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Corneal Topography and Tomography Readings with Mask-Wear During the COVID-19 Pandemic

J Cataract Refract Surg. 2022 Nov 16. doi: 10.1097/j.jcrs.0000000000001090. Online ahead of print.

ABSTRACT

PURPOSE: To assess the effect of mask wear on corneal topography and tomography readings. Setting: Tertiary ophthalmic center. Design: Prospective, observational, comparative study.

METHODS: Subjects underwent imaging with the Tomey® TMS-4a topographer and the OCULUS Pentacam® HR tomographer. Imaging was performed without a mask and then testing was repeated while wearing three different masks: Halyard Level 2, Halyard Level 3 and KN95. Measurements during mask wear were compared to measurements without a mask. Kruskal-Wallis ANOVA grouped test was used to compare mean differences without vs with mask wear on measurements. Chi-square test was used to compare frequency of differences between different masks and against-the-rule versus with-the-rule astigmatism. The frequencies of clinically significant changes in axis of astigmatism, magnitude of astigmatism and mean keratometry values were calculated.

RESULTS: 52 eyes were included in the study with a mean age of 34.71. Mask wear did not show statistically significant differences in mean topography and tomography measurements compared to without mask wear for all parameters. However, the majority, 53% (83/156) had a >10 degrees and 41% (64/156) had >15 degrees change in axis of astigmatism on topography when wearing a mask compared to no mask wear.

CONCLUSIONS: Mask wear did not result in statistically significant mean changes in keratometry readings on topography and tomography. However, axis of astigmatism varied >10 degrees in the majority of patients. Axis determination should be interpreted with caution with respect to refractive surgery and/or toric intraocular lens planning in individuals whose measurements were obtained while wearing a mask.

PMID:36399667 | DOI:10.1097/j.jcrs.0000000000001090

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