Two bifocals and a trifocal
Reviewed by Amit Patel

The authors compare the optical outcomes of two bifocal intraocular lenses (AcrySof ReSTOR +2.50 Diopter [D] add +3.0D add) with a trifocal lens (AT LISA tri 839MP). The optical qualities of the lenses were quantified by measuring the modulation transfer function (MTF) at five different focal points (0D, -1.5D, -2.0D, -2.5D and -3.0D) and four apertures (2.0mm, 3.0mm, 3.75mm and 4.5mm). At far distance (0D), the bifocal +2.0D lens performed best, at -2.5D and -3.0D, the bifocal +3.0D add lens performed best and the trifocal provided best MTF values at -1.5D. All three lenses had a similar performance at -2.0D. As expected the trifocal lens showed less aperture (pupil) dependence than the bifocal lenses. As an experimental study, the authors acknowledge that the results are obtained for an ideal lens centration and in vivo outcomes may differ due to tilt and decentration.

Optical quality differences between three multifocal intraocular lenses: bifocal low add, bifocal moderate add, and trifocal.
Madrid-Costa D, Ruiz-Alcocer J, Ferrer-Blasco T, et al.
JOURNAL OF REFRACTIVE SURGERY
2013;29(11):749-54.