Recent advances in the management of neovascular glaucoma

Early postoperative bevacizumab for preventing neovascular glaucoma in phacovitrectomy for proliferative diabetic retinopathy

To evaluate the effectiveness of postoperative intravitreal bevacizumab (IVB) in preventing neovascular glaucoma (NVG) and identify associated risk factors in patients with proliferative diabetic retinopathy (PDR) undergoing phacovitrectomy. Patients with PDR who underwent phacovitrectomy were enrolled and categorized into two subgroups based on their postoperative treatment regimen: one group received IVB within 2 months following phacovitrectomy (Group 1); the other did not receive IVB during this period (Group 2). A comparative analysis evaluated the distinguishing characteristics of the two groups after 1:1 propensity score matching. Kaplan-Meier survival analysis was utilized to determine the incidence of NVG after phacovitrectomy. Multivariate analysis with the Cox proportional hazards model identified risk factors associated with NVG postphacovitrectomy. A total of 206 eyes of 206 patients were investigated in this study. NVG developed in 15 eyes (7.28%). The probabilities of NVG occurrence at 6, and 12 months following phacovitrectomy were 4.85%, and 7.28%, respectively. When comparing Groups 1 (n = 57) and 2 (n = 57), a significant difference was observed in the occurrence of NVG (P < 0.001). In Group 1, only one case of NVG (1.75%) were noted, whereas all other NVG cases occurred in Group 2 (9.39%). Male sex and high preoperative intraocular pressure (IOP) were associated with NVG occurrence following phacovitrectomy, and the administration of IVB within 2 months postphacovitrectomy demonstrated efficacy in preventing the development of NVG. Male sex and high preoperative IOP were associated with a higher incidence of NVG, and postoperative IVB had a protective effect against NVG occurrence.

Incidence and risk factor analysis of neovascular glaucoma following vitrectomy in patients with proliferative diabetic retinopathy

To investigate the incidence and risk factors for neovascular glaucoma (NVG) after vitrectomy in patients with proliferative diabetic retinopathy (PDR). Patients were categorized into two subgroups based on their treatment regimen: one group received vitrectomy only (Group 1), while the other received combined phacovitrectomy (Group 2). A comparative analysis was conducted to evaluate the distinguishing characteristics of the two groups. Kaplan-Meier survival analysis was used to determine the incidence of NVG following surgery. Furthermore, multivariate analysis using the Cox proportional hazards model was conducted to identify the risk factors associated with the development of NVG after surgery. A total of 484 eyes of 484 patients were included in the study. When comparing Group 1 with Group 2, a significant difference was observed in the occurrence of NVG. In Group 1, there were 10 cases of NVG (3.9%), whereas 29 cases of NVG occurred in Group 2 (12.71%). Male sex, high preoperative intraocular pressure (IOP), and combined phacovitrectomy were found to be associated with the occurrence of NVG following phacovitrectomy. Higher creatinine levels had a protective effect in preventing the development of NVG. Male sex, high preoperative IOP, and combined phacovitrectomy were associated with a high incidence of NVG. Explore strategies to prevent NVG is important when performing combined phacovitrectomy in patients with PDR.

Dose-Related Side Effects of Intravitreal Injections of Humanized Anti-Vascular Endothelial Growth Factor in Rats: Glial Cell Reactivity and Retinal Ganglion Cell Loss

Purpose

In a previous study, we documented that the Intravitreal injections (IVIs) of bevacizumab in rats caused a retinal inflammatory response. We now study whether the IVI of other humanized anti-VEGF: ranibizumab and aflibercept also cause an inflammatory reaction in the rat retina and if it depends on the dose administered. Finally, we study whether this reaction affects retinal ganglion cell (RGC) survival.

Methods

Albino Sprague-Dawley rats received a single IVI of 5 µL of PBS or ranibizumab or aflibercept at the concentration used in clinical practice (10 µg/µL or 40 µg/µL) or at a lower concentration (0.38 µg/µL and 1.5 µg/µL) calculated to obtain within the rat eye the same concentration as in the human eye in clinical practice. Others received a single 5 µL IVI of a polyclonal goat anti-rat VEGF (0.015 µg/µL) or of vehicle (PBS). Animals were processed 7 days or 1 month later. Retinal whole mounts were immunolabeled for the detection of microglial, macroglial, RGCs, and intrinsically photosensitive RGCs (ipRGCs). Fluorescence and confocal microscopy were used to examine retinal changes, and RGCs and ipRGCs were quantified automatically or semiautomatically, respectively.

Results

All the injected substances including the PBS induced detectable side effects, namely, retinal microglial cell activation and retinal astrocyte hypertrophy. However, there was a greater microglial and macroglial response when the higher concentrations of ranibizumab and aflibercept were injected than when PBS, the antibody anti-rat VEGF and the lower concentrations of ranibizumab or aflibercept were injected. The higher concentration of ranibizumab and aflibercept resulted also in significant RGC death, but did not cause appreciable ipRGC death.

Conclusions

The IVI of all the substances had some retinal inflammatory effects. The IVI of humanized anti-VEGF to rats at high doses cause important side effects: severe inflammation and RGC death, but not ipRGC death.

Long scleral tunnel technique for prevention of drainage tube-related complications during Ahmed glaucoma valve implantation

To evaluate the safety and efficacy of modified Ahmed glaucoma valve (AGV) implantation (long scleral tunnel technique) in the treatment of neovascularization glaucoma (NVG). This retrospective observational case series included 23 patients (23 eyes) diagnosed with NVG secondary to proliferative diabetic retinopathy from January 2020 to June 2021. All 23 cases received anti-vascular endothelial growth factor treatment. Then, after 3 to 7 days, these cases were treated with modified AGV implantation (long scleral tunnel technique) and were followed up for at least 6 months. The best corrected visual acuity, intraocular pressure, numbers of antiglaucoma medications used, and postoperative complications were observed at 1 week and 1, 3, and 6 months after treatment. With treatment, the mean best corrected visual acuity improved significantly (P < .001) from 1.62 ± 0.52 logMAR preoperatively to 1.29 ± 0.36 logMAR at the 6-month follow-up. The mean postoperative intraocular pressure was significantly lower than that before modified AGV implantation during follow-up period, decreasing from 45.48 ± 7.86 mm Hg preoperatively to 14.87 ± 1.96 mm Hg at 1 week, 18.39 ± 2.25 mm Hg at 1 month, 16.61 ± 1.47 mm Hg at 3 months, and 17.48 ± 1.38 mm Hg at 6 months (F = 256.646, P < .001). The median number of antiglaucoma medications used by patients also significantly decreased from 3 (3-4) preoperatively to 0 (0-1) at the 6-month follow-up after surgery (Z = -4.248, P < .001). Postoperative complications included hyphema in 2 cases and vitreous hemorrhage in 1 case, and all 3 patients achieved satisfactory recovery with treatment. No drainage tube-related complications occurred among our patients. Long scleral tunnel technique is a safe and effective surgical treatment for NVG with fewer drainage tube-related complications.

