[Characteristics and analysis of corneal astigmatism in age-related cataract patients over 50 years old]

Efficacy of Toric Intraocular Lens Implantation in Patients Older Than 80 Years with Cataracts and Corneal Astigmatism

INTRODUCTION

This study analyzed the visual outcome following cataract surgery with toric intraocular lenses (IOLs) in patients older than 80 years with corneal astigmatism.

METHODS

A total of 159 patients (159 eyes) older than 80 years with corneal astigmatism (≥ 0.75 D) were included. Fifty-three eyes received Acrysof IQ® toric IOLs (SN6AT2-5), while the others received non-toric IOLs: 51 eyes received Acrysof IQ® IOLs (SN60WF) and 55 eyes received A1-UV IOLs. The uncorrected distance visual acuity, corrected distance visual acuity, and refraction (spherical equivalent, refractive cylinder) were assessed at 3 months postoperatively. The prediction error of refractive outcome and percentages of eyes within ± 0.50 D and ± 1.00 D in the toric IOL group obtained using five toric IOL formulas (Barrett predicted posterior corneal astigmatism (PCA), Barrett measured PCA, Kane, EVO 2.0 and Næser-Savini) were compared.

RESULTS

At 3 months postoperatively, the average uncorrected distance visual acuity was better in the toric IOL group than the non-toric IOL group (p < 0.001). The mean residual refractive cylinder was lower in the toric IOL group than the non-toric IOL group (p < 0.001). The Næser-Savini formula achieved the lowest mean absolute error (0.39 D) and had the highest percentages of eyes within an absolute error of 0.50 D and 1.00 D (72% and 98%) compared to the other formulas.

CONCLUSION

The results demonstrate the efficacy of toric IOL implantation in patients older than 80 years with corneal astigmatism and provide strong evidence for cataract surgeons to encourage such patients to choose toric IOLs.

The Influence of Angle Alpha, Angle Kappa, and Optical Aberrations on Visual Outcomes after the Implantation of a High-Addition Trifocal IOL

The aim of our investigation was to examine the possible correlations between optical aberrations, angle kappa, angle alpha, and visual outcomes following cataract surgery. In total, 56 eyes of 28 patients were implanted with the Liberty 677MY trifocal intraocular lens (IOL). Pre- and postoperative higher-order aberrations, coma, astigmatism, angle alpha, and angle kappa were registered, along with uncorrected and corrected visual acuities at multiple distances. Visual acuity and contrast sensitivity defocus curves were plotted, and the areas under the curve were calculated 1 and 3 months postoperatively. Excellent visual outcomes were found at all distances. Patients reported low levels of dysphotopsia, and 96.4% of patients achieved complete spectacle independence. While angle kappa significantly decreased during cataract surgery (p = 0.0007), angle alpha remained unchanged (p = 0.5158). Angle alpha correlated with postoperative HOAs and had a negative impact on near vision (p = 0.0543). Preoperative corneal HOA and coma had a strong adverse effect on future intermediate and near vision. Residual astigmatism significantly affected postoperative intermediate vision (p = 0.0091). Our results suggest that angle kappa is not an optimal predictive factor for future visual outcomes, while angle alpha and the preoperative screening of optical aberrations might help patient selection prior to multifocal IOL implantation.