New method to improve the quality of vision in cataractous keratoconus eyes

Abstract

To analyze using optical simulations if the proper use of a segmented intraocular lens (IOL) can improve the visual outcomes compared to the implantation of a spherical monofocal IOL. The wavefront profile of the Mplus (Oculentis) and a monofocal IOLs with the phase transformation introduced by each IOL were calculated using a Hartmann-Shack wavefront sensor. In addition, the wavefront profile of schematic eye models of various keratoconus conditions was obtained and was propagated to the IOLs. The optical performance of such combination was obtained after combining ray tracing and Fourier optics. A pre-clinical validation was also evaluated incorporating clinical data from three different keratoconus eyes of three patients. The implantation of the Mplus IOL can compensate or reduce the overall coma of the eye with keratoconus improving the quality of vision compared with a spherical monofocal IOL due to lower displacements of the retinal image or tilting in keratoconus. All theoretical simulations were confirmed afterwards by mean of a preclinical validation. The use of a standard toric segmented IOL with a proper orientation and selection of the addition can improve the optical quality of the keratoconus eye compared to the use of a monofocal spherical IOL.

Comparison of the optical quality vision between real post-LASIK myopic laser surgery and the simulated implantation of a phakic IOL in low myopia

“…As commented above, the methodology used in this study was based on that described in a previous study in which the optical performance of three presbyopia-correcting IOLs implanted in eyes with previous laser refractive surgery was simulated and to show that the use of a standard toric segmented IOL with a proper orientation and selection of the addition can improve the optical quality of the keratoconus eye compared to the use of a monofocal spherical IOL. 12 , 13 . Following the same procedure of this previous work, an ICL of − 4.5 D was characterized in terms of wavefront aberration profile using a Hartmann-Shack sensor and based on the guidelines of the ISO 11979-9 14 , 15 .…”

“…The simulated through-focus modulation transfer function (TMTF) for three presbyopia-correcting IOLs (Mini-Well, Tecnis Symfony and Lentis Mplus) implanted in one eye with previous myopic LASIK and another one with hyperopic LASIK were obtained and compared. Recently, this methodology has been used to analyze if the proper use of a segmented intraocular lens (IOL) could improve the visual outcomes compared to the implantation of a spherical monofocal IOL 13 . As previously mentioned, the efficacy and safety of phakic IOLs implantation compared to laser surgery in high myopia has been extensively analyzed and studied.…”

Analysis and comparison of monofocal, extended depth of focus and trifocal intraocular lens profiles

“…Parameters as the as Modular Transfer Function (MTF), Point Spread Function (PSF) or Strehl ratio have been used for this purpose 2 , 5 – 8 . A combination of optical bench measurements and simulations was developed by Camps et al in order to obtain the same parameters but with the advantage of using real data patients in these simulations 5 , 6 , 9 . This new method based on the wavefront of the IOL allowed to know the light propagation through different surfaces.…”

Comparative visual outcomes of EDOF intraocular lens with FLACS vs conventional phacoemulsification

“…2,3 The decentration and tilt of the IOL is a crucial factor influencing the visual quality of patients postoperatively. 4 The architecture of the capsulorhexis has a great influence on the position of the lens, which in turn affects the refractive effect. 5 If the capsulotomy is too large, the IOL optical system might be tilted or decentered, resulting in optical aberrations and damage to the retinal image.…”