Measurement of posterior corneal astigmatism by the IOLMaster 700

Session Details

Session Title: Anterior Segment Imaging I

Session Date/Time: Monday 24/09/2018 | 16:30-18:00

Paper Time: 17:09

Venue: Room A4

First Author: : B.LaHood NEW ZEALAND

Co Author(s): :    M. Goggin                    

Abstract Details

Purpose:

To provide the first description of posterior corneal astigmatism as measured by the IOLMaster 700 and assess how its characteristics compare to previous measures from other devices.

Setting:

The Ophthalmology Department of the Queen Elizabeth Hospital, The University of Adelaide and Ashford Advanced Eye Care, Adelaide, Australia

Methods:

1098 eyes had biometric measurements taken on the IOLMaster 700. These were analysed to provide magnitudes and orientation of steep and flat axes of anterior and posterior corneal astigmatism. Subgroup analysis was conducted to assess correlation of posterior corneal astigmatism characteristics to anterior corneal astigmatism as well as describe the distribution of posterior corneal astigmatism with age.

Results:

Mean posterior corneal astigmatism was 0.24D ± 0.15D. The steep axis of posterior corneal astigmatism was vertically orientated in 73.32% of measurements. Correlation between the magnitude of anterior corneal astigmatism and posterior corneal astigmatism was greatest when the steep axis of the anterior corneal astigmatism was orientated vertically (r = 0.68, p <0.0001). As age increased, vertical orientation of the steep axis of anterior corneal astigmatism became less common whereas for posterior corneal astigmatism it remained by far the most common orientation.

Conclusions:

This first description of posterior corneal astigmatism measurement by the IOLMaster 700 found the average magnitude of posterior corneal astigmatism and proportion of vertical orientation of steep axis was lower than previous estimates. The IOLMaster 700 appears capable of providing enhanced biometric measurement for individualised surgical planning.

Financial Disclosure:

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