Association of Repeated Intravitreous Bevacizumab Injections With Risk for Glaucoma Surgery

Association Between Glucagon-Like Peptide-1 Receptor Agonists Exposure and Intraocular Pressure Change: GLP-1 Receptor Agonists and Intraocular Pressure Change

PURPOSE

This study evaluates the effects of glucagon-like peptide-1 receptor (GLP-1R) agonists on intraocular pressure (IOP).

DESIGN

Retrospective clinical cohort study.

METHODS

The University of California Health Data Warehouse was queried for patients exposed to GLP-1R agonists or other oral antidiabetics. A total of 1247 glaucoma surgery and treatment naïve eyes of 626 patientson GLP-1R agonists and 1083 glaucoma surgery and treatment naïve eyes of 547 patients on other oral antidiabetics were included. Index date was defined as the date of first exposure to the medication. Eyes with at least one pre-exposure and one post-exposure tonometry records within 365 days of the index date were included. Clinical and laboratory data were extracted. Eyes were excluded upon exposure to glaucoma hypotensive medication or glaucoma surgery. The primary outcome measure was ∆IOP after exposure, which was analyzed using a paired t test and generalized estimating equations (GEE) RESULTS: The median age was 66.2 years [IQR = 18.3]; 607 (51.7%) were female, and 667 (56.9%) were Caucasian. Median pre-exposure IOP, hemoglobin A1c, and body mass index were 15.2 mm Hg [IQR = 3.8], 7.5 [IQR = 2.4], and 29.8 [IQR = 9.4], respectively. A total of 776 individuals (66.1%) had diabetes, with the median number of active oral antidiabetics being 1.0 [IQR = 1.0], and 441 (37.5%) being insulin users. Several pre-exposure characteristics differed between the groups. The mean ∆IOP was -0.4 ± 2.8 mm Hg (paired t test P < .001) and -0.2 ± 3.3 mm Hg (paired t test P = .297) in the GLP-1R agonist and other antidiabetics groups, respectively. Pre-exposure IOP was the only independent predictor of ΔIOP in multivariable GEE. Sensitivity analyses yielded similar results.

CONCLUSIONS

Although GLP-1R agonists were significantly associated with a decrease in IOP in the paired analysis, they were not associated with ΔIOP in multivariable GEE. Moreover, the difference in ΔIOP between the two groups was small.

Medications for attention deficit hyperactivity disorder associated with increased risk of developing glaucoma

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) therapies including atomoxetine, methylphenidate, and amphetamines are some of the most prescribed medications in North America. Due to their sympathomimetic action, these drugs are contraindicated in patients with a history of angle closure glaucoma (ACG). This study aims to determine the risk of ACG and open angle glaucoma (OAG) among users of these treatments.

METHODS

This is a retrospective cohort study with a case control analysis using the PharMetrics Plus Database (IQVIA, USA). We created a cohort of new users of atomoxetine, methylphenidate, and amphetamines and they were followed to the first diagnosis of (1) ACG or OAG; or (2) end of follow up. For each case, four age-matched controls were selected. A conditional logistic regression model was used to adjust for confounders and to calculate adjusted incidence-rate-ratios (aIRRs).

RESULTS

A total of 240,257 new users of the ADHD medications were identified. The mean age was 45.0 ± 19.4 years and 55% of the cohort was female. Regular users of atomoxetine and amphetamines had a higher aIRR for developing ACG compared with non-users (aIRR = 2.55 95% CI [1.20-5.43] and 2.27 95% CI [1.42-3.63], respectively); while users of methylphenidate had a higher aIRR for developing OAG (aIRR = 1.23 95% CI [1.05-1.59]).

CONCLUSIONS

Use of amphetamines and atomoxetine had a higher risk for ACG, while use of methylphenidate was associated with a higher risk for OAG. Given the prevalence of ADHD medication use (medically and recreationally), our current data on their associated risk of glaucoma have profound public health implications.

Optimizing open-angle glaucoma risk assessment in patients with retinal vein occlusions

PURPOSE

To evaluate factors associated with the diagnosis of open-angle glaucoma (OAG) after a retinal vein occlusion (RVO).

DESIGN

Retrospective, cross-sectional study.

METHODS

Patients diagnosed with OAG after RVO were matched 2:1 with RVO patients without prior glaucoma. Logistic regression identified factors linked to OAG diagnosis.

RESULTS

Of 1178 RVO patients without initial OAG, 51 (4.5%) were later diagnosed with OAG after an average of 5.5 ± 6.1 years. Screening tests for OAG were performed at a higher frequency in patients diagnosed with OAG compared with patients who never received this diagnosis (visual field [VF] testing 21.6% versus 10.8% (P = 0.073) and retinal nerve fiber layer [RNFL] imaging 52.9% versus 27.4% (P = 0.002), respectively). At the time of the first VF obtained after RVO, mean deviation averaged -10.3 dB in the affected eyes, compared with -5.0 dB in the fellow eyes (P < 0.001); in contrast, RNFL thickness was similar between eyes at the time of OAG diagnosis (72 µm versus 74 µm, P = 0.290). Predictive factors for OAG diagnosis included higher intraocular pressure (IOP) and cup-to-disc ratio (CDR) in the unaffected eye, and the absence of macular edema in the RVO-affected eye (R2 = 0.375, P < 0.001).

