Influence Of Angle Kappa, Angle Alpha And Decentration Of Multifocal Intraocular Lens On Visual Quality After Implantation Of Multifocal Intraocular Lenses

To assesses the influence of angle kappa(κ), angle alpha(α) and decentration of postoperative multifocal intraocular lens(mIOL) on vision and objective visual quality after femtosecond-assisted cataract surgery.

Retrospective study

Nuri Eye Hospital, Daejeon, South Korea.

Seventy one eyes of 71 patients who underwent diffractive trifocal IOL implantation (Zeiss AT Lisa Trifocal 839MP) after refractive cataract surgery using femtosecond laser (LensAR, LensAR Inc., USA) were included.

The preoperative angle κ, angle α, and decentration of postoperative mIOLs (distance between the center of the IOL and the visual axis), Strehl ratio, modulation transfer function (MTF) curve, high-order aberrations (HOAs) (whole eye, cornea, intraocular) were measured before surgery and 3 months after surgery using the OPD-scan III (Nidek Inc., Japan). Distance, intermediate, and near visual acuities were recorded 3 months postoperatively. A patient questionnaire was also administered.

Angle κ, angle α, and degree of IOL deviation were 0.22mm ± 0.13 (range: 0.01 - 0.65mm), 0.38mm ± 0.2 (range: 0.07 - 1.58mm), and 0.21mm ± 0.13 (range: 0.01 - 0.70 mm), respectively. Angle κ correlated with intraocular HOA significantly (r=-0.270, p=0.023), but not correlated with Strehl ratio, MTF curve, or other HOAs. No variables that correlated with angle alpha and the degree of IOL deviation. In subgroup analysis, no difference in Strehl ratio, MTF curve, HOA of whole eye and degree of IOL deviation between the group with angle κ > 1 standard deviation (SD) (> 0.35 mm, 0.43 mm ± 0.07) and the group with angle κ < 1 SD (< 0.09 mm, 0.057 mm ± 0.02).

In femtosecond-assisted uncomplicated cataract surgery with multifocal IOL implantation, there was no difference in the deviation of the center of the IOL according to the size of preoperative angle κ and angle α, and it doesn’t seem that angle κ and angle α affect the objective visual quality.