Intraocular pressure reduction in glaucoma: Does every mmHg count?

Outcomes and baseline predictors of failure in primary standalone Xen45 gel stent vs trabeculectomy for glaucoma

PURPOSE

To compare safety, effectiveness and baseline predictors of failure in standalone primary Xen45 gel stent (Xen) vs trabeculectomy (Trab) in glaucoma.

DESIGN

Retrospective study SUBJECTS: Subjects that underwent primary Xen or Trab augmented by mitomycin-C with at least 12 months follow-up.

METHODS

Multinational observational study of eyes in the Fight Glaucoma Blindness international registry MAIN OUTCOME MEASURES: The primary outcome was success at 12 months defined by IOP reduction ≥ 20% from baseline and ≤ threshold IOPs of 15mmHg, 18mmHg and 21mmHg with (qualified) or without (complete) medications and without secondary glaucoma surgery. Multivariable mixed effects cox regression models were used to identify risk factors for failure in each cohort.

RESULTS

701 eyes (Xen, 308; Trab, 393) of 596 subjects were included with baseline IOP being significantly higher (22.4 vs 19.9 mmHg, p < 0.001) and baseline medications significantly lower in the Xen vs the Trab group (2.9 vs 3.4, p <0.001). Baseline visual field (VF) mean deviation (MD) was less severe in the Xen group (-9.47 vs -13.04 dB, p < 0.001). The proportion of complete surgical success was significantly lower in the Xen vs Trab group across the three upper IOP limits at 12 months; 32% vs 52% at 15mmHg, 37% vs 54% at 18mmHg, and 39% vs 55% at 21mmHg (p < 0.001). The incidence of post-operative numerical and symptomatic hypotony was lower in the Xen vs Trab group. In the Xen cohort, a higher failure rate was associated with Asian ethnicity (HR, 1.97; 95% CI, 1.03-3.79) and use of oral acetazolamide at baseline (HR, 1.74; 1.13-2.70), while a lower failure rate was associated with diagnosis of ocular hypertension/open angle glaucoma suspect (HR, 0.52; 0.28-0.94) and secondary open angle glaucoma (HR, 0.45; 0.25-0.8). Exposure to prostaglandin analogue was associated with greater failure in the Trab group (HR, 2.66; 1.18-6.01).

CONCLUSIONS

There was significantly greater complete success at 12 months across all complete success definitions for Trab compared to Xen, while the rate of post-operative hypotony was significantly lower in Xen group. Asian ethnicity and use of oral acetazolamide at baseline were associated with greater failure in Xen, while exposure to prostaglandin analogue was associated with greater failure in Trab patients. Such baseline predictors of success and failure may help guide patient selection for subconjunctival minimally invasive glaucoma surgery in patients undergoing surgical intervention.

Increased late-onset glaucoma risk following vitrectomy for macular pucker or hole

OBJECTIVES

The long-term risk of developing glaucoma after vitrectomy remains uncertain. This retrospective population-based cohort study aimed to explore this risk following vitrectomy for macular pucker or hole.

METHODS

Utilizing Taiwan's National Health Insurance Research Database (NHIRD), we included patients who were older than 18 years and had undergone vitrectomy surgery between 2011 and 2019. Exclusions were made for patients with prior diagnoses of glaucoma, congenital or secondary glaucoma, as well as those who had received previous vitreoretinal treatments or had undergone multiple vitrectomies.

RESULTS

After an average follow-up period of 51 and 53 months respectively for the vitrectomized and non-vitrectomized group, our results showed a relative risk of 1.71 for glaucoma development in the vitrectomized group. Higher adjusted hazard ratios were also observed for open-angle glaucoma and normal tension glaucoma. Increased risks were associated with male sex, obstructive sleep apnoea, and migraine. In the subgroup analysis, phakic eyes at baseline and those who had undergone cataract surgery post-vitrectomy were associated with a lower risk of glaucoma development during follow-up. Among all glaucoma events, pseudophakic status at baseline had the shortest interval to glaucoma development following vitrectomy.

