general acceptance among ophthalmologists. Despite this situation, major IOL companies have continued to invest in clinical trials of new designs. Recently, large optic multifocal lenses used mainly with extracapsular extraction provided good results, with 94% to 100% of best-corrected cases having distance correction of 20/40 vision or better; 77% to 100% similarly had J3 near vision or better, and approximately 52% to 63% of patients became eyeglass independent. Between 50% to 80% of eyes in which 20/40 vision or better was obtained and in which J2 or better resulted were unaided. However, all multifocal lens designs showed some reduction in contrast sensitivity compared with monofocal designs using Regan charts and Vistech 6500 tests. Contrast sensitivity loss was probably only significant when reading very small print or in low-contrast light. Small-incision surgery with phacoemulsification and more accurate IOL power calculations have made the goal of emmetropia more possible. Also, less eyeglass dependence with the use of multifocal IOLs is a more realistic expectation.