Clinical Analysis of Macular Choroidal Thickness in Pseudoexfoliative Glaucoma and Primary Open-Angle Glaucoma

Purpose. To evaluate the differences in macular choroidal thickness and volume among patients with pseudoexfoliative glaucoma (PXG), patients with primary open-angle glaucoma (POAG), and controls. Methods. A total of 50 PXG patients (50 eyes) and 56 POAG patients (56 eyes) were selected as the PXG group and the POAG group, respectively, in this case-control study. A total of 54 age-, gender-, IOP-, and axial length-matched healthy individuals (54 eyes) were selected as the control group. Enhanced-depth imaging-optical coherence tomography (EDI-OCT) was used to measure and analyze the choroidal thicknesses and volumes in 9 macular regions of all subjects. Results. The choroidal thicknesses in the central subfield (CSM), temporal inner macula (TIM), inferior inner macula (IIM), and temporal outer macula (TOM) and the mean macular choroidal thickness were significantly thinner in the PXG group than in the control group (all P < 0.05 ). The choroidal volumes in the TIM, IIM, and TOM and the mean macular choroidal volume were significantly smaller in the PXG group than in the control group (all P < 0.05 ). The choroidal thicknesses in the CSM and IIM and the mean macular choroidal thickness were significantly thinner in the PXG group than in the POAG group (all P < 0.05 ). The choroidal volumes in the IIM and TOM and the mean macular choroidal volume were significantly smaller in the PXG group than in the POAG group (all P < 0.05 ). Multivariable linear regression analysis showed that the mean macular choroidal thickness was significantly thinner in association with older subjects and longer axial length eyes. There was no association between the macular choroidal thickness of various macular regions and visual field mean defect (MD) in groups PXG and POAG (all P > 0.05 ). Conclusions. The macular choroidal thicknesses and volumes (inferior and temporal) in PXG patients were thinner and smaller than those in POAG patients and healthy individuals. The role of choroidal thickness changes in the course of PXG remains unclear. A future prospective study is needed to better define these changes in PXG patients.

Success Rate in Micropulse Diode Laser Treatment in Regards to the Phakic Versus Non-phakic Status, as Well as Refractive Errors and Glaucoma Subtypes

Purpose. To evaluate the efficiency of micropulse transscleral cyclophotocoagulation (MP-TSCPC) considering different characteristics: lens status, spherical equivalent (SE), and glaucoma sub-types. Methods. A retrospective case-series study was designed to evaluate intraocular pressure (IOP), and the number of IOP lowering medications, used by glaucoma patients treated with MP-TSCPC between 2016 and 2019. Cases had a follow-up period of 12 months and 24 months. Achieving an IOP reduction higher than 20%, or the decrease of at least one IOP lowering medication, was considered a successful outcome. The same population was analyzed by classifying them in three groups according to certain characteristics: lens status, refractive errors (calculated according to their SE), glaucoma sub-types. Results. A total of 86 eyes were included. In most cases, IOP and IOP lowering medications were decreased with a statistically significant difference (P<0.0001), and all of them had a successful outcome. The percentage of IOP drop oscillated between 15.5% (open angle glaucoma sub-groups), and 41.5% (pseudoexfoliative glaucoma sub-groups), 24 months after surgery. The Person’s coefficient obtained was low for the SE and IOP association, at both the 12 and the 24-month postoperative mark (-0.009 and 0.08, respectively). Conclusions. The MP-TSCPC treatment was successful in decreasing IOP and IOP lowering medications, with similar efficacy between phakic and pseudophakic eyes. The higher effect was observed in the pseudoexfoliative glaucoma. No association was found between the SE and the IOP drop after MS-TSCPC treatment.

Retinal Nerve Fibre Layer and Ophthalmic Artery Blood Parameters in Pseudoexfoliation Syndrome and Pseudoexfoliative Glaucoma

PurposeThis study investigates the relationship between ophthalmic artery blood flow parameters and retinal nerve fiber layer (RNFL) thickness in eyes with pseudoexfoliation. MethodsThree comparisons were made in this study. In the first, eyes without glaucoma with pseudoexfoliation in any of the eyes were compared with the control group. In the second, eyes with pseudoexfoliation and without glaucoma were compared with those with pseudoexfoliation and glaucoma. In the third, cases with glaucoma and pseudoexfoliation were compared with the control group. Ophthalmic artery colour Doppler imaging measurements were performed in all patients. Also, peripapillary RNFL analysis was performed. ResultsA statistically significant difference was found between the total RNFL measurements according to group (p = 0.012; p < 0.05). From the paired comparisons, the total RNFL measurements from the control group were higher than the group without glaucoma (p = 0.010). No statistically significant difference was found between the total RNFL measurements of the other groups (p > 0.05). In the pseudoexfoliative glaucoma (PXG) group, there was a statistically significant negative correlation between total RNLF and Peak systolic velocity (PSV) (r = -0.743; p < 0.01). There was also a statistically significant negative correlation between total RNLF and End diastolic velocity (EDV) (r = -0.691; p < 0.01). There was no significant relationship between total RNLF and resistive index (RI) measurements (p > 0.05). ConclusionPseudoexfoliation syndrome(PXS) caused a decrease in the PSV and EDV values of ophthalmic artery blood flow parameters. Again, PXS caused a decrease in total RNFL, RNFL S, RNFL I and RNFL T thickness values.