CONCLUSIONS

These findings underscore the potential relationship between vitrectomy and glaucoma onset, emphasizing the need for vigilant monitoring and early detection of glaucoma in post-vitrectomy patients.

Genes as drugs for glaucoma: latest advances

PURPOSE OF REVIEW

To provide the latest advances on the future use of gene therapy for the treatment of glaucoma.

RECENT FINDINGS

In preclinical studies, a number of genes have been shown to be able to reduce elevated intraocular pressure (IOP), and to exert neuroprotection of the retinal ganglion cells. These genes target various mechanisms of action and include among others: MMP3 , PLAT, IκB, GLIS, SIRT, Tie-2, AQP1. Some of these as well as some previously identified genes ( MMP3, PLAT, BDNF, C3, TGFβ, MYOC, ANGPTL7 ) are starting to move onto drug development. At the same time, progress has been made in the methods to deliver and control gene therapeutics (advances in these areas are not covered in this review).

SUMMARY

While preclinical efforts continue in several laboratories, an increasing number of start-up and large pharmaceutical companies are working on developing gene therapeutics for glaucoma ( Sylentis, Quetera/Astellas, Exhaura, Ikarovec, Genentech, Regeneron, Isarna, Diorasis Therapeutics ). Despite the presence of generic medications to treat glaucoma, given the size of the potential world-wide market (∼$7B), it is likely that the number of companies developing glaucoma gene therapies will increase further in the near future.

Novel micellar CB2 receptor agonist with anti-inflammatory action for treating corneal alkali burns in a mouse model

Introduction: Moderate corneal alkali burns such as those sustained from accidental exposure to household chemicals are treated with topical corticosteroids. Side effects include increased intraocular pressure and slowing of wound healing. Here, we compare the effects of a cannabinoid receptor 2 (CB2r) agonist, TA-A001, that is involved in wound healing with that of the corticosteroid, prednisolone. Methods: TA-A001 was encapsulated with a polymeric micelle comprising polyvinylpyrrolidone: polylactide block copolymers referred to as SmartCelle™ to allow delivery of the very hydrophobic drug. Mouse corneas were given moderate alkali burns. Different doses of TA-A001 of 0.125%, 0.25% and 0.5% were used to treat the burns in comparison to the corticosteroid, prednisolone. Results: TA-A001 at 0.25% and 0.5% allowed for faster wound closure. However, the higher 0.5% dose also induced unwanted neovascularization. By comparison, burned corneas treated with prednisolone showed slower healing as well as disorganization of the cornea. Although 0.25% TA-A001 appeared to produce the most-optimal responses, this dose resulted in marked expression of the macrophage chemoattractant protein, MCP-1. However, there was also an increase in CD163 positive stained M2 anti-inflammatory macrophages in the TA-A001 corneas. TA-A001 treated corneas showed the presence of sensory nerve fibers throughout the corneal epithelium including the superficial cell layers as did Substance P staining. Discussion: We found that TA-A001 at the 0.25% doses was able to modulate inflammation resulting from a moderate alkali burn to the cornea. With more extensive testing, TA-A001 might prove to be a potential alternative to corticosteroids for treating alkali burns or other causes of corneal inflammation.

Influence of unilateral eyelid spasms and botulinum toxin treatment on intraocular pressure measured by transpalpebral tonometer

PURPOSE

Eyelid spasms might be associated with elevated intraocular pressure (IOP) in hemifacial spasm (HFS) patients. IOP assessment using a Goldmann applanation tonometer (GAT) is often compromised by eyelid spasms. This study aimed to assess the effect of HFS on IOP measurements using the transpalpebral tonometer Diaton® before and after treatment with botulinum toxin type A (BTX-A) and compared Diaton® and GAT measurements after treatment with BTX-A.

METHODS

IOP measurements were obtained with Diaton® in 27 patients with moderate-to-severe HFS before and after treatment with BTX-A. After treatment, the IOP was also measured using GAT and the results were compared with the ones measured with a Diaton®. The patients underwent automated perimetry, OCT, and pachymetry for screening to glaucoma.

