Progression Of Primary Open-angle Glaucoma Research Articles

The impact of different forms of exercise on intraocular pressure, blood flow, and the risk for primary open angle glaucoma.

Primary open angle glaucoma (POAG) is a chronic disease characterized by progressive optic nerve damage and irreversible loss of vision, often diagnosed at late stages. Elevated intraocular pressure (IOP) is the major risk factor for its onset and progression while older age, myopia, genetic factors, blood pressure (BP), and reduced ocular blood flow (OBF) have also been linked to the disease. Different forms of exercise are known to have significant, but variable, effects on IOP, BP, ocular perfusion pressure (OPP), OBF and oxygen metabolism, and ultimately the risk for development and progression of POAG. While population-based studies lack agreement regarding the relationship between exercise and POAG status, data suggests that resistance training causes a short-term increase in IOP, BP, and OPP. Conversely, aerobic exercise has been shown to cause a short-term decrease in IOP and increase in BP and OPP. Research also suggests that following an exercise program over an extended period may lead to a long-term decrease in IOP, however its cessation results in a prompt return to baseline levels. Data suggests normal vascular autoregulation ensures minimal change in OBF following extended exercise unless OPP rises ∼70% above baseline. Although exercise may alter IOP, BP, and OBF, both acutely and chronically, it is currently uncertain if physical activity significantly alters risk for the onset and progression of POAG.

Exploring the Relation Between Peripapillary Retinal Vessel Caliber and Visual Field Defects in Primary Open-Angle Glaucoma.

Background Primary open-angle glaucoma (POAG) is a progressive optic neuropathy characterized by loss of retinal ganglion cells, optic nerve head changes, and visual field defects. Vascular factors, alongside intraocular pressure, play a crucial role in POAG pathogenesis, and this study aims to explore the relationship between retinal vessel caliber and visual field defects in POAG patients. Purpose To evaluate the association between retinal vessel calibers in the peripapillary area with visual field defects in one or both hemifields. Materials and Methods This cross-sectional study was conducted at a tertiary eye care center in northern Karnataka for one year, enrolling 100 eyes from 50 primary open-angle glaucoma (POAG) patients with visual field abnormalities. Fundus color stereoscopic photographs were taken using a Canon digital camera, and diameters of the superior and inferior temporal arteries (STA and ITA) and veins (STV and ITV) in the peripapillary area were measured. Visual field defects were categorized, and statistical analyses were performed to correlate retinal vessel calibers with field defect locations. Results Participants had a mean age of 89.68 years, with 72% male. Visual field defects included superior arcuate scotoma (20%), inferior arcuate scotoma (32%), double arcuate scotoma (30%), and tubular vision (18%). Significant vessel caliber changes were observed: for superior hemifield defects, the mean STA: ITA ratio was 1.15 (p = 0.001), and for inferior defects, it was 0.94 (p = 0.04). STV: ITV ratios also showed significant changes corresponding to visual field defects. Eyes with defects in both hemifields showed pronounced narrowing, particularly in inferotemporal vessels. Conclusions Decreased retinal vessel caliber is significantly associated with visual field defects in primary open-angle glaucoma and can be a valuable diagnostic parameter tool for assessing glaucomatous damage and the progression and severity of POAG.

Effects of Stress and Strain on the Optic Nerve Head on the Progression of Glaucoma.

