Effect of posterior corneal astigmatism on surgical outcomes of toric intraocular lens implantation in eyes with oblique corneal astigmatism

Session Details

Session Title: Presented Poster Session: Toric Lenses & IOL Power Calculation

Venue: Poster Village: Pod 1

First Author: : S.Nakano JAPAN

Co Author(s): :    T. Hiraoka   T. Oshika                    

Abstract Details

Purpose:

There have been many reports regarding the importance of posterior corneal astigmatism in surgical outcomes of toric intraocular lens (T-IOL) implantation. It is also known that the influence of posterior corneal astigmatism on whole corneal astigmatism is different between types of astigmatism. The aim of this study was to compare surgical outcomes after T-IOL implantation in eyes with oblique corneal astigmatism between two preoperative calculation methods of T-IOL power and axis based on keratometry (anterior corneal evaluation only) and anterior segment optical coherent topography (AS-OCT) (anterior + posterior corneal evaluation).

Setting:

Ryugasaki Saiseikai Hospital, Ibaraki, JAPAN

Methods:

Thirty-nine eyes of 38 subjects with oblique corneal astigmatism undergoing T-IOL implantation were included. With an online calculator program, T-IOLs were selected based on keratometric data and implanted in 26 eyes (KRT group), whereas those were selected based on AS-OCT measurements (anterior + posterior astigmatism) and implanted in 13eyes (AS-OCT group). All surgeries were performed by a single surgeon with a same method. Visual acuity, refraction, and keratometry were measured preoperatively and 3 month postoperatively.

Results:

The logMAR uncorrected visual acuities in the KRT and AS-OCT groups were 0.15 ± 0.23 (mean ± standard deviation) and 0.05 ± 0.18, respectively. The logMAR best-corrected visual acuities were -0.02 ± 0.10 and -0.08 ± 0.00, respectively. There were no significant differences in both uncorrected and best-corrected visual acuities between groups (p > 0.05). Postoperative subjective astigmatisms in the KRT and AS-OCT groups were -0.51 ± 0.57 D and -0.25 ± 0.37 D, and postoperative objective astigmatisms were -0.73 ± 0.81D and -0.94 ± 0.35 D, respectively, showing no significant differences between groups (p > 0.05).

Conclusions:

Preoperative T-IOL selection method based on both anterior and posterior corneal measurements did not improve surgical outcomes compared to standard selection method based on keratometric data in this study. The influence of posterior corneal astigmatism on whole corneal astigmatism may be smaller in eyes with oblique astigmatism than with other types of astigmatism.

Financial Disclosure:

None