RESULTS

Mean IOP with Diaton® was 11 ± 3.42 mmHg before treatment in the affected eye and 9 ± 2.98 mmHg in the contralateral eye. This difference was statistically significant (P = 0.012). However, after treatment with BTX-A, no interocular difference was found in IOP obtained with Diaton® (P = 0.204) or GAT (P = 0.971). Comparison between GAT and Diaton® measurements showed no significant differences after BTX-A treatment between the affected (P = 0.212) and contralateral eye (P = 0.971).

CONCLUSIONS

A significant reduction in IOP measurements on the affected side of HFS patients was observed after treatment with BTX-A, demonstrating that eyelid spasms may increase the IOP. No significant difference was observed between Diaton® and GAT measurements after the application of BTX-A. No differences were found in automated perimetry, OCT, and CCT when comparing affected eyes with contralateral eyes.

Swept-Source Anterior Segment Optical Coherence Tomography Imaging and Quantification of Bleb Parameters in Glaucoma Filtration Surgery

This paper describes a technique for using swept-source anterior segment optical coherence tomography (AS-OCT) to visualize internal bleb microstructure and objectively quantify dimensions of the scleral flap and trabeculo-Descemet window (TDW) in non-penetrating glaucoma filtration surgery (GFS). This was a cross-sectional study of 107 filtering blebs of 67 patients who had undergone deep sclerectomy surgery at least 12 months prior. The mean post-operative follow-up duration was 6.5 years +/- 4.1 [standard deviation (SD)]. The maximal bleb height was significantly greater in the complete success (CS) blebs compared to the qualified success (QS) and failed (F) blebs (1.48 vs. 1.17 vs. 1.10 mm in CS vs. QS vs. F, one-way ANOVA, p < 0.0001). In a subcohort of deep sclerectomy blebs augmented by intraoperative Mitomycin-C, the trabeculo-Descemet window was significantly longer in the complete success compared to the qualified success group (613.7 vs. 378.1 vs. 450.8 µm in CS vs. QS vs. F, p = 0.004). The scleral flap length, thickness, and width were otherwise similar across the three outcome groups. The quantification of surgical parameters that influence aqueous outflow in non-penetrating GFS can help surgeons better understand the influence of these structures on aqueous outflow and improve surgical outcomes.

Retinal ganglion cell repopulation for vision restoration in optic neuropathy: a roadmap from the RReSTORe Consortium

Retinal ganglion cell (RGC) death in glaucoma and other optic neuropathies results in irreversible vision loss due to the mammalian central nervous system's limited regenerative capacity. RGC repopulation is a promising therapeutic approach to reverse vision loss from optic neuropathies if the newly introduced neurons can reestablish functional retinal and thalamic circuits. In theory, RGCs might be repopulated through the transplantation of stem cell-derived neurons or via the induction of endogenous transdifferentiation. The RGC Repopulation, Stem Cell Transplantation, and Optic Nerve Regeneration (RReSTORe) Consortium was established to address the challenges associated with the therapeutic repair of the visual pathway in optic neuropathy. In 2022, the RReSTORe Consortium initiated ongoing international collaborative discussions to advance the RGC repopulation field and has identified five critical areas of focus: (1) RGC development and differentiation, (2) Transplantation methods and models, (3) RGC survival, maturation, and host interactions, (4) Inner retinal wiring, and (5) Eye-to-brain connectivity. Here, we discuss the most pertinent questions and challenges that exist on the path to clinical translation and suggest experimental directions to propel this work going forward. Using these five subtopic discussion groups (SDGs) as a framework, we suggest multidisciplinary approaches to restore the diseased visual pathway by leveraging groundbreaking insights from developmental neuroscience, stem cell biology, molecular biology, optical imaging, animal models of optic neuropathy, immunology & immunotolerance, neuropathology & neuroprotection, materials science & biomedical engineering, and regenerative neuroscience. While significant hurdles remain, the RReSTORe Consortium's efforts provide a comprehensive roadmap for advancing the RGC repopulation field and hold potential for transformative progress in restoring vision in patients suffering from optic neuropathies.

