Prediction accuracy after toric intraocular lens implantation using several corneal astigmatism evaluation methods

Session Details

Session Title: Pseudophakic IOLs: Toric

Session Date/Time: Tuesday 10/10/2017 | 08:30-10:30

Paper Time: 09:12

Venue: Room 4.4

First Author: : W.Park SOUTH KOREA

Co Author(s): :    M. Kim   E. Kim   N. Kang              

Abstract Details

Purpose:

To evaluate difference of residual astigmatisms and estimated astigmatism using corneal astigmatism evaluation methods after toric intraocular lens implantation. This study is designed to find out the most accurate corneal astigmatism evaluation method for toric intraocular lens implantation.

Setting:

Department of Ophthalmology, Bucheon St. Mary’s hospital, College of Medicine, Catholic University of Korea, Seoul, Korea

Methods:

A total of 43 eyes of 40 patients who underwent cataract surgery with toric intraocular lens implantation were included retrospectively. Preoperative keratometric values were obtained with (1) auto Keratometer (RK-F1®, Canon, Japan), (2) total corneal astigmatism considering posterior astigmatism, (3) true net power astigmatism, and (4) Holladay equivalent K-reading astigmatism (3mm) using rotating Scheimpflug camera (Pentacam®: Oculus, Wetzlar, Germany). At 2 months after toric intraocular lens implantation, we compared the difference between residual astigmatism and estimated astigmatism using pre-operative keratometric value obtained by those 4 methods.

Results:

Mean difference between residual astigmatism and estimated astigmatism using total corneal astigmatism (0.54±0.37) was significant lower than auto-keratometric astigmatism (0.98±1.08), true net power astigmatism (0.80±0.99), and Holladay EKR astigmatism (0.71±1.04) (p<0.05). The percentages of correct astigmatic predictions (residual – estimated astigmatism) within ±0.50D in the total corneal astigmatism were the highest (89.5%, 70.6%, 75.3%, and 77.8%, respectively) of all methods.

Conclusions:

Total corneal astigmatism considering posterior astigmatism is the most predictable corneal astigmatism evaluation method for toric IOL calculation. Therefore, we should consider not only anterior corneal astigmatism but also posterior corneal astigmatism to reduce postoperative astigmatism after toric IOL implantation.

Financial Disclosure:

NONE