CONCLUSIONS

OAG is a significant risk factor for RVO. Our study reveals a reciprocal relationship between RVO and the development of OAG, highlighting the need for glaucoma risk assessment in all patients with RVOs to avoid delays in diagnosis and vision loss from glaucoma.

Association between Glucagon-Like Peptide 1 (GLP-1) Receptor Agonists Exposure and Intraocular Pressure Change

Objective

This study aims to provide data on the effects of glucagon-like peptide 1 receptor (GLP-1R) agonists on intraocular pressure (IOP).

Design

Retrospective cohort study.

Subjects Participants and/or Controls

1247 glaucoma surgery and treatment naïve eyes of 626 patients who were initiated on GLP-1R agonists compared to 1083 glaucoma surgery and treatment naïve eyes of 547 patients who were initiated on other oral antidiabetics.

Methods Intervention or Testing

The University of California Health Data Warehouse was queried for patients exposed to GLP-1R agonists or other oral antidiabetics. Index date was defined as the date of first exposure to the medication. Eyes with at least one pre-exposure and one post-exposure tonometry record within 365 days of the index date were included in the analysis. Clinical and laboratory data elements were extracted from the database. Eyes were censored from the analysis upon exposure to glaucoma hypotensive medication or glaucoma surgery. ΔIOP was analyzed using a paired t-test. Regression analysis was conducted using generalized estimating equations (GEE) accounting for inter-eye correlation. Sensitivity analyses were performed to assess the robustness of the findings.

Main Outcome Measures

Primary outcome measure was ΔIOP after exposure to the medication.

Results

The median age of all included subjects was 66.2 years [IQR=18.3]; 607 (51.7%) were female, and 667 (56.9%) were Caucasian. Median pre-exposure IOP, HbA1c, and BMI were 15.2 mmHg [IQR=3.8], 7.5 [IQR=2.4], and 29.8 [IQR=9.4], respectively. 776 individuals (66.1%) had diabetes, with the median number of active oral antidiabetics being 1.0 [IQR=1.0], and 441 (37.5%) being insulin users. Several pre-exposure characteristics significantly differed between the GLP-1R agonist and the control group. The mean ΔIOP was -0.4±2.8 mmHg (paired t-test p<0.001) and -0.2±3.3 mmHg (paired t-test p = 0.297) in the GLP-1R agonist and other antidiabetics groups, respectively. Pre-exposure IOP was the only independent predictor of ΔIOP in multivariable GEE. Sensitivity analyses yielded similar results.

Conclusions

Although GLP-1R agonists were significantly associated with a decrease in IOP in the paired analysis, they were not associated with ΔIOP in multivariable GEE. Moreover, the difference between the ΔIOP in the two groups was small. Future prospective studies following a standardized dose and delivery method may provide further insights.

Ganglion cell complex changes in wet AMD patients treated with anti-VEGF intravitreal injections according to a treat-and-extend protocol

OBJECTIVE

To analyze changes in ganglion cell complex (GCC) thickness in wet age-related macular degeneration (AMD) patients receiving intravitreal injections.

DESIGN

Retrospective cohort study involving 46 eyes at a single tertiary ophthalmology practice.

PARTICIPANTS

The injection group consisted of wet AMD patients who received intravitreal injections for at least 3 years following a treat-and-extend protocol. Twenty-two patients received ranibizumab, and 1 patient received aflibercept. The control group consisted of dry AMD patients who were observed only and did not receive medical treatment over the same period. GCC thickness and visual acuity were recorded at baseline and at 1-, 2-, and 3-year follow-up visits.

RESULTS

In the injection group, there was a nonsignificant trend toward reduction in GCC thickness over 3 years (-4.09 ± 8.47 µm; p = 0.09). Within the injection group, correlation analysis between the number of intravitreal injections and GCC thickness was nonsignificant but trended toward a direct relationship, with more injections correlated with a relatively thicker GCC at 3 years. There was no significant change in GCC thickness between baseline and year 3 for the control group.

CONCLUSIONS

Study results suggest that that there is no significant GCC thinning in wet AMD patients following a treat-and-extend regimen over 3 years.

Acrizanib as a Novel Therapeutic Agent for Fundus Neovascularization via Inhibitory Phosphorylation of VEGFR2

Purpose

The present study aimed to evaluate the effect of acrizanib, a small molecule inhibitor targeting vascular endothelial growth factor receptor 2 (VEGFR2), on physiological angiogenesis and pathological neovascularization in the eye and to explore the underlying molecular mechanisms.

Methods

We investigated the potential role of acrizanib in physiological angiogenesis using C57BL/6J newborn mice, and pathological angiogenesis using the mouse oxygen-induced retinopathy (OIR) and laser-induced choroidal neovascularization (CNV) models. Moreover, vascular endothelial growth factor (VEGF)-treated human umbilical vein endothelial cells (HUVECs) were used as an in vitro model for studying the molecular mechanism underlying acrizanib's antiangiogenic effects.

