The role of morphometric and biomechanical parameters of the cornea in glaucoma monitoring

Purpose: to study the role of morphometric and biomechanical parameters of the cornea in the diagnosis and monitoring of glaucoma.

Materials and methods. A total of 463 eyes of patient aged 17 to 94 years were analyzed: 18 healthy, without glaucoma, without PEX of the older age group — 91, without glaucoma with PEX — 33, young myopic — 30, with POAG — 69, with primary open-angle pseudoexfoliation glaucoma (PXG) — 81, with normal tension glaucoma (NTG) — 60, with pigment dispersion syndrome — 62, with juvenile glaucoma (JG) — 19. In case of glaucoma, it was compensated. IOP was studied taking into account the biomechanical properties of the fibrous membrane of the eye (bIOP), DA Ratio, Integr. Radius (IR), SP-A1, SSI.

Results. There is a relationship between the central corneal thickness (CCT) and the development of glaucoma (r = –0.244, p = 0.000), IOP level measured by standard non-contact tonometry (r = 0.301, p = 0.000). It was found a decrease of CCT (r = –0.205, p = 0.000) and bIOP (r = –0.111, p = 0.012) with age. DA Ratio and Integr. Radius are associated with bIOP (r = -0.647 and r = –0.652, respectively, p = 0.000) and with CCT (r = -0.449 and r = –0.456, respectively, p = 0.000). DA Ratio decreases with patient aging (r = 0.108, p = 0.016), but IR does not change (p = 0.208). SP-A1 increases with increasing bIOP level (r = 0.481, p = 0.000), is higher with “thick” corneas (r = 0.421, p = 0.000). The SSI index is related to the axial length of the eye and decreases as it increases (r = –0.441, p = 0.000), is higher in “thick” corneas (r = 0.142, p = 0.001), and this index also increases with age (r = 0.516, p = 0.000).

Conclusions. CCT is an independent risk factor for glaucoma development, undergoes changes with age and development of glaucomatous damage. Corneal rigidity indicators are important to evaluate dynamically to determine the achievement of tolerant IOP.

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27. Patent No. 2823133 C1 Russian Federation, IPC A61B 5/00, A61F 9/00. Method for predicting the risk of developing normal-tension glaucoma: No. 2023134091: declared 12/18/2023: published 07/18/2024 / A.V. Malyshev, A.S. Apostolova, A.A. Sergienko [et al.]; applicant Federal State Budgetary Educational Institution of Higher Education “Maikop State Technological University”. — EDN SVYJUM.