RISK FACTORS FOR SURGERY OR BLINDNESS IN NEOVASCULAR GLAUCOMA EYES TREATED WITH ANTI-VEGF INJECTIONS BY A RETINA SPECIALIST

PURPOSE

To determine baseline patient characteristics that predict the need for glaucoma surgery or blindness in eyes with neovascular glaucoma (NVG) despite intravitreal antivascular endothelial growth factor therapy.

METHODS

This is a retrospective cohort study of patients with NVG who had not previously received glaucoma surgery and were treated with intravitreal antivascular endothelial growth factor injections at the time of diagnosis, from September 8, 2011, to May 8, 2020, at a large, retina subspecialty practice.

RESULTS

Of 301 newly presenting NVG eyes, 31% required glaucoma surgery and 20% progressed to no light perception vision despite treatment. Patients with intraocular pressure >35 mmHg ( P < 0.001), two or more topical glaucoma medications ( P = 0.003), worse than 20/100 vision ( P = 0.024), proliferative diabetic retinopathy ( P = 0.001), eye pain or discomfort ( P = 0.010), and new patient status ( P = 0.015) at the time of NVG diagnosis were at a higher risk of glaucoma surgery or blindness regardless of antivascular endothelial growth factor therapy. The effect of panretinal photocoagulation was not statistically significant in a subgroup analysis of patients without media opacity ( P = 0.199).

CONCLUSION

Several baseline characteristics at the time of presentation to a retina specialist with NVG seem to portend a higher risk of uncontrolled glaucoma despite the use of antivascular endothelial growth factor therapy. Prompt referral of these patients to a glaucoma specialist should be strongly considered.

Neovascular Glaucoma: An Update

Neovascular glaucoma (NVG) is a severe type of secondary glaucoma with devastating complications and generally poor visual prognosis. NVG is defined by the development of pathological neovessels over the iris and the iridocorneal angle that can block the outflow of aqueous humor, causing elevation of intraocular pressure (IOP). The pathogenesis of NVG is, in most cases, associated with ischemia of the posterior segment, which is most frequently associated with proliferative diabetic retinopathy or central retinal vein occlusion. The advanced stages of NVG are by iris and angle neovascularization, angle, and extremely high IOP, accompanied by ocular pain and poor vision. The therapeutic approach of NVG is based on the reduction of retinal ischemia by panretinal photocoagulation. Intravitreal anti-VEGF administration can contribute to the regression of neovascularization, and topical and systemic medications may be necessary for IOP control. However, if medical treatment with these agents is not enough, surgical procedures may be required to lower IOP and prevent glaucomatous optic neuropathy. Early and prompt diagnosis, with identification of the underlying etiology, can improve IOP control and final visual outcome. The aim of this study is to review current knowledge of the pathogenesis and management of NVG.

Comparisons of the short-term effectiveness and safety of surgical treatment for neovascular glaucoma: a systematic review and network meta-analysis

OBJECTIVE

To compare the effectiveness and safety of the six interventions for neovascular glaucoma.

DESIGN

A systematic review and network meta-analysis.

METHODS

Randomised controlled trials and cohort studies which compared the six interventions in neovascular glaucoma were identified using the following databases searched up to 1 September 2020: PubMed, Cochrane Library, Embase and Web of Science. The quality assessment was conducted by using the Cochrane risk of bias tool and the Newcastle-Ottawa scale. The primary outcome measure was the weighted mean differences for intraocular pressure reduction. Secondary one was ORs for success rate. Outcome measures were reported with a 95% CI and p<0.05 was considered statistically significant. Network meta-analysis was performed using Stata V.15.0.

RESULTS

Twenty-three studies involving a total of 1303 patients were included. The types of surgical treatments included Ahmed glaucoma valve (AGV) implant surgery, AGV combined with intravitreal anti-vascular endothelial growth factor (AGV +IVAV), cyclophotocoagulation (CPC), cyclocryotherapy (CCT), trabeculectomy with mitomycin (Trab(MMC)) and Trab(MMC) combined with IVAV (Trab(MMC)+IVAV). Network meta-analysis showed that in comparison with AGV, AGV +IVAV (MD=4.74, 95% CI 1.04 to 8.45) and Trab(MMC)+IVAV (MD=6.19, 95% CI 0.99 to 11.40) showed a favourable effect in intraocular pressure reduction (IOPR) 6 months after surgery. Compared with CCT, AGV (OR=-0.17, 95% CI -0.53 to -0.05), AGV +IVAV (OR=-0.10, 95% CI -3.48 to -1.19), CPC (OR=-0.12, 95% CI -0.53 to -0.05), Trab(MMC) (OR=3.54, 95% CI 1.15 to 10.91) and Trab(MMC)+IVAV (OR=5.78, 95% CI 2.29 to 14.61) showed a superior impact in success rate. The order of efficacy as best intervention ranked as follows: Trab(MMC)+IVAV (IOPR 6 months after surgery, surface under the cumulative ranking (SUCRA)=88.1), CPC (IOPR 12 months after surgery, SUCRA=81.9), AGV +IVAV (IOPR 12 months after surgery, SUCRA=79.9) and AGV +IVAV (success rate, SUCRA=92.7). Adverse events were also summarised in detail.

CONCLUSION

In the treatment of neovascular glaucoma, AGV+IVAV and CPC were more effective in IOPR and success rate than the other four interventions. Additionally, AGV+IVAV is superior to CPC concerning the success rate in the long-term treatment. However, considering the limitations of this review, more high-quality trials, especially those surgical interventions not mentioned in this review, should be carried out in the future to further confirm the current findings.

Trabeculectomy for neovascular glaucoma in proliferative diabetic retinopathy, central retinal vein occlusion, and ocular ischemic syndrome: Surgical outcomes and prognostic factors for failure

PURPOSE

To evaluate the outcomes of trabeculectomy in the eyes with neovascular glaucoma (NVG), caused by proliferative diabetic retinopathy (PDR), central retinal vein occlusion (CRVO), and ocular ischemic syndrome (OIS).

METHODS

A retrospective review of NVG eyes that underwent trabeculectomy between 1991 and 2019. Complete success was defined as intraocular pressure (IOP) between 6 and 21 mmHg without antiglaucoma medications (AGM). The risk factors were analyzed by Cox's proportional hazard model.