Results

The intravitreal injection of acrizanib did not show a considerable impact on physiological angiogenesis and retinal thickness, indicating a potentially favorable safety profile. In the mouse models of OIR and CNV, acrizanib showed promising results in reducing pathological neovascularization, inflammation, and vascular leakage, indicating its potential efficacy against pathological angiogenesis. Consistent with in vivo results, acrizanib blunted angiogenic events in VEGF-treated HUVECs such as proliferation, migration, and tube formation. Furthermore, acrizanib inhibited the multisite phosphorylation of VEGFR2 to varying degrees and the activation of its downstream signal pathways in VEGF-treated HUVECs.

Conclusions

This study suggested the potential efficacy and safety of acrizanib in suppressing fundus neovascularization. Acrizanib functioned through inhibiting multiple phosphorylation sites of VEGFR2 in endothelial cells to different degrees.

Translational Relevance

These results indicated that acrizanib might hold promise as a potential candidate for the treatment of ocular vascular diseases.

[Topical application of hypotensive drugs for the prevention of intraocular pressure elevation after intravitreal injections of anti-VEGF drugs]

The management protocol for patients with neovascular age-related macular degeneration (nAMD) involves multiple intravitreal injections (IVI) of anti-VEGF drugs. The ability to reduce the peak intraocular pressure (IOP) rise is greatly important in clinical practice.

PURPOSE

This study evaluates the effect of topical hypotensive drugs on the short-term IOP rise after IVI of anti-VEGF drugs in patients with nAMD.

MATERIAL AND METHODS

The prospective study included 80 patients with newly diagnosed nAMD. Before the start of treatment, the patients were divided into 4 groups of 20 people each: 1st - controls, who received no prophylactic drugs, in the 2nd, 3rd and 4th groups local instillations of one drop of hypotensive drugs brinzolamide 1%, brinzolamide-timolol, brimonidine-timolol were performed in the conjunctival sac twice: 1 day before the injection (at 20:00) and on the day of the injection 2 hours before the manipulation (at 08:00), respectively. IOP was measured in each patient using ICare Pro non-contact tonometer before injection, as well as 1 min, 30 and 60 min after injection.

RESULTS

Prophylactic use of hypotensive drugs was associated with a significant decrease in IOP immediately after IVI compared to the same parameter in the 1st group (p<0.001), the maximum decrease in IOP values was observed when using a fixed combination of brimonidine-timolol by 12.1 mm Hg compared to the controls (p<0.001), the combination of brinzolamide-timolol reduced IOP by 8.5 mm Hg (p<0.001), brinzolamide 1% led to the smallest decrease in IOP - by 5.1 mm Hg (p<0.001).

CONCLUSION

Study patients that received instillations of brimonidine-timolol combination of one drop into the conjunctival sac 1 day before the injection and on the day of the injection showed the maximum decrease in IOP compared to patients of the other groups.

Accuracy, Precision, and Residual Volume of Commonly Used Syringes for Intravitreal Injections and the Impact on Intraocular Pressure

PURPOSE

To compare accuracy, precision, and residual volume of commonly used syringes for intravitreal injections (IVIs) and to assess the intraocular pressure (IOP) rise by variations in volumes delivered.

DESIGN

Experimental laboratory study.

SUBJECTS

No subjects were involved in this study.

METHODS

We tested 8 syringe models with 2 different needle setups, with 2 different solutions (distilled water or glycerin) and target volumes (50 and 70 μL). To obtain the delivered and residual volumes, we weighed the syringe-needle setups with scale before liquid withdrawal, with liquid, and after liquid release. We also created an experimental eye model to determine the transient rise in IOP following stepwise 10-μL increases in injection volumes.

MAIN OUTCOME MEASURES

Delivered and residual volumes, IOP rise.

RESULTS

We tested a total of 600 syringe-needle setups. Becton Dickinson (BD) Ultra-Fine (0.34 ± 0.28 μL), Zero Residual (1.53 ± 1.15 μL), and Zero Residual Silicone Oil-free (1.40 ± 1.16 μL) syringes showed the lowest residual volume (P < 0.001) in comparison with the others (range: 24.86 ± 1.78 μL for Injekt-F to 51.97 ± 3.37 μL for Omnifix-F). The most accurate setups were (percentage deviation from target volume): Zero Residual Silicone Oil-free (+ 0.70%), Zero Residual 0.3 ml (+ 4.49%), BD Ultra-Fine (+ 7.83%), Injekt-F (9.42%), Norm-Ject (+ 15.88%), Omnifix-F (+ 16.96%), BD Plastipak Brazil (+17.96%), and BD Plastipak Spain syringes (+ 19.41%). There was a statistically significant difference between the Zero Residual Silicone Oil-free syringe and all other syringes (P < 0.0001), except for the Zero Residual 0.3-ml syringe (P = 0.029). The coefficient of variation was low for all syringes. The modeled IOP rise ranged from 32.3 (standard deviation [SD], 1.4) mmHg for 20-μL injection volume to 76.5 (SD, 1.0) mmHg for 80-μL injection volume. For the standard 50-μL injection volume, the peak pressure was 50.7 (SD, 0.1) mmHg, and the pressure rise duration was 28 (SD, 2) minutes.

