Search

Purpose: a comparative study of the elemental composition of scleral biopsy specimens from patients with various clinical forms of glaucoma. Material and methods. 44 patients aged 79.5 ± 2.5 were divided into three groups depending on the form of glaucoma: 16 patients with primary open-angle glaucoma (POAG) (group 1); 13 patients with normal tension glaucoma (NTG) (group 2); 15 patients with pseudoexfoliative glaucoma (PEG) (group 3). For elemental analysis, we used scleral biopsies obtained during planned surgical treatment of glaucoma (non-penetrating sinus trabeculectomy). Scleral fragments of 14 donor eyes with no history of glaucoma served as controls. The concentration of macroelements K, Mg, Ca, and Fe was determined using inductively coupled plasma atomic emission spectrometry (ICP-AES, Agilent ICP-AES 720 ES, USA), while microelement concentration (Zn, Cu, Al, Mn) was measured using inductively coupled plasma mass spectrometry (ICP-MS, Bruker ICP-M S 820, Germany). Results. In all forms of glaucoma, scleral samples showed a varying increase in the content of such elements as Zn, Fe, Mg, AL, Ca, K. The highest content of Zn and Fe was found in the scleral tissue of patients with NTG, the difference with the control (p = 0.0001 andp = 0.0003) and with POAG (p = 0.0002, p = 0.0001) being highly significant. The difference between the content of Zn in scleral biopsies of patients with POAG and PEG was also statistically significant (p = 0.0002), whilst no significant difference in Fe content in the sclera (p = 0.69) was found between POAG and PEG Higher Mg concentrations as compared to the control were found in NTG (p = 0.00014) and POAG (p = 0.00002).Patients with POAG (p = 0.0005) and PEG (p = 0.00022) showed the highest accumulation of Ca in the sclera. No differences were found in Mg content of scleral biopsies between patients with NTG and POAG (p = 1.0), while the level of Ca in POAG (p = 0.02) and PEG (p = 0.00001) was significantly higher than in NTG. A significantly lower content of Cu was found in the sclera samples of patients with NTG (p = 0.022), POAG (p = 0.004) and PEG (p = 0.00004) as compared to the control, as well as a reduced content of Mn in POAG (p = 0.00003) and PEG (p = 0.0012). Contrarywise, NTG patients showed an increased content of Mn (p = 0.000003). No differences were found in the Cu content between the sclera of patients with NTG and POAG (p = 0.47), while Cu level in PEG was significantly lower than in POAG (p = 0.034) and NTG (p = 0.013). Conclusion. The macro- and microelement imbalance of the sclera of the eyes with different forms of glaucoma indicates differences in their pathogenesis. This can be the reason for the different severity of disorders of collagen biosynthesis and the formation of cross-links in the connective tissue structures of the sclera, as well as the varying degree changes in the hydrodynamics of the intraocular fluid, which on the whole can affect the level of intraocular pressure and the pattern of glaucoma development.

Purpose. To compare the thickness of the prelaminar layer of nerve fibers and the depth of the lamina cribrosa in patients with diverse forms of open-angle glaucoma, measured by optical coherence tomography (OCT).Material and methods. 130 patients aged 71.4 ± 9.7 with stage II (advanced) glaucoma were divided into three groups depending on the form of glaucoma: group 1 of 39 patients with primary openangle glaucoma (POAG); group 2 of 26 patients with normal-tension glaucoma (NTG); group 3 of 22 patients with pseudoexfoliative glaucoma (PEG). The control group consisted of 43 patients without ophthalmic pathology. All patients were scanned for the optic disc and the macular areas in the OCT Disk + Macula 3D regimen and in the Disk Raster regimen (Optopol Revo 60 OCT device (Optopol Technology, Poland). The depth of the lamina cribrosa (LC) and the thickness of the prelaminar layer of nerve fibers (tPLNF) were calculated.Results. No significant differences were found between the LC depth in patients with different forms of glaucoma compared with the control group. LC depth averaged 426.9 ± 98.7 μm (p < 0.164) in patients with POAG, 416.9 ± 161.0 μm (p < 0.818) with NTG and 425.5 ± 88.04 μm, (p < 0.18) with PEG. The thinnest layer of prelaminar nerve fibers was found in patients with NTG (134,0 ± 91.4 μM), where the value was half as much as the control (p < 0.001). There were no differences in the tPNFL parameter in POAG (193.2 ± 114.6 μm) and PEG (190.7 ± 115.3 μm) but both were significantly lower as compared to the control group (p < 0.001, p < 0.002) respectively.Conclusion. The study of LC parameters contributes to a better understanding of the pathogenesis of optic neuropathy in diverse forms of glaucoma. It opens up new opportunities in the differential diagnosis and prediction of the glaucoma course.

The results of comparative studies of the structural and biomechanical features of the corneoscleral eye shell in various clinical forms of glaucoma are presented. The article discusses how the systemic and local imbalance of trace elements that regulate collagen biosynthesis, the formation of cross-links in the connective tissue structures of the sclera, and the hydrodynamics of the intraocular fluid, affect the intraocular pressure level, and thereby the character of the development of glaucomatous lesions in normal tension glaucoma. Modern literature is shown to indicate the prospects for further research in this direction.