Glaucomatous Optic Neuropathy Research Articles

Deep learning architectures and transfer learning for detecting glaucomatous optic neuropathy: A review

Relevance: Glaucoma is a group of diseases characterized by progressive, bilateral yet asymmetric optic neuropathy, which results in permanent vision loss when is not treated promptly; It is asymptomatic in the early stages; thus, unfortunately, the diagnosis is discovered when the compromise is already severe, and the condition is advanced. Because of this, it is crucial to conduct early screening using technologies that are accessible to the population. Artificial intelligence (AI), particularly deep learning (DL), plays an essential role in this issue. DL may be an efficient approach for glaucoma screenings with the proper training. Objective: Describe the development of AI and DL over time and their use and significance in glaucoma screening. Methods: A literature search was conducted in PUBMED/MEDLINE, EMBASE, and manuscript references in English and Spanish between January 2014 to July 2022 on the role and evolution of AI and DL over the years and the usefulness of deep learning for glaucoma diagnosis. Of the 1914 abstracts reviewed, 105 articles were selected that contained information on the history of AI in medicine and the applicability of this tool for the early diagnosis of glaucoma. Findings and conclusions: We can demonstrate that deep learning can outperform glaucoma specialists in diagnosing the condition through fundus imaging data; DL is an exciting tool in the screening and early diagnosis of glaucoma.

Влияние нарушения венозного оттока в синусах головного мозга на прогрессирование глаукомного процесса

Purpose. To evaluate the effect of impaired venous return in the brain sinuses on the progression of glaucoma. Material and methods. We examined 15 people (6 men and 9 women aged 55–85 years) with primary open-angle glaucoma (POAG) of stages I–III and normalized intraocular pressure (IOP) but with the progression of glaucoma optic neuropathy (GON). In addition to the generally accepted ophthalmological methods of examination, optical coherence tomography (OCT) and magnetic resonance imaging (MRI) of the brain with sinusovenography and neurologist consultation were used. Results. The patients had a magnetic resonance pattern of asymmetry of blood flow along the sinuses of the dura mater with a decreased blood flow along the left or right transverse, sigmoid sinuses (signs of sinus hypoplasia), as well as along the left or right internal jugular vein. Magnetic resonance signs of moderate external communicating hydrocephalus were noted in 1 patient. Another patient had magnetic resonance signs of moderate cerebrospinal hypertension in the ventricles and suprasellar cistern. It should be noted that the side of the impaired venous return in the brain sinuses corresponded to the eyes with the progression of GON. The patients underwent complex treatment, including a long course of venotonics to improve venous return, taking into account the recommendations of a neurologist. Conclusion. Impaired venous return in the brain sinuses certainly has a significant negative effect on the progression of GON in patients with POAG and normalized ophthalmotonus. In this regard with the progression of glaucoma, patients with normalized ophthalmotonus are recommended to have an MRI of the brain with sinusovenography. If there is a violation of venous return through the sinuses of the dura mater, which corresponds to the eyes with the progression of GON, a neurologist’s consultation and complex therapy, including a long course of venotonics are indicated. Keywords: primary open-angle glaucoma, normalized intraocular pressure, progression of glaucoma optic neuropathy, impaired venous return in the brain sinuses, complex treatment, venotonics

Ocular and Systemic Factors Associated with Glaucoma.

Dada T, Verma S, Gagrani M, et al. Ocular and Systemic Factors associated with Glaucoma. J Curr Glaucoma Pract 2022;16(3):179-191.

Сравнительный анализ гемодинамических и электрофизиологических показателей на фоне комплексного лечения глаукомной оптической нейропатии эндоназальным электрофорезом в сочетании с электростимуляцией