CONCLUSIONS

There were significant differences in accuracy and residual volume between syringes, whereas they showed a high precision. Volume excess results in a considerable increase in IOP rise after injection. These findings may provide a relevant overview to clinicians and to both device and drug manufacturers regarding pharmacoeconomic, safety, and efficacy issues.

FINANCIAL DISCLOSURE(S)

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

Exploring the Relationship between Anti-VEGF Therapy and Glaucoma: Implications for Management Strategies

A short-term increase in intraocular pressure (IOP) is a common side effect after intravitreal anti-VEGF therapy, but a sustained increase in IOP with the development of secondary glaucoma has also been reported in some studies after repeated intravitreal anti-VEGF injections. The aim of this review is to present and discuss the possible pathophysiological mechanisms and factors contributing to a sustained rise in IOP, as well as treatment strategies for patients at risk. Close monitoring and adjustable IOP-lowering treatment are recommended for high-risk patients, including those with glaucoma, angle-closure anomalies, ocular hypertension or family history of glaucoma; patients receiving a high number of injections or at shorter intervals; and patients with capsulotomy. Strategies are needed to identify patients at risk in a timely manner and to prevent sustained elevation of IOP.

Clinical Features Associated with Acute Elevated Intraocular Pressure After Intravitreal Anti-VEGF Injections

Purpose

To study the effects of intravitreal injection (IVI) of anti-VEGF (vascular endothelial growth factor) agents on intraocular pressure (IOP) and find associations with acute pressure spikes.

Methods

This was a three-month, prospective study of patients receiving outpatient IVI of anti-VEGF agents for diabetic retinopathy (DR), age-related macular degeneration (AMD), and retinal vein occlusion (RVO) at the Acuity Eye Group Medical Centers. IOP was measured pre- and post-injection at 10-minute intervals up to 50 minutes after injection with a handheld tonometer. Patients with an IOP greater than 35 mmHg at 30 minutes received an anterior chamber paracentesis (ACP), while patients below 35 mmHg were monitored without intervention.

Results

A total of 617 patients (51% female, 49% male) received IVI for DR (n = 199), AMD (n = 355), and RVO (n = 63). ACP was performed in 17 patients. Average pre-injection IOP was 16 ± 4 compared to 24 ± 7 mmHg for the non-ACP vs ACP group, respectively (mean ± standard deviation), p < 0.0001. IOP returned to baseline in 98% of patients at 50 minutes. A diagnosis of glaucoma and glaucoma suspect was more prevalent in the ACP group compared to the non-ACP group, 82.3% vs 14.2% and 17.6% vs 9.0%, respectively, p < 0.0001 and p > 0.05. Patients with a pre-injection IOP >25 mmHg and a history of glaucoma had a 58.3% rate of ACP. A 31-gauge needle had a higher mean increase in IOP from baseline compared to 30-gauge needle, p < 0.0001.

Conclusion

IOP spikes are most significant in the first 10 minutes after IVI but typically resolve within the first hour. However, utilizing a smaller 31-gauge IVI in patients with a glaucoma history and pre-injection IOP >25 mmHg may be associated with significant IOP spikes lasting longer than 30 minutes.

The Impact of Intraocular Treatment on Visual Acuity of Patients Diagnosed with Branch Retinal Vein Occlusions

Branch retinal vein occlusions are a significant cause of vision loss and present several ophthalmic and systemic risk factors, including age, hypertension, hyperlipidemia and glaucoma. Retinal vein occlusion is the second-most-common retinal vascular disease. This study evaluated the effects of Ozurdex in contrast to a combination therapy with anti-vascular endothelial growth factor (VEGF) and cortisone in treatment-naive branch retinal vein occlusions-macular edema (BRVO-ME) cases, at 4-month and 6-month follow-ups. Thirty eyes were included in the study, which were divided into two groups. The first group consisted of 15 eyes, and each received 1 injection of dexamethasone intravitreal implant Ozurdex (DEX). The second group of 15 eyes received 3 intravitreal injections, the first and second with the anti-vascular endothelial growth factor aflibercept and the third one with 4 mg of triamcinolone acetonide (Vitreal S), spaced at one month. The best corrected visual acuity (BCVA) results suggested that the peak efficacy was at 4 months for both groups, with mean values of 0.5 LogMAR and 0.4 LogMAR. Regarding macular edema, there were no significant changes between the 4- and 6-month follow-up periods, with mean values of 361 μm and 390 μm. Six patients experienced transient raised intraocular pressure at one week after treatment. This study highlights the benefits to visual acuity of the combination of anti-vascular endothelial growth factor and cortisone, which represents a viable solution with similar results to Ozurdex therapy.

Risk of Intraocular Pressure Increase With Intravitreal Injections of Vascular Endothelial Growth Factor Inhibitors: A Cohort Study

PURPOSE

Intraocular pressure increase (IOPi) after intravitreal injections of vascular endothelial growth factor inhibitors (VEGFis) might be different among different VEGFis (bevacizumab, aflibercept, ranibizumab). The purpose of this study was to evaluate the risk of IOPi among new users of bevacizumab, ranibizumab, and aflibercept in nondiabetic patients in Tuscany, Italy.

