The Application of Rho Kinase Inhibitors in the Management of Glaucoma.

Glaucoma is a chronic neurodegenerative disease that poses a significant threat of irreversible blindness worldwide. Current treatments for glaucoma focus on reducing intraocular pressure (IOP), which is the only modifiable risk factor. Traditional anti-glaucomatous agents, including carbonic anhydrase inhibitors, beta-blockers, alpha-2 agonists, and prostaglandin analogs, work by either improving uveoscleral outflow or reducing aqueous humor production. Rho kinase (ROCK) inhibitors represent a novel class of anti-glaucomatous drugs that have emerged from bench to bedside in the past decade, offering multifunctional characteristics. Unlike conventional medications, ROCK inhibitors directly target the trabecular meshwork outflow pathway. This review aims to discuss the mechanism of ROCK inhibitors in reducing IOP, providing neuroprotection, and preventing fibrosis. We also highlight recent studies and clinical trials evaluating the efficacy and safety of ROCK inhibitors, compare them with other clinical anti-glaucomatous medications, and outline future prospects for ROCK inhibitors in glaucoma treatment.

Unveiling Novel Structural Biomarkers for the Diagnosis of Glaucoma.

Glaucoma, a leading cause of irreversible blindness, poses a significant global health burden. Early detection is crucial for effective management and prevention of vision loss. This study presents a collection of novel structural biomarkers in glaucoma diagnosis. By employing advanced imaging techniques and data analysis algorithms, we now can recognize indicators of glaucomatous progression. Many research studies have revealed a correlation between the structural changes in the eye or brain, particularly in the optic nerve head and retinal nerve fiber layer, and the progression of glaucoma. These biomarkers demonstrate value in distinguishing glaucomatous eyes from healthy ones, even in the early stages of the disease. By facilitating timely detection and monitoring, they hold the potential to mitigate vision impairment and improve patient outcomes. This study marks an advancement in the field of glaucoma, offering a promising avenue for enhancing the diagnosis and possible management.

A multi-label transformer-based deep learning approach to predict focal visual field progression.

PURPOSE: Tracking functional changes in visual fields (VFs) through standard automated perimetry remains a clinical standard for glaucoma diagnosis. This study aims to develop and evaluate a deep learning (DL) model to predict regional VF progression, which has not been explored in prior studies. METHODS: The study included 2430 eyes of 1283 patients with four or more consecutive VF examinations from the baseline. A multi-label transformer-based network (MTN) using longitudinal VF data was developed to predict progression in six VF regions mapped to the optic disc. Progression was defined using the mean deviation (MD) slope and calculated for all six VF regions, referred to as clusters. Separate MTN models, trained for focal progression detection and forecasting on various numbers of VFs as model input, were tested on a held-out test set. RESULTS: The MTNs overall demonstrated excellent macro-average AUCs above 0.884 in detecting focal VF progression given five or more VFs. With a minimum of 6 VFs, the model demonstrated superior and more stable overall and per-cluster performance, compared to 5 VFs. The MTN given 6 VFs achieved a macro-average AUC of 0.848 for forecasting progression across 8 VF tests. The MTN also achieved excellent performance (AUCs ≥ 0.86, 1.0 sensitivity, and specificity ≥ 0.70) in four out of six clusters for the eyes already with severe VF loss (baseline MD ≤ - 12 dB). CONCLUSION: The high prediction accuracy suggested that multi-label DL networks trained with longitudinal VF results may assist in identifying and forecasting progression in VF regions.

The Role of Retinal Ganglion Cell Structure and Function in Glaucoma.

Glaucoma, a leading cause of irreversible blindness globally, primarily affects retinal ganglion cells (RGCs). This review dives into the anatomy of RGC subtypes, covering the different underlying theoretical mechanisms that lead to RGC susceptibility in glaucoma, including mechanical, vascular, excitotoxicity, and neurotrophic factor deficiency, as well as oxidative stress and inflammation. Furthermore, we examined numerous imaging methods and functional assessments to gain insight into RGC health. Finally, we investigated the current possible neuroprotective targets for RGCs that could help with future glaucoma research and management.

Overview of Recent Advances in Nano-Based Ocular Drug Delivery.