RESULTS

The study included 100 eyes of 100 subjects with a mean age of 58 ± 9.8 years and a median follow-up of 1.27 years (interquartile range: 0.63, 2.27). The cause of NVG was PDR in 59 eyes (59%), CRVO in 25 eyes (25%), and OIS in 16 eyes (16%). Trabeculectomy with mitomycin-C was performed in 88 eyes and trabeculectomy in 12 eyes. The cumulative complete success probability of trabeculectomy in PDR was 50% (95% confidence interval [CI]: 38, 65) at 1 year, 8% (1, 46) at 3-5 years. In OIS, it was 64% (43, 96) from 1 to 5 years. In CRVO, it was 75% (59, 94) at 1 year, 45% (23, 86) from 2 to 5 years. The PDR was associated with a higher risk of surgical failure compared to OIS (P = 0.04) and CRVO (P = 0.004). Other significant risk factors were increasing age (P = 0.02), persistent neovascularization of iris (NVI) (P = 0.03), higher number of anti-vascular endothelial growth factor (VEGF) injections prior to trabeculectomy (P = 0.02), and delay in performing trabeculectomy (P = 0.02).

CONCLUSION

Compared to CRVO and OIS, the eyes with NVG secondary to PDR had poor success with trabeculectomy. Older age, persistent NVI, need for a higher number of anti-VEGF injections, and delayed surgery were associated with a higher risk for trabeculectomy failure.

Clinical profile and outcomes of neovascular glaucoma in the era of anti-vascular endothelial growth factor

Purpose:

To report the clinical profile and visual impairment in various stages of neovascular glaucoma (NVG) at a tertiary eye center in East India.

Methods:

The electronic medical records of the hospital database of patients with neovascular glaucoma seen between 2013 and 2020 were reviewed. Gonioscopic details were used to stratify patients into nonspecified NVG (Group 1), open-angle NVG (Group 2), and closed-angle NVG (Group 3). The clinical profile, angle features, cause of NVG, systemic associations, visual impairment, and blindness (defined as logarithm of the minimum angle of resolution, LogMar >1.3 at baseline and at final follow-up), and outcomes of medical/surgical interventions were compared between the three groups.

Results:

Of 846 eyes of 810 patients with NVG (Group 1, n = 564 eyes, Group 2, n = 61 eyes, and Group 3, n = 220 eyes), at baseline, the blindness rates in Groups 3 and 2 were 90 and 75%, respectively. The time from a previous intervention to the onset of NVG ranged from 3 to 5 months, while the median duration of NVG was about 4–4.5 months (0.03–120 months). Multivariate regression identified a longer duration of NVG as the only variable associated with poor final visual acuity.

Conclusion:

Visual morbidity by NVG remains as high as 75–90% in developing countries, even with the availability of anti-VEGFs and after improved management/investigative at all stages.

Simultaneous pars plana vitrectomy, panretinal photocoagulation, cryotherapy, and Ahmed valve implantation for neovascular glaucoma

AIM

To describe and evaluate the efficacy of Ahmed glaucoma valve implantation (AGV) combined with pars plana vitrectomy (PPV) in a single surgical act for the treatment of advanced neovascular glaucoma (NVG).

METHODS

Retrospective observational case series included 51 eyes from 50 patients with severe NVG treated with PPV, AGV, and panretinal photocoagulation and/or cryotherapy in a single surgical act during a 13-year period (2005-2018). Preoperative, intraoperative and postoperative data at day 1 and months 1, 3, 6, 21, and 24 were systematically collected. Definition of surgical success was stablished at IOP between 6 and 21 mm Hg with or without topical treatment.

RESULTS

Main indications for surgery were NVG secondary to proliferative diabetic retinopathy (39.2%) and central retinal vein occlusion (37.3%). Mean (±SD) preoperative IOP was 42.0±11.2 mm Hg decreasing to 15.5±7.1 mm Hg at 12mo and 15.8±9.1 mm Hg at 24mo of follow up. Cumulative incidence of success of IOP control was 76.0% at first postoperative month, reaching 88.3% at 6mo. Prevalence of successful IOP control at long term was 74.4% at 12mo and 71.4% at 24mo. Eye evisceration for unsuccessful NVG management was required in 1 case (2.0%).

CONCLUSION

Combination of AGV implantation and PPV in a single act may be a suitable option for severe forms of NVG in a case-by-case basis for effective IOP control and a complete panretinal photocoagulation.

Presentation, etiology and treatment outcome of neovascular glaucoma in Ekiti state, South Western Nigeria

Background

Neovascular glaucoma (NVG), a form of secondary glaucoma has varying causes across geographical locations.

Objective

The objective of this study was to determine the presentation, aetiology, and outcome of treatment of patients with NVG in a Nigerian tertiary hospital.

Method

A retrospective review of records of all cases of NVG seen over a 5year period was carried out. Demographic characteristics, presenting visual acuity and coexisting ocular and systemic conditions were noted. Data were analysed with Statistical Package for Social Sciences (SPSS) version 25.

Results

29 eyes of patients with NVG were analysed. Most of the patients (89.70%) presented with visual acuity less than 3/60 in the affected eye. All patients except one were treated with anti-glaucoma medications while only 9(31%) consented to and received anti-vascular endothelial growth factor. No patient had improvement in visual acuity despite resolution of other symptoms at 12week follow up.

Conclusion

NVG though not as common as other forms of glaucoma accounted for a large proportion of monocular blindness in the affected eyes at presentation. There is need for health promotion and education among our people on the need for early preventive eye check practices.

Neovascular glaucoma - A review

Neovascular glaucoma (NVG) is a sight-threatening secondary glaucoma characterized by appearance of new vessels over the iris and proliferation of fibrovascular tissue in the anterior chamber angle. Retinal ischemia is the common driving factor and common causes are central retinal vein occlusion, proliferative diabetic retinopathy, and ocular ischemic syndrome. The current rise in the prevalence of NVG is partly related to increase in people with diabetes. A high index of suspicion and a thorough anterior segment evaluation to identify the early new vessels on the iris surface or angle are essential for early diagnosis of NVG. With newer imaging modalities such as the optical coherence tomography angiography and newer treatment options such as the anti-vascular endothelial growth factor, it is possible to detect retinal ischemia early, tailor appropriate treatment, monitor disease progression, and treatment response. The management strategies are aimed at reducing the posterior segment ischemia, reduce the neovascular drive, and control the elevated intraocular pressure. This review summarizes the causes, pathogenesis, and differential diagnoses of NVG, and the management guidelines. We also propose a treatment algorithm of neovascular glaucoma.

Extracellular Matrix Remodeling in the Retina and Optic Nerve of a Novel Glaucoma Mouse Model

Simple Summary

Glaucoma is a leading cause of blindness worldwide, and increased age and intraocular pressure (IOP) are the major risk factors. Glaucoma is characterized by the death of nerve cells and the loss of optic nerve fibers. Recently, evidence has accumulated indicating that proteins in the environment of nerve cells, called the extracellular matrix (ECM), play an important role in glaucomatous neurodegeneration. Depending on its constitution, the ECM can influence either the survival or the death of nerve cells. Thus, the aim of our study was to comparatively explore alterations of various ECM molecules in the retina and optic nerve of aged control and glaucomatous mice with chronic IOP elevation. Interestingly, we observed elevated levels of blood vessel and glial cell-associated ECM components in the glaucomatous retina and optic nerve, which could be responsible for various pathological processes. A better understanding of the underlying signaling mechanisms may help to develop new diagnostic and therapeutic strategies for glaucoma patients.

