Clinical classification schemes are never static. As new knowledge accumulates — whether in pathogenesis, diagnostic improvements, novel treatment approaches, monitoring, or rehabilitation — there arises a need to refine the logical principles underlying classification.
Nearly half a century has passed since the adoption of the current classification of primary open-angle glaucoma proposed by A.P. Nesterov and A.Ya. Bunin. During this time, significant advancements have been made: new insights into the pathogenesis of primary glaucoma have emerged, in vivo morphological assessment of certain structures has become possible, enhancing diagnostic capabilities; and new terminological constructs have appeared, requiring well-founded interpretation or serving as grounds for scientific discussion. These developments provide a basis for substantive revisions to the existing classification.
The primary focus of this discussion is a clinical subtype of primary open-angle glaucoma — normal (low-) tension glaucoma. This article is dedicated to its reconsideration.

PURPOSE. To study endothelin-1 (ET-1) levels in tear fluid of patients with primary open-angle glaucoma (POAG) in relation to age, disease stage, and intraocular pressure (IOP).
METHODS. ET-1 levels in tear fluid were measured using enzyme-linked immunosorbent assay (ELISA) in 10 healthy volunteers and 61 patients with POAG (stages I–IV). The analysis was performed with Synergy MX photometer using ELISA Kit for Endothelin-1.
RESULTS. The normal ET-1 level in tear fluid was 8.57± 5.84 pg/ml. In POAG, ET-1 levels were 10.42±3.59 pg/ml at stage I, 28.70±6.11 pg/ml at stage II, 14.28±4.71 pg/ml at stage III, and 10.8±6.50 pg/ml at stage IV. After intensification of hypotensive treatment, IOP decreased from 18.55± 5.95 mm Hg to 13.27 mm Hg, correlating with a reduction in ET-1 levels from 22.83±4.82 to 12.31±2.49 pg/ml.
CONCLUSION. ET-1 is a significant systemic vasoconstrictor factor playing a key role in the pathogenesis of glaucomatous optic neuropathy. Moderate-stage glaucoma is characterized by a marked increase in ET-1 levels, which may serve as a prognostic marker. Intensified hypotensive therapy, associated with IOP reduction, correlates with a decrease in ET-1 levels.

PURPOSE. To study the effect of age on the development of involutional changes in the retina.
METHODS. The influence of the age factor on the development of degree I–II retinopathy (RP) was studied on the basis of a 6-year prospective observation of a natural cohort of 7959 initially healthy male members of locomotive crews (LCMs) aged 18–66 years old. A four-field 2×2 table and a multivariate regression model were used to evaluate the relative risk (RR) of each year of life as an independent pathogenic factor. Statistical analysis was performed using Statistica 6.0.
RESULTS. Comparative analysis revealed an association between RP I–II and the ages of 26, 28–30, 32, 34, 35, and 37 years. In multivariate analysis, ages 18–38 were not identified as statistically significant for RP I–II. The ages of 26–46 years did not demonstrate a significant RR. Additionally, the ages of 38, 42, 45, and 59 years did not show significant RR values and were not selected as predictors associated with the development of RP I–II in multivariate analysis.
CONCLUSION. The statistical heterogeneity of chronological age as an independent risk factor may be linked to specific age-related characteristics and the unique influence of each life period on aging processes and RP I–II progression. Further research is required to explore the age-related risk factor using alternative statistical approaches to clarify its unique characteristics and role in retinal damage in RP I–II development.

PURPOSE. To evaluate preliminary outcomes of PreserFlo^® drainage system implantation for glaucoma treatment in terms of safety and efficacy.
METHODS. In this open prospective study, 9 patients (9 eyes), including 7 men and 2 women, diagnosed with primary open-angle glaucoma were examined and underwent surgery. All patients underwent implantation of the PreserFlo^® drainage system. The average age of the patients was 74.1±11.3 (59–89) years. Standard ophthalmological examinations were performed preoperatively and at 1 day, 7 days, 1 month, and up to 5 months postoperatively. The maximum follow-up period was 5 months.
RESULTS. No intraoperative complications were observed in the early or late postoperative periods. One patient underwent needling of the filtration bleb postoperatively.
A pronounced hypotensive effect was noted in all patients one week after surgery, which persisted in seven out of nine patients for up to two months. Two patients experienced a gradual increase in intraocular pressure (IOP) to 20–23 mm Hg, necessitating additional topical hypotensive therapy. All patients exhibited an improvement in both corrected and uncorrected visual acuity at the longest follow-up. Given the severity of the patients' conditions (multiple previous surgeries and maximal medical therapy), surgical outcomes were categorized as "complete success" and "relative success."
CONCLUSION. This study presents the first short-term (up to 5 months) analysis of the outcomes of PreserFlo^® drainage device implantation in patients with primary open-angle glaucoma in the Russian Federation. Preliminary findings indicate that the device is both effective and safe. Further studies with a larger patient cohort are required to assess long-term outcomes.

