Posters

Comparison of four toric intraocular lens calculators using power vector analysis

Poster Details

First Author: M.Hirasawa JAPAN

Co Author(s):    K. Minami   Y. Ohta   S. Ooki   A. Takahashi   H. Bissen-Miyajima        

Abstract Details

Purpose:

The retrospective case series compared astigmatic prediction errors with the use of 4 toric intraocular lens (IOL) calculators.

Setting:

Department of Ophthalmology, Tokyo Dental College Suidobashi Hospital, Tokyo, Japan

Methods:

Eighteen eyes of 13 patients who received multifocal toric IOL (SND1T3-6, Alcon) and postoperative axis misalignments of less than 10 degrees were included in this study. The difference between predicted manifest astigmatisms following the implantation of selected toric model and postoperative manifest astigmatisms were compared with 4 different toric IOL calculators; a conventional calculators without corrections of effective lens position and posterior corneal astigmatism (calculation A), Holladay (calculation B) , Barrett (calculation C), and Barrett toric calculator available on APACRS web (calculation D). The difference was analyzed with the J0 and J45 components of the power vectors.

Results:

For preoperative astigmatisms, 17 eyes were with-the-rule and 1 eye was against-the-rule. Mean postoperative manifest astigmatism was 0.26 ± 0.31 D. Differences in J0 components were -0.37±0.23 D (A), -0.44±0.24 D (B), -0.03±0.28 D (C), and -0.04±0.27 D (D), while those in J45 were 0.11±0.33 D, 0.12±0.36 D, 0.09±0.28 D, and 0.09±0.2 D, respectively. Difference in J0 components with calculation C and D were significantly smaller than that with A and B (P<0.001: Scheffé's multiple comparison. There were no differences in J45 components.

Conclusions:

Differences in the conventional and Holladay-corrected calculations demonstrated the influence of the posterior corneal astigmatism, while astigmatism was corrected in Barrett-based calculators.

Financial Disclosure:

None