Abstract

Glaucoma is a neurodegenerative disease that is characterized by the loss of retinal ganglion cells (RGC) and optic nerve fibers. Increased age and intraocular pressure (IOP) elevation are the main risk factors for developing glaucoma. Mice that are heterozygous (HET) for the mega-karyocyte protein tyrosine phosphatase 2 (PTP-Meg2) show chronic and progressive IOP elevation, severe RGCs loss, and optic nerve damage, and represent a valuable model for IOP-dependent primary open-angle glaucoma (POAG). Previously, evidence accumulated suggesting that glaucomatous neurodegeneration is associated with the extensive remodeling of extracellular matrix (ECM) molecules. Unfortunately, little is known about the exact ECM changes in the glaucomatous retina and optic nerve. Hence, the goal of the present study was to comparatively explore ECM alterations in glaucomatous PTP-Meg2 HET and control wild type (WT) mice. Due to their potential relevance in glaucomatous neurodegeneration, we specifically analyzed the expression pattern of the ECM glycoproteins fibronectin, laminin, tenascin-C, and tenascin-R as well as the proteoglycans aggrecan, brevican, and members of the receptor protein tyrosine phosphatase beta/zeta (RPTPβ/ζ) family. The analyses were carried out in the retina and optic nerve of glaucomatous PTP-Meg2 HET and WT mice using quantitative real-time PCR (RT-qPCR), immunohistochemistry, and Western blot. Interestingly, we observed increased fibronectin and laminin levels in the glaucomatous HET retina and optic nerve compared to the WT group. RT-qPCR analyses of the laminins α4, β2 and γ3 showed an altered isoform-specific regulation in the HET retina and optic nerve. In addition, an upregulation of tenascin-C and its interaction partner RPTPβ/ζ/phosphacan was found in glaucomatous tissue. However, comparable protein and mRNA levels for tenascin-R as well as aggrecan and brevican were observed in both groups. Overall, our study showed a remodeling of various ECM components in the glaucomatous retina and optic nerve of PTP-Meg2 HET mice. This dysregulation could be responsible for pathological processes such as neovascularization, inflammation, and reactive gliosis in glaucomatous neurodegeneration.

Various modalities for management of secondary angle closure neovascular glaucoma in diabetic eyes: 1-year comparative study

PURPOSE

To compare outcome of 4 methods for management of angle closure neovascular glaucoma (NVG) in diabetic eyes.

METHODS

Prospective comparative study, on 40 eyes (40 patients) with NVG. Patients were randomly assigned to group A (Trabeculectomy with MMC), B (Ahmed valve), C (Ex-Press Minishunt with MMC) or D (Diode cyclophotocoagulation). Patients were followed regularly for 1 year.

MAIN OUTCOME MEASURES

intraocular pressure (IOP), best corrected visual acuity (BCVA), central foveal thickness (CFT), intraoperative bleeding, postoperative complications and 2ry intervention.

RESULTS

Preoperative data were not significantly different between 4 groups. Postoperatively, there was significant drop in IOP in each group at each follow-up. Ahmed valve group showed least mean postoperative IOP and highest mean drop of the IOP at 1 day and 1 week postoperatively, while Ex-Press minishunt group had least mean postoperative IOP at 1 month and 3 months postoperatively. At 6 months and 1 year, there was no significant difference between 4 groups. BCVA was not significantly different between 4 groups. At 1 year, CFT was significantly lower in each of the 4 groups, and it was significantly the least in group A and highest in group D. Highest intraoperative bleeding was observed with trabeculectomy. Success rate was not significantly different among the 4 groups.

CONCLUSION

The 4 management options showed a significant long-term effect on IOP, and on long-terms there was no significant difference between them for IOP and BCVA. Trabeculectomy showed highest incidence of intraoperative bleeding, while cyclophotocoagulation showed none.

Trend of Neovascular Glaucoma in Taiwan: A 15-year Nationwide Population-based Cohort Study

PURPOSE

To determine the trends in epidemiological data in patients with neovascular glaucoma (NVG) in Taiwan.

METHODS

The data were obtained from the 2016 version of the Longitudinal Health Insurance Database, which contains data on two million randomly sampled patients. Patients with NVG diagnostic codes were enrolled in this study, after which we separated the study population according to different time periods. The demographic data, systemic and ocular comorbidities and treatments that were applied to manage NVG were collected from the database.

RESULTS

The overall age-standardized prevalence was 52.48 per 100,000 individuals, and the age-standardized incidence was 4.33 per 100,000 person-years in patients with NVG. In general, men had a higher prevalence and incidence, and the incidence was observed to fluctuate. The patients with the highest educational levels accounted for less than 5% of the NVG patients, and the patients with the highest income levels accounted for less than 15% of the NVG patients. Systemic comorbidities in NVG patients, especially metabolic syndrome, were observed to increase. The percentage of the patients receiving anti-vascular endothelial growth factor treatments increased by more than two-fold after 2008, whereas reductions in trabeculectomy and cyclodestruction procedures were observed.

CONCLUSION

The prevalence of NVG was observed to increase in men, and the incidence fluctuated during the study period. Furthermore, the systemic comorbidities, and the use of anti-vascular endothelial growth factor treatment increased; the latter may be associated with a decrease in the use of incisional glaucoma surgery for NVG in recent years.

A Comparative Study between Ultrasound Cycloplasty and Cyclocryotherapy for the Treatment of Neovascular Glaucoma

Purpose

To compare the clinical efficacy, safety, and histological effect between ultrasound cycloplasty (UCP) and cyclocryotherapy in the treatment of neovascular glaucoma.

Methods

Two groups of neovascular glaucoma patients who underwent two types of treatment, respectively, namely, 26 patients treated by UCP and 23 by cyclocryotherapy, were treated and observed during the clinical study for six months. The primary outcome was evaluated by the surgical success, which was defined as the intraocular pressure (IOP) reduction of greater than or equal to 20% from the baseline and the IOP value of greater than 5 mmHg at the last follow-up. The secondary outcome referred to pain relief, complications, and the mean of the IOP at each follow-up. In the animal experiment, 18 New Zealand rabbits were divided into two groups and treated by UCP and cyclocryotherapy, respectively. The changes in the tissues and in the expression of matrix metalloproteinase-1 (MMP-1) were observed immediately.