PURPOSE. To refine the technique of filtering bleb (FB) plasty using allografts in an experimental model on laboratory animals, evaluate the histomorphological outcomes, and assess the efficacy and safety of plastic reconstruction of cystic FBs in the clinical setting.
METHODS. Steroid-induced glaucoma was modeled in 30 rabbits (30 eyes), followed by an anti-glaucoma procedure with allogeneic sponge drainage. Ninety days post-operatively, a conjunctival defect was created in the FB area and covered with an allogeneic biomaterial derived from fascial sheaths for conjunctival reconstruction.
In cases of cystic FBs, revision was performed with dissection of sclero-conjunctival adhesions. The allograft was placed over the scleral flap in the filtration area, shaped, and secured to the surrounding sclera. The Tenon’s capsule and conjunctiva were then positioned over the biomaterial and anchored to the limbus.
RESULTS. A moderately diffuse FB was observed in the early postoperative period following conjunctivoplasty. The allogeneic biomaterial was visualized under the conjunctiva in the filtration area, adjacent to the eye globe. Over time, a connective tissue regenerate, structurally similar to the underlying bed, formed at the site of the allograft. Histomorphological studies confirmed that the stages of allograft replacement with newly formed tissue were a natural result of the transplantation process.
In FB revisions, sclero-conjunctival adhesions were dissected, and the allograft for conjunctival reconstruction was placed over the scleral flap, shaped, and secured with 8/0 interrupted sutures. Ultrasound biomicroscopy was performed to examine the topography of ocular surface structures in the long-term follow-up period after conjunctival reconstruction.
CONCLUSION. The developed technique for conjunctivoplasty in cystic FBs using allografts is a safe and reliable method for reinforcing ocular surface tissues involved in FB formation. This approach provides therapeutic, functional, and cosmetic benefits.

PURPOSE. To investigate changes in macular thickness in patients with cataract and primary open-angle glaucoma (POAG) receiving prostaglandin analogues (PGA) during the perioperative period of phacoemulsification (PE), based on optical coherence tomography (OCT) data.
METHODS. The study included 80 patients (126 eyes) divided into four groups: the control group (group 1) without POAG, and three POAG groups receiving different therapies: group 2 — tafluprost 0.0015% (Taflotan); group 3 — a fixed combination of brinzolamide 1% and timolol maleate 0.5% (Azarga); group 4 — Taflotan and Azarga. Macular thickness was assessed using OCT preoperatively, on postoperative day 7, and at 1 and 3 months in the central, superior, inferior, nasal, and temporal sectors. Statistical analysis was performed using nonparametric methods, including Pearson's χ² test, the Kruskal–Wallis H-test, and Fisher's F-test.
RESULTS. One month postoperatively, the proportion of patients without pathological macular thickening exceeded 88% in all groups: 88.2% (group 1), 94.6% (group 2), 100% (group 3), and 90% (group 4) (p>0.05).
At 3 months, retinal thickness remained above normal in two cases in group 1, two cases in group 2, none in group 3, and one case in group 4.
CONCLUSION. The use of Taflotan during the perioperative period of PE in patients with cataract and POAG did not increase the risk of cystoid macular edema compared to the control and comparison groups.

PURPOSE. Monitoring of a patient with a rare combined pathology of juvenile open-angle glaucoma (JOAG) and Best disease (Best vitelliform macular dystrophy, BVMD).
METHODS. Visometry, autorefractometry, tonometry, gonioscopy, biomicroscopy, ophthalmoscopy, ocular ultrasound, digital fundus photography, optical coherence tomography angiography (OCT-A).
RESULTS. A 32-year-old male patient reported a long-standing fog before his right eye, a spot, progressive visual impairment in both eyes (more pronounced in the right eye), eye redness, and poor tolerance to hypotensive eye drops. He was previously diagnosed with Best disease and JOAG in both eyes. Fundus photography and OCT-A revealed retinal changes characteristic of JOAG. The patient exhibited poor tolerance to topical glaucoma medications, experiencing significant conjunctival hyperemia and ocular pain. A well-tolerated antiglaucoma regimen was established, consisting of a fixed combination of bimatoprost 0.3 mg/ml and timolol 5 mg/ml (BIMOKKO-SZ); dorzolamide 20 mg/ml (Dorzolamide-SZ); and brimonidine 2 mg/ml (Brimonidine-SZ) (all manufactured by NAO Severnaya Zvezda, Russia). Vision, intraocular pressure, and OCT-A parameters stabilized.
During the follow-up, retinal thickening exceeding 700 µm was observed, with a risk of inner retinal layer rupture and macular hole formation. Emergence of new choroidal vessels and active choroidal neovascularization were oserved. Intravitreal aflibercept injection was administered, resulting in disease stabilization.
CONCLUSION. The combination of JOAG and Best disease requires personalized monitoring and treatment selection, including conservative, laser, surgical, and antiangiogenic therapies as needed. Patient follow-up is ongoing.

Hypotensive drops that penetrate into the aqueous humor of the anterior chamber cause thinning, roughness, irregularities, and microcracks in the anterior lens capsule, followed by the formation of microfibrils and pseudomembranes. In a five-year follow-up of 2532 glaucoma patients, nuclear cataract progression due to prolonged use of hypotensive eye drops was identified in 592 cases (23.4%).
Patients with glaucoma exhibit a lower oxygen consumption rate by the lens (2.27 femtomoles/min/cell vs. a normal value of 2.83 femtomoles/min/cell), reduced oxygen utilization for adenosine triphosphate (ATP) production (0.72 femtomoles/min/cell vs. a normal value of 0.932 femtomoles/min/cell), and decreased maximal respiratory capacity of lens cells (4.17 vs. 5.46 femtomoles/min/cell). These changes represent risk factors for cataract development.
In uveal glaucoma, blood proteins and inflammatory cells accumulate in the aqueous humor, posterior synechiae form between the iris and the anterior lens capsule, and fibrinous exudate develops in the pupillary area. Patients with uveal glaucoma receive anti-inflammatory and hypotensive pharmacotherapy, as well as laser and surgical treatments, including drainage device implantation. These factors contribute to a 34% increase in the incidence and progression of cataracts in uveal glaucoma patients.