ESCRS - PP10.11 - Relevance Of Measured Posterior Corneal Astigmatism In Post Laser Iol Calculations

Relevance Of Measured Posterior Corneal Astigmatism In Post Laser Iol Calculations

Published 2024 - 42nd Congress of the ESCRS

Reference: PP10.11 | Type: Free paper | DOI: 10.82333/hk2e-sh97

Authors: Bjørn Gjerdrum* 1 , Kjell Gunnar Gundersen 1

1Ifocus Eyeclinic,HAUGESUND,Norway

Purpose

To compare the accuracy of astigmatism predictions in IOL planning after previous laser vision correction (LVC) using predicted and measured posterior corneal astgmatism

Setting

The study includes results from two private eye clinics situated in Haugesund and Stavanger in Norway

Methods

This was a retrospective study of successful cataract surgery or refractive lens exchange In post LVC patients. Preoperative biometry was performed with two different biometers: One SS-OCT biometer (Anterion, Heidelberg Engineering) and one combined reflection and SS-OCT biometer, (Eyestar 900, Haag-Streit). Calculations were performed with both devices using the built-in Barrett Toric calculator using predicted posterior corneal astigmatism (PPA). For one device (Anterion), measured posterior corneal astigmatism (MPA) was also used. The astigmatism prediction error (APE) was calculated as the magnitude of the vector differences between the achieved and the predicted refractive astigmatism. 

 

Results

The study included 32 eyes of 32 patients. The mean age was 62 years and 47% were female. Toric IOL´s were implanted in 53% of the eyes. Mean Follow-up time was 98 days (58 - 24). The mean uncorrected VA was 0.1 on the logMAR scale. The mean postoperative refractive spherical equivalent and astigmatism was -0.07 and -0,34, respectively. The mean APE was 0.48 D, 0.45 D, and 0.44 D for the Eyestar PPA, Anterion PPA and Anterion MPA, respectively. The percentages of eyes with APE within 0.5 D was 62, 66 and 72  for the Eyestar PPA, Anterion PPA and Anterion MPA, respectively.

No statistically significant differences of means (p>0.4) or percentages of eyes within 0.5, 0.75 or 1 D of APE (p>0.6)were observed.

Conclusions

Including measured posterior astigmatism did not give statistically significant improvement in predicting postoperative refractive astigmatism in post post laser IOL calculations.