Influence of angle Kappa on the optimal intraocular orientation of asymmetric multifocal intraocular lenses

  1. Sergio Bonaque 1
  2. Matt T. Jaskulski 2
  3. David Carmona Ballester 3
  4. Alicia Cristina Pareja Ríos 4
  5. J.M. Trujillo Sevilla 1
  1. 1 Wooptix S.L. San Cristobal de La Laguna, Santa Cruz de Tenerife, Spain
  2. 2 Universidad de Murcia
    info

    Universidad de Murcia

    Murcia, España

    ROR https://ror.org/03p3aeb86

  3. 3 Universidad de La Laguna
    info

    Universidad de La Laguna

    San Cristobal de La Laguna, España

    ROR https://ror.org/01r9z8p25

  4. 4 Hospital Universitario de Canarias
    info

    Hospital Universitario de Canarias

    San Cristóbal de La Laguna, España

    ROR https://ror.org/05qndj312

Journal:
Journal of Optometry: peer-reviewed Journal of the Spanish General Council of Optometry

ISSN: 1888-4296

Year of publication: 2021

Volume: 14

Issue: 1

Pages: 78-85

Type: Article

DOI: 10.1016/j.optom.2020.07.004 DIALNET GOOGLE SCHOLAR lock_openOpen access editor

Abstract

Purpose to evaluate the effects of kappa angle and intraocular orientation on the theoretical performance of asymmetric multifocal intraocular lenses (MIOL). Methods For a total of 21 corneal aberrations, a computational analysis simulated the implantation of a computationally designed MIOL. An image quality parameter (IQ) (visually modulated transfer function metric) was calculated for a 5.0-mm pupil and for three conditions: distance, intermediate, and near vision. The procedure was repeated for each eye after a rotation of the MIOL with respect to the cornea from 0º to 360º in 5º steps. Kappa angles from 0 to 900 microns, in 150 microns steps, combined with two two variants of MIOL centration were tested: in the corneal apex or in the center of the entrance pupil. A p-value ≤ 0.05 was considered significant. Results There were statistically significant differences of the IQ depending of the intraocular orientation of the MIOL. If kappa angle was increased, there was a statistically significant decrease of the IQ. The IQ maintained stable when the optimal intraocular orientation was re-calculated for each kappa angle. In general, the inter-variability of the results between subjects was very high. There were no strong evidences supporting that there exists a preferable centration point. Conclusions Our results suggest that kappa angle theoretically affects significantly the performance of asymmetric MIOL implantation. However, its negative effect can be compensated if a customized intraocular orientation is calculated taking into account the presence of the kappa angle.