In primary open-angle glaucoma, the rate of retinal nerve fiber layer thickness decrease was negatively correlated with lamina cribrosa strain, which was associated with intraocular pressure and optic nerve head geometric factors. We hypothesized that the biomechanical deformation of the optic nerve head (ONH) contributes to the progression of primary open-angle glaucoma (POAG). This study investigated the biomechanical stress and strain on the ONH in patients with POAG using computer simulations based on finite element analysis (FEA) and analyzed its association with disease progression. We conducted a retrospective analysis that included patients diagnosed with early-to-moderate stage POAG. The strains and stresses on the retinal nerve fiber layer (RNFL) surface, prelaminar region, and lamina cribrosa (LC) were calculated using computer simulations based on FEA. The correlations between the rate of RNFL thickness decrease and biomechanical stress and strain were investigated in both the progression and non-progression groups. The study included 71 and 47 patients in the progression and non-progression groups, respectively. In the progression group, the factors exhibiting negative correlations with the RNFL thickness decrease rate included the maximum and mean strain on the LC. In multivariate analysis, the mean strain on the LC was associated with optic disc radius, optic cup deepening, axial length, and mean intraocular pressure (IOP), whereas the maximum strain was only associated with mean IOP. In early-to-moderate stage POAG, the rate of RNFL thickness decrease was influenced by both the mean and maximum strain on the LC. Strains on the LC were associated with mean IOP, optic disc radius, axial length, and optic cup deepening. These results suggest that not only IOP but also ONH geometric factors are important in the progression of glaucoma.

Assessment of the correction of neuroretinal changes using 2-ethyl-6-methyl-3-hydroxypyridinium N-acetyltaurinate in the modeling of POAG

Introduction: Elevated intraocular pressure (IOP) has been identified as a major risk factor for the progression of primary open-angle glaucoma (POAG). However, the continued progression of POAG in some patients, despite the successful IOP reduction, indicates that IOP-independent mechanisms contribute to the development of optical neuropathy. Thus, it is relevant to further determine the molecular mechanisms of retinal ganglion cells (RGCs) death in order to develop therapeutic approaches independent of IOP in order to stop the progression of the disease. The aim: to research the correction possibility of experimental POAG induced by intracameral (i.c.)administration of hyaluronic acid using 2-ethyl-6-methyl-3-hydroxypyridinium N-acetyltaurinate. Materials and Methods: The study of the correction of neuroretinal changes on a model of POAG was carried out on Wistar rats. In order to correct POAG, 2-ethyl-6-methyl-3-hydroxypyridinium N-acetyltaurinate (EHMP-NAT) was used at doses of 27.5 mg/kg intramuscularly (i.m.) and 0.5 mg/kg instillationally. Further, the effectiveness of the combination of timolol eye drops with i.m. EHMP-NAT was studied. The effectiveness of the studied agents was evaluated on the 67th day of the experiment using ophthalmoscopic semi-quantitative assessment of the fundus condition, ocular tonometry, estimation of oxidative stress markers and markers involved in retinal apoptosis pathway using enzyme-linked immunosorbent assay (ELISA). Results: On the model of POAG, it was shown that 2-ethyl-6-methyl-3-hydroxypyridinium N-acetyltaurinate with the laboratory code EHMP-NAT has a pronounced neuro-, retinoprotectiveaction based on the data of ophthalmoscopy, semi-quantitative assessment of the fundus condition, ocular tonometry, estimation of oxidative stress markers (GSH, CAT, SOD) and markers involved in retinal apoptosis (BAX, BCL-2, Caspase-3). On the 67th day of the experiment, the results of a comprehensive analysis revealed that the combination of EHMP-NAT 27.5 mg/kg i.m. + timolol 0.04 mg/kg instillationally has a more pronounced protective effect than EHMP-NAT 27.5 mg/kg i.m. in monotherapy in the POAG model. Conclusion: The data obtained indicate the need for the combined use of drugs with a hypotensive effect to normalize IOP with neuroretinoprotective agents in the correction of POAG.

Risk Factors for Progression of Primary Open-Angle Glaucoma with Lower Normal Intraocular Pressure