DESIGN

Retrospective cohort study.

METHODS

Tuscan regional administrative database was used to identify subjects with a first VEGFi intravitreal injection between 2011 and 2020, followed to first incidence of IOPi. Diabetic subjects, those with pre-existing IOPi, or previous use of dexamethasone implants were excluded. Multivariable Cox regression analyses (intention-to-treat and as treated) were conducted to evaluate risk of IOPi among aflibercept, bevacizumab, and ranibizumab, adjusting for potential confounding variables. IOPi was defined as the first record of International Classification of Diseases, Ninth Revision (ICD-9-CM) code 365 or use of 2 glaucoma drugs dispensations within 180 days of each other.

RESULTS

We identified 6585 new users of VEGFis: 1749 aflibercept, 1112 bevacizumab, and 3724 ranibizumab. Women made up 60% of the cohort, with a mean age of 73.6 years. In the intention-to-treat analysis, the adjusted hazard ratio (HR) for incident IOPi, compared with aflibercept, was higher for bevacizumab (HR = 2.20, 95% CI = 1.64-2.95) and ranibizumab users (HR = 1.88, 95% CI = 1.46-2.42), respectively. The HRs remained robust after exclusion of patients with proxy of retinal vascular occlusion. As treated analysis confirmed such results (bevacizumab: HR = 3.76, 95% CI = 2.30-6.17; ranibizumab: HR = 2.49, 95% CI = 1.62-3.82).

CONCLUSIONS

This study found an increased risk of IOPi among nondiabetic patients with ranibizumab and bevacizumab compared with aflibercept. Future studies are needed to validate these findings.

Incidence of ocular hypertension after anti-VEGF injections: examining the effect of drug filtration and silicone-free syringes

OBJECTIVE

To examine the difference in incidence of ocular hypertension (OHT) following the introduction of filtered anti-vascular endothelial growth factor (anti-VEGF) medication in silicone-free syringes.

DESIGN

Retrospective cohort study.

METHODS

A retrospective review of consecutive treatment-naive patients receiving intravitreal anti-VEGF injections in a group practice was performed. Data from the cohort receiving nonfiltered anti-VEGF in insulin syringes (IS group) was collected from June 2015. Data from the cohort receiving filtered anti-VEGF in silicone-free syringes (SFS group) was collected from June 2019. Follow up data were collected at 1 year. Exclusion criteria included prior anti-VEGF treatment, known glaucoma or diagnosis of glaucoma suspect before anti-VEGF treatment, neovascular glaucoma, steroid use, or vitrectomy during follow-up. Primary outcome was the cumulative incidence of intraocular pressure (IOP) > 21 mmHg and IOP ≥ 30 mm Hg at any follow-up visit. The use of IOP lowering therapy was also recorded.

RESULTS

The mean age (71 ± 13 years), mean number of injections (9.6 ± 2.7), and median follow-up time (392 ± 57 days) were similar between groups. The incidence of IOP ≥ 21 mm Hg was 34% (34/100) in the IS group and 15% (15/100) in the SFS group (p = 0.025). The incidence of IOP ≥ 30 mm Hg was 8% (8/100) in the IS group and 0% (0/100) in the SFS group (p =0.004). The incidence of IOP-lowering therapy was 13% in the IS group and 0% in the SFS group (p =0.0002).

CONCLUSION

The incidence of OHT and treatment with IOP-lowering therapy significantly decreased after the introduction of filtered anti-VEGF medication and silicone-free syringes.

Deformation of Aflibercept and Ranibizumab Syringes Causes Variation in Intravitreal Injection Volume and Risks Retinal Tear Formation

PURPOSE

The intravitreal injection volume is known to vary with plunger alignment and the speed of injection. We investigated the role that syringe stopper deformation plays in allowing excess volumes to be injected into the eye and the potential for the vitreous humor to become incarcerated when excess force is released within the eye.

DESIGN

Experimental study.

METHODS

Aflibercept prefilled syringes (PFSs), ranibizumab PFSs, and 1-ml tuberculin (TB) syringes were subjected to increasing injection force to assess the extent to which each design allowed for excess volumes to be expelled after the stopper reached the bottom of the syringe barrel (i.e., after the 50-μl dose was expelled).

MAIN OUTCOME MEASURES

Additional volume expelled with stopper deformation.

RESULTS

Syringe stoppers are capable of deformation into the dead space when additional force is applied. This allows for progressively greater medication doses to be administered. At an additional force of 3.92 N after the syringe stopper came in contact with the bottom of the syringe barrel, the aflibercept PFSs, ranibizumab PFSs, and 1-ml TB syringes dispensed an additional 17.2%, 11.4%, and 0.8% higher volume than the intended volume of 50 μl, respectively. Upon release of this force, a proportional volume was observed to be drawn back into the needle.

CONCLUSIONS

The intravitreal injection volume varies with the force applied to fully depressed syringes because of syringe stopper deformation. We advise that performing forceful intravitreal injections be avoided to prevent excessive dosing of medication. We also caution that pressure applied to the plunger during intravitreal injections not be released while the needle is in the vitreous cavity to guard against vitreous incarceration, which could lead to retinal tear formation or detachment.

