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bioRxiv · 10.1101/569772

Impact of pterygium on the ocular surface and meibomian glands

Wanzeler, A.·Barbosa, I. A. F.·Duarte, B.·Barbosa, E. B.·Borges, D. A.·Alves, M.
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Abstract

PurposeTo analyze how ocular surface parameters correlate to pterygium and investigate the possible impact on tear film and meibomian glands.\n\nMethodswe investigated objective parameters of the ocular surface such as conjunctival hyperemia, tear film stability and volume, meibomian gland dysfunction, dry eye disease, corneal topography comparing healthy individuals and correlating with the pterygium clinical presentation.\n\nResultsA total of 83 patients were included. Corneal astigmatism induction was 2.65 {+/-} 2.52 D (0.4-11.8). The impact of pterygium on the ocular surface parameters compared to matched controls was seen in: conjunctival hyperemia (control 1.55{+/-}0.39/pterygium 2.14{+/-}0.69; p=0.0001), tear meniscus height (control 0.24{+/-}0.05 mm/pterygium 0.36{+/-}0.14mm; p 0.0002), meiboscore lower eyelid (control 0.29{+/-}0.64/pterygium 1.38{+/-}0.95; p 0.0001) and meiboscore upper eyelid (control 0.53{+/-}0.62/pterygium 0.98{+/-}0.75; p=0.0083). We found a high number of pterygium patients (88%) presented meibomian gland alterations. Interestingly, meibomian gland loss was coincident to the localization of the pterygium in 54% of the upper and 77% lower lids.\n\nConclusionPterygium greatly impacts on ocular surface by inducing direct alterations in the pattern of meibomian glands besides corneal irregularities, conjunctival hyperemia and lacrimal film alterations, inducing significant symptoms and potential signs of dysfunction.

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Wanzeler, A., Barbosa, I. A. F., Duarte, B., Barbosa, E. B., Borges, D. A., Alves, M.. 2019-03-06. Impact of pterygium on the ocular surface and meibomian glands. https://doi.org/10.1101/569772

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