Introduction: This study aimed to investigate intraocular pressure (IOP)-independent factors associated with the progression of primary open-angle glaucoma (POAG) with IOP ≤15 mm Hg. Methods: POAG patients with maximum IOP ≤15 mm Hg at the Kyoto University Hospital between January 2011 and August 2021 were retrospectively enrolled. We evaluated effects of various factors on the rate of mean deviation (MD) changes in the visual field (VF) examinations using a linear mixed model. These factors included hypertension, diabetes mellitus (DM), hyperlipidemia (HL), cardiovascular disease, arrhythmia, disc hemorrhage, sleep apnea syndrome, orthopedic diseases, and malignant tumors. Results: In total, 98 eyes from 68 patients were included. The baseline MD was −9.74 ± 7.85 dB. The mean rate of MD change and IOP during the observation period were −0.28 ± 0.04 dB/year and 11.8 ± 1.0 mm Hg, respectively. Comorbidity of DM or HL showed a significant positive association with the rate of MD change (β = 0.35, p = 0.0006 and β = 0.18, p = 0.036, respectively) in the model adjusted for age, sex, axial length, mean IOP, and standard deviation of IOP during the observation period. However, no significant association of DM or HL was found after adjusting for central corneal thickness. Conclusion: This study suggests that DM or HL is associated with VF deterioration in glaucoma with lower IOP, but the association may be due to differences in IOP characteristics.

Crocin supplementation in primary open angle glaucoma: A randomized, triple-blind, placebo-controlled clinical trial

PurposeGlaucoma is the leading cause of irreversible visual loss in the world. The present study was designed to evaluate the beneficial effects of crocin, as a supplement, in the management of primary open-angle glaucoma (POAG). MethodsIn total, 50 POAG patients within the age range of 30–71 years with intraocular pressure (IOP) between 12 and 21 mmHg were entered into the study, and ultimately, 40 patients (49 eyes) finished the clinical trial. The participants were randomly divided into crocin and placebo groups. Patients in the crocin group received a 15 mg crocin tablet per day for four months while others, in the placebo group, received a placebo tablet per day for four months besides the main medications during the study. After four months, all patients underwent a two-month washout period. The IOP level and optical coherence tomography of the retinal nerve fiber layer (RNFL), cup-to-disc ratio (CDR), and the best-corrected visual acuity (BCVA), as the secondary outcomes, were measured at baseline, as well as four and six months later. ResultsThe IOP value decreased significantly in the crocin group after four (P = 0.0001) and six months (P = 0.003). The difference in CDR changes after four and six months was significant between the two groups (P = 0.00009). The crocin and placebo groups did not have a statistically significant difference regarding the changes in BCVA values and RNFL thickness (P = 0.092); however, the optical coherence tomography results showed stable conditions in the retinal nerve fiber layer. ConclusionThis study indicated that administration of crocin, as a potent neuroprotective and antioxidant ingredient of saffron, could be useful as a supplement for the prevention of the POAG progression.

Identification and validation of autophagy-related genes in primary open-angle glaucoma

BackgroundAs the most common type of glaucoma, the etiology of primary open-angle glaucoma (POAG) has not been unified. Autophagy may affect the occurrence and development of POAG, while the specific mechanism and target need to be further explored.MethodsThe GSE27276 dataset from the Gene Expression Omnibus (GEO) database and the autophagy gene set from the GeneCards database were selected to screen differentially expressed autophagy-related genes (DEARGs) of POAG. Hub DEARGs were selected by constructing protein-protein interaction (PPI) networks and utilizing GSE138125 dataset. Subsequently, immune cell infiltration analysis, genome-wide association study (GWAS) analysis, gene set enrichment analysis (GSEA) and other analyses were performed on the hub genes. Eventually, animal experiments were performed to verify the mRNA levels of the hub genes by quantitative real time polymerase chain reaction (qRT-PCR).ResultsA total of 67 DEARGs and 2 hub DEARGs, HSPA8 and RPL15, were selected. The hub genes were closely related to the level of immune cell infiltration. GWAS analysis confirmed that the causative regions of the 2 hub genes in glaucoma were on chromosome 11 and chromosome 3, respectively. GSEA illustrated that pathways enriched for highly expressed HSPA8 and RPL15 contained immunity, autophagy, gene expression and energy metabolism-related pathways. qRT-PCR confirmed that the expression of Hspa8 and Rpl15 in the rat POAG model was consistent with the results of bioinformatics analysis.ConclusionsThis study indicated that HSPA8 and RPL15 may affect the progression of POAG by regulating autophagy and provided new ideas for the pathogenesis and treatment of POAG.

Relative Flow Index as a Novel Optical Coherence Tomography Angiography Biomarker in Primary Open Angle Glaucoma.

Relative flow indices as novel optical coherence tomography angiography (OCTA) biomarkers demonstrated reduced optic nerve head and peripapillary large vessel and capillary perfusion in primary open angle glaucoma (POAG). Large vessel perfusion correlated with disease severity and progression. To introduce relative flow indices as novel OCTA biomarkers and their pathologic insights in POAG. This is a retrospective case-control study where 57 POAG and 57 control eyes were included. OCTA 4.5×4.5mm optic nerve head (ONH) were analyzed using ImageJ 1.53t to calculate global flow indices (GFIs) and relative flow indices (RFIs) for whole image optic nerve head, isolated radial peripapillary capillary plexus, and isolated large vessel angiograms. Retinal nerve fiber layer thickness (RNFLT), ONH vascular density (VD), except inside disc and large vessel VD, GFIs, and RFIs were lower in POAG than control. There was a positive correlation between RNFLT and both VD and GFIs. Among RFIs, only large vessel RFI (ONHLVRFI) demonstrated a positive correlation with average RNFLT. Linear regression demonstrated a significant positive coefficient for ONHLVRFI with RNFLT as the dependent variable. The area under receiver operating characteristic curve showed diagnostic accuracy ranging fair, good, and excellent for all biomarkers. Inferior RNFLT had the highest area under the curve (0.922) while optic nerve head large vessel density had the lowest (0.523). POAG showed structural loss of RNFL neurovascular unit manifesting as positively correlated reduction of VD and RNFLT. Also, POAG had lower global perfusion of the optic nerve head and peripapillary area, resulting in the positively correlated reduction of GFIs and RNFLT. Although RFIs were lower in POAG, only ONHLVRFI demonstrated a positive correlation and regression with RNFLT, implying that large vessel hypoperfusion was associated with POAG severity and progression.

Altered stability of dynamic brain functional architecture in primary open-angle glaucoma: a surface-based resting-state fMRI study.

Delineating the neuropathological characteristics of primary open-angle glaucoma (POAG) is critical for understanding its pathophysiology. While temporal stability represents a crucial aspect of the brain's functional architecture, the specific patterns underlying its contribution to POAG remain unclear. This study aims to analyze the brain functional abnormalities in POAG using functional stability, a dynamic functional connectivity (DFC) approach based on resting-state functional magnetic resonance imaging (rs-fMRI). Seventy patients with POAG and forty-five healthy controls underwent rs-fMRI and ophthalmological examinations. The stability of DFC was calculated as the concordance of DFC over time using a sliding-window approach, and the differences in stability between the two groups were compared. Subsequently, Spearman's correlation analyses were conducted to examine the relationship between functional stability and clinical indicators. Compared with healthy controls, patients with POAG exhibited significantly decreased functional stability in the visual network, including the early visual center, ventral and dorsal stream visual cortex in both hemispheres. Conversely, stability values increased in the bilateral inferior parietal gyrus and right inferior frontal cortex. In POAG patients, the dynamic stability of the left early visual cortex and ventral stream visual cortex correlated with the mean deviation of visual field defects (r = 0.251, p = 0.037). The evidence from this study suggests that functional stability may provide a new understanding of brain alterations in the progression of POAG.