Intraocular Pressure and Rates of Macular Thinning in Glaucoma

PURPOSE

To evaluate the effect of intraocular pressure (IOP) on the rates of macular thickness (ganglion cell layer [GCL] and ganglion cell-inner plexiform layer [GCIPL]) change over time measured by spectral-domain (SD) OCT.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Overall, 451 eyes of 256 patients with primary open-angle glaucoma.

METHODS

Data were extracted from the Duke Ophthalmic Registry, a database of electronic medical records of patients observed under routine clinical care at the Duke Eye Center, and satellite clinics. All records from patients with a minimum of 6 months of follow-up and at least 2 good-quality Spectralis SD-OCT macula scans were included. Linear mixed models were used to investigate the relationship between average IOP during follow-up and rates of GCL and GCIPL thickness change over time.

MAIN OUTCOME MEASURES

The effect of IOP on the rates of GCL and GCIPL thickness loss measured by SD-OCT.

RESULTS

Eyes had a mean follow-up of 1.8 ± 1.3 years, ranging from 0.5 to 10.2 years. The average rate of change for GCL thickness was -0.220 μm/year (95% confidence interval [CI], -0.268 to -0.172 μm/year) and for GCIPL thickness was -0.231 μm/year (95% CI, -0.302 to -0.160 μm/year). Each 1-mmHg higher mean IOP during follow-up was associated with an additional loss of -0.021 μm/year of GCL thickness (P = 0.001) and -0.032 μm/year of GCIPL thickness (P = 0.001) after adjusting for potentially confounding factors, such as baseline age, disease severity, sex, race, central corneal thickness, and follow-up time.

CONCLUSIONS

Higher IOP was significantly associated with faster rates of GCL and GCIPL loss over time measured by SD-OCT, even during relatively short follow-up times. These findings support the use of SD-OCT GCL and GCIPL thickness measurements as structural biomarkers for the evaluation of the efficacy of IOP-lowering therapies in slowing down the progression of glaucoma.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Availability of Physical Activity Tracking Data from Wearable Devices for Glaucoma Patients

Physical activity has been found to potentially modulate glaucoma risk, but the evidence remains inconclusive. The increasing use of wearable physical activity trackers may provide longitudinal and granular data suitable to address this issue, but little is known regarding the characteristics and availability of these data sources. We performed a scoping review and query of data sources on the availability of wearable physical activity data for glaucoma patients. Literature databases (PubMed and MEDLINE) were reviewed with search terms consisting of those related to physical activity trackers and those related to glaucoma, and we evaluated results at the intersection of these two groups. Biomedical databases were also reviewed, for which we completed database queries. We identified eight data sources containing physical activity tracking data for glaucoma, with two being large national databases (UK BioBank and All of Us) and six from individual journal articles providing participant-level information. The number of glaucoma patients with physical activity tracking data available, types of glaucoma-related data, fitness devices utilized, and diversity of participants varied across all sources. Overall, there were limited analyses of these data, suggesting the need for additional research to further investigate how physical activity may alter glaucoma risk.

Comparison of the TONOVET Plus®, TonoVet®, and Tono-Pen Vet™ tonometers in normal cats and cats with glaucoma

OBJECTIVES

To determine the accuracy, precision, and clinical applicability of the ICare® TONOVET Plus (TVP) in cats.

ANIMALS AND PROCEDURES

IOP readings obtained with the TVP were compared to values obtained concurrently with the original TONOVET (TV01) and Tono-Pen Vet™ (TP) in 12 normal cats (24 eyes) and 8 glaucomatous LTBP2-mutant cats (13 eyes) in vivo. Reproducibility of TVP readings was also assessed for three observers in the above cats. The anterior chambers of five different normal cat eyes were cannulated ex vivo. IOP was measured with the TVP, TV01, and TP at manometric IOPs ranging from 5 to 70 mmHg. Data were analyzed by linear regression, ANOVA and Bland-Altman plots. ANOVA was used to assess reproducibility of TVP readings obtained by different observers and an ANCOVA model controlled for variation of individual cats. p < .05 was considered significant.