Results

The mean IOP baseline for the UCP and cyclocryotherapy groups was 54.6 ± 9.7 mmHg and 53.3 ± 11.7 mmHg, respectively. After six months of follow-up, the IOP value decreased to 30.3 ± 9.4 mmHg for the patients treated by UCP and to 30.4 ± 9.1 mmHg for those treated by cyclocryotherapy. The two groups achieved a satisfying success rate in the treatment of neovascular glaucoma of up to 70% at least. Vision impairment was observed in some patients treated with cyclocryotherapy, and these patients suffered from more complications and less pain relief than the patients who were treated with UCP. The histological study showed that the ciliary body was completely destroyed after cyclocryotherapy and that MMP-1 was found only in the ciliary muscle. After the UCP treatment, MMP-1 could still be found in the ciliary body, and only the double-layer epithelial cells presented with coagulative necrosis.

Conclusion

The UCP treatment and cyclocryotherapy both showed good efficacy in significantly reducing the IOP. However, the UCP treatment was safer with less postoperative complications and adverse effects. Thus, the overall treatment effect of the UCP was more efficient than that of cyclocryotherapy.

Risk Factors of Neovascular Glaucoma After 25-gauge Vitrectomy for Proliferative Diabetic Retinopathy with Vitreous Hemorrhage: A Retrospective Multicenter Study

Neovascular glaucoma (NVG) is a terminal severe complication in eyes with proliferative diabetic retinopathy (PDR), and PDR eyes with vitreous hemorrhage (VH) which undergo vitrectomy may have higher risk of postoperative NVG. The incidence and the prognostic factor of postoperative NVG after 25-gauge vitrectomy with advanced surgical options remain unclear. We retrospectively reviewed medical records of 268 eyes of 268 consecutive PDR patients with VH who underwent 25-gauge vitrectomy and 12 months follow-up at seven centers. Preoperative ocular factors (visual acuity, tractional retinal detachment, panretinal photocoagulation [PRP]), demographics and clinical factors (sex, age, diabetic duration, HbA1c, hypertension, anticoagulant medication, and kidney function), surgical procedures, and postoperative complications were compared between patients who developed postoperative NVG (9.3%) and those who did not. NVG eyes was significantly younger (P = 0.026), had shorter diabetic duration (P = 0.022), higher HbA1c (P = 0.028), absence of PRP (P = 0.039) and higher frequency of postoperative VH (P = 0.0075) than non-NVG eyes. Logistic regression analysis identified postoperative VH (P = 0.014), shorter diabetic duration (P = 0.029), and no PRP (P = 0.028) as prognostic factors for postoperative NVG. This multicenter study indicates that younger age, uncontrolled diabetes, no PRP, and postoperative VH are risk factors of post-vitrectomy NVG.

Intravitreal anti-vascular endothelial growth factor injection combined with panretinal photocoagulation for neovascular glaucoma in Indonesian patients with diabetes mellitus: a prospective study

BACKGROUND The aim of this study was to determine the levels of vascular endothelial growth factor (VEGF) in the aqueous humor and the effect of intravitreal anti-VEGF injection combined with panretinal photocoagulation (PRP) on the management in diabetes mellitus (DM) patients with neovascular glaucoma (NVG).  METHODS This study was a prospective, interventional study in DM patients with NVG. Paracentesis followed by intravitreal bevacizumab (IVB) injection was performed in all eyes. The concentration of VEGF obtained from paracentesis was measured. In week-1, the intraocular pressure (IOP), sectorial iris neovascularization (NVI), and visual acuity were documented, and management was continued with PRP laser over a period of 1 week. All parameters and additional interventions performed after PRP were also recorded.  RESULTS A total of 18 eyes from 17 patients were studied. The mean (SD) level of VEGF in the aqueous humor was 3,864 (1,468) pg/ml, and the mean (SD) of initial IOP was 39 (10.2) mmHg. There was a significant reduction in IOP in week-1 after the first intervention to 24.4 (8.0) mmHg (p = 0.001); however, at 2 weeks the IOP increased to 30.4 (6.7) mmHg. NVI showed significant regression in week-1 after IVB combined with PRP laser (p < 0.05). All eyes required additional glaucoma implants (14 eyes) and cyclocryotheraphy (4 eyes).  CONCLUSIONS In the eyes of diabetes patients with NVG, VEGF levels were high. With the use of IVB, the IOP was reduced, and NVI regressed; however, due to the severe stages of disease, all eyes required glaucoma surgery.

Efficacy of Ahmed Glaucoma Valve Implantation on Neovascular Glaucoma

To evaluate the efficacy of Ahmed glaucoma valve (AGV) implantation in treating neovascular glaucoma (NVG) and analyze the factors influencing the surgical success rate, a retrospective investigation of 59 NVG patients (66 eyes) who underwent AGV implantation was conducted at Jiangsu Province Hospital, China, from January 2014 to June 2018. Intraocular pressure (IOP), visual acuity, surgical success rates, medications, and complications were monitored at post-operative 1 day, 1 week, 1, 3, 6 and 12 months. Surgical success criteria were defined as 6 mm Hg < IOP < 21 mmHg with or without additional medications. Results showed average IOP was statistically significant between pre-operative visit and each follow-up visit (all P<0.05). At 12 months, the success rate was 66.7%. Multiple stepwise regression analysis suggested that age, panretinal photocoagulation (PRP), complications and hyphema were significant factors influencing the surgical success rate (all P<0.05). Thus, we conclude that AGV implantation is effective and safe for treatment of NVG. Surgical success is dependent on age, PRP, complications, and hyphema.

Contribution of the clock gene DEC2 to VEGF mRNA upregulation by modulation of HIF1α protein levels in hypoxic MIO-M1 cells, a human cell line of retinal glial (Müller) cells

PURPOSE

Clock genes are components of the molecular clock. Their malfunction is thought to increase the risk of numerous diseases, including cancer. Vascular endothelial growth factor (VEGF) has a pivotal role in angiogenesis, and its expression levels are controlled by clock genes in tumor cells. Ophthalmic diseases such as age-related macular degeneration, proliferative diabetic retinopathy, and neovascular glaucoma are also associated with abnormal angiogenesis followed by upregulation of VEGF in the eye. In the present study, we aimed to uncover the relationship between clock genes and VEGF in the eye.

STUDY DESIGN

Laboratory investigation METHODS: Oxygen-induced retinopathy (OIR) mice were prepared to mimic hypoxic conditions in the eye. Deferoxamine (DFO) was used to mimic hypoxic conditions in human Müller cell line MIO-M1 cells. Expression levels of mRNA and protein were quantified by quantitative reverse transcription polymerase chain reaction and Western blot analysis, respectively.

RESULTS

In the retinas of OIR mice, the expression levels of Vegf and the clock gene Dec2 increased transiently, and their temporal profiles were correlated. Knockdown of DEC2 resulted in a significant (26.7%) reduction of VEGF expression in MIO-M1 cells under hypoxia-mimicking conditions induced by DFO (P < .05). Levels of HIF1α protein were also reduced significantly, by 60.2%, in MIO-M1 cells treated with siRNA against the DEC2 gene (P < .05). Moreover, HIF1α levels showed a significant (2.5-fold) increase in MIO-M1 cells overexpressing DEC2 (P < .05).