Specific features of impaired tolerance to antihypertensive treatment in patients with primary open-angle glaucoma and a hereditary history of the disease

This review considers possible reasons for the decrease in the effectiveness of antihypertensive treatment in primary open-angle glaucoma (POAG) patients with a family history of the disease, presents clinical practice examples of the effectiveness and duration of antiglaucoma topical therapy and the mechanisms and manifestations of tachyphylaxis and tolerance disorders in such patients. Clinical features and the nature of POAG progression in patients with a hereditary predisposition may be reflected in the early decrease in the effectiveness of antihypertensive treatment. In some recent publications the authors proved a more aggressive course of POAG in patients with a family history of the disease, but despite that, such works at the moment are very limited in number and unsystematized. This, in turn, prevents drawing unambiguous conclusions regarding the features of the prescribed antihypertensive therapy. The article also discusses modern aspects of pharmacogenetics in patients with POAG, its further development will help minimize unwanted side effects as well as increase the effectiveness of antihypertensive drug treatment. The results of the work presented in this review allow systematization of the available data on impaired tolerance to antihypertensive therapy and maintain the need of further clinical research in this area.

Six-Year Incidence and Risk Factors for Primary Open-Angle Glaucoma and Ocular Hypertension: The Singapore Epidemiology of Eye Diseases Study

To determine the incidence and risk factors for primary open-angle glaucoma (POAG) and ocular hypertension (OHT) in a multiethnic Asian population. Population-based cohort study. The Singapore Epidemiology of Eye Diseases study included 10 033 participants in the baseline examination between 2004 and 2011. Of those, 6762 (response rate= 78.8%) participated in the 6-year follow-up visit between 2011 and2017. Standardized examination and investigations were performed, including slit lamp biomicroscopy, intraocular pressure (IOP) measurement, pachymetry, gonioscopy, optic disc examination and static automated perimetry. Glaucoma was defined according to a combination of clinical evaluation, ocular imaging (fundus photo, visual field, and OCT) and criteria given by International Society of Geographical and Epidemiological Ophthalmology. OHT was defined on the basis of elevated IOP over the upper limit of normal; i.e., 20.4 mmHg, 21.5 mmHg, and 22.6 mmHg for the Chinese, Indian, and Malay cohort respectively, without glaucomatous optic disc change. Incidence of POAG, OHT, and OHT progression. The overall 6-year age-adjusted incidences of POAG and OHT were 1.31% (95% confidence interval [CI], 1.04-1.62) and 0.47% (95% CI, 0.30-0.70). The rate of progression of baseline OHT to POAG at 6 years was 5.32%. Primary open-angle glaucoma incidence was similar (1.37%) in Chinese and Indians and lower (0.80%) in Malays. Malays had higher incidence (0.79%) of OHT than Indians (0.38%) and Chinese (0.37%). Baseline parameters associated with higher risk of POAG were older age (per decade: odds ratio [OR], 1.90; 95% CI, 1.54-2.35; P < 0.001), higher baseline IOP (per mmHg: OR, 1.20; 95% CI, 1.12-1.29; P < 0.001) and longer axial length (per mm: OR, 1.22; 95% CI, 1.07-1.40, P= 0.004). Six-year incidence of POAG was 1.31% in a multiethnic Asian population. Older age, higher IOP, and longer axial length were associated with higher risk of POAG. These findings can help in future projections and guide public healthcare policy decisions for screening at-risk individuals. The authors have no proprietary or commercial interest in any materials discussed in this article.

The potential for mitochondrial therapeutics in the treatment of primary open-angle glaucoma: a review.

Glaucoma, an age-related neurodegenerative disease, is characterized by the death of retinal ganglion cells (RGCs) and the corresponding loss of visual fields. This disease is the leading cause of irreversible blindness worldwide, making early diagnosis and effective treatment paramount. The pathophysiology of primary open-angle glaucoma (POAG), the most common form of the disease, remains poorly understood. Current available treatments, which target elevated intraocular pressure (IOP), are not effective at slowing disease progression in approximately 30% of patients. There is a great need to identify and study treatment options that target other disease mechanisms and aid in neuroprotection for POAG. Increasingly, the role of mitochondrial injury in the development of POAG has become an emphasized area of research interest. Disruption in the function of mitochondria has been linked to problems with neurodevelopment and systemic diseases. Recent studies have shown an association between RGC death and damage to the cells' mitochondria. In particular, oxidative stress and disrupted oxidative phosphorylation dynamics have been linked to increased susceptibility of RGC mitochondria to secondary mechanical injury. Several mitochondria-targeted treatments for POAG have been suggested, including physical exercise, diet and nutrition, antioxidant supplementation, stem cell therapy, hypoxia exposure, gene therapy, mitochondrial transplantation, and light therapy. Studies have shown that mitochondrial therapeutics may have the potential to slow the progression of POAG by protecting against mitochondrial decline associated with age, genetic susceptibility, and other pathology. Further, these therapeutics may potentially target already present neuronal damage and symptom manifestations. In this review, the authors outline potential mitochondria-targeted treatment strategies and discuss their utility for use in POAG.

Causal factors in primary open angle glaucoma: a phenome-wide Mendelian randomisation study

Primary open angle glaucoma (POAG) is a chronic, adult-onset optic neuropathy associated with characteristic optic disc and/or visual field changes. With a view to identifying modifiable risk factors for this common neurodegenerative condition, we performed a ‘phenome-wide’ univariable Mendelian randomisation (MR) study that involved analysing the relationship between 9661 traits and POAG. Utilised analytical approaches included weighted mode based estimation, the weighted median method, the MR Egger method and the inverse variance weighted (IVW) approach. Eleven traits related to POAG risk were identified including: serum levels of the angiopoietin-1 receptor (OR [odds ratio] = 1.11, IVW p = 2.34E-06) and the cadherin 5 protein (OR = 1.06, IVW p = 1.31E-06); intraocular pressure (OR = 2.46–3.79, IVW p = 8.94E-44–3.00E-27); diabetes (OR = 5.17, beta = 1.64, IVW p = 9.68E-04); and waist circumference (OR = 0.79, IVW p = 1.66E-05). Future research focussing on the effects of adiposity, cadherin 5 and angiopoietin-1 receptor on POAG development and progression is expected to provide key insights that might inform the provision of lifestyle modification advice and/or the development of novel therapies.

Clinical features of the progression of primary open-angle glaucoma in patients with a burdened family history

PURPOSE. To identify clinical and epidemiological features of the course of primary open-angle glaucoma (POAG) in patients with a verified family history of the disease.METHODS. The study protocol included data from 103 people (103 eyes), among them 37 (35.9%) men and 66 (64.1%) women. Group 1 (44 people, 44 eyes) included patients with sporadic glaucoma. Group 2 consisted of patients with a hereditary form of the disease (41 people, 41 eyes). Healthy individuals (18 people, 18 eyes) comprised the control group. Mean age of all patients at the time of final examination was 60.6 (56.0; 66.3) years. In all cases, the diagnosis was established in accordance with the system of differential diagnosis of diseases. Examination was always carried out in person and included routine and specialized study methods (static automated perimetry, optical coherence tomography, examination of the thickness of the cornea in the central optical zone).RESULTS. The mean age of patients with a family history at the time of POAG diagnosis was 59.8 (53.9; 63.1) years, in patients with sporadic glaucoma — 63.85 (58.5; 67.9) years. Therefore, POAG in the group with a family history was diagnosed 4.05 years earlier. No significant differences in the structural and functional characteristics of the visual analyzer were established. A greater number of patients with the sporadic form of the disease undergo glaucoma surgery (47.7% and 34.1%, respectively) in comparable disease duration.CONCLUSION. In people with a family history of glaucoma, preventive screening should be carried out at an earlier age than the average in the population.

Study of the relationship between serum lipid levels and primary open-angle glaucoma.

To determine the association between serum lipid levels and primary open-angle glaucoma (POAG). In this case-control study, 50 patients with POAG documented by clinical tests using standard ophthalmologic equipment and 50 age-matched controls were investigated. Twelve-hour fasting serum lipid profiles, including total cholesterol, serum triglycerides, low-density lipoproteins (LDLs), and high-density lipoproteins (HDLs), were compared between the cases and controls. The mean age of cases and controls was 62.84 ± 9.68 and 60.12 ± 8.65, respectively (P = 0.65). High total cholesterol levels (>200 mg/dl) were found in 23 cases (46%) and 8 controls (16%); high serum triglyceride levels (>150 mg/dl) were found in 24 cases (48%) and 7 controls (14%); high LDL levels (130 mg/dl) were found in 28 cases (56%) and 9 controls (18%); and low HDL levels (<40 mg/dl) were found in 38 cases (76%) and 30 controls (60%). The mean total cholesterol levels were 205.24 ± 36.90 mg/dl in cases and 177.68 ± 22.56 mg/dl in controls (P < 0.001); the mean serum triglyceride levels were 150.42 ± 49.55 mg/dl and 130.84 ± 23.16 mg/dl, respectively (P = 0.013); and the mean LDL levels were 139.50 ± 31.03 mg/dl and 114.96 ± 17.73 mg/dl, respectively (P < 0.001). The mean cholesterol, triglyceride, and LDL levels were significantly higher in cases than in controls (P < 0.05). The present study shows that higher proportion of POAG patients have dyslipidemia compared to age-matched controls. Though these findings need to be replicated by others. This study opens new vistas for further studies, such as lowering dyslipidemia, lowering the intra-ocular pressure and incidence of POAG, and whether the use of statins to reduce dyslipidemia affects the progression of POAG.

Risk factors for structural and functional progression of primary open-angle glaucoma in an African ancestry cohort

Background/aimsTo investigate the rates of structural and functional progression of primary open-angle glaucoma in an African ancestry cohort and identify risk factors for progression.MethodsThis retrospective study included 1424 eyes from...

Системная гипотония и низкое перфузионное давление как факторы прогрессирования первичной открытоугольной глаукомы

Glaucoma progression is still a relevant issue in up-to-date ophthalmology. An important prerequisite for stabilizing glaucoma is the achievement of the target intraocular pressure (IOP). However, many patients with primary open-angle glaucoma (POAG) continue to suffer vision loss despite IOP reduction. Additional factors are also important for glaucoma progression, e.g., blood pressure (BP) and ocular perfusion pressure (OPP). Multiple published data have shown a decrease in blood flow velocity in the retrobulbar vessels, choroid, retina, and optic nerve in patients with glaucoma. A decrease in OPP is a predictor of insufficient intraocular blood supply. Systemic BP has a strong effect on OPP. Intensive treatment for hypertension significantly reduces BP, decreases OPP, and prevents the progression of glaucomatous optic neuropathy. A new paradigm shift that implies a personalized approach to the choice of diagnostic and treatment strategy for glaucoma is emerging. This paper reviews current published data on the effect of systemic hypotension and low OPP on POAG progression. KEYWORDS: glaucoma, intraocular pressure, blood pressure, hypertension, hypotension, perfusion pressure. FOR CITATION: Мyakonkaya O.S., Sarkisyan A.S., Seleznev A.V., Kuroyedov A.V., Brezhnev A.Yu. Systemic hypotension and low perfusion pressure as risk factors for primary open-angle glaucoma progression. Russian Journal of Clinical Ophthalmology. 2023;23(4):202–206 (in Russ.). DOI: 10.32364/2311-7729-2023-23-4-5.