Ocular diseases profoundly impact patients' vision and overall quality of life globally. However, effective ocular drug delivery presents formidable challenges within clinical pharmacology and biomaterial science, primarily due to the intricate anatomical and physiological barriers unique to the eye. In this comprehensive review, we aim to shed light on the anatomical and physiological features of the eye, emphasizing the natural barriers it presents to drug administration. Our goal is to provide a thorough overview of various characteristics inherent to each nano-based drug delivery system. These encompass nanomicelles, nanoparticles, nanosuspensions, nanoemulsions, microemulsions, nanofibers, dendrimers, liposomes, niosomes, nanowafers, contact lenses, hydrogels, microneedles, and innovative gene therapy approaches employing nano-based ocular delivery techniques. We delve into the biology and methodology of these systems, introducing their clinical applications over the past decade. Furthermore, we discuss the advantages and challenges illuminated by recent studies. While nano-based drug delivery systems for ophthalmic formulations are gaining increasing attention, further research is imperative to address potential safety and toxicity concerns.

Biodegradable Polymer-Based Drug-Delivery Systems for Ocular Diseases.

Ocular drug delivery is a challenging field due to the unique anatomical and physiological barriers of the eye. Biodegradable polymers have emerged as promising tools for efficient and controlled drug delivery in ocular diseases. This review provides an overview of biodegradable polymer-based drug-delivery systems for ocular diseases with emphasis on the potential for biodegradable polymers to overcome the limitations of conventional methods, allowing for sustained drug release, improved bioavailability, and targeted therapy. Natural and synthetic polymers are both discussed, highlighting their biodegradability and biocompatibility. Various formulation strategies, such as nanoparticles, hydrogels, and microemulsions, among others, are investigated, detailing preparation methods, drug encapsulation, and clinical applications. The focus is on anterior and posterior segment drug delivery, covering glaucoma, corneal disorders, ocular inflammation, retinal diseases, age-related macular degeneration, and diabetic retinopathy. Safety considerations, such as biocompatibility evaluations, in vivo toxicity studies, and clinical safety, are addressed. Future perspectives encompass advancements, regulatory considerations, and clinical translation challenges. In conclusion, biodegradable polymers offer potential for efficient and targeted ocular drug delivery, improving therapeutic outcomes while reducing side effects. Further research is needed to optimize formulation strategies and address regulatory requirements for successful clinical implementation.

Updates on Biodegradable Formulations for Ocular Drug Delivery.

The complex nature of the ocular drug delivery barrier presents a significant challenge to the effective administration of drugs, resulting in poor therapeutic outcomes. To address this issue, it is essential to investigate new drugs and alternative delivery routes and vehicles. One promising approach is the use of biodegradable formulations to develop potential ocular drug delivery technologies. These include hydrogels, biodegradable microneedles, implants, and polymeric nanocarriers such as liposomes, nanoparticles, nanosuspensions, nanomicelles, and nanoemulsions. The research in these areas is rapidly growing. In this review, we provide an overview of recent updates in biodegradable formulations for ocular drug delivery over the past decade. Additionally, we examine the clinical use of different biodegradable formulations in various ocular diseases. The aim of this review is to gain a deeper understanding of potential future trends in biodegradable ocular drug delivery systems and to raise awareness of their potential for practical clinical application as a means of providing new treatment options for ocular diseases.

Erythropoietin in Glaucoma: From Mechanism to Therapy.

Glaucoma can cause irreversible vision loss and is the second leading cause of blindness worldwide. The disease mechanism is complex and various factors have been implicated in its pathogenesis, including ischemia, excessive oxidative stress, neurotropic factor deprivation, and neuron excitotoxicity. Erythropoietin (EPO) is a hormone that induces erythropoiesis in response to hypoxia. However, studies have shown that EPO also has neuroprotective effects and may be useful for rescuing apoptotic retinal ganglion cells in glaucoma. This article explores the relationship between EPO and glaucoma and summarizes preclinical experiments that have used EPO to treat glaucoma, with an aim to provide a different perspective from the current view that glaucoma is incurable.

The Latest Evidence of Erythropoietin in the Treatment of Glaucoma.