CONCLUSION

DEC2 could upregulate retinal VEGF gene expression through modulation of HIF1α levels under hypoxic conditions.

Effectiveness of multiple therapeutic strategies in neovascular glaucoma patients: A PRISMA-compliant network meta-analysis

PURPOSE

Neovascular glaucoma (NVG) is a severe secondary glaucoma with uncontrolled intraocular pressure that leads to serious eye pain and vision loss. Presently, the therapeutic strategies for NVG are diverse, but the therapeutic effects are still not ideal. We performed a network analysis to assess the effect of multiple therapeutic strategies on the treatment of NVG patients.

METHODS

We searched public electronic databases through April 2017 using the following keywords "neovascular glaucoma," "iris neovascularization," "hemorrhagic glaucoma," and "random" without language restrictions. The outcome considered in the present analysis was treatment success rate. A network meta-analysis and multilevel mixed-effects logistic regression were used to compare regimens.

RESULTS

We included 27 articles assessing a total of 1884 NVG patients in our analysis. According to the network analysis, interferon and mitomycin plus trabeculectomy (94.9%), glaucoma valve implantation (86.9%), and iris photocoagulation plus trabeculectomy (81.9%) were the most likely to improve treatment success rate in NVG patients. The multilevel logistic regression analysis showed that glaucoma valve, bevacizumab, interferon, cyclophotocoagulation, trabeculectomy, iris photocoagulation, ranibizumab, and mitomycin had advantages in terms of improving treatment success rate in NVG patients. However, the application of retinal photocoagulation and vitrectomy reduced patient treatment success rate.

CONCLUSION

The regimen including mitomycin, interferon, and trabeculectomy was the most likely to improve the treatment success rate in NVG patients. The application of glaucoma valve and bevacizumab were more beneficial for improving patient treatment success rate as a surgery and as an agent, respectively.

Changing epidemiology of neovascular glaucoma from 2002 to 2012 at King Khaled Eye Specialist Hospital, Saudi Arabia

PURPOSE

The aim is to present the incidence and determinants of neovascular glaucoma (NVG) in Saudi Arabia.

METHODS

A retrospective review of NVG cases (2002-2012) was included to estimate the incidence. The determinants included gender, age, comorbidities, lens status, type of NVG, and visual acuity on presentation. The impact of antiangiogenic therapy on NVG incidence was studied.

RESULTS

We studied 597 eyes with NVG. The incidence was 6.6/10,000. It declined from 13/10,000 in 2008-0.1/10,000 in 2012 (P < 0.001). The decline in 2008 coincided with the introduction of intravitreal injection bevacizumab in Saudi Arabia. Males had a significantly higher NVG risk (odds ratio [OR] = 2.2). Diabetes and hypertension were associated with NVG in 88% and 42.7% of cases, respectively. In 377 (72%) diabetic patients, the glycemic control was poor (HbA1C >7%). Visual acuity was 20/20-20/40 in 14 (2%), 20/50-20/200 in 79 (13%), 20/200-20/400 in 456 (76%), and <20/400 in 45 (7%) eyes. Intraocular pressure was higher than 30 mmHg in 438 (73%) eyes. The cup-to-disc (CD) ratio was >0.8 in 86 (14%) eyes. During the early period (2002-2007) and later period (2008-2012), CD ratio (χ2 = 4, P = 0.09) and anterior chamber angle (P = 0.8) were not different. The presence of NVG in contralateral eye (OR = 0.8, P = 0.3) in both periods was similar.

CONCLUSIONS

NVG was associated with diabetes in a very large proportion of patients. It was significantly associated with males, and with poor glycemic control and poor vision at presentation. The incidence of NVG declined after the introduction of intravitreal bevacizumab.

Efficacy and safety of intravitreal ranibizumab with panretinal photocoagulation followed by trabeculectomy compared with Ahmed glaucoma valve implantation in neovascular glaucoma

AIM

To evaluate the efficacy and safety of intravitreal ranibizumab (IVR) with panretinal photocoagulation (PRP) followed by trabeculectomy compared with Ahmed glaucoma valve (AGV) implantation in neovascular glaucoma (NVG).

METHODS

This was a retrospective comparative study. We reviewed the cases of a total of 45 eyes from 45 NVG patients among which 23 eyes underwent AGV implantation and the other 22 underwent trabeculectomy. The causes of neovascular glaucoma included: diabetic retinopathy (25 eyes), and retinal vein occlusion (20 eyes). All patients received preoperative IVR combined with postoperative PRP. The mean best-corrected visual acuities (BCVA) were converted to the logarithms of the minimum angle of resolution (logMAR) for the statisitical analyses. Intraocular pressure (IOP), the logMAR BCVA and surgical complications were evaluated before and after surgery. The follow-up period was 12mo.

RESULTS

A total of 39 cases showed complete regression of iris neovascularization at 7d after injection, and 6 cases showed a small amount of residual iris neovascularization. The success rates were 81.8% and 82.6% at 12mo after trabeculectomy and AGV implantation, respectively. In the trabeculectomy group, the logMAR BCVA improved at the last follow-up in 14 eyes, remained stable in 6 eyes and decreased in 2 eyes. In 4 cases, slight hyphemas developed after trabeculectomy. A shallow anterior chamber developed in 2 cases and 2 vitreous hemorrhages. In the AGV group, the logMAR BCVA improved in 14 eyes, remained stable in 5 eyes and decreased in 4 eyes. Slight hyphemas developed in 3 cases, and a shallow anterior chamber in 3 cases. The mean postoperative IOP was significantly lower in both groups after surgery (F=545.468, P<0.05), and the mean postoperative logMAR BCVA was also significantly improved (F=10.964, P<0.05) with no significant difference between two groups.

CONCLUSION

It is safe and effective to treat NVG with this combined procedure, and we found similar results after IVR+AGV implantation+PRP and IVR+trabeculectomy+PRP in eyes with NVG.

Current Perspectives on the Use of Anti-VEGF Drugs as Adjuvant Therapy in Glaucoma

The approval of one of the first anti-vascular endothelial growth factor (VEGF) agents for the treatment of neovascular age-related macular degeneration one decade ago marked the beginning of a new era in the management of several sight-threatening retinal diseases. Since then, emerging evidence has demonstrated the utility of these therapies for the treatment of other ocular conditions characterized by elevated VEGF levels. In this article we review current perspectives on the use of anti-VEGF drugs as adjuvant therapy in the management of neovascular glaucoma (NVG). The use of anti-VEGFs for modifying wound healing in glaucoma filtration surgery (GFS) is also reviewed. Selected studies investigating the use of anti-VEGF agents or antimetabolites in GFS or the management of NVG have demonstrated that these agents can improve surgical outcomes. However, anti-VEGF agents have yet to demonstrate specific advantages over the more established agents commonly used today. Further studies are needed to evaluate the duration of action, dosing intervals, and toxicity profile of these treatments.