Intraocular pressure changes during Valsalva maneuver

Background: Valsalva maneuver (VM) is the performance of forced expiration against a closed glottis. Activities such as straining during defecation, blowing a balloon, lifting heavy weights, or playing the wind instruments like saxophone entail the performance of the VM. Even though many parameters such as blood pressure and pulse rate are changed to certain extent during VM. Aims and Objectives: This study aims to know whether any intraocular pressure (IOP) changes take place by performing VM. IOP is the fluid pressure of the eye. Increased IOP leads to ischemia of retinal nerve fiber. Decreased IOP can lead to impairment of the ocular functions. Elevation of IOP is the major risk factor to develop glaucoma primary open-angle glaucoma (POAG). Materials and Methods: 52 intern students (28 males and 24 females) among 20 myopics and 32 emmetropes are selected for this study from GITAM Institute of Medical Sciences and Research. Complete systemic and ocular examination is conducted. IOP is recorded with the correction of central corneal thickness. All of them are trained for “Valsalva Maneuver” for 10 days during their stay in unit posting. VM is practiced for 2 min. The IOPs recorded before and after the VM procedure. Results: There is a rise in the IOP after VM in all the 52 internee students. The average raise in the IOP after VM for 2 min is about 2.81 mmHg. IOP raised more in females than males. There is an increase of IOP in emmetropes than myopes. Conclusion: VM raises the IOP in all the individuals. The POAG individuals should be cautioned during the weight lifting, conditions which may lead to increase the intra-abdominal pressure. These conditions cause the natural VM. All these maneuvers can cause fluctuations in the IOP, which are dangerous and may lead to the progression of POAG. VM can be used as screening procedure for glaucoma.

Prediction of the rate of progression of primary open-angle glaucoma depending on gender and polymorphism of the endothelial NO-synthase (NOS3) gene

Relevance – it is promising to develop a system for the diagnosis and prevention of primary open-angle glaucoma (POAG), which would be based on the determination of constitutive propensity factors and would be able to predict the onset and progression of the disease. The aim of the study was to develop a model for predicting the rate of progression of primary open-angle glaucoma depending on gender and endothelial NO-synthase (NOS3) gene polymorphism. There were genotyped 153 patients with POAG aged 36-84 years. Genotypes rs1799983 and rs207074 were determined in the blood of patients by real-time polymerase chain reaction (amplifier Gene Amp® PCR System 7500; USA) using the TaqMan Mutation Detection Assays Life-Technology test system (USA). For mathematical processing of the obtained results, the Statistica 10 program (StatSoft, Inc., USA) was used. The rate of progression of POAG was higher in the presence of risk alleles in the haplotype of the NOS3 gene polymorphisms: T rs1799983 and C rs2070744 (haplotypes TT-CC, GT-CC and GT-CT), which, when distributed by gender, was more pronounced in women than in men of each of the possible haplotypes. The maximum difference was noted for carriers of the TT-SS haplotype, in whom the rate of progression of POAG in women exceeded that in men by 1.4 times (p&lt;0.001). A regression model was built with satisfactory prediction indicators (multiple correlation coefficient R=0.963; coefficient of determination R2=0.928; p&lt;0.001). The probable “hereditary” age of patients in which one or another stage of POAG should be expected is calculated. Gender and haplotypes rs1799983 and rs2070744 of the NOS3 gene were shown to be associated with the onset and rate of progression of POAG, which was implemented in the prognostic model of the disease. Separately for men and women, carriers of different haplotypes, the rate of progression and the possible age of POAG development by stages were calculated.

Factors in the development of refractory primary open-angle glaucoma (part 1)

Primary open-angle glaucoma (POAG) is one of the most significant medico-social problems in the modern society. The development of its refractoriness aggravates the pathological process and inevitably leads to blindness. Despite the fact that this form accounts for up to 80% of all glaucoma cases, the problem of POAG refractoriness has not been considered in sufficient detail in either Russian or foreign sources. The article presents an overview of the main ophthalmic factors that contribute to changes in various structures of the eyeball and accelerate the formation of refractory forms of POAG. One of the reasons for that is a genetic predisposition to the development of POAG. It is worth noting that in 60% of patients with a family history of glaucoma, the risk of developing POAG increases by 10 times (among the first-degree relatives).Additional factors in the development of the refractory form of POAG are the reactive syndrome and during laser surgery. It is important to emphasize that the risk of development and progression of POAG in patients with a hereditary predisposition is much higher, while indicating a number of therapeutic measures may lead to drug resistance. Genotyping is a promising scientific and practical direction of research, allowing prediction of the pharmacological response to a particular drug and individual selection of the appropriate therapy according to the patient's genotype. This approach could help prevent a number of complications and improve the accuracy of disease prognosis.