Features of biomechanics of the cornea, IOP and parameters of the eye anterior segment in primary glaucoma in the indigenous inhabitants of the Republic of Sakha (Yakutia)

The study of the biomechanical properties of the cornea in patients of different ethnic groups with primary glaucoma is very relevant and determines a personalized approach to the management and treatment of these patients. The purpose of the work is to study the biomechanical properties of the cornea and the parameters of the anterior segment of the eyes in patients with primary glaucoma of the indigenous inhabitants of the Republic of Sakha (Yakutia). Materials and methods. A total of 220 eyes of 112 native residents of the Republic of Sakha (Yakutia) aged 65.79 ± 4.98 years were examined, including 72 eyes with primary angle-closure glaucoma (PACG), 70 eyes with primary open-angle glaucoma (POAG) stages II–III, and 78 eyes with incomplete age-related cataracts without glaucoma. Corneal topographic parameters were measured using a Pentacam corneotopographer (Oculus). Intraocular pressure (IOP), corrected IOP (bIOP), biomechanical parameters including stress-strain index (SSI), and applanation stiffness parameter (SP-A1) were determined using a Corvis ST analyzer (Oculus, Germany). Results. A “thin” central corneal thickness (CCT) was found in individuals without glaucoma and in patients with POAG, but biomechanical parameters indicated increased corneal stiffness: patients with POAG had higher SP-A1 and bIOP values. Patients with PACG had a “normal” CCT, and biomechanical parameters indicated a more elastic cornea compared to individuals without glaucoma and POAG, which is probably a protective mechanism in people with a shallow anterior chamber from a potential increase in IOP. High SSI values were found in all three groups, which is related to the patients’ age. However, the SSI in the POAG group was lower than in the other groups, likely due to therapy with prostaglandin analogues, which reduce the stiffness of the eye fibrous layer. Conclusion. The identified differences in the parameters of the eye anterior segment and corneal biomechanics in patients with various forms of glaucoma will improve the effectiveness of dynamic monitoring and treatment.

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