Neovascular glaucoma: a review

Neovascular glaucoma (NVG) is a secondary glaucoma generally associated with poor visual prognosis. The development of new vessels over the iris and the iridocorneal angle can obstruct aqueous humor outflow and lead to increased intraocular pressure. The underlying pathogenesis in most cases is posterior segment ischemia, which is most commonly secondary to proliferative diabetic retinopathy or central vein retinal occlusion. The neovascularization process in the eye is driven by the events that alter the homeostatic balance between pro-angiogenic factors, such as the vascular endothelial growth factor and anti-angiogenic factors, such as the pigment-epithelium-derived factor. Early diagnosis of this condition through slit lamp examination of the iris, iridocorneal angle and retina can help to avoid the development of goniosynechia and obstruction of aqueous humor outflow, with consequent intraocular pressure elevation. Historically, NVG treatment was focused on reducing the posterior segment ischemic process that caused the formation of new vessels, through panretinal photocoagulation. Recently, several studies have investigated the application of intravitreal anti-VEGF therapies in NVG. If clinical treatment with the use of hypotensive topical drops is not sufficient, laser and/or surgical procedures are required for intraocular pressure control.

The era of anti-vascular endothelial growth factor (VEGF) drugs in ophthalmology, VEGF and anti-VEGF therapy

Angiogenesis is a clue process for tissue development and function, both in normal and pathological conditions. This process is regulated by multiple molecular systems. One of the most potent is vascular endothelial growth factor (VEGF) and its receptor (VEGFR) system. Members of this family are involved in new vessel formation in embryogenesis and maturation, as well as in reparative or pathological reactions in later stages. They play a substantial role in regeneration, inflammation, wound healing, as well as in cancer pathology. Nowadays it is possible to modulate VEGF-VEGFR interactions in many pathological conditions using anti-VEGF therapy. This therapy has already achieved a grounded position in the management of rheumatological disorders, tumour progression, and metastasis. Such drugs as bevacizumab, ranibizumab, aflibercept, and pegaptanib have also proven to be very effective in the treatment of several ocular diseases, such as age-related macular degeneration (AMD), macular oedema, or proliferative retinopathies and iris neovascularisation. The indications for the application of this therapy in ophthalmology are becoming wider and wider. It may also be used for corneal pathologies and in anti-glaucoma procedures.

Anti-VEGF treatment is the key strategy for neovascular glaucoma management in the short term

Background

To present a comprehensive approach for the management of patients with neovascular glaucoma (NVG) aiming to preserve visual function and complement pan-retinal photocoagulation (PRP) by anti-vascular endothelial growth factor (anti-VEGF) treatment and anti-glaucoma surgery.

Methods

This study includes a prospective, interventional case series. A process flow chart for NVG management was designed. Totally 50 patients (51 eyes) with NVG were included. Of these, 43 patients (44 eyes) completed the treatment process. Patients were divided into central retinal vein occlusion (CRVO) and proliferative diabetic retinopathy (PDR) groups according to their original diagnosis. Intraocular pressure (IOP), visual function, and the status of iris and angle neovascularization were recorded before and after treatment.

Results

Patients were followed up for 6–30 months (mean 12.2 months). The IOP of all 44 patients was effectively controlled and was significantly less after treatment (16.68 ± 4.69 mmHg) than before treatment (42.59 ± 9.44 mmHg, P < 0.05). Thirty-nine eyes displayed controlled IOP (≤21 mmHg) after treatment. Visual acuity improved, to some extent, in 32 eyes (72.9 %), and 12 eyes (27.3 %) had a visual acuity better than 0.1. There was no significant difference in IOP between the PDR and CRVO groups at the end of follow-up (P = 0.8657), but the visual acuity in the PDR group was much better than that in the CRVO group (P = 0.0079).

Conclusions

A comprehensive therapy for NVG can effectively control IOP and preserve visual function in patients by anti-VEGF injection and anti-glaucoma surgery.

Prognostic Factor Analysis of Intraocular Pressure with Neovascular Glaucoma

Purpose. To perform multivariate analysis for identifying independent predictors of elevated intraocular pressure (IOP) with neovascular glaucoma (NVG), including antivascular endothelial growth factor (VEGF) intravitreal injections. Methods. We retrospectively reviewed 142 NVG patients (181 eyes) with ischemic retinal diseases [proliferative diabetic retinopathy (PDR) in 134 eyes, retinal vein occlusion (RVO) in 29, and ocular ischemic syndrome in 18]. We analyzed age, gender, initial/final LogMAR VA, initial/final IOP, extent of iris and/or angle neovascularization, treatments, preexisting complications, concurrent medications, and follow-up duration. Results. The mean follow-up duration was 23.8 ± 18.8 months. At the final follow-up, 125 (72.3%) eyes had IOP ≤ 21 mmHg. NVG patients with RVO had a higher degree of angle closure and higher IOP. NVG with PDR had better IOP and LogMAR VA. Angle closure had the greatest impact on final IOP. Greater than 90% of patients treated with trabeculectomy with mitomycin C (LEC) had persistent declines in IOP (≤21 mmHg). Stand-alone and combination anti-VEGF therapies were not associated with improved long-term prognosis of IOP. Conclusions. Angle closure was found to have the greatest effect on NVG-IOP prognosis. When target IOP values are not obtained after adequate PRP with or without anti-VEGF, early LEC may improve the prognosis of IOP.

Intravitreal ranibizumab injection combined trabeculectomy versus Ahmed valve surgery in the treatment of neovascular glaucoma: assessment of efficacy and complications

BACKGROUND

Researches have shown anti-vascular endothelial growth factor (VEGF) agent is effective in treating neovascular eye diseases. The purpose of this study is to evaluate the efficacy and safety of intravitreal ranibizumab (IVR) injection combined trabeculectomy in the treatment of neovascular glaucoma (NVG), and compared it with Ahmed valve surgery.

METHODS

Thirty-six NVG patients (37 eyes) from the First Affiliated Hospital of Zhejiang medical college, between January 1, 2014 and January 31, 2015, were included in this prospective, interventional clinical study. Eighteen NVG eyes were given IVR injection one week before trabeculectomy. Ahmed valve implantation surgery was performed in nineteen eyes. Ocular pain, best corrected visual acuity (BCVA), intraocular pressure (IOP) and surgical complications were evaluated before and after the surgery.

RESULTS

IOP was significantly decreased following IVR injection combined trabeculectomy treatment (baseline 57.1 ± 8.9 mmHg; week 1, 15.2 ± 4.3 mmHg p = 0.000; month 1, 16.9 ± 2.1 mmHg p = 0.000; month 3, 20.3 ± 7.7 mmHg p = 0.000; month 6, 19.7 ± 7.3 mmHg p = 0.000). There was a significant, though modest, BCVA improvement in sighted eyes of IVR group (baseline 2.42 ± 0.68, W1 1.80 ± 0.91, P = 0.013; M1 1.77 ± 0.93, p = 0.011). IVR injection combined trabeculectomy had less postoperative complications and lower failure ratio than Ahmed surgery (IVR 5.6 %, Ahmed 31.6 %).