Erythropoietin (EPO) is a circulating hormone conventionally considered to be responsible for erythropoiesis. In addition to facilitating red blood cell production, EPO has pluripotent potential, such as for cognition improvement, neurogenesis, and anti-fibrotic, anti-apoptotic, anti-oxidative, and anti-inflammatory effects. In human retinal tissues, EPO receptors (EPORs) are expressed in the photoreceptor cells, retinal pigment epithelium, and retinal ganglion cell layer. Studies have suggested its potential therapeutic effects in many neurodegenerative diseases, including glaucoma. In this review, we discuss the correlation between glaucoma and EPO, physiology and potential neuroprotective function of the EPO/EPOR system, and latest evidence for the treatment of glaucoma with EPO.

Erythropoietin in Optic Neuropathies: Current Future Strategies for Optic Nerve Protection and Repair.

Erythropoietin (EPO) is known as a hormone for erythropoiesis in response to anemia and hypoxia. However, the effect of EPO is not only limited to hematopoietic tissue. Several studies have highlighted the neuroprotective function of EPO in extra-hematopoietic tissues, especially the retina. EPO could interact with its heterodimer receptor (EPOR/ßcR) to exert its anti-apoptosis, anti-inflammation and anti-oxidation effects in preventing retinal ganglion cells death through different intracellular signaling pathways. In this review, we summarized the available pre-clinical studies of EPO in treating glaucomatous optic neuropathy, optic neuritis, non-arteritic anterior ischemic optic neuropathy and traumatic optic neuropathy. In addition, we explore the future strategies of EPO for optic nerve protection and repair, including advances in EPO derivates, and EPO deliveries. These strategies will lead to a new chapter in the treatment of optic neuropathy.

Glaucoma diagnostic performance of macular ganglion cell complex thickness using regular and long axial length normative databases.

The risks of misdiagnosing a healthy individual as glaucomatous or vice versa may be high in a population with a large majority of highly myopic individuals, due to considerable morphologic variability in high myopic fundus. This study aims to compare the diagnostic ability of the regular and long axial length databases in the RS-3000 Advance SD-OCT (Nidek) device to correctly diagnose glaucoma with high myopia. Patients with high myopia (axial length ≥ 26.0 mm) in Chang Gung Memorial Hospital, Taiwan between 2015 and 2020 were included. Glaucoma was diagnosed based on glaucomatous discs, visual field defects and corresponding retinal nerve fiber layer defects. The sensitivity, specificity, diagnostic accuracy and likelihood ratios of diagnosing glaucoma via mGCC thickness in both superior/inferior and GChart mapping using the regular and long axial length normative databases. The specificity and diagnostic accuracy of mGCC thickness for distinguishing glaucomatous eyes from nonglaucomatous eyes among highly myopic eyes were significantly improved using the long axial length database (p = 0.046). There were also significant proportion changes in S/I mapping as well as GChart mapping (37.3% and 48.0%, respectively; p < 0.01) from abnormal to normal in the myopic normal eye group when using the long axial length normative database. The study revealed that clinicians could utilize a long axial length database to effectively decrease the number of false-positive diagnoses or to correctly identify highly myopic normal eyes misdiagnosed as glaucomatous eyes.

Accurate Identification of the Trabecular Meshwork under Gonioscopic View in Real Time Using Deep Learning.

PURPOSE: Accurate identification of iridocorneal structures on gonioscopy is difficult to master, and errors can lead to grave surgical complications. This study aimed to develop and train convolutional neural networks (CNNs) to accurately identify the trabecular meshwork (TM) in gonioscopic videos in real time for eventual clinical integrations. DESIGN: Cross-sectional study. PARTICIPANTS: Adult patients with open angle were identified in academic glaucoma clinics in both Taipei, Taiwan, and Irvine, California. METHODS: Neural Encoder-Decoder CNNs (U-nets) were trained to predict a curve marking the TM using an expert-annotated data set of 378 gonioscopy images. The model was trained and evaluated with stratified cross-validation grouped by patients to ensure uncorrelated training and testing sets, as well as on a separate test set and 3 intraoperative gonioscopic videos of ab interno trabeculotomy with Trabectome (totaling 90 seconds long, 30 frames per second). We also evaluated our model's performance by comparing its accuracy against ophthalmologists. MAIN OUTCOME MEASURES: Successful development of real-time-capable CNNs that are accurate in predicting and marking the TM's position in video frames of gonioscopic views. Models were evaluated in comparison with human expert annotations of static images and video data. RESULTS: The best CNN model produced test set predictions with a median deviation of 0.8% of the video frame's height (15.25 µm) from the human experts' annotations. This error is less than the average vertical height of the TM. The worst test frame prediction of this model had an average deviation of 4% of the frame height (76.28 µm), which is still considered a successful prediction. When challenged with unseen images, the CNN model scored greater than 2 standard deviations above the mean performance of the surveyed general ophthalmologists. CONCLUSIONS: Our CNN model can identify the TM in gonioscopy videos in real time with remarkable accuracy, allowing it to be used in connection with a video camera intraoperatively. This model can have applications in surgical training, automated screenings, and intraoperative guidance. The dataset developed in this study is one of the first publicly available gonioscopy image banks (https://lin.hs.uci.edu/research), which may encourage future investigations in this topic.

The Intraocular Pressure Lowering Effect of a Dual Kinase Inhibitor (ITRI-E-(S)4046) in Ocular Hypertensive Animal Models.

Purpose: The purpose of this study was to develop a preclinical compound, ITRI-E-(S)4046, a dual synergistic inhibitor of myosin light chain kinase 4 (MYLK4) and Rho-related protein kinase (ROCK), for reducing intraocular pressure (IOP). Methods: ITRI-E-(S)4046 is an amino-pyrazole derivative with physical and chemical properties suitable for ophthalmic formulation. In vitro kinase inhibition was evaluated using the Kinase-Glo Luminescent Kinase Assays. A comprehensive kinase selectivity analysis of ITRI-E-(S)4046 was performed using the KINOMEscan assay from DiscoverRx. The IOP reduction and tolerability of ITRI-E-(S)4046 were assessed in ocular normotensive rabbits, ocular normotensive non-human primates, and ocular hypertensive rabbits. In vivo studies were conducted to assess drug concentrations in ocular tissue. The adverse ocular effects of rabbit eyes were evaluated following the OECD405 guidelines. Results: ITRI-E-(S)4046 showed highly selective kinase inhibitory activity against ROCK1/2, MYLK4, and mitogen-activated protein kinase kinase kinase 19 (MAP3K19), with high specificity against protein kinase A, G, and C families. In ocular normotensive rabbits and non-human primates, the mean IOP reductions of 0.1% ITRI-E-(S)4046 eye drops were 29.8% and 28.5%, respectively. In hypertonic saline-induced and magnetic beads-induced ocular hypertensive rabbits, the mean IOP reductions of ITRI-E-(S)4046 0.1% eye drops were 46.9% and 22.0%, respectively. ITRI-E-(S)4046 was well tolerated with only temporary and minor signs of hyperemia. Conclusions: ITRI-E-(S)4046 is a novel type of highly specific ROCK1/2 and MYLK4 inhibitor that can reduce IOP in normotensive and hypertensive animal models. It has the potential to become an effective and well-tolerated treatment for glaucoma.

Characteristics of Optic Disc and Visual Field Changes in Patients with Thyroid-Associated Orbitopathy and Open-Angle Glaucoma.

This study aimed to characterize the changes in the visual field (VF) patterns and disc morphology of patients with thyroid-associated orbitopathy (TAO) and open-angle glaucoma (OAG). A retrospective review of the medical records at the Tri-Service General Hospital in Taiwan identified 396 eyes of 198 patients with thyroid-associated glaucoma. A final follow-up of VF examination in 140 eyes revealed 114 eyes with VF defects, indicating disease progression. The characteristics of and changes in disc morphology, optical coherence tomography findings, and VF defects were statistically analyzed. The most common VF defects at the initial diagnosis and the end of the follow-up period were inferior partial arcuate (17%) and paracentral (15%) defects, respectively. The most common VF defect in patients with unspecific disc signs was an unspecific scotoma (13%). The most common optic disc feature was disc cupping (51%), followed by parapapillary atrophy (48%). The most frequent location of nerve fiber layer thinning was the inferotemporal region (48%). VF defects showed a significantly more pronounced progression in the non-nerve fiber bundle group than in the nerve fiber bundle group (p < 0.001). This study details the characteristics and progression of disc morphology and VF defects in patients with TAO and OAG.

A Novel Procedure for the Management of Severe Hyphema after Glaucoma Filtering Surgery: Air-Blood Exchange under a Slit-Lamp Biomicroscopy.

Background and Objectives: This study introduces a novel office-based procedure involving air-blood exchange under a slit-lamp microscope for treatment of severe hyphema after filtering surgery. Materials and Methods: This retrospective study enrolled 17 patients (17 eyes) with a diagnosis of primary open-angle glaucoma with severe hyphema (≥4-mm height) after filtering surgery. All patients were treated with air-blood exchange under a slit-lamp using room air (12 patients) or 12% perfluoropropane (C3F8; five patients). Results: The procedures were successful in all 17 patients; they exhibited clear visual axes without complications during follow-up. In the room air group, the mean visual acuity (VA) and hyphema height significantly improved from 1.70 ± 1.07 LogMAR and 5.75 ± 1.14 mm before the procedure to 0.67 ± 0.18 LogMAR and 2.83 ± 0.54 mm after the procedure (p = 0.004; p < 0.001). In the C3F8 group, the mean VA showed a trend, though not significant, for improvement from 1.70 ± 1.10 LogMAR to 0.70 ± 0.19 LogMAR (p = 0.08); the mean hyphema height showed a trend for improvement from 5.40 ± 0.96 mm to 3.30 ± 0.45 mm. Compared with the C3F8 group, the room air group showed the same efficacy with a shorter VA recovery time. Conclusions: "Air-blood exchange under a slit-lamp using room air" is a convenient, rapid, inexpensive, and effective treatment option for severe hyphema after filtering surgery, and may reduce the risk of failure of filtering surgery.

Changes in Intraocular Pressure During Hemodialysis: A Meta-analysis.

PRCIS: Acetate dialysate causes elevation of intradialytic intraocular pressure (IOP) and contributed to the rise of IOP in the early years of hemodialysis (HD). Glaucoma, narrow-angle, or impaired aqueous outflow is another moderator causing a rise of intradialytic IOP. PURPOSE: Severe IOP elevation during HD has been described in many case reports. However, the results of primary studies are conflicting. This meta-analysis examined the impact of HD on IOP and explored the potential moderators. METHODS: Medline, PubMed, Embase, Web of Science, and Cochrane were systematically searched. Before-after studies reporting the change of IOP during HD were included. Intradialytic IOP changes were calculated based on 4 different definitions: highest-baseline, lowest-baseline, max-baseline, and end-baseline IOP difference. Standardized mean difference (SMD) was pooled using the random-effects model. RESULTS: Fifty-three studies involving 1903 participants and 2845 eyes were included. Overall data pooling showed no significant rise in intradialytic IOP. However, subgroup analysis showed an intradialytic IOP rise before 1986 (SMD: 0.593; 95% confidence interval: 0.169-1.018; max-baseline IOP difference as representative; most studies using acetate dialysate), no change between 1986 and 2005 (using both acetate and bicarbonate), and a decline after 2005 (SMD: -0.222; 95% confidence interval: -0.382 to -0.063; entirely using bicarbonate). Multivariable meta-regression showed only the type of dialysate, but not publication year or other potential factors, as a significant moderator. Glaucoma was found to be another significant moderator independent of the dialysate effect in bivariate meta-regression. CONCLUSIONS: IOP elevation in the early years of HD with the use of acetate dialysate is less of a clinical problem following its substitution with bicarbonate dialysate. However, physicians should still be cautious of potential IOP changes in the HD population with glaucoma.

Outcomes of Small Size Ahmed Glaucoma Valve Implantation in Asian Chronic Angle-Closure Glaucoma.

For chronic angle-closure glaucoma (ACG), Ahmed glaucoma valve (AGV) is a useful drainage device for intraocular pressure (IOP) control but there are few reports discussing the outcomes of small size AGV in adult patients. This retrospective study involved 43 Asian adult patients (43 eyes) with chronic ACG. All patients had undergone small size AGV insertion and were divided into anterior chamber (AC) group and posterior chamber (PC) group. In the AC group, tube was inserted through sclerectomy gap into the anterior chamber. In the PC group, tube was inserted into posterior chamber through a needling tract. Outcome measures were intraocular pressure (IOP), visual acuity, number of antiglaucoma medications, survival curve and incidence of complications. In total, 43 eyes of 43 patients, 24 in the AC group and 19 in the PC group, were reviewed. The mean follow-up period was 28.5 months (95% confidence interval: 25.5-31.4). Mean IOP had significantly decreased following AGV insertion. The Kaplan-Meier survival analysis demonstrated a probability of success at 24 months of 67.4% for qualified success and 39.5% for complete success. There were no significant differences between the AC and PC groups in terms of the mean IOP, cumulative probability of success, visual acuity change or antiglaucoma medication change, except IOP at 1-day and 1-month mean IOP. The most common complications noted was hyphema in the PC group. For adult chronic ACG patients, small size AGV insertion could be effective at lowering IOP. Besides, tube insertion into AC with sclerectomy may prevent the hypertensive phase in the early postoperative period.

AR12286 Alleviates TGF-ß-Related Myofibroblast Transdifferentiation and Reduces Fibrosis after Glaucoma Filtration Surgery.

Scar formation can cause the failure of glaucoma filtration surgery. We investigated the effect of AR12286, a selective Rho-associated kinase inhibitor, on myofibroblast transdifferentiation and intraocular pressure assessment in rabbit glaucoma filtration surgery models. Cell migration and collagen contraction were used to demonstrate the functionality of AR12286-modulated human conjunctival fibroblasts (HConFs). Polymerase chain reaction quantitative analysis was used to determine the effect of AR12286 on the production of collagen Type 1A1 and fibronectin 1. Cell migration and collagen contraction in HConFs were activated by TGF-ß1. However, compared with the control group, rabbit models treated with AR12286 exhibited higher reduction in intraocular pressure after filtration surgery, and decreased collagen levels at the wound site in vivo. Therefore, increased α-SMA expression in HConFs induced by TGF-ß1 could be inhibited by AR12286, and the production of Type 1A1 collagen and fibronectin 1 in TGF-ß1-treated HConFs was inhibited by AR12286. Overall, the stimulation of HConFs by TGF-ß1 was alleviated by AR12286, and this effect was mediated by the downregulation of TGF-ß receptor-related SMAD signaling pathways. In vivo results indicated that AR12286 thus improves the outcome of filtration surgery as a result of its antifibrotic action in the bleb tissue because AR12286 inhibited the TGF-ß receptor-related signaling pathway, suppressing several downstream reactions in myofibroblast transdifferentiation.

Antifibrotic role of low-dose mitomycin-c-induced cellular senescence in trabeculectomy models.

PURPOSE: We assessed whether mitomycin-C (MMC) has different antifibrotic mechanisms in trabeculectomy wound healing. METHODS: We identified 2 concentrations of MMC as "low-dose" by using WST-1 assay, Lactic dehydrogenase assay, and fluorescence-activated cell sorting flow cytometry. Senescence-associated ß-galactosidase (SA-ß-gal) and fibrotic gene expression was examined through immunocytochemistry, flow cytometry, real-time quantitative reverse transcription polymerase chain reaction, Western blotting, zymography, and modified scratch assay in vitro. In vivo, 0.1 mL of MMC or normal saline was injected to Tenon's capsule before trabeculectomy in a rabbit model. SA-ß-gal expression, apoptotic cell death, and collagen deposition in sites treated and not treated with MMC were evaluated using terminal dUTP nick end labeling assay and histochemical staining. Bleb function and intraocular pressure (IOP) levels were examined 3, 7, 14, 21, 28, and 35 days after trabeculectomy. RESULTS: In vitro, human Tenon's fibroblast (HTF) senescence was confirmed by observing cell morphologic change, SA-ß-gal accumulation, formation of senescence-associated heterochromatin, increased p16INK4a and p21CIP1/WAF1 expression, lower percentage of Ki-67-positive cells, and decreased COL1A1 release. Increased expression of α-SMA, COL1A1, and Smad2 signaling in TGF-ß1-induced stress fibers were passivated in senescent HTFs. In addition, cellular migration enhanced by TGF-ß1was inactivated. In vivo, histological examination indicated increased SA-ß-gal accumulation, lower apoptosis ratios, and looser collagen deposition in sites treated with 0.2 µM MMC. Low-dose MMC-induced cellular senescence prolonged trabeculectomy bleb survival and reduced IOP levels in a rabbit model. CONCLUSION: Low-dose MMC-induced cellular senescence is involved in the antifibrotic mechanism of trabeculectomy wound healing.