Цель. Сравнительная оценка комплексного лечения глаукомной оптической нейропатии с введением препарата танакан с помощью эндоназального электрофореза в сочетании с электростимуляцией по данным ЗВП и ультразвукового доплеровского картирования. Материалы и методы. Исследование проводилось в Самаркандской областной глазной больнице и клинике Самаркандского государственного медицинского университета. Под наблюдением находились 80 пациентов (116 глаз) с глаукомной оптической нейропатией (ГОН) в возрасте от 40 до 78 лет, из них 44 (55%) женщины и 36 (45%) мужчин, с установленным диагнозом первичной открытоугольной и закрытоугольной глаукомы II или III стадии в условиях компенсации внутриглазного давления (21,3±3,2). Все пациенты были разделены на три гомогенные группы. В третьей группе помимо нейропротекторного лечения и эндоназального электрофореза использовалась чрескожная электростимуляция зрительного нерва с помощью аппарата ЭСОМ. Результаты. Отмечалось улучшение остроты зрения в 1,32 раза у пациентов со II стадией и в 1,4 раза – у лиц с III стадией болезни во 2-й основной группе уже через месяц после проведенной терапии по сравнению с группой контроля. Суммарные границы периферического поля зрения также были достоверно расширены во 2-й основной группе. Также следует отметить улучшение гемодинамических показателей сосудов зрительного нерва в этой группе со сравнительно сниженным индексом резистентности в большей степени, изменение которого составило от 0,66 до 0,57 к 6-му месяцу наблюдения. Кроме того, увеличение амплитуды зрительных вызванных потенциалов подтверждает достоверный положительный эффект чрескожной электростимуляции (p≤0,05) во 2-й основной группе. Заключение. Использование эндоназального электрофореза с препаратом танакан в сочетании с чрескожной электростимуляцией в комплексном лечении ГОН снижает риск развития атрофии зрительного нерва и наряду с улучшением зрительных функций удлиняет положительный эффект основного лечения. Предложенный в работе метод комплексного лечения позволит повысить эффективность терапии пациентов с компенсированной первичной глаукомой, улучшит прогноз по зрению и качество реабилитационных мероприятий. Purpose. To assess comparative effectiveness of complex treatment of glaucomatous optic neuropathy with drug tanakan using endonasal electrophoresis in combination with electrostimulation based on VEP and ultrasound doppler mapping. Materials and methods. The study was carried out in Samarkand regional eye hospital and Samarkand state medical university. Under observation were 80 (116 eyes) patients with glaucomatous optic neuropathy aged 40 to 78, from them 44 (55%) – female, 36 (45%) – male with fixed diagnosis primary open angel and angle closure glaucoma of the II or III stages in compensated intraocular pressure (21.3±3.2). All patients were divided into three groups. In the third group patients beside neuroprotective treatment and endonasal electrophoresis took transcutaneous electrostimulation of the optic nerve with ESOM apparatus. Results. An improvement of the visual acuity in 1.32 times in the II stage and 1.4 times in the III stage in the II main group was noted compare to control one. Total boundaries of the peripheral visual field also were reliably enlarged in the II main group. It should be noted that hemodynamic index of vessels of the optic nerve with comparatively low index of the resistance were higher also in the given group and made up from 0.66 to 0.57 in the 6-months of observation. On top of that, enlargement of the visual evoke potential amplitude supported reliable positive effect of the transcutaneous electrostimulation (p≤0.05) in the II main group. Conclusion. The usage of endonasal electrophoresis with tanakan following with percutaneous electrostimulation in complex treatment of glaucomatous optic neuropathy protect from the development of the atrophy of optic nerve and along with improvements of visual functions prolong positive effect of the main treatment. Proposed complex treatment enables to increase effectiveness of treatment patents with compensate primary glaucoma, improves visual prognosis and quality of the rehabilitation measurements.

Automated macular segmentation can distinguish glaucomatous from compressive optic neuropathy

PurposeTo compare macular damage in glaucomatous optic neuropathy (GON) and compressive optic neuropathy (CON) and assess its diagnostic accuracy in distinguishing between diseases.MethodsObservational, cross-sectional, single-center study. Patients with GON, CON, and healthy controls were included according to the eligibility criteria. An automated spectral-domain optical coherence tomography (SD-OCT) algorithm was used to segment the circumpapilary retinal nerve fiber layer (cpRNFL) and macula. The layer thickness was measured in each sector according to the Early Treatment Diabetic Retinopathy Study and the 6-sector Garway-Heath-based grids. Data was compared across all study groups, and the significance level was set at 0.05.ResultsSeventy-five eyes of 75 participants, 25 with GON, 25 with CON, and 25 healthy controls (CG), were included. Macular thickness was diminished in the ganglion cell complex of GON and CON patients compared to CG (p<0.05). The best Garway-Heath-based grid parameters for distinguishing GON and CON were the nasal-inferior (NI) and nasal-superior sectors and the NI/temporal inferior (TI) damage ratios in the macular ganglion cell (mGCL) and inner plexiform (IPL) layers. Moreover, the combination of the NI sector and NI/TI damage ratios in both layers had higher discriminative power (AUC 0.909; 95% CI 0.830–0.988; p<0.001) than combining parameters in each layer separately.ConclusionOur findings suggest that the evaluation of macular segmented layers damage by SD-OCT may be a helpful add-on tool in the differential diagnosis between GON and CON.

Iridotomy to slow progression of visual field loss in angle-closure glaucoma.

