Evaluation For Optical Performance Of Trifocal Intraocular Lenses Using Optical Bench System

The optical performance of two trifocal intraocular lenses (IOLs) with the same optical design but different materials were compared. 

Optical bench system was used to evaluate modulation transfer function (MTF) and the effect of halos on modulation transfer function (MTF) of two trifocal IOLs.

The optical performance of two trifocal IOLs with the same optical design but different materials were compared. The two trifocal IOLs (Relatively high [IOL A] and low [IOL B] water content IOLs) have identical optic design except for water content and material of IOL. MTF and effect of halos on MTF of two trifocal IOLs were analyzed using optical bench system. Using both white and green light as light sources, optical images of each trifocal IOL were obtained with United States Air Force targets at far, intermediate, and near distances, and then MTF value was calculated. Simulated headlight images were obtained, and dysphotopsia of each trifocal IOL caused by white and green light were also evaluated.

At 17.6 cycles/degree, two trifocal IOLs showed good and stable image quality from far to intermediate distance. IOL A was found better image quality at near distance than IOL B. MTF of the two trifocal IOLs were higher under the green light source than under the white light source. Under the green light source, the MTF values ​​of both trifocal IOLs showed similar image quality, but under the white light source, IOL A showed higher MTF than IOL B at near distance. In the far-focused image, the degree of light blur of the two trifocal IOLs was equivalent.

Although the change in water content due to the difference in IOL material did not affect the optical performance of the trifocal IOL, the trifocal IOL with relatively high-water content showed higher optical performance than the trifocal IOL with relatively low-water content.