Glaucoma progression in patients receiving intravitreal anti‐VEGF treatment for neovascular age‐related macular degeneration

PURPOSE

The purpose of this study was to investigate how often glaucoma and neovascular age-related macular degeneration (nAMD) occur in the same patient and to evaluate whether glaucoma progression is faster in eyes treated with intravitreal anti-VEGF medications for nAMD.

METHODS

This single-centre retrospective real-world data (RWD) consists of medical records of 6314 glaucoma and 2166 nAMD patients treated in 2008-2017 in Tays Eye Centre, Finland. To study glaucoma progression, changes in visual fields (mean deviation [MD], dB/year), IOP (mmHg/year) and fundus photographs (progression, yes/no) were compared in glaucoma eyes with and without anti-VEGF treatment for nAMD and ≥1 year follow-up.

RESULTS

During the 10-year period, 147 patients with glaucoma received intravitreal anti-VEGF treatment for nAMD corresponding to 2% of glaucoma and 7% of nAMD patients. The mean change in MD was -0.70 dB/year (SD 1.8) vs. -0.27 dB/year (SD 1.7) (p = 0.027) in glaucoma eyes with (n = 37) and without (n = 4304) anti-VEGF injections, respectively. In patients with bilateral glaucoma and unilateral nAMD treated with anti-VEGF injections (n = 20), MD declined at -0.62 dB/year (SD 1.9) vs 0.33 dB/year (SD 1.5) (p = 0.654), and glaucoma progression was detected in 14/20 vs 10/20 (p = 0.219) fundus photographs in eyes with anti-VEGF treatment compared with their untreated fellow eyes.

CONCLUSION

nAMD and glaucoma were found co-existing in the same eye at rates that were similar to the age-corrected prevalence of the two diseases in the general population. Our results suggest that intravitreal anti-VEGF treatment for nAMD may accelerate glaucoma progression.

Intraocular pressure decreases in eyes with glaucoma-related diagnoses after conversion to aflibercept for treatment-resistant age-related macular degeneration

OBJECTIVE

To understand intraocular pressure (IOP) response after switching from intravitreal bevacizumab (IVB) and/or ranibizumab (IVR) to intravitreal aflibercept (IVA) for treatment-resistant neovascular age-related macular degeneration (nAMD) in patients with and without coexisting glaucoma-related diagnoses.

METHODS

Retrospective, cross-sectional comparative case series of 62 eyes of 58 patients treated with intravitreal injection for nAMD from March 2010 to April 2018. Patients with glaucoma-related diagnoses, defined here as open-angle glaucoma or suspicion of open-angle glaucoma, ocular hypertension, and/or narrow-angle glaucoma, were compared to those without glaucoma. IOP data were collected at baseline, at the three visits where patients received loading doses of IVB/IVR, and at all of the visits following the switch to IVA through the end of follow-up.

RESULTS

19 eyes with pre-existing glaucoma-related diagnoses were compared to 43 eyes without such diagnoses. Baseline IOP was similar for glaucoma and non-glaucoma patients. The loading doses of IVB/IVR did not impact IOP; however, a small, sustained rise in IOP was noted among patients with glaucoma-related diagnoses by the final IVB/IVR injections before the switch to IVA (∆IOP 1.61 ± 0.52 mmHg, P < 0.002). After conversion to IVA, pre-injection IOP declined in eyes both with (-1.59 ± 0.54 mmHg, P < 0.001) and without (-0.99 ± 0.28 mmHg, P < 0.001) glaucoma-related diagnoses.

CONCLUSIONS

IOP in patients with glaucoma-related diagnoses appears to be more sensitive to intravitreal injections than it is in patients without glaucoma-related diagnoses. It rises with IVB/IVR and declines after the switch to IVA. Switching patients with nAMD to IVA may present an opportunity to lower IOP in patients with glaucoma.

Ocular and Systemic Factors Associated with Glaucoma

Glaucoma is one of the leading causes of irreversible blindness in the world. Although numerous factors have been implicated in the pathogenesis of glaucoma, the main focus of management still remains lowering the intraocular pressure (IOP) by medical or surgical therapy. However, a major challenge is that many glaucoma patients continue to progress despite good control of IOP. In this regard, the importance of other coexisting factors that may contribute to disease progression needs to be explored. Ophthalmologists need to be aware of ocular risk factors and the impact of systemic diseases and their medications, along with lifestyle modifications on the course of glaucomatous optic neuropathy and adopt a holistic approach in treating the eye as well as the patient to alleviate the suffering from glaucoma in a comprehensive manner.

How to cite this article

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

A Novel Hypoxia-inducible Factor 1α Inhibitor KC7F2 Attenuates Oxygen-induced Retinal Neovascularization

Purpose

KC7F2 is a novel molecule compound that can inhibit the translation of hypoxia-inducible factor 1α (HIF1α). It has been reported to exhibit potential antiangiogenic effect. We hypothesized that KC7F2 could inhibit oxygen-induced retinal neovascularization (RNV). The purpose of this study was to investigate this assumption.

