An Update on Corneal Biomechanics and Architecture in Diabetes.
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ABSTRACT:
SUBMITTER: Del Buey MA
PROVIDER: S-EPMC6589322 | biostudies-other | 2019
REPOSITORIES: biostudies-other
Publications
An Update on Corneal Biomechanics and Architecture in Diabetes.
Del Buey María A MA Casas Paula P Caramello Constanza C López Nuria N de la Rica Marisa M Subirón Ana B AB Lanchares Elena E Huerva Valentín V Grzybowski Andrzej A Ascaso Francisco J FJ
Journal of ophthalmology 20190602
In the last decade, we have witnessed substantial progress in our understanding of corneal biomechanics and architecture. It is well known that diabetes is a systemic metabolic disease that causes chronic progressive damage in the main organs of the human body, including the eyeball. Although the main and most widely recognized ocular effect of diabetes is on the retina, the structure of the cornea (the outermost and transparent tissue of the eye) can also be affected by the poor glycemic contro ...[more]
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Project description:PurposeTo evaluate the changes of corneal biomechanics in granular, lattice and macular corneal dystrophy (GCD, LCD and MCD), and to assess the agreement of intraocular pressure (IOP) between Corvis ST tonometer (CST) and Goldmann applanation tonometer (GAT) and the agreement of central corneal thickness (CCT) between CST and ultrasound pachymeter (USP) in patients with corneal dystrophy.MethodsFifty-nine eyes with corneal dystrophy (26 eyes with GCD, 18 eyes with LCD and 15 eyes with MCD) and 48 eyes from healthy subjects were included in this study. All subjects received ocular examination and anterior segment photography under slit-lamp microscope. Corneal biomechanical parameters were obtained using CST. IOP and CCT were obtained using GAT and USP, respectively. Mixed-effects models were fitted for group comparisons and Bland-Altman analyses were applied for assessing the agreement of IOP or CCT between devices.ResultsGCD, LCD and MCD showed higher First Applanation Deformation Amplitude (A1DA) and Corvis Biomechanical Index (CBI), and a lower Stiffness Parameter at First Applanation (SPA1), compared to controls. After CCT adjustment, MCD group showed a higher A1DA compared to GCD or LCD. The IOP measured by CST demonstrated an overestimated bias to the one obtained by GAT in all groups. The CCT measured by CST and USP showed good agreement in healthy eyes but not in those with corneal dystrophy.ConclusionCorneal biomechanical alterations were observed in GCD, LCD and MCD. IOP and CCT measured by CST should be interpreted carefully in eyes with corneal dystrophy.
| S-EPMC9905605 | biostudies-literature
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Project description: Not available
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Project description:PurposeSmoking may influence measured IOP through an effect on corneal biomechanics, but it is unclear whether this factor translates into an increased risk for glaucoma. This study aimed to examine the association of cigarette smoking with corneal biomechanical properties and glaucoma-related traits, and to probe potential causal effects using Mendelian randomization (MR).MethodsCross-sectional analyses within the UK Biobank (UKB) and Canadian Longitudinal Study on Aging (CLSA) cohorts. Multivariable linear and logistic regression models were used to assess associations of smoking (status, intensity, and duration) with corneal hysteresis (CH), corneal resistance factor, IOP, inner retinal thicknesses, and glaucoma. Two-sample MR analyses were performed.ResultsOverall, 68,738 UKB (mean age, 56.7 years; 54.7% women) and 22 845 CLSA (mean age, 62.7 years; 49.1% women) participants were included. Compared with nonsmokers, smokers had a higher CH (UKB, +0.48 mm Hg; CLSA, +0.57 mm Hg; P < 0.001) and corneal resistance factor (UKB, +0.47 mm Hg; CLSA, +0.60 mm Hg; P < 0.001) with evidence of a dose-response effect in both studies. Differential associations with Goldmann-correlated IOP (UKB, +0.25 mm Hg; CLSA, +0.36 mm Hg; P < 0.001) and corneal-compensated IOP (UKB, -0.28 mm Hg; CLSA, -0.32 mm Hg; P ≤ 0.001) were observed. Smoking was not associated with inner retinal thicknesses or glaucoma status in either study. MR provided evidence for a causal effect of smoking on corneal biomechanics, especially higher CH.ConclusionsCigarette smoking seems to increase corneal biomechanical resistance to deformation, but there was little evidence to support a relationship with glaucoma. This outcome may result in an artefactual association with measured IOP and could account for discordant results with glaucoma in previous epidemiological studies.
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