RESULTS

TVP values strongly correlated with TV01 values (y = 1.045x + 1.443, R2  = .9667). The TP significantly underestimated IOP relative to the TVP and TV01, particularly at high IOP. IOP values obtained by 1 observer were significantly higher (~1 mmHg average) compared to the other 2 observers via ANCOVA analysis (p = .0006479 and p = .0203). Relative to manometry, the TVP and TV01 were significantly more accurate (p < .0001) and precise (p < .0070) than the TP in ex vivo eyes.

CONCLUSIONS

IOP readings obtained with the TVP and TV01 are broadly interchangeable between models and between observers, but subtle differences may be important in a research context. TP readings vastly underestimate high IOP in feline glaucoma.

Efficacy and safety of latanoprost/timolol fixed combination dosed twice daily compared to once daily in patients with primary open angle glaucoma

AIM

To evaluate whether latanoprost/timolol fixed combination (LTFC) dosed twice daily may provide further intraocular pressure (IOP) reduction and evaluate the safety profile at this dose.

METHODS

This is an open-labeled, randomized, prospective crossover study on fourty primary open angle glaucoma patients. Two weeks of washout period were followed by randomization to either once daily (OD, group A) or twice daily dosing (BD, group B) of LTFC for 4wk. After another 2-week washout period, the patients' treatment dose was crossed-over for another 4wk. IOP reduction alongside ocular and systemic side effects were evaluated.

RESULTS

Mean baseline IOP was 18.57±2.93 and 17.8±3.01 mm Hg before OD and BD dose respectively, (P=0.27). Mean IOP after BD dose was statistically lower (12.49±1.59 mm Hg) compared to OD (13.48±1.81 mm Hg, P=0.017). Although IOP reduction after BD dose was more (5.32±3.24 mm Hg, 29.89%) than after OD dosing (5.04 mm Hg, 27.14%), it did not reach statistical significance (P=0.68). Patients switched from OD to BD (group A) showed mean IOP reduction by 0.69 mm Hg [95% confidence interval (CI): -0.09 to 1.48 mm Hg, P=0.078]; but patients switched from BD to OD (group B) had significantly higher mean IOP by 1.25 mm Hg (95%CI: -2.04 to -0.46 mm Hg, P=0.006). BD dose had more ocular side effects albeit mild.

CONCLUSION

Mean IOP after LTFC dosed twice daily is statistically lower, with additional mild side effects.

From bench to behaviour: The role of lifestyle factors on intraocular pressure, neuroprotection, and disease progression in glaucoma

Current glaucoma management centres on intraocular pressure (IOP) reduction through pharmacological and surgical therapy. Despite broad interest in active management of glaucoma through lifestyle modifications, such recommendations have yet to be incorporated into standards of treatment. In this review, noteworthy preclinical studies and their translations in clinical populations are discussed to evaluate the roles of lifestyle factors in lowering IOP, offering neuroprotection, and/or slowing disease progression in those with open-angle glaucoma. Current literature suggests that aerobic exercise may be associated with neuroprotection and decreased disease progression. Mindfulness is associated with IOP reductions and neuroprotection. Caffeine is associated with mild, transient IOP elevations of uncertain significance. Nicotinamide supplementation is associated with neuroprotection and short-term visual function improvement. This review also highlights knowledge gaps regarding these factors and opportunities to strengthen our understanding of their role in glaucoma, including future preclinical studies that elucidate underlying mechanisms and clinical studies with additional functional endpoints and longer follow-up.

Molecular genetics of primary open-angle glaucoma

Glaucoma is a series of linked optic diseases resulting in progressive vision loss and total blindness due to the acquired loss of retinal ganglion cells. This harm to the optic nerve results in visual impairment and, ultimately, total blindness if left untreated. Primary open-angle glaucoma (POAG) is the most frequent variety within the large family of glaucoma. It is a multifaceted and heterogeneous condition with several environmental and genetic variables aiding in its etiology. By 2040, there will be 111.8 million glaucoma patients globally, with Asia and Africa accounting for the vast majority. The goal of this review is to elaborate on the role of genes (nuclear and mitochondrial) as well as their variants in the pathogenesis of POAG. PubMed and Google Scholar databases were searched online for papers until September 2022. Prevalence and inheritance patterns vary significantly across different ethnic and geographic populations. Numerous causative genetic loci may exist; however, only a few have been recognized and characterized. Further investigation into the genetic etiology of POAG is expected to uncover novel and intriguing causal genes, allowing for a more precise pathogenesis pattern of the disease.

Twenty Novel MicroRNAs in the Aqueous Humor of Pseudoexfoliation Glaucoma Patients

The microRNAs (miRNAs) are short non-coding RNAs (19-25 nt) that regulate the level of gene expression at the post-transcriptional stage. Altered miRNAs expression can lead to the development of various diseases, e.g., pseudoexfoliation glaucoma (PEXG). In this study, we assessed the levels of miRNA expression in the aqueous humor of PEXG patients using the expression microarray method. Twenty new miRNA molecules have been selected as having the potential to be associated with the development or progression of PEXG. Ten miRNAs were downregulated in PEXG (hsa-miR-95-5p, hsa-miR-515-3p, hsa-mir-802, hsa-miR-1205, hsa-miR-3660, hsa-mir-3683, hsa -mir-3936, hsa-miR-4774-5p, hsa-miR-6509-3p, hsa-miR-7843-3p) and ten miRNAs were upregulated in PEXG (hsa-miR-202 -3p, hsa-miR-3622a-3p, hsa-mir-4329, hsa-miR-4524a-3p, hsa-miR-4655-5p, hsa-mir-6071, hsa-mir-6723-5p, hsa-miR-6847-5p, hsa-miR-8074, and hsa-miR-8083). Functional analysis and enrichment analysis showed that the mechanisms that can be regulated by these miRNAs are: extracellular matrix (ECM) imbalance, cell apoptosis (possibly retinal ganglion cells (RGCs)), autophagy, and elevated calcium cation levels. Nevertheless, the exact molecular basis of PEXG is unknown and further research is required on this topic.

Distribution and associated factors of intraocular pressure in the older population: Tehran Geriatric Eye Study

AIM

To determine the distribution and associated factors of intraocular pressure (IOP) in an Iranian elderly population 60 years of age and above.

METHODS

The present report is part of the Tehran Geriatric Eye study (TGES), a population-based cross-sectional study that was conducted on the residents of Tehran 60 years of age and above. The sampling was performed using multistage stratified random cluster sampling methods from 22 districts of Tehran, Iran. Demographic and history information, blood samples, and blood pressure were collected from all participants. Ocular examinations included measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, and slit-lamp biomicroscopy. The IOP was measured using Goldmann applanation tonometry (GAT). Corneal imaging and ocular biometry were performed using Pentacam AXL.

RESULTS

The data of 3892 eyes of 2124 individuals were analyzed for this report. The mean age of the study participants was 66.49±5.31y (range: 60 to 95y). The mean IOP was 15.2 mm Hg (95%CI: 15.1 to 15.4), 15.3 mm Hg (95%CI: 15.1 to 15.5) and 15.1 mm Hg (95%CI: 15.0 to 15.3) in all participants, males, and females, respectively. Of the study participants, 1.3% had an IOP of ≥20 mm Hg. The mean IOP increased from 15.1 mm Hg in the age group 60-64y to 16.3 mm Hg in the age group ≥80y. According to the final multiple GEE model, the IOP was statistically significantly higher in men than in women. All the studied age groups, except for the 75-79-year-old age group, had significantly higher IOP compared to the 60-64-year-old age group. The IOP was significantly higher in underweight compared to other body mass index groups. Moreover, the IOP had a statistically significant direct relationship with the mean corneal power (mean CP), central corneal thickness (CCT), and systolic blood pressure.

CONCLUSION

The present study presents the distribution of IOP in an Iranian elderly population. A higher IOP (within the range 14 to 17 mm Hg) is significantly associated with older age, male sex, high systolic blood pressure, increased mean CP, and CCT. These factors should be considered in the clinical interpretation of IOP.

Combined use of coenzyme Q10 and citicoline: A new possibility for patients with glaucoma

Glaucoma is the leading cause of irreversible blindness worldwide. Several risk factors have been involved in the pathogenesis of the disease. By now, the main treatable risk factor is elevated intraocular pressure. Nevertheless, some patients, whose intraocular pressure is considered in the target level, still experience a progression of the disease. Glaucoma is a form of multifactorial ocular neurodegeneration with complex etiology, pathogenesis, and pathology. New evidence strongly suggests brain involvement in all aspects of this disease. This hypothesis and the need to prevent glaucomatous progression led to a growing interest in the pharmacological research of new neuroprotective, non-IOP-lowering, agents. The aim of this paper is to report evidence of the usefulness of Coenzyme Q10 and Citicoline, eventually combined, in the prevention of glaucomatous neurodegeneration.

The Effect of Specific Techniques of Nasal Breathing [Pranayama] on Intra-Ocular Pressure in Normal Individuals, a Randomized Trial

PURPOSE

Glaucoma is an optic neuropathy where intraocular pressure is the only modifiable risk factor. Yoga is thought to adversely affect intra-ocular pressure (IOP) but we do not know if yogic breathing exercises can influence IOP. With this study, we aimed to determine the effect of specific nasal breathing techniques on intra-ocular pressure in normal individuals.

PATIENTS AND METHODS

One hundred and sixty-four normal subjects were randomly assigned to one of four specific breathing groups - right nostril breathing (RNB), left nostril breathing (LNB), alternate nostril breathing (ANB), normal breathing (NB). The IOP was measured in both eyes at baseline and following the breathing exercise; and the change was analyzed.

RESULTS

Eighty-five women and 79 men participated and there was no significant difference in baseline age or IOP between the groups. In RNB, IOP reduced significantly in both right and left eyes, from 14.3 ± 3.0mmHg to 13.9 ± 2.6mmHg, (p=0.022) and from 14.7 ± 3.2mmHg to 14.2 ± 3mmHg (p=0.016) respectively. In LNB, there was no significant IOP change in the right eye, whereas in the left eye, there was a significant reduction from 14.2 ± 2.7mmHg to 13.3 ± 2.5mmHg (p< 0.0001). There was no significant IOP change in ANB and NB.

CONCLUSION

Specific breathing techniques like right and left nostril breathing, alternate nostril breathing are safe and do not raise IOP in normal subjects. Additionally, right and left nostril breathing techniques have a beneficial effect of lowering IOP.

PLA-PEG Implant as a Drug Delivery System in Glaucoma Surgery: Experimental Study

Excessive postoperative scarring halts the effectiveness of glaucoma surgery and still remains a challenging problem. The purpose of this study was to develop a PLA-PEG-based drug delivery system with cyclosporine A or everolimus for wound healing modulation. Methods: PLA-PEG implants saturation with cyclosporine A or everolimus as well as their further in vitro release were analyzed. Anti-proliferative activity and cytotoxicity of the immunosuppressants were studied in vitro using human Tenon’s fibroblasts. Thirty-six rabbits underwent glaucoma filtration surgery with the application of sham implants or samples saturated with cyclosporine A or everolimus. The follow-up period was six months. A morphological study of the surgery area was also performed at seven days, one, and six months post-op. Results: PLA-PEG implants revealed a satisfactory ability to cumulate either cyclosporine A or everolimus. The most continuous period of cyclosporine A and everolimus desorption was 7 and 13 days, respectively. Immunosuppressants demonstrated marked anti-proliferative effect regarding human Tenon’s fibroblasts without signs of cytotoxicity at concentrations provided by the implants. Application of PLA-PEG implants saturated with immunosuppressants improved in vivo glaucoma surgery outcomes. Conclusions: Prolonged delivery of either cyclosporine A or everolimus by means of PLA-PEG implants represents a promising strategy of wound healing modulation in glaucoma filtration surgery.

iStent Trabecular Micro-bypass Stent Implantation Combined with Phacoemulsification for Open-Angle Glaucoma: A 2-Year Post-marketing Surveillance Study in Japan

Introduction

We report 2-year outcomes after implantation of iStent trabecular micro-bypass stent with phacoemulsification, in Japanese patients with mild–moderate open-angle glaucoma (OAG).

Methods

This was a 24-month, prospective, longitudinal, observational, post-marketing study conducted between July 2017 and September 2020. Patients consisted of adults with OAG on antiglaucoma medications who had cataract surgery combined with one iStent implantation. Outcome measures included intraocular pressure (IOP), antiglaucoma medications, treatment success rates (defined as eyes having lower IOP with same or reduced number of medications from baseline, or same IOP with reduced number of medications from baseline, and not requiring secondary glaucoma surgeries postoperatively), and safety. Outcomes were analyzed in the overall cohort and in glaucoma subtypes: primary OAG, normal-tension glaucoma, and exfoliative glaucoma.

Results

Overall, 232 eyes were enrolled. At 24 months, mean ± standard deviation IOP decreased from 17.6 ± 4.0 mmHg preoperatively to 14.3 ± 3.0 mmHg (p < 0.05), and mean number of medications reduced from 2.2 ± 1.2 preoperatively to 0.7 ± 1.2 (p < 0.05). Similar trends were observed across glaucoma subtypes. In the overall cohort, 96.7%, 95.3%, and 93.7% of patients achieved treatment success at 6, 12, and 24 months, respectively. There were 67.6% medication-free eyes at 24 months compared to 3.2% medication-free eyes preoperatively (p < 0.0001). Safety profile was favorable over the 2-year period.

Conclusions

Following iStent implantation with phacoemulsification, clinically relevant and statistically significant reductions in IOP and number of medications were observed in Japanese eyes with OAG over 2 years, with favorable safety profile. These reductions were observed across all glaucoma subtypes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02207-0.

Role of Oxidative Stress in Retinal Disease and the Early Intervention Strategies: A Review

The retina, owing to its cellular anatomy and physical location, is susceptible to generating reactive oxygen species (ROS), which are associated with several major retinal diseases. When ROS exceeds the body's natural antioxidants, the retina is in a state of oxidative stress, which is recognized as the pathogenesis of retinal diseases. The early stage of the pathogenic process is an adaptive change in which oxidative stress and endogenous defense mechanisms occur. If no treatment is applied, the retinal diseases will progress to the pathological stage with neuronal and vascular dysfunction or damage and even blindness. This review summarizes the role of oxidative stress in several common retinal diseases, including retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy, glaucoma, and retinopathy of prematurity. In addition, we discuss the early intervention strategies for these diseases. An outline is provided to identify potential intervention targets for further research. Early intervention for retinal diseases is necessary and urgent and may offer hope to improve patients' quality of life through functional vision.

Topical Medication Therapy for Glaucoma and Ocular Hypertension

Glaucoma is one of the most common causes of blindness, thus seriously affecting people’s health and quality of life. The topical medical therapy is as the first line treatment in the management of glaucoma since it is inexpensive, convenient, effective, and safe. This review summarizes and compares extensive clinical trials on the topical medications for the treatment of glaucoma, including topical monotherapy agents, topical fixed-combination agents, topical non-fixed combination agents, and their composition, mechanism of action, efficacy, and adverse effects, which will provide reference for optimal choice of clinical medication. Fixed-combination therapeutics offer greater efficacy, reliable security, clinical compliance, and tolerance than non-fixed combination agents and monotherapy agents, which will become a prefer option for the treatment of glaucoma. Meanwhile, we also discuss new trends in the field of new fixed combinations of medications, which may better control IOP and treat glaucoma.