Primary angle-closure glaucoma is a type of glaucoma associated with a physically obstructed anterior chamber angle. For example, contact between the iris and lens at the pupillary margin creates a pupillary block that increases resistance to aqueous outflow. Obstruction of the anterior chamber angle blocks drainage of fluids (aqueous humor) within the eye and may raise intraocular pressure (IOP). Elevated IOP is associated with glaucomatous optic nerve damage and visual field loss. Laser peripheral iridotomy ('iridotomy') is a procedure to eliminate pupillary block by allowing aqueous humor to pass directly from the posterior to anterior chamber, which is achieved by creating a hole in the iris using laser. Iridotomy is used to treat patients with primary angle-closure glaucoma, patients with primary angle-closure (narrow angles and no signs of glaucomatous optic neuropathy), and patients who are primary angle-closure suspects (patients with reversible obstruction). However, the effectiveness of iridotomy on slowing progression of visual field loss is uncertain. To assess the effects of iridotomy compared with no iridotomy for primary angle-closure glaucoma, primary angle-closure, and primary angle-closure suspect. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2021, Issue 10), which contains the Cochrane Eyes and Vision Trials Register; MEDLINE Ovid; Embase Ovid; PubMed; LILACS; ClinicalTrials.gov; and the WHO ICTRP. The date of the most recent search was 10 October 2021. Randomized or quasi-randomized controlled trials that compared iridotomy with no iridotomy in primary angle-closure suspects, people with primary angle-closure, or people with primary angle-closure glaucoma in one or both eyes were eligible. We used standard Cochrane methodology and assessed the certainty of the body of evidence for prespecified outcomes using the GRADE approach. We identified four studies (3086 eyes of 1543 participants) that compared iridotomy with no iridotomy in participants (range of mean age 59.6 to 62.9 years) who were primary angle-closure suspects from China, Singapore, or the UK. Study investigators randomized one eye of each participant to iridotomy and the other to no iridotomy. Two studies provided long-term (five or more years) results. We judged the certainty of the evidence as moderate to low across the prespecified outcomes, downgrading for high risk of bias (e.g. performance and detection biases) and imprecision of results. Meta-analyses of data from two studies suggest that iridotomy probably results in little to no difference in IOP compared with no iridotomy at one year (mean difference (MD) 0.04 mm Hg, 95% confidence interval (CI) -0.17 to 0.24; I2 = 65%; 2598 eyes of 1299 participants; moderate certainty evidence) and five years (MD 0.12 mm Hg, 95% CI -0.11 to 0.35; I2 = 0%; 2016 eyes of 1008 participants), and in best-corrected visual acuity measured as logMAR at one year (MD 0.00, 95% CI -0.01 to 0.01; I2 = 69%; 2596 eyes of 1298 participants; moderate certainty evidence) and five years (MD 0.01, 95% CI -0.01 to 0.03; I2 = 0%; 2002 eyes of 1001 participants). In terms of gonioscopic findings, eyes treated with iridotomy likely had wider angles in Shaffer grading scale (MD 4.93 units, 95% CI 4.73 to 5.12; I2 = 59%; 2598 eyes of 1299 participants at one year; MD 5.07, 95% CI 4.78 to 5.36; I2 = 97%; 2016 eyes of 1008 participants at five years; moderate certainty evidence) and experienced fewer peripheral anterior synechiae (PAS) than eyes that received no iridotomy at five years (risk ratio (RR) 0.41, 95% CI 0.24 to 0.67; I2 = 28%; 2 studies, 2738 eyes of 1369 participants), but the evidence was less conclusive at one year (RR 0.62, 95% CI 0.25 to 1.54; I2 = 57%; 3 studies, 2896 eyes of 1448 participants; low certainty evidence). No studies reported data on the proportion of participants with progressive visual field loss during follow-up (the primary outcome of this review), mean number of medications to control IOP, or quality of life outcomes. Low certainty evidence suggests that iridotomy may result in little to no difference in the incidence of acute angle-closure (RR 0.29, 95% CI 0.07 to 1.20; I2 = 0%; 3 studies, 3006 eyes of 1503 participants). Other ocular adverse events (e.g. eye pain, dry eye, redness of eyes, and ocular discomfort), although rare, were more common in eyes treated with iridotomy than in eyes in the control group. AUTHORS' CONCLUSIONS: We did not find sufficient evidence to draw any meaningful conclusions on the use of iridotomy for the purpose of slowing progression of visual field loss. No study reported on progressive visual field loss, the primary outcome of this review. Although there is moderate certainty evidence that iridotomy results in improved gonioscopic findings, in is unclear if these findings translate to clinically meaningful benefits.

Multifunctional Protein Alpha2-Macroglobulin in Tear Fluid and Blood Serum of Patients with Glaucoma

Alpha2-macroglobulin (α2-MG) is a multifunctional glycoprotein. Due to the variety of its functions there can be several ways of its involvement in the pathogenesis of the glaucomatous optic neuropathy, including neuroinflammation, amyloid deposition, neurotoxicity. It is known that α2-MG level in aqueous humor is increased in glaucoma but there is scant information about its concentration in blood and tear fluid.Purpose. To determine the α2-MG activity in tear fluid and blood serum of glaucoma patients to broaden of understanding of its role in the pathogenesis of glaucoma and to estimate its informativity for the characterization of the disease clinical course.Methods. Tear fluid was collected from 21 patients with primary open-angle glaucoma and 17 healthy adults. Activity of α2-MG was measured enzymatically with BAPNA as a substrate.Results. Activity of α2-MG in tears was 20 times lower than in blood serum. In healthy controls it was 4.66 ± 0.27 nmol / min×ml in tears and 92.35 ± 5.44 nmol / min×ml in blood. Totally in glaucoma patients it was 54 % higher than in controls in tears (р &lt; 0.008), and 35 % higher in blood (р &lt; 0.05). Particularly patients without pseudoexfoliative syndrome showed a significant α2-MG activity increase in tears (2 times) while in serum it was 67 % higher than in controls. In patients with pseudoexfoliative glaucoma α2-MG activity was not increased in tears nor in blood.Conclusion. Primary open-angle glaucoma without pseudoexfoliative syndrome cause the increase of α2-MG activity in tears and in blood in contrast with pseudoexfoliative glaucoma. This fact indicates that pathogenetic ways of these types of glaucoma are different. The increased α2-MG activity may be the risk factor for the development of glaucoma without pseudoexfoliative syndrome.

Анализ частоты сопутствующей офтальмопатологии у лиц с катарактой (результаты популяционного исследования)

Aim: to assess the prevalence and characteristics of various types of cataracts and to analyze most common eye comorbidities from the population study "Ural Eye and Medical Study" (UEMS). Patients and Methods: this population study included 5899 individuals (3400 living in the rural area and 2499 living in the city). Eye examinations included uncorrected and best-corrected visual acuity measurements, autorefractometry, slit lamp examination, A-scan ultrasound biometry, non-contact tonometry, fundoscopic examination, corneal topography, fundus photography, static perimetry, and optical coherence tomography. Results: cataracts were diagnosed in 2616 patients (44.3%). These patients were more commonly rural residents and women. Nuclear cataracts (n=1575, 60.2%) were detected 1.5 times more often than cortical cataracts (n=1041, 39.8%). Eye comorbidities were diagnosed in 975 patients (37.3%). The most common eye comorbidities were retinal diseases. Among them, age-related macular degeneration (AMD) ranked first (13.46%). Glaucomatous optic neuropathy (GON)/glaucoma) and myopic macular degeneration/myopia were also common (6.77% and 4.93%, respectively). Diabetic retinopathy (DR) was reported less common (2.26%). The rate of eye comorbidities in patients was 43.6% in cortical cataracts and 33.1% in nuclear cataracts. As to individual conditions, the greatest difference was reported for AMD rate (19.12%) and macular hole/MH (1.8%), which were diagnosed twice more often in cortical cataracts (p&lt;0.05) than in nuclear cataracts (9.71% and 0.8%, respectively). Conclusion: the structure of eye comorbidities in patients with nuclear and cortical cataracts was almost similar to that in patients with cataracts overall. However, the rate of eye comorbidities in patients with cortical cataracts was significantly higher than in patients with nuclear cataracts. This particularly applies to AMD and MH. In general, the rate of AMD, GON, DR, and MH in patients with complicated cataracts increases with age. These diseases were most often diagnosed in women and urban residents, except for AMD (more patients with AMD live in rural areas). KEYWORDS: cataract, nuclear, cortical, eye comorbidities, population study. FOR CITATION: Bikbov M.M., Orenburkina O.I., Gilmanshin T.R., Babushkin A.E. The rate of eye comorbidities in patients with cataracts (results of a population study). Russian Journal of Clinical Ophthalmology. 2023;23(3):146–151 (in Russ.). DOI: 10.32364/2311-7729-2023-23-3-6

Application of IPSC and Müller glia derivatives in retinal degenerative diseases.

Retinal degenerative diseases cause blindness characterized by a progressive decline in the number and function of retinal pigment epithelium (RPE), photoreceptor cells, and ganglion cells. Such diseases include retinitis pigmentosa (RP), glaucomatous optic neuropathy, age-related macular degeneration and diabetic optic neuropathy. Recent studies have demonstrated that Müller glial cells (MGCs), an endogenous alternative source of retinal neurons, are important glial cells involved in retinal development, damage, and regeneration, making it an excellent target for retinal nerve regeneration. Although hardly differentiate into neuron cells, transplanted MGCs have been shown to induce partial recovery of visual function in experimental retinal degenerative models. This improvement is possibly attributed to the release of neuroprotective factors that derived from the MGCs. With the development of the therapeutic usage of pluripotent stem cell, application of induced pluripotent stem cells (iPSCs) or embryonic stem cells (ESCs) originated derivation of MGCs have been widely used in retinal degenerative disease model such as glaucoma and retinitis pigmentosa model. This chapter summarized the relevant research and mechanisms and provided a broader application and research prospects for effective treatments in retinal degenerative diseases.

Therapeutic possibilities of stimulating reparative neurogenesis in patients with glaucoma who have recovered from a coronavirus infection

This study aimed to conduct a comprehensive diagnosis of the severity of oxidative stress, identify changes in the neuroplasticity and reparative ability of the retina in patients with primary open-angle glaucoma (POAG) who have recovered after a coronavirus infection, and are undergoing therapy with the complex drug Cytoflavin. The study included 40 patients (mean age 57.2±3.6 years) with advanced POAG compensated by hypotensive agents; all of them recovered from moderate Covid-19 30 to 90 days prior to inclusion in the study. Twenty patients of the main group received therapy with the complex drug Cytoflavin, 20 other patients comprised the control group. In the comparison groups, the concentration of BDNF and CNTF in blood serum (SC) was determined by enzyme-linked immunosorbent assay (ELISA). Overall assessment of oxidative stress was done by high performance liquid chromatography. Studies of the functional activity of the retina were performed using the Tomey EP 1000 electroretinograph according to the standard method. Retinal photosensitivity significantly improved in patients of the main group taking the complex drug Cytoflavin (mD mean after treatment increased from -7.34±0.62 dB to -4.52±0.12 dB (p>0.001), PSD mean decreased from 6.23±0.21dB to 4.27±0.13 dB (p>0.001)); the neural activity of the retina improved according to PERG (the amplitudes of the P50 and N95 components increased from 0.92±0.04 µv to 1.65±0.01 µv and from 1.83±0.06 µv to 2.68±0.01 µv, respectively (p>0.001), the latency of the P50 and N95 components decreased from 53.40±2.51 ms to 49.37±2.22 ms and from 112.40±5.23 ms to 107.4±8.11ms, respectively (p>0.001); the concentration of BDNF increased (from 18.65±5.32 ng/ml to 20.23±4.05 ng/ml (p>0.001)) and the concentration of CNTF in the blood serum decreased (from 3.99±0.37 pg/ml to 1.85±0.02pg/ml (p>0.001)), the severity of oxidative stress decreased (the indicator of oxidative stress decreased by 1.4 times after treatment p>0.001) and the content of antioxidant protection indicators increased: the indicator of antioxidant protection of blood serum increased by 1.4 times, the concentration of superoxide dismutase - by 1.9 times (p>0.001), glutathione peroxidase - by 1.4 times (p>0.001), coenzyme Q10 - by 4.5 times (p>0.001). The obtained data can be used to determine the risk of progression of glaucomatous optic neuropathy in patients with glaucoma who have had a coronavirus infection.

The Patterns of Visual Field Defects in Primary Angle-Closure Glaucoma Compared to High-Tension Glaucoma and Normal-Tension Glaucoma

Introduction: The aim of this study was to compare the patterns of visual field (VF) defects in primary angle-closure glaucoma (PACG) to control groups of eyes with high-tension glaucoma (HTG) and normal-tension glaucoma (NTG). Methods: Forty-eight eyes with PACG were enrolled, and control eyes with HTG and NTG matched for age, sex, and mean deviation of VF defect were selected. VF tests were performed using the 24-2 program of the Humphrey field analyzer. VF defects were classified into six patterns with the Ocular Hypertension Treatment Study classification system and were categorized into three stages (early, moderate, and advanced). Each hemifield was divided into five regions according to the Glaucoma Hemifield Test (GHT). The mean total deviation (TD) of each GHT region was calculated. Results: Compared with HTG and NTG groups, the partial arcuate VF defects were more common in the PACG group. In the PACG group, the nasal GHT region in the inferior hemifield had the worst mean TD (−8.48 ± 8.62 dB), followed by the arcuate 1 (−7.81 ± 7.91 dB), arcuate 2 (−7.46 ± 7.43 dB), paracentral (−7.19 ± 7.98 dB), and central (−5.14 ± 6.24 dB) regions; the mean TD of the central region was significantly better than those for all other regions (all p < 0.05). A similar trend was observed in the superior hemifield in the PACG group but not the VF hemifields of the HTG and NTG groups. Conclusion: Patterns of VF defect in PACG patients differ from those with HTG and NTG. This discrepancy might be due to the differences in the pathogenic mechanisms of glaucomatous optic neuropathy.

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.

The value of lamina cribrosa in the diagnosis and treatment of glaucoma. Remodeling of lamina cribrosa collagen and approaches to its therapeutic treatment

Among the first structures suffering damage with an increase in intraocular pressure (IOP) and in early stage of glaucoma are the lamina cribrosa (LC) and peripapillary sclera (ppScl). Changes in these structures occur at the molecular and cellular level. Extracellular matrix (ECM) is the basis of connective tissue, provides mechanical support for the cells, facilitates intercellular interactions and transport of chemicals, including in LC and ppScl. Mechanical stress causes remodeling and disorganization of the ECM, which leads to changes in the structure of the tissue itself, an increase in its rigidity and a decrease in elasticity. Taking into account the molecular and cellular mechanisms of damage to LC and ppScl, various researchers have developed strategies and tactics for therapeutic intervention on these structures, contributing to a decrease in ECM secretion and, as a consequence, suspension of their remodeling. These approaches may in the future form the basis for the treatment of glaucomatous optic neuropathy.

Клинико-морфологическая характеристика глаукомной оптической нейропатии при различных стадиях вторичной глаукомы у собак

This paper presents a correlation between the clinical and histomorphological picture, as well as electrophysiological data characteristic of different stages of glaucoma optic neuropathy in dogs. Glaucoma is a common disease among small pets, in particular dogs, leading to impaired visual functions and blindness, which significantly reduces the quality of life of the animal. Blindness develops due to increased intraocular pressure, which leads to damage to various layers of the retina, the optic nerve disc and microcirculation disorders. Therefore, the main task in the treatment of dogs with glaucoma is the preservation of visual functions. In this work, a study was conducted to assess the clinical picture in 60 dogs with various stages of glaucoma, as well as in 18 dogs, a histomorphological study was also conducted with various stages of the glaucoma process. As a result of the conducted studies, clinical manifestations of fundus changes in the glaucomatous process in dogs have been identified and substantiated. It is shown that the clinical manifestation of glaucomatous lesion is polymorphic and depends on the severity of the course and duration of the disease. The established correlation between the data of ophthalmoscopy, fundoscopy, electroretinography and histomorphology allows classifying the disease into three stages: initial (from 1 to 5–7 days), advanced (from 7 to 30–45 days) and terminal (more than 30–45 days). Objective diagnostic symptoms of glaucomatous lesions of the posterior segment of the eyeball are: paleness of the ZEN and expansion of the excavation of the ZEN, a decrease in the neuroretinal girdle, thinning of retinal vessels, hyperreflexia of the tapetal zone.

The place of endoscopic laser cyclodestruction in the system of microinvasive glaucoma surgery

Glaucoma is one of the leading causes of irreversible blindness in the world. Reducing intraocular pressure is the only way to slow down the progression of glaucomatous optic neuropathy. Minimally invasive glaucoma surgery aims to provide a safer way of reduction of intraocular pressure than traditional methods, and at the same time it is capable to reduce dependence on antihypertensive therapy. Cyclodestructive high-precision method of reducing the production of aquоeus humor occupies a confident position among modern minimally invasive glaucoma surgery methods. The data obtained as a result of studying the literature confirm our idea on the endoscopic laser cyclodestruction method as a minimally invasive, safe, reliable antiglaucomatous component of the combined surgical treatment of cataract and glaucoma.

Advances in artificial intelligence applications for ocular surface diseases diagnosis.

In recent years, with the rapid development of computer technology, continual optimization of various learning algorithms and architectures, and establishment of numerous large databases, artificial intelligence (AI) has been unprecedentedly developed and applied in the field of ophthalmology. In the past, ophthalmological AI research mainly focused on posterior segment diseases, such as diabetic retinopathy, retinopathy of prematurity, age-related macular degeneration, retinal vein occlusion, and glaucoma optic neuropathy. Meanwhile, an increasing number of studies have employed AI to diagnose ocular surface diseases. In this review, we summarize the research progress of AI in the diagnosis of several ocular surface diseases, namely keratitis, keratoconus, dry eye, and pterygium. We discuss the limitations and challenges of AI in the diagnosis of ocular surface diseases, as well as prospects for the future.

Clinical presentation of acute primary angle closure during the COVID-19 epidemic lockdown.

This study aimed to investigate the clinical presentation of acute primary angle closure (APAC) during the COVID-19 epidemic lockdown in Wuhan. Consecutive patients seeking APAC treatment at the Wuhan Aier Eye Hospital during the 76 days (January 23-April 8, 2020) when the lockdown policy was implemented due to the COVID-19 pandemic were compared to those during the same period the following year (January 23-April 8, 2021), when the lockdown policy was not implemented. The cohorts were compared to assess demographic variables and clinical presentations. A total of 54 patients (64 eyes) were included in the 2020, compared with 46 patients (51 eyes) in the 2021. Demographic factors were similar between the groups. Significantly more patients developed blindness in the 2020 cohort (21.87%) than in the 2021 cohort (7.84%). Patients in the 2020 showed a longer time from symptom to treatment (241.84 ± 211.95 h in 2020 vs. 121.53 ± 96.12 h in 2021; P = 0.001), higher intraocular pressure at presentation (52.63 ± 12.45 mmHg in 2020 vs. 45.16 ± 9.79 mmHg in 2021; P = 0.001), larger pupil diameter (5.47 ± 1.62 mm in 2020 vs. 4.33 ± 1.27 mm in 2021; P = 0.001), and more glaucomatous optic neuropathy diagnoses [20/64 eyes (31.25%) in 2020 vs. 7/51 eyes (13.73%) in 2021; P = 0.03]. The time between the onset of APAC symptoms and its treatment during the COVID-19 epidemic lockdown was significantly prolonged, which increased the blindness rate of APAC patients.

Efficacy and safety of ab interno trabeculectomy revision with 5-fluorouracil in advanced glaucoma due to subconjunctival fibrosis

ObjectifDécrire les résultats obtenus chez les patients qui ont subi une révision de trabéculectomie ab interno dans un seul œil, accompagnée de 5-fluorouracil. NatureÉtude de cohorte rétrospective. ParticipantsEnsemble des patients qui avaient subi une révision de trabéculectomie ab interno dans un seul établissement de soins tertiaires pendant les 5 années de l’étude. Tous les patients inclus présentaient une neuropathie optique glaucomateuse avancée, sans égard à l’âge et au sous-type de glaucome. MéthodesAu nombre des paramètres d’évaluation, mentionnons la réussite de l'intervention chirurgicale, le nombre de collyres visant à abaisser la pression intraoculaire (PIO), la meilleure acuité visuelle corrigée, la déviation moyenne du champ visuel ainsi que les complications postopératoires. La réussite à 12 mois reposait sur 2 critères : critère A (PIO < 15 mm Hg et baisse de > 20 % de la PIO) et critère B (PIO < 12 mm Hg et baisse de > 20 % de la PIO). Pour chacun des critères de réussite, on a réparti les patients en 2 groupes selon que la baisse de la PIO a été obtenue sans collyre (réussite complète) ou avec l'ajout de collyres (réussite partielle). RésultatsLa présente étude regroupe 46 yeux de 46 patients. De ce nombre, 34 patients ont été suivis pendant au moins 12 mois après l'intervention aux fins d’évaluation de la réussite. Parmi ces 34 patients, le taux de réussite selon le critère A a été de 68 % (réussite complète : 53 %; réussite partielle : 15 %) et le taux de réussite selon le critère B, de 47 % (réussite complète : 38 %; réussite partielle : 9 %). Une hypotonie précoce a été observée dans 68 % des yeux, sans qu'elle soit associée à des résultats négatifs au chapitre de l'acuité visuelle ou des champs visuels. ConclusionsDans l'ensemble, 47 % des patients présentaient une PIO < 12 mm Hg et une baisse de > 20 % de la PIO (avec ou sans recours aux collyres) lors du suivi à 12 mois. On peut s'attendre à l'apparition d'une hypotonie précoce postopératoire transitoire après une révision de trabéculectomie ab interno.

Contribution of intraocular pressure‐dependent and pressure‐independent glaucoma models to neuroprotection

