Trace elements imbalance of the scleral shell of the eye in various forms of glaucoma
Authors:   Eye center “East Sight Recovery” LLC, Moscow, Russia, Arutyunyan L.L. ,   Russian Medical Academy of Continuing Professional Education, Moscow, Russia, Iomdina E.N. ,   Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia, Morozova Y.S. ,   Eye center “East Sight Recovery” LLC, Moscow, Russia,   Russian Medical Academy of Continuing Professional Education, Moscow, Russia, Anisimova S.Y. ,   Eye center “East Sight Recovery” LLC, Moscow, Russia, Anisimov S.I. ,   Eye center “East Sight Recovery” LLC, Moscow, Russia,   A.I. Yevdokimov Moscow State University of Medicine and Dentristy, Moscow, Russia
Published: June 2022

Purpose. To conduct a comparative study of the trace elements balance in scleral biopsies of patients with various clinical forms of glaucoma. Material and methods. The content of trace elements was determined in scleral biopsies of 16 patients with primary open-angle glaucoma (POAG), 13 patients with normal tension glaucoma (NTG) and 15 patients with pseudoexfoliative glaucoma (PEG). The mean age of the patients was 79.5 ± 2.5 years. As a control, fragments of the sclera of 14 cadaveric eyes without a history of glaucoma were used. The concentration of K, Mg, Ca, Fe was estimated using inductively coupled plasma atomic emission spectrometry (ICP-AES, Agilent ICP-AES 720 ES, USA), to determine the level of Zn, Cu, Al, Mn inductively coupled plasma mass spectrometry (ICP-MS, Bruker ICP-MS 820, Germany) was used. Results. A statistically significant shift in the balance of Cu / Zn compared with the control was found in all forms of glaucoma: NTG (p = 0.008), PEG (p = 0.006), POAG (p = 0.03), while there are differences between NTG and POAG in this indicator not detected (p = 0.609), but with PEG the difference was significant (p = 0.0001). The Cu/Fe ratio in the glaucoma eye sclera samples also significantly differed from the control both in NTG (p = 0.009) and PEG (p = 0.006) and in POAG (p = 0.006). This parameter in patients with POAG significantly differed from the corresponding parameter in the group with NTG (p = 0.0001) and PEG (p = 0.016). A shift in the balance of Mn/Cu compared with the control was detected only in the sclera of patients with NTG (p = 0.0064), there were no corresponding differences with the control in PEG (p = 0.157) and POAG (p = 0.773), but a significant difference was found between the group NTG and POAG (p = 0.0001). The balance of Mn/Fe in comparison with the control group was disturbed in all forms of glaucoma: NTG (p = 0.0066), PEG (p = 0.00034), POAG (p = 0.0027). At the same time, in patients with NTG and PEG, the balance of Mn / Fe differed significantly from this indicator in POAG (p = 0.078 and p = 0.0485, respectively). The most pronounced imbalance of Mg/Ca compared with the control was characterized by the sclera of patients with PEG (p = 0.01) and POAG (p = 0.0254). Conclusion. In all studied forms of glaucoma in the sclera, disturbances in the ratio of Cu / Zn, Cu / Fe, Mn / Cu, Mn / Fe and Mg / Ca of varying severity were revealed in comparison with the sclera of eyes without glaucoma. Differences in the indicated ratios in NTG, POAG and PEG have also been established, which may determine the features in the pathogenesis and clinical course of these forms of glaucoma lesions. Keywords: primary open-angle glaucoma; normal tension glaucoma; pseudoexfoliative glaucoma, biomechanics of the corneoscleral membrane of the eye; trace element ratio.