Methods

Oxygen-induced retinopathy (OIR) models in C57BL/6J mice and Sprague-Dawley rats were used for in vivo study. After intraperitoneal injections of KC7F2, RNV was detected by immunofluorescence and hematoxylin and eosin staining. Retinal inflammation was explored by immunofluorescence. EdU incorporation assay, cell counting kit-8 assay, scratch test, transwell assay, and Matrigel assay were used to evaluate the effect of KC7F2 on the proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVEC) induced by vascular endothelial growth factor (VEGF) in vitro. Protein expression was examined by Western blot.

Results

KC7F2 treatment (10 mg/kg/d) in OIR mice significantly attenuated pathological neovascularization and decreased the number of preretinal neovascular cell nuclei, without changing the avascular area, which showed the same trends in OIR rats. Consistently, after the KC7F2 intervention (10 µM), cell proliferation was inhibited in VEGF-induced HUVEC, which was in agreement with the trend observed in the retinas of OIR mice. Meanwhile, KC7F2 suppressed VEGF-induced HUVEC migration and tube formation, and decreased the density of leukocytes and microglia colocalizing neovascular areas in the retinas. Moreover, the HIF1α–VEGF pathway activated in retinas of OIR mice and hypoxia-induced HUVEC, was suppressed by KC7F2 treatment.

Conclusions

The current study revealed that KC7F2 was able to inhibit RNV effectively via HIF1α–VEGF pathway, suggesting that it might be an effective drug for RNV treatment.

Effects of Postoperative Intravitreal Injections on Outcomes of Traditional Glaucoma Surgery in Patients with Preoperative Intravitreal Injections

PURPOSE

To compare outcomes of glaucoma drainage device (GDD) implantation and trabeculectomies with and without postoperative intravitreal injections (IVIs) in glaucoma patients with a history of preoperative IVIs.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 133 eyes of 133 glaucoma patients who underwent GDD implantation or trabeculectomy with at least 1 IVI preoperatively between January 2005 and October 2020 at Massachusetts Eye and Ear.

METHODS

Chart review of glaucoma patients with traditional glaucoma surgery and at least 1 IVI before surgery. All statistical analyses were conducted with R statistical programming software.

MAIN OUTCOME MEASURES

Intraocular pressure (IOP), medication burden, best-corrected visual acuity (BCVA), Kaplan-Meier success rates, adjusted hazard ratios (HRs), and complications.

RESULTS

Baseline demographics were similar between the groups with and without postoperative IVIs. The group with postoperative IVIs had a higher proportion of diabetic retinopathy and retinal vascular occlusions than the group without postoperative IVIs, which had more eyes with age-related macular degeneration. Intraocular pressure, medication burden, and visual acuity were similar between groups at all time points except for IOP at 6 weeks, which was lower in the group with postoperative IVIs. The group with postoperative IVIs had significantly more preoperative IVIs than the group without postoperative IVIs (6.6 vs. 3.3, P = 0.017). For success defined as IOP reduction ≥ 20% with 5 < IOP ≤ 21 mmHg, Kaplan-Meier analyses demonstrated similar success rates between groups with and without IVIs. When stratified by the number of IVIs, success rates for the group with 7 or more IVIs were significantly higher than the success rates for the group with 0-6 IVIs (P = 0.005). Each additional postoperative IVI resulted in a 7.2% decrease in the hazard of failure to achieve our stated success criteria. With regard to late complications, the group with postoperative IVIs had a higher incidence of vitreous hemorrhage (18.5% vs. 3.2%, P = 0.039) than the group without postoperative IVIs.

CONCLUSIONS

A higher number of postoperative IVIs, specifically 7 or more IVIs, may be associated with improved success rates of traditional glaucoma surgery in glaucoma patients who received IVIs before surgery.

Efficacy of Intravitreal Injection of Filtered Modified Low-Dose Triamcinolone Acetonide and Ranibizumab on Pseudophakic Cystoid Macular Edema

Purpose

To compare the visual and morphological effects between intravitreal injection of filtered modified 2 mg triamcinolone acetonide (TA) and 0. 5 mg ranibizumab in patients with pseudophakic cystoid macular edema (PCME).

Methods

A retrospective, interventional study was conducted from January 2015 to February 2020 involving patients with PCME after uneventful cataract surgery. A total of 25 patients (25 eyes) with PCME received an intravitreal injection of 0.22 μm filtered modified 2 mg TA, while 15 patients (15 eyes) received 0.5 mg ranibizumab injection. Central macular thickness (CMT), best-corrected visual acuity (BCVA), intraocular pressure (IOP), times of repeated injections, and other side effects were observed at 2 weeks, 1 month, 3 months, and 6 months after injection; then, the data were compared with preinjection information in each group and between the two groups.

Results

Both the TA and ranibizumab intravitreal injection can achieve improved BCVA and reduced CMT in patients with PCME (P < 0.05), with a trend toward greater improvement in the TA group, but the difference was only significant at 3 months (P < 0.05). IOP was in the normal range without any significant difference (P > 0.05). Thirty-three percent of patients in the ranibizumab group required repeated intravitreal injection compared to 4% in the TA group. Further stratified analysis showed that the better therapeutic effect of the TA group at 3 months after injection only existed in patients with diabetes mellitus (DM), while not in patients without DM. There was no repeat injection in the TA group and 12.5% in the ranibizumab group for patients without DM, while 16.7% in the TA group and 57.1% in the ranibizumab group required repeated injection for patients with DM, which had a significant difference (P < 0.05).