AbstractGlaucoma is considered a heterogeneous group of degenerative optic neuropathies characterized mainly by an ongoing loss of retinal ganglion cells (RGCs) which causes progressive deterioration of the visual field and irreversible blindness. The aetiology and pathophysiology of glaucoma are not known in detail and are a matter of debate. Although the most significant risk factor in the development and progression of glaucoma correlates with elevated intraocular pressure (IOP), at present the only treatment available to prevent or delay its development is to reduce IOP by medication or surgery to slow its detrimental effects. But reducing IOP alone does not stop the progression of the disease. Therefore, IOP may not be the only motive for glaucomatous retinopathy and optic neuropathy, and there could be other hidden mechanisms contributing to the loss of RGCs.A suitable animal model of neurodegenerative disease, such as glaucoma, should be easy to induce and reproduce, feasible and predictable, and allow detection and quantification at the biochemical, morphological and functional levels of the induced pathological changes. However, no model emulates all aspects of a pathology such as glaucoma, which is likely to have more than one aetiology and manifest itself through different pathological mechanisms. Hence, the interest and need to establish and use different experimental models in rodents to improve our understanding of the pathophysiology of glaucoma and to investigate possible neuroprotective agents. In general, experimental models of glaucoma established in rodents involve a transient or chronic increase in IOP above normal values, which allows us to study the pathological changes associated with ocular hypertension. However, elevated IOP may not be the only cause of glaucomatous retinopathy and optic neuropathy, hence the need for models that do not involve an increase in intraocular pressure to deal with specific issues of the evolution of this pathology, such as optic nerve injury, retinal ischaemia/reperfusion, intravitreal injection of excitatory amino acids or endothelin‐induced optic neuropathy.Results obtained in different experimental models of glaucoma mimicking ocular hypertension or optic nerve damage have confirmed the existence of morphofunctional differences in the time course of RGC loss, both between different types of RGCs and between different lesions. As well as the effects on other retinal cell populations. In this regard, in the outer retina, there is a significant contrast between damage caused by ocular hypertension and optic nerve injury. Both axotomy and ocular hypertension induce a selective loss of RGCs, but ocular hypertension also promotes a loss of photoreceptors.Thanks to the different glaucoma models studied, the findings obtained have contributed to improving our knowledge of glaucomatous pathology and to the development of future neuroprotective therapies.

Retinal glial activation in the contralateral eyes in a mouse model of unilateral laser‐induced glaucoma

AbstractGlaucoma is a neurodegenerative chronic pathology, characterized by the loss of retinal ganglion cells (RGC), which leads to an irreversible vision field loss. The glaucomatous optic neuropathy is usually a bilateral disease, though asymmetric in time: this means that the damage initially present in one of the eyes, eventually also appears with a time delay in the contralateral eye. Notably, recent experimental models of unilateral ocular hypertension (OHT) have shown that the fellow normotensive contralateral eyes to hypertensive eyes exhibit changes in glial cells with little or no damage to RGCs.It has been reported that although increased intraocular pressure (IOP) may be the main trigger for this pathology, other pathogenic mechanisms such as neuroinflammation are involved in the RGCs death. Microglial cells constitute the population of immune resident cells, and they play an important role in the physiology and survival of RGC.One of the most widely used experimental models of glaucoma is the unilateral laser‐induced OHT model. In these animals, OHT induces an alteration of retrograde axonal transport in RGCs and a subsequent degeneration of these cells. In this model, at different time‐points after OHT induction (1, 3, 5, 8 and 15 days), the microglia exhibited different signs of activation, such as proliferation and migration to areas of damage, retraction, reorientation, and hyper‐ramification of their processes, soma thickening and the appearance of amoeboid‐ and rod‐like microglia with macrophagic capacity, related to RGC degeneration. All these changes were most intense at 3–5 days after OHT induction in the OHT eye. This was confirmed by the decreased expression of the purinergic receptor P2RY12, which would indicate higher microglial activation.In this model, at all time‐points after OHT induction, the activation of the macroglia (astrocytes and Müller cells) has also been demonstrated, showing morphological changes, as well as an overexpression of glial fibrillary acidic protein (GFAP).In this laser‐induced OHT model, an MHC‐II overexpression was observed in the microglia, astrocytes, and Müller cells, allowing these cells to induce a T‐cell mediated immune response.Significant changes in the expression of proinflammatory (IL‐1β, IL‐6, INF‐γ, IL‐17), anti‐inflammatory (IL‐4, IL‐10) and myokines (Fractalkine, BDNF, VEGF) cytokines were also observed.The same changes in glial cells (microglia, astrocytes and Müller cells) as well as in the expression of different cytokines and myokines were observed in the contralateral normotensive eyes at the different time points after OHT induction although with a lower intensity.Based on the alterations found in the contralateral eye, it can be concluded that this eye should not be used as a control eye in experimental models of unilateral glaucoma. Changes in contralateral normotensive eyes could exhibit the initial events of glaucomatous neurodegeneration, probably mediated by inflammatory mechanisms. Therefore, studies focusing on contralateral eyes could improve our understanding of glaucomatous pathophysiology. The study of the contralateral eye appears to have the potential for discovering points of intervention to which future neuroprotective therapeutics can be directed.