Construction and validation of a neovascular glaucoma nomogram in patients with diabetic retinopathy after pars plana vitrectomy

BACKGROUND

Neovascular glaucoma (NVG) is likely to occur after pars plana vitrectomy (PPV) for diabetic retinopathy (DR) in some patients, thus reducing the expected benefit. Understanding the risk factors for NVG occurrence and building effective risk prediction models are currently required for clinical research.

AIM

To develop a visual risk profile model to explore factors influencing DR after surgery.

METHODS

We retrospectively selected 151 patients with DR undergoing PPV. The patients were divided into the NVG (NVG occurrence) and No-NVG (No NVG occurrence) groups according to the occurrence of NVG within 6 months after surgery. Independent risk factors for postoperative NVG were screened by logistic regression. A nomogram prediction model was established using R software, and the model's prediction accuracy was verified internally and externally, involving the receiver operator characteristic curve and correction curve.

RESULTS

After importing the data into a logistic regression model, we concluded that a posterior capsular defect, preoperative vascular endothelial growth factor ≥ 302.90 pg/mL, glycosylated hemoglobin ≥ 9.05%, aqueous fluid interleukin 6 (IL-6) ≥ 53.27 pg/mL, and aqueous fluid IL-10 ≥ 9.11 pg/mL were independent risk factors for postoperative NVG in patients with DR (P < 0.05). A nomogram model was established based on the aforementioned independent risk factors, and a computer simulation repeated sampling method was used to internally and externally verify the nomogram model. The area under the curve (AUC), sensitivity, and specificity of the model were 0.962 [95% confidence interval (95%CI): 0.932-0.991], 91.5%, and 82.3%, respectively. The AUC, sensitivity, and specificity of the external validation were 0.878 (95%CI: 0.746-0.982), 66.7%, and 95.7%, respectively.

CONCLUSION

A nomogram constructed based on the risk factors for postoperative NVG in patients with DR has a high prediction accuracy. This study can help formulate relevant preventive and treatment measures.

Cognitive bias evaluation on the choice of treatment in common retinal disorders among retina specialists in 2023

PURPOSE

The study aimed to discern the intent to treat with the therapeutic agents prescribed first or second line in the following eye conditions: neovascular age-related macular Degeneration (nAMD), diabetic macular edema (DME), retinal vein occlusion (RVO), and myopic maculopathy with choroidal neovascularization (MMNV). The study also aimed to distinguish the ophthalmologists' intended treatment for their patients from those that they would prescribe for themselves if they were affected by the above macular conditions.

METHODS

The study utilized an online survey of 243 French ophthalmologists practicing medical retina, with males accounting for 54.3% of the participants. Data was obtained using a questionnaire that focused on the ophthalmologists' experience with various agents as well as their first and second line choices for nAMD, DME, RVO, and MMNV.

RESULTS

The vast majority of French ophthalmologists (99%) had experience with the most widely used anti-vascular endothelial growth factors (anti-VEGFs); ranibizumab, bevacizumab, and aflibercept. Fewer than 8% reported experience with anti-VEGF drug reservoirs, biosimilars, or faricimab. The study findings also showed ranibizumab and aflibercept as the commonly prescribed first line choices for the above-mentioned ocular conditions. For the second line choice, the study showed that aflibercept and dexamethasone intravitreal implants were the most common across the four retinal conditions studied. The only difference in intent to treat for "patients" versus "yourself" was for biosimilars (0% to 0.8%, P=0.001).

CONCLUSION

The findings regarding the first and second line choices for the mentioned ocular disorders were found to agree with the findings of published literature currently used in practice, with a tendency to prefer ranibizumab as first line therapy for neovascular disorders and aflibercept as first line therapy for macular edema. In addition, there were no differences between choices for first and second line therapy for patients vs. ophthalmologists.

Short-term outcomes of treatment switch to faricimab in patients with aflibercept-resistant neovascular age-related macular degeneration

PURPOSE

To report short-term outcomes of treatment switch to faricimab in real-world patients with aflibercept-resistant neovascular age-related macular degeneration (AMD).

METHODS

Single-center, retrospective cohort study with chart-review using electronic injection database, electronic medical records, and optical coherence tomography (OCT) data from May to September 2023.