Conclusion

Intravitreal injection of filtered modified 2 mg TA is safe, effective, and an inexpensive alternative to antivascular endothelial growth factor (anti-VEGF) agents for patients with PCME, especially for patients concurrently with DM. A large number of clinical randomized controlled studies along with long-term follow-up observations are needed.

Response of Pediatric Choroidal Neovascularization to Anti-Vascular Endothelial Growth Factor

Choroidal neovascularization (CNV) is a rare condition in children but poses a substantial threat to vision. Anti-vascular endothelial growth factor (anti-VEGF) therapy is commonly used in the pediatric population to treat retinopathy of prematurity. However, the use of anti-VEGF is less common for childhood CNV due to the rarity of CNV in the pediatric population. We report the case of a 10-year-old male presenting with an idiopathic choroidal neovascular membrane. Following a relapse of subretinal fluid after photodynamic therapy, anti-VEGF (bevacizumab) was injected and resulted in remission of the neovascular membrane and improved visual outcome. Further studies are required to elucidate the long-term outcomes associated with the use of anti-VEGF in pediatric patients.

Intraocular Pressure Elevation Following Intravitreal Anti-VEGF Injections: Short- and Long-term Considerations

Published studies agree that transient intraocular pressure (IOP) spikes are common after intravitreal injections of anti-vascular endothelial growth factor agents. Currently, there is no standard of care guiding if and when to prevent these IOP spikes. Furthermore, there are challenges in determining the impact of postinjection IOP elevation on the health of the retinal ganglion cells, particularly given the often-existing comorbidities of retinal and glaucoma pathology. This review highlights the current literature regarding both acute and chronic postinjection IOP elevations and discusses management of postinjection IOP elevation, especially in patients at high risk for glaucomatous damage.

Safety review of anti-VEGF therapy in patients with myopic choroidal neovascularization

INTRODUCTION

Anti-angiogenesis therapy with intravitreal anti-VEGF agents is now the standard-of-care treatment for myopic choroidal neovascularization (CNV).

AREAS COVERED

We provide a critical review of the safety of all the anti-VEGF agents currently used for treating myopic CNV including ranibizumab, aflibercept, conbercept, bevacizumab, and ziv-aflibercept.

EXPERT OPINION

Anti-VEGF therapy for myopic CNV with the currently available anti-VEGF drugs generally have favorable safety outcomes in the short-term. Nonetheless, ocular adverse events following anti-VEGF therapy for myopic CNV may develop and these include worsening or new development of myopic traction maculopathy, increased risk of retinal detachment, and progression of chorioretinal atrophy. Clinicians should be aware of these potential complications and evaluate them before and after anti-VEGF therapy.

Prophylactic effect of brinzolamide-brimonidine fixed combination on intraocular pressure spikes after intravitreal anti-VEGF injections

PURPOSE

To evaluate the effect of topical prophylaxis with brinzolamide-brimonidine fixed combination on short-term intraocular pressure (IOP) elevation after intravitreal injections of anti-vascular endothelial growth factors (anti-VEGF).

METHODS

This prospective comparative study included 56 eyes of 47 patients treated with intravitreal injections of anti-VEGF, and they were randomly divided into two groups. In control group (25 eyes), no prophylactic medication was used, whereas in case group (31 eyes) one drop of a fixed combination of brinzolamide-brimonidine was instilled two hours before the injection. IOP was measured before the injection and at 1 min, 10 min and 30 min post-injection in all eyes.

RESULTS

The mean IOP before injection at 1 min, 10 min and 30 min post-injection was 16,6 ± 2,8 mmHg, 53,4 ± 12 mmHg, 26,4 ± 5,5 mmHg and 17,9 ± 4 mmHg, respectively, in control group and 15,1 ± 3,4 mmHg, 42,6 ± 8,4 mmHg, 21,4 ± 5,5 mmHg and 12,4 ± 3,5 mmHg, respectively, in case group. At 1 min, 10 min and 30 min post-injection, the mean IOP was significantly lower in case group compared with control group (p < 0,001, p = 0,0014 and p < 0,0001, respectively), but no difference at the pre-injection IOP between the two groups was found (p = 0,09).

CONCLUSIONS

The prophylactic administration of one drop of brinzolamide-brimonidine fixed combination significantly reduces the IOP spikes during the first 30 min after the intravitreal anti-VEGF injection.

ACUTE MACULAR AND PERIPAPILLARY ANGIOGRAPHIC CHANGES WITH INTRAVITREAL INJECTIONS

PURPOSE

Intravitreal injections acutely and temporarily increase intraocular pressure (IOP), and this may have cumulative long-term effects including an increased risk for glaucoma surgery. This study was designed to measure retinal perfusion density changes on optical coherence tomography (OCT) angiography and OCT thickness alterations associated with acutely increased IOP after intravitreal injections.

METHODS

Retrospