The effect of the timing of the cessation of contact lens use on the results of biometry

Session Details

Session Title: Biometry & Quality of Vision

Session Date/Time: Tuesday 25/09/2018 | 08:00-10:30

Paper Time: 08:06

Venue: Room A2

First Author: : C.Goudie UK

Co Author(s): :    R. Davies   A. Tatham   A. Sifton   M. Wright           

Abstract Details

Purpose:

Biometry is an essential part of assessment for cataract surgery. Contact lens use is thought to alter the shape of the cornea which may lead to unreliable biometry measurements. Current guidelines vary regarding when to remove contact lenses prior to performing biometry and there is no clear evidence behind these guidelines. This study aimed to determine the effect of soft contact lens wear on biometric measurements by examining the change in predicted lens power for emmetropia at several time points following removal of soft contact lenses.

Setting:

Princess Alexandra Eye Pavilion, which is a University teaching hospital in Edinburgh, UK.

Methods:

A prospective, controlled study of healthy soft contact lens wearers. Biometry was performed immediately after removing contact lenses and then after 2,4 and 7 days of no contact lens use. Healthy non-contact lens wearers were used as controls and had biometry performed on two separate occasions. All measurements were taken with the Zeiss IOLMaster.

Results:

Fourteen subjects and 13 controls were recruited. There was no significant difference in age or gender between groups. Eight of 14 subjects wore daily disposable contact lenses, 2 wore 2-weekly and 4 wore monthly soft contact lenses. Measurements from controls and contact lens wearing subjects showed similar degrees of variation over time. The within subject standard deviation in predicted IOL power for emmetropia for contact lenses wearers was 0.20 D (95% CI 0.16 to 0.25D) compared to 0.18 D (95% CI 0.12 to 0.26 D) for controls.

Conclusions:

There is significant variation in UK practice regarding advice on when to remove contact lenses before having biometry performed. Our study suggests that soft contact lens use does not affect the results of biometry prior to cataract surgery. We conclude that soft contact lens wearers are currently being advised to remove their contact lenses for an unnecessarily long period of time prior to having biometry performed.

Financial Disclosure:

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