CONCLUSIONS

The study revealed that IVR injection combined trabeculectomy was an effective and safe treatment for NVG. Compared with Ahmed surgery, IVR injection combined trabeculectomy had less complications and higher success ratio. (Chinese Clinical Registry, TRN ChiCTR-OPN-16008147, 3/24/2016, retrospectively registered).

Intravitreal Ranibizumab Injection as an Adjuvant in the Treatment of Neovascular Glaucoma Accompanied by Vitreous Hemorrhage after Diabetic Vitrectomy

Purpose. To determine the efficacy of intravitreal ranibizumab injection as adjuvant therapy in the treatment of neovascular glaucoma (NVG) accompanied by postvitrectomy diabetic vitreous hemorrhage (PDVH). Methods. Eighteen NVG patients (18 eyes) accompanied by PDVH were enrolled in this prospective, monocenter, 12-month, interventional case series. The consecutive 18 patients with an IOP ≥ 25 mmHg despite being treated with the maximum medical therapy were treated with intravitreal ranibizumab injections. Vitreous surgery or/with Ahmed valve implantation were indicated if no clinical improvement in vitreous haemorrhage and uncontrolled IOP was shown. Results. Ten patients got clear vitreous and controlled IOP only with 2.7 ± 1.8 injections of ranibizumab without additional surgery. Vitrectomy or/with Ahmed valve implantation was administered in the other 8 eyes due to uncontrolled VH and IOP. At follow-up month 12, all the 18 eyes gained clear vitreous. At month 12 BCVA improved significantly compared to baseline. The baseline and follow-up at month 12 IOP/medication usage were 36.7 ± 8.1 mmHg on 3.4 ± 0.7 medications and 16.2 ± 4.9 mmHg on 0.67 ± 0.77 medications, respectively. Conclusions. The findings suggest that intravitreal ranibizumab injection as adjuvant therapy for treatment of NVG accompanied by PDVH may be safe and potentially effective. This clinical trial is registered with NCT02647515.

MicroRNA-26a overexpression protects RGC-5 cells against H2O2-induced apoptosis

BACKGROUND

We intended to examine the functional role of microRNA 26 (miR-26a) in regulating H2O2-induced cytotoxicity and apoptosis in RGC-5 cells in vitro.

METHOD

Various concentrations of H2O2 (0-1000 μM) were added in RGC-5 culture. Cell cytotoxicity was monitored by viability assay and gene expression level of miR-26a examined by qRT-PCR. MicroRNA-26a mimic was then applied in the RGC-5 culture to examine its effect on upregulating endogenous miR-26a and rescuing H2O2-induced cytotoxicity. TUNEL immunostaining assay was used to further assess the protective effect of upregulating miR-26a on H2O2-induced apoptosis in RGC-5 cells. Direct targeting of miR-26a on Phosphatase and tensin homolog (PTEN) signaling pathway was assessed by luciferase assay and western blotting. PTEN was then ectopically over-expressed in RGC-5. And its effects on miR-26a mediated apoptosis protection in RGC-5 were investigated by western blot and TUNEL assay.

RESULTS

H2O2 induced cytotoxicity and down-regulated miR-26a in dose-dependent manner in RGC-5 cells. MiR-26a-mimic upregulated endogenous miR-26a gene levels, and then reduced H2O2-induced cytotoxicity, as well as H2O2-induced apoptosis in RGC-5 cells. PTEN was directly targeted by miR-26a. PTEN protein was upregulated, and phosphorylated AKT protein down-regulated while miR-26a was upregulated to reduce H2O2-induced apoptosis. Finally, overexpressing PTEN reversed the protective effect of miR-26a upregulation on RGC-5 apoptosis.

CONCLUSION

Upregulating miR-26a protects RGC-5 cell against cytotoxicity and apoptosis, probably through down-regulation of PTEN.

Intravitreal bevacizumab and Ahmed glaucoma valve implantation in patients with neovascular glaucoma

AIM

To explore the efficacy of preoperative intravitreal bevacizumab (IVB) injection combined with Ahmed glaucoma valve (AGV) implantation in the treatment of neovascular glaucoma (NVG).

METHODS

This retrospective study included 35 eyes from 35 patients who underwent preoperative IVB and AGV implantation for treatment of NVG. Findings such as intraocular pressure (IOP) number of anti-glaucoma medications, visual acuity (VA), surgical success rates, and complications were recorded.

RESULTS

After AGV implantation, IOP was 18.2±4.0 mm Hg, 15.5±3.3 mm Hg and 9.8±2.6 mm Hg at 6, 12 and 36mo, significantly decreased compared with pre-IOP (P<0.01). The number of anti-glaucoma medications was 0.9±0.5, 0.8±0.9 and 0.8±0.6 at 6, 12 and 36mo, significantly decreased compared to pre-treatment (P<0.01). At last visit, there were 19 eyes with stable VA, 4 with VA improvement, 12 with diminished VA and 3 with complete loss light perception. There were 7 cases that failed during 3-year fellow up period. Cumulative probabilities of valve survival by Kaplan-Meier analysis were 82.9%, 74.1% and 71.0% at 12, 24 and 36mo, respectively. Cox stepwise regression analysis found that the survival time was significant associated with the pre-visual acuity <2/400 (P<0.05). Post-operative complications occurred in 8 eyes, of which hyphema presented in 2 eyes, choroidal effusion in 2 eyes.

CONCLUSION

The procedure of preoperative IVB and AGV implantation should be one of treatments for NVG because of its safety and effectiveness.

The link between intravitreal antivascular endothelial growth factor injections and glaucoma

PURPOSE OF REVIEW

To summarize the reports of both transient and sustained elevation in intraocular pressure (IOP) associated with intravitreal injections of antivascular endothelial growth factor (anti-VEGF) agents and to review the possible mechanisms for these findings.

RECENT FINDINGS

Transient elevation in IOP is common after intravitreal injection of anti-VEGF agents. Sustained IOP elevation is less commonly seen but can require medical and/or surgical intervention. The mechanism for sustained IOP elevation is not well understood but has been attributed to trabecular meshwork injury from repeated injections, a potential toxic or inflammatory reaction after exposure to the biologic agents and/or vehicle, or mechanical blockade of the trabecular meshwork by protein aggregates or contaminant particles associated with packaging and injection techniques, among other potential causes.

SUMMARY

Intravitreal anti-VEGF injections are commonly used to treat neovascular diseases of the eye. Although they have a favorable side-effect profile, their use can be associated with both transient and sustained elevation in IOP. Further research is necessary to determine the cause of these findings.