RESULTS

A total of 50 eyes of 46 patients were analyzed. Faricimab treatment led to absence of fluid in 32% of the eyes and a reduction of fluid in 84% of the eyes. There was a statistically significant decrease in central retinal thickness (CRT) and pigment epithelial detachment (PED) height in those that responded to the switch (median difference: - 31 μm, IQR: 55, p < 0.0001 and median difference: - 21 μm, IQR: 36, p < 0.0001, respectively) and a statistically significant increase in CRT (median difference: + 19 μm, IQR: 20, p = 0.0143) and no change in PED height (median difference: + 22 μm, IQR: 64, p = 0.1508) in those that did not. Best-corrected visual acuity (BCVA) showed marginal decrease with low statistical significance. No ocular or systemic safety events were observed.

CONCLUSIONS

Our findings suggest that switching to faricimab is generally safe and effective in patients with neovascular AMD who are otherwise difficult to treat and have residual fluid despite frequent injections with aflibercept. We observed a high rate of morphological response to the treatment switch, improvement of anatomical parameters with about one-third of patients having dry macula following a single injection, and a marginal change in BCVA. Sustainability of these results requires further investigation.

STUDY REGISTRATION

ClinicalTrials.gov registration number: NCT06124677. Date of registration: 09/11/2023, retrospectively registered.

Correlations between subfoveal choroidal thickness, macular thickness, and visual outcome in neovascular age-related macular degeneration using swept source OCT: insights from intravitreal aflibercept treatment

BACKGROUND

Age-related macular degeneration (AMD) is a leading cause of visual impairment among individuals aged 50 and above, often resulting in irreversible vision loss (1). Currently, antiangiogenic therapy is the primary treatment approach for neovascular AMD (2). The choroid has gained significant attention in recent years due to its involvement in various ocular pathologies (7). The objective of this study was to evaluate visual acuity and correlate pre-treatment variables, such as foveal thickness and choroidal thickness, with post-treatment outcomes.

MATERIALS AND METHODS

This study was designed as a prospective interventional study to investigate the changes in choroidal and macular thickness in patients with neovascular AMD who received intravitreal aflibercept injections. The study utilized medical records and employed Swept Source Optical Coherence Tomography (OCT-SS) for evaluation. The data was collected from patients treated in Presidente Prudente, Brazil, during a three-month load dose period.

RESULTS

The best-corrected mean visual acuity significantly improved from 1.0 logarithm of the minimum resolution angle (logMAR) units to 0.55 logMAR after treatment with aflibercept (p < 0.001). Patients undergoing treatment exhibited a significant decrease in average macular thickness from 323 μm to 232 μm (p = 0.001), as well as a reduction in choroidal thickness from 206 μm to 172 μm (p = 0.031), while maintaining intraocular pressure within the normal range (p = 0.719) without significant variation. Statistically significant associations were found between the difference in pre- and post-treatment choroidal thickness and the pretreatment values of macular thickness (p = 0.005) and choroidal thickness (p = 0.013). There was also a statistically significant correlation between the difference in pre- and post-treatment macular thickness and the pretreatment macular thickness value (p < 0.001).

CONCLUSION

In this study, aflibercept exhibited remarkable effectiveness in reducing macular and choroidal thickness, as evaluated using OCT-SS, and significantly improved visual acuity in patients with neovascular AMD. The assessment of both choroidal and macular changes, as well as their correlations, can provide valuable insights for clinicians, enabling them to make well-informed therapeutic decisions and effectively monitor treatment outcomes. Notably, this study contributes to the existing body of literature as the first to establish a correlation between pretreatment foveal thickness, variation in choroidal thickness, and post-treatment choroidal thickness.

Two-year outcomes of patients presenting to Sydney Eye Hospital with neovascular glaucoma

BACKGROUND

Neovascular glaucoma (NVG) is a sight-threatening condition that is often refractory to treatment. Current management principles are yet to be standardized due to lack of evidence. We studied the interventions used to treat NVG at Sydney Eye Hospital (SEH) and the two-year surgical outcomes.

METHODS

We performed a retrospective audit of 67 eyes of 58 patients with NVG from January 1, 2013, to December 31, 2018. Intraocular pressure (IOP), best-corrected visual acuity (BCVA), number of medications, repeat surgery, recurrent neovascularization, loss of light perception and pain were studied.

RESULTS

The average age of the cohort was 59.67 years (SD 14.22). The most common etiologies were proliferative diabetic retinopathy (35 eyes; 52.2%), central retinal vein occlusion (18 eyes; 26.9%) and ocular ischemic syndrome (7 eyes; 10.4%). 70.1% of eyes (47) received vascular endothelial growth factor injections (VEGFI), 41.8% (28 eyes) received pan-retinal photocoagulation (PRP) and 37.3% (25 eyes) received both prior to or within the first week of presentation to SEH. The most common initial surgical interventions were trans-scleral cyclophotocoagulation (TSCPC) (36 eyes; 53.7%) and Baerveldt tube insertion (18 eyes; 26.9%). 62.7% of eyes (42 eyes) failed (IOP > 21 or < 6 mmHg for two consecutive reviews, further IOP-lowering surgery or loss of light perception) during follow-up. Initial TSCPC failed in 75.0% (27/36 eyes) compared with 44.4% (8/18 eyes) after Baerveldt tube insertion.

CONCLUSION

Our study reinforces the refractory nature of NVG, often despite intensive treatment and surgery. Improvements in patient outcomes may be achieved with earlier consideration of VEGFI and PRP. This study identifies the limitations of surgical interventions for NVG and highlights the need for a standardized management approach.

Polymer based sustained drug delivery to the ocular posterior segment: barriers and future opportunities for the treatment of neovascular pathologies

There is an increasing momentum in research and pharmaceutical industry communities to design sustained, non-invasive delivery systems to treat chronic neovascular ocular diseases that affect the posterior segment of the eye including age-related macular degeneration and diabetic retinopathy. Current treatments include VEGF blockers, which have revolutionized the standard of care for patients, but their maximum therapeutic benefit is hampered by the need for recurrent and invasive administration procedures. Currently approved delivery systems intended to address these limitations exploit polymer technology to regulate drug release in a sustained manner. Here, we critically review sustained drug delivery approaches for the treatment of chronic neovascular diseases affecting the ocular posterior segment, with a special emphasis on novel and polymeric technologies spanning the spectrum of preclinical and clinical investigation, and those approved for treatment. The mechanism by which each formulation imparts sustained release, the impact of formulation characteristics on release and foreign body reaction, and special considerations related to the translation of these systems are discussed.

The influence of etiology on surgical outcomes in neovascular glaucoma

Background

The authors sought to evaluate visual outcomes in patients with varying etiologies of neovascular glaucoma (NVG), who were treated with glaucoma drainage devices (GDD).

Methods

This was a retrospective case series of patients at a large academic teaching institution who had surgical intervention for neovascular glaucoma between September 2011 and May 2019. Eyes were included if there was documented neovascularization of the iris/angle with an intraocular pressure (IOP) > 21 mmHg at presentation. Eyes must also have been treated with surgical intervention that included a GDD. Primary outcome measure was visual acuity at the 1-year post-operative visit. Secondary outcome measure was qualified success after surgery defined by: pressure criteria (5 mmHg < IOP ≤ 21 mmHg), no re-operation for elevated IOP, and no loss of LP vision.

Results

One hundred twenty eyes met inclusion criteria. 61.7% had an etiology of proliferative diabetic retinopathy (PDR), 23.3% had retinal vein occlusions (RVO), and the remaining 15.0% suffered from other etiologies. Of patients treated with GDD, eyes with PDR had better vision compared to eyes with RVO at final evaluation (p = 0.041). There was a statistically significant difference (p = 0.027) in the mean number of glaucoma medications with Ahmed eyes (n = 70) requiring 1.9 medications and Baerveldt eyes (n = 46) requiring 1.3 medications at final evaluation.

Conclusions

In our study, many patients with NVG achieved meaningful vision, as defined by World Health Organization (WHO) guidelines, and IOP control after GDD. Outcomes differed between patients with PDR and RVO in favor of the PDR group. Different GDD devices had similar performance profiles for VA and IOP outcomes. Direct prospective comparison of Baerveldt, Ahmed, and cyclophotocoagulation represents the next phase of discovery.

PRN Treatment of Neovascular AMD with Cycles of Three Monthly Injections

Purpose

To report the one and two year outcome of cycles of three, monthly anti-VEGF injections given upon reactivation of the disease in eyes with neovascular age-related macular degeneration (nAMD).

Methods

Retrospective study of naïve nAMD cases with more than one year of follow-up, treated with a protocol of cycles of three monthly injections of anti-VEGF drugs upon reactivation. Visual acuity (VA) and central macular thickness (CMT) are the main outcome measures.

Results

Twenty-six patients with a mean age of 78.15 ± 9.29 years (57.7% female) were included. The mean follow-up was 30.89 ± 6.95 months. Treatment started with bevacizumab in all patients but in six patients was switched to aflibercept due to inadequate response to intravitreal bevacizumab injection. The mean VA at baseline and at 12 and 24 months was 53.87 ± 21.84, 60.54 ± 21.13, and 53.68 ± 27.16 ETDRS letters, respectively. Patients gained a mean of 6.67± 13.7 (p = 0.013, 95% CI= 0.60 to 12.65) and 0.77±15.21 (p = 0.4, 95% CI: –5.65 to 7.2) letters at 12 and 24 months. CMT at baseline, 12, and 24 months was 403.55 ± 147.59, 323.95 ± 79.58, and 298.59 ± 77.161 µm, respectively. The number of injections in the first and second years were 7.65 ± 2.64 and 5.52 ± 3.01, respectively. Three eyes (12.5%) lost >15 letters at 24 months.

Conclusion

This protocol can stabilize or improve vision in 87.5% of nAMD patients and can reduce the number of visits.

Safety and efficacy of Razumab™ (world's first biosimilar ranibizumab) in wet age-related macular degeneration: a post-marketing, prospective ASSET study

Background

Razumab™ (world’s first biosimilar ranibizumab) is approved for several macular disorders including wet age-related macular degeneration (AMD). We evaluated the safety and efficacy of biosimilar ranibizumab in wet AMD.

Methods

This prospective, multicentre, rAnibizumab bioSimilar Safety Efficacy postmarkeTing (ASSET) study enrolled patients aged ≥ 50 years with wet AMD having best-corrected visual acuity (BCVA) between 20/40 and 20/320. The patients received intravitreal biosimilar ranibizumab 0.5 mg every 4 weeks for 24 weeks. Safety endpoints included the incidence of adverse events (AEs), serious AEs (SAEs), and immunoreactivity after 6 months. The efficacy endpoints were the proportion of patients who lose fewer than 15 letters, increase in BCVA, change in central retinal thickness (CRT), and change in Visual Function Questionnaire-25 (VFQ-25) score, from baseline to 24 weeks.

Results

Of the 126 enrolled patients, majority (95.24%) of the patients received all 6 doses of biosimilar ranibizumab (total 3 mg). Nineteen AEs were reported (n = 16; 12.7%); majority (78.9%) were mild. There were no serious AEs reported, except one AE of death which was unrelated to the study drug. None of the patients discontinued the study due to an AE. The most common ocular AE was increase in intraocular pressure (4 events) and non-ocular AE was pyrexia (5 events). A total of 7.9% (10/126) patients prior to dosing and 7.1% (9/126) patients post-treatment were positive for anti-ranibizumab antibodies. No AEs suggestive of immunogenicity were noted. At 24-weeks, 97.60% patients in the intent-to-treat (ITT) population (N = 125) and 97.41% patients in the per-protocol (PP) population (N = 116) lost < 15 letters from baseline visual acuity. In the ITT and PP populations, 31.20% and 32.76% patients, respectively, showed improved visual acuity by ≥ 15 letters. Significant improvements in BCVA (mean difference: 8.8, 9.2, p < 0.001 for ITT, PP) and VFQ-25 (8.5, 9.2, p < 0.001 for ITT, PP) were seen; CRT reduced significantly (125 µm, 119.3 µm, p < 0.001 for ITT, PP).

Conclusion

Razumab™ (world’s first biosimilar ranibizumab) was well-tolerated without new safety concerns and significantly improved visual acuity in wet AMD patients.

Trial registration CTRI/2016/03/006739. Registered 18 March 2016—Prospectively registered, http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=13141&EncHid=&userName=2016/03/006739

Supplementary Information

The online version contains supplementary material available at 10.1186/s40942-021-00293-w.