Micropulse transscleral cyclophotocoagulation: clinical outcomes of treatment of early stages open-angle glaucoma

Purpose. To evaluate treatment efficiency of open-angle glaucoma with micropulse transscleral cyclophotocoagulation, to determine the optimal total energy of laser exposure and to assess the stability of the glaucoma process after treatment. Material and methods. A prospective study was carried out. It included 34 (21 patients) with primary open-angle and pseudoexfoliative glaucoma of stages 1-3, which undergone micropulse transscleral cyclophotocoagulation. The patients were divided into subgroups 1 and 2, depending on the total amount of laser energy (100 J and 150 J, respectively). At different periods of observation, the intraocular pressure, best corrected visual acuity, visual fields, cup-to-disc ratio and the number of antiglaucoma drugs were determined. Results. In the general group, all operated patients achieved a decrease in IOP to a tolerant level, from a median value of 27 [25; 28] in the preoperative period, up to 17.5 [15; 20] at the end of the observation period. The number of used drugs decreased statistically significantly, from 3.0 [3.0; 3.0] to 2.0 [1.0; 2.0]. There was a statistically significant increase in the mean deviation of the retinal photosensitivity, from –4.85 [–8.25; –2.17] to –4.36 [–7.06; –2.37] after 18 months. Indicators of best corrected visual acuity and CDR remained stable throughout the observation period. In subgroup 2 (150J), a statistically more significant decrease in IOP level (p=0.033) and the number of used drugs (p=0.001) was achieved compared with subgroup 1 (100J). Conclusion. Micropulse transscleral cyclophotocoagulation is an effective and safe method of treating open-angle glaucoma in patients with early stages of the disease and high values of best corrected visual acuity. Using a total amount of energy in 150J contributes to a more pronounced decrease in IOP and a decrease in the number of applied drugs than an energy in 100J. Key words: open-angle glaucoma, pseudoexfoliative glaucoma, micropulse cyclophotocoagulation.

PSEUDOEXFOLIATIVE SYNDROME AS A TRIGGER FOR PSEUDOEXFOLIATIVE GLAUCOMA

Glaucoma is one of the leading causes of blindness and disability worldwide. Pseudoexfoliative glaucoma is known to be the most aggressive and difficult-to-treat form of secondary glaucoma. According to the literature, pseudoexfoliative glaucoma occurs in 25-30% of cases among all open-angle glaucoma. The recent studies have established that a quarter of patients with pseudoexfoliative glaucoma are blind in one eye, and 7% are blind in both eyes. Risk factors for glaucoma include systemic and ophthalmic factors, one of which is the development of pseudoexfoliative syndrome. In patients with pseudoexfoliative syndrome, glaucoma occurs 20 times more often than in the general population of the same age. The purpose of this research is to study the informativeness of individual phenomena of pseudoexfoliative syndrome (PES) in order to improve early diagnosis and prevention of pseudoexfoliative glaucoma. The study included 114 patients diagnosed as having PES. Exclusion criteria were as follows: age up to 45 years, surgery on the eyeball, a history of disease (iridocyclitis, uveitis, corneal pathology, and traumatic eye disease), pigment dispersion syndrome. Along with the standard set of diagnostic measures, patients underwent biomicroscopy in the conditions of maximum drug-induced mydriasis, gonioscopic examination; the proportion of patients was examined by optical coherence tomography (SD-OCT Topson 3D oct-2000FA Plus (version 7/21/003/0)). The study revealed signs of pseudoexfoliative syndrome (deposition of pseudoexfoliative material on various structures of the anterior segment of the eye) in 100% of cases. Higher values of intraocular pressure (from 29 to 34 mm Hg) were found in the patients with elements of blocking the angle of the anterior chamber (narrowing or closing the angle, increased pigmentation and the presence of draining exfoliative conglomerates). The optical coherence tomography study revealed a thinning of the retinal nerve fibres (33.60 ± 0.43 μm), a significant thinning of retinal nerve fibre layer in patients with pseudoexfoliative syndrome and even more significant thinning in 29 patients diagnosed with pseudoexfoliative glaucoma. Thus, we can conclude knowing the microsymptoms of the disease, mandatory investigating the conditions of the maximum drug-induced mydriasis can contribute to detect pseudoexfoliative syndrome even in the initial stages and thus to prevent the development of pseudoexfoliative glaucoma.

Study of the prevalence and the structural features of pseudoexfoliative glaucoma

Purpose. To analyze the prevalence of pseudoexfoliative glaucoma (PEG) and to determine the structural markers of impaired intraocular fluid outflow (IOF) in the sclera. Materials and methods. There were analyzed the case histories of 7603 patients with primary open-angle glaucoma (POAG), including pseudoexfoliative glaucoma (PEG), aged 50 to 86 years, who applied to The Novosibirsk branch of S.N. Fedorov' NMRC «MNTK «Eye Microsurgery» of Minzdrav of Russia from 2011 to 2016. In 43 patients with PEG (43 eyes, average age 67±17 years), who were first treated with surgical treatment (non-penetrating deep sclerectomy and those who agreed to participate in the scientific study, a comprehensive histological analysis of the scleral flaps was performed. Results. PEG was diagnosed in 3981 cases (60.8%). The predominance of advanced stages – moderate and advanced-is due to the referral of patients for consultation and surgical treatment in a highly specialized institution. In the majority of patients, the histological examination of scleral flaps revealed markers of an increased risk of fibrosis of the artificial transcleral outflow pathways of the IOF: an increase in the number and biosynthetic activity of matrix-producing cells. Conclusions. PEG occupies a leading position in the structure of POAG among patients of The Novosibirsk branch of S.N. Fedorov' NMRC «MNTK «Eye Microsurgery». Histological examination of the scleral flaps of patients with PEG revealed markers of an increased risk of fibrosis of the artificial transcleral outflow pathways of the IOF. Key words: pseudoexfoliative glaucoma, fibrosis, NSE.