PERSEUS 24-month analysis: a prospective non-interventional study to assess the effectiveness of intravitreal aflibercept in routine clinical practice in Germany in patients with neovascular age-related macular degeneration

PURPOSE

To evaluate the real-world effectiveness of intravitreal aflibercept injections in Germany in patients with neovascular age-related macular degeneration over 24 months.

METHODS

PERSEUS was a prospective, non-interventional cohort study. The primary endpoint was the mean change in visual acuity (VA) from baseline. Secondary endpoints included the proportion of patients with a VA gain or loss of ≥ 15 letters and the frequency of injections and examinations. Patients with regular (bimonthly after 3 monthly injections during year 1 and ≥ 4 injections in year 2) and irregular (any other) treatment were analyzed. The last observation carried forward (LOCF) and the observed cases (OC) approach was applied for primary endpoint analysis to account for missing data.

RESULTS

803 patients were considered for effectivity analysis. At month 24, only 38% of the patients were still under observation. The LOCF population included 727, the OC population 279 patients. Treatment-naïve patients improved by 6.3 (LOCF)/8.1 (OC) letters with regular treatment over 24 months but only by 3.3 (LOCF)/3.1 (OC) letters with irregular treatment. The proportion of treatment-naïve patients achieving a VA improvement of ≥ 15 letters was similar between regularly and irregularly treated cohorts. However, considerably more patients in the irregular cohorts experienced a VA worsening of ≥ 15 letters than in the regular cohorts (LOCF: 18.7% vs. 7.4%).

CONCLUSIONS

Regular IVT-AFL treatment resulted in better VA outcomes than irregular treatment at month 24. However, only a minority of patients received regular treatment over a 2-year period.

Age-Related Macular Degeneration: Epidemiology and Clinical Aspects

Age-related macular degeneration (AMD) is a degenerative disease of the human retina affecting individuals over the age of 55 years. This heterogeneous condition arises from a complex interplay between age, genetics, and environmental factors including smoking and diet. It is the leading cause of blindness in industrialized countries. Worldwide, the number of people with AMD is predicted to increase from 196 million in 2020 to 288 million by 2040. By this time, Asia is predicted to have the largest number of people with the disease. Distinct patterns of AMD prevalence and phenotype are seen between geographical areas that are not explained fully by disparities in population structures. AMD is classified into early, intermediate, and late stages. The early and intermediate stages, when visual symptoms are typically absent or mild, are characterized by macular deposits (drusen) and pigmentary abnormalities. Through risk prediction calculators, grading these features helps predict the risk of progression to late AMD. Late AMD is divided into neovascular and atrophic forms, though these can coexist. The defining lesions are macular neovascularization and geographic atrophy, respectively. At this stage, visual symptoms are often severe and irreversible, and can comprise profoundly decreased central vision in both eyes. For these reasons, the condition has major implications for individuals and society, as affected individuals may experience substantially decreased quality of life and independence. Recent advances in retinal imaging have led to the recognition of an expanded set of AMD phenotypes, including reticular pseudodrusen, nonexudative macular neovascularization, and subtypes of atrophy. These developments may lead to refinements in current classification systems.

Anti-vascular endothelial growth factor in neovascular age-related macular degeneration - a systematic review of the impact of anti-VEGF on patient outcomes and healthcare systems

Background

Systematically review the evidence describing the impact of anti–vascular endothelial growth factor (anti-VEGF) therapy on neovascular age-related macular degeneration (nAMD) patient outcomes and healthcare resource utilization.

Methods

A systematic literature review was completed using Medline and EMBASE for publications prior to July 2018, and proceedings from major ophthalmology conferences (January 2016 to July 2018). The search strategy combined terms for nAMD with terms for anti-VEGF and study design. The review focused on publications describing the impact of anti-VEGF on blindness, visual impairment, vision-related quality of life (VRQoL), mortality, and costs. The search targeted data collected in epidemiological or observational studies to reflect real-world outcomes but also considered modeling-based approaches.

Results

The use of anti-VEGF in clinical practice was associated with significant reduction in the incidence of blindness by nAMD. Population-based analyses reported reduction in incidence among the general population of 47% (9.1 cases/100,000 in 2006 to 4.8 cases/100,000 in 2011). Among patients aged ≥50 years, a reduction of 50% was observed (52.2 cases/100,000 in 2000 to 25.7 cases/100,000 in 2010). In some cases, the odds of decreased vision (defined as decline from normal to moderate, moderate to severe, or severe to blindness) fell by 41% following introduction of anti-VEGF. Patients’ VRQoL improved with treatment, with patients reporting a positive impact shortly after treatment was initiated. Change on National Eye Institute 25-Item Visual Function Questionnaire score from baseline to month 12 ranged from 0.7 to 4.4. Although nAMD patients report signs of depression and anxiety, the evidence suggests that there is no association between the use of anti-VEGF and the prevalence or diagnosis of depression. The introduction of anti-VEGF led to increased overall treatment costs due to replacement of existing less frequently administered treatments (e.g. photodynamic therapy) and increased number of patients treated (prior to anti-VEGF, only ~ 20% of patients were eligible for treatment).

Conclusions

The introduction of anti-VEGF agents has been associated with a positive impact on patient-relevant outcomes, including a significant reduction in incidence of blindness and visual impairment by nAMD. Anti-VEGF agents replaced less-effective treatments, improving patient outcomes and broadening the patient population eligible for treatment.

Severe vision loss secondary to retinal arteriolar occlusions after multiple intravitreal brolucizumab administrations

Purpose

To describe a case of unilateral retinal arteriolar occlusion following multiple intravitreal brolucizumab injections for neovascular age-related macular degeneration (nAMD).

Observations

A 92-year-old Caucasian woman presented with blurry vision in her left eye (OS) after receiving the third dose of intravitreal brolucizumab. At the time of presentation, visual acuity (VA) was 20/40 in her right eye (OD) and had decreased from 20/150 to count finger (CF) at 1-foot OS. On examination, there was no evidence of active inflammation in the anterior chamber OU. Dilated fundus examination showed no vitritis in OD and 1+ vitreous cells OS, flame-shaped hemorrhage at the superior optic disc margin, and retinal whitening surrounding the proximal portion of the supero-temporal branch of the central retinal artery. There were drusen in OS and retinal pigment epithelial (RPE) changes in the maculae of OU. Intra-arteriolar greyish deposits were seen OS. Fluorescein angiography (FA) showed hyper-fluorescence in the maculae corresponding to fibrovascular pigment epithelial detachments (PED) OU. No peri-vascular leakage was noted OU. Delayed filling of multiple arterioles in early and late phases OS was observed on FA. The patient was diagnosed with retinal arteriolar occlusion associated with repeated intravitreal brolucizumab administrations.

Conclusion

Retinal arteriolar occlusion with severe vision loss, possibly secondary to inflammatory responses, can occur after subsequent intravitreal brolucizumab injections, even if no inflammation occurred after initial administrations. Vaso-occlusive disease should be considered as a potential ocular complication, with acute as well as delayed onset, following intravitreal brolucizumab therapy.

Herpes Zoster Ophthalmicus, Central Retinal Artery Occlusion, and Neovascular Glaucoma in an Immunocompetent Individual

Purpose

To report the unusual case of an immunocompetent individual with herpes zoster ophthalmicus who developed central retinal artery occlusion and subsequent neovascular glaucoma.

Case Report

A 40-year-old, immunocompetent patient was diagnosed with herpes zoster ophthalmicus and central retinal artery occlusion on initial presentation. Subsequently, he developed neovascular glaucoma.

Conclusion

There are a few case reports of central retinal artery occlusion developing after varicella zoster virus infection. However, a literature search found no reports of neovascular glaucoma following central retinal artery occlusion secondary to varicella zoster virus infection. The present case report indicates that neovascular glaucoma is a possible complication in such a scenario.

Mini-peptide RPL41 attenuated retinal neovascularization by inducing degradation of ATF4 in oxygen-induced retinopathy mice

Endoplasmic reticulum (ER) stress signaling is activated in retinal degeneration disease. Activating transcription factor 4 (ATF4), an important mediator of the unfolded protein response (UPR), is a key element that maintains cell survival and proliferation in hypoxic conditions. Our previous studies showed that a small ribosomal protein L41 (RPL41) inhibits ATF4 by inducing its phosphorylation and degradation. In the present study, the effects of mini-peptide RPL41 on retinal neovascularization (RNV) in oxygen-induced retinopathy (OIR) mice was investigated. We induced OIR in C57BL/6 mice and obtained retinas from normoxia, OIR, OIR control (treated with PBS), and OIR treated (treated with RPL41) mice. Our results showed that ER stress signaling was activated and ATF4 was overexpressed in the retinas of OIR mice. After intravitreal injection of RPL41, the size of RNV and vaso-obliteration, and the number of preretinal neovascular cell nuclei in the retinas of OIR mice were significantly decreased. Western blot analysis and quantitative real-time polymerase chain reaction (qPCR) showed ATF4 and VEGF expression decreased after intravitreal injection of RPL41. Furthermore, the expression levels of inflammatory genes including TNF-α, IL-1β, and IL-6 were significantly decreased compared with the OIR control mice. In conclusion, RPL41 prevented pathologic neovascularization and exerted anti-inflammatory effects by degrading the important ER stress factor ATF4, thus, RPL41 could be a promising therapeutic agent for the treatment of neovascular eye diseases, especially retinopathy of prematurity (ROP).

Norrin treatment improves ganglion cell survival in an oxygen-induced retinopathy model of retinal ischemia

Treatment of a mouse model of oxygen-induced retinopathy (OIR) with recombinant human Norrin (Norrie Disease Protein, gene: NDP) accelerates regrowth of the microvasculature into central ischemic regions of the neural retina, which are generated after treatment with 75% oxygen. While this reduces the average duration and severity of ischemia overall, we do not know if this accelerated recovery of the microvasculature results in any significant survival of retinal ganglion cells (RGCs). The purpose of this study was to investigate ganglion cell survival with and without the intravitreal injection of Norrin in the murine model of oxygen induced retinopathy (OIR), using two strains of mice: C57BL/6J and Thy1-YFP mice. Intravitreal injections of Norrin or vehicle were done after five days of exposure to 75% oxygen from ages P7 to P12. The C57BL/J mice were followed by Spectral-Domain Optical Coherence Tomography (SD-OCT), and the average nerve fiber layer (NFL) and inner-plexiform layer (IPL) thicknesses were measured at twenty-four locations per retina at P42. Additionally, some C57BL/J retinas were flat mounted and immunostained for the RGC marker, Brn3a, to compare the population density of surviving retinal ganglion cells. Using homozygous Thy1-YFP mice, single intrinsically fluorescent RGCs were imaged in live animals with a Micron-III imaging system at ages P21, 28 and P42. The relative percentage of YFP-fluorescent RGCs with dendritic arbors were compared. At age P42, the NFL was thicker in Norrin-injected OIR eyes, 14.4 μm, compared to Vehicle-injected OIR eyes, 13.3 μm (p = 0.01). In the superior retina, the average thickness of the IPL was greater in Norrin-injected OIR eyes, 37.7 μm, compared to Vehicle-injected OIR eyes, 34.6 μm (p = 0.04). Retinas from Norrin injected OIR mice had significantly more surviving RGCs (p = 0.03) than vehicle-injected mice. Based upon NFL thickness and counts of RGCs, we conclude that Norrin treatment, early in the ischemic phase, increased the relative population density of surviving RGCs in the central retinas of OIR mice.

Clinical Features of Ocular Ischemic Syndrome and Risk Factors for Neovascular Glaucoma

Purpose

We aimed to examine the clinical features and prognosis of ocular ischemic syndrome and to investigate the risk factors for the development of neovascular glaucoma (NVG).

Methods

The medical records from 25 patients (25 eyes) who were diagnosed with ocular ischemic syndrome were retrospectively analyzed. We recorded the length of time between symptom onset and diagnosis, visual acuity, intraocular pressure, clinical findings of the anterior and posterior segments of the eye, fluorescein angiography, systemic diseases, smoking history, and the extent of any ipsilateral carotid artery stenosis. The risk factors for NVG in patients with ocular ischemic syndrome were investigated.

Results

The mean age was 67.9 ± 12.5 years, and 21 men and 4 women were included in this study. At initial examination, the mean logarithm of the minimum angle of resolution (logMAR) was 2.02 ± 1.26, and the mean intraocular pressure was 21.0 ± 10.3 mmHg. Among 25 eyes of the 25 patients, NVG occurred in 17 eyes after a mean period of 12.6 ± 14.0 months. The length of time between symptom onset and diagnosis (p = 0.025) and the extent of ipsilateral carotid artery stenosis (p = 0.032) were identified as significant risk factors for NVG. At the final follow-up, the mean logMAR visual acuity was 3.13 ± 1.24, showing a poor prognosis regardless of whether NVG occurred.

Conclusions

Overall, the prognosis for ocular ischemic syndrome is very poor. The risk of NVG increases with the length of time between symptom onset and diagnosis, as well as with the severity of ipsilateral carotid artery stenosis.

Complement factor H and LOC387715/ARMS2/HTRA1 variant's frequencies and phenotypic associations in neovascular age-related macular degeneration, a pilot study

Purpose

To evaluate the frequency of 12 single nucleotide polymorphisms (SNPs) of complement factor H (CFH) and LOC387715/ARMS2/HRTA1 and their association with some of the presenting clinical features of neovascular age-related macular degeneration (AMD).

Methods

In this prospective non-comparative case series forty four naïve patients with neovascular AMD were genotyped using sequencing or Sequenom iPLEX technology. Descriptive tests were used for displaying the magnitude of each allele, gender distribution, and age at diagnosis. Fisher exact test was used to evaluate the correlation between visual acuity (VA) and different alleles. Also Kruskal-Wallis test was used for comparison between age at the time of diagnosis and different alleles.

Results

The most frequent SNP among studied patients was rs1061147 with 100% frequency rate. The least common was rs2672598 with a frequency of 52.27%. Only the allele rs800292 of CFH locus on 1q32 was associated with VA better than 20/200 (p value = 0.034). The frequency of this allele was 77.27% (34 patients) in this study. There was no significant association between any of alleles, and VA worse than 20/200(p > 0.05). Fifteen patients had bilateral exudative AMD (34.09%). There was no significant difference between alleles in bilateral neovascular AMD and unilateral disease. Also bilateral and unilateral patients were not different in terms of age, gender or VA (p value: 0.330, 0.764 and 0.456 respectively). There was also no significant association between any of SNPs and bilaterality of disease.

Conclusion

We designated the frequencies of SNPs of CFH and LOC387715/ARMS2/HRTA1 in neovascular AMD in a sample of Iranian patients. Only the allele rs800292 of CFH locus on chromosome 1q32 was associated with better VA.

CFH polymorphisms in a Northern Spanish population with neovascular and dry forms of age-related macular degeneration

PURPOSE

To elucidate the potential role of single-nucleotide polymorphisms (SNPs) in complement factor H (CFH) gene in Northern Spanish patients with age-related macular degeneration (AMD).

METHODS

A case-control study of 130 unrelated native Northern Spanish diagnosed with AMD (46 dry, 35 neovascular and 49 mixed) and 96 healthy controls matched by age and ethnicity were enrolled. DNA was isolated from peripheral blood and genotyped for AMD-associated SNPs (rs3753394, rs529825, rs800292, rs3766404, rs203674, rs10671170, rs3753396 and rs1065489) using TaqMan probes and restriction fragment length polymorphism (RFLP). The association study was performed using the HaploView 4.0 software.

RESULTS

The allelic frequency analysis revealed that rs529825, rs800292, rs203674 and rs10671170 were significantly associated with an increased risk for AMD. The haplotypes CGG (rs3753394, rs529825 and rs800292) and GCAG (rs203674, rs1061170, rs3753396 and rs1065489) were significantly associated with AMD while the haplotypes CAA (rs3753394, rs529825 and rs800292) and TTAG (rs203674, rs1061170, rs3753396 and rs1065489) were found to be protective. Small differ-ences in allelic frequencies were found between dry and neovascular cases; however, these differences were not significant and did not distinguish one form the other.

CONCLUSIONS

This study found significant association of SNPs rs529825, rs800292, rs203674 and rs1061170 in the CFH gene with susceptibility to AMD. We identified haplotypes that confer protection or increased risk of AMD but not specific genetic variants in CFH capable to distinguish the different clinical forms of AMD in this cohort. Collectively, our results confirmed that CFH represents a strong genetic risk factor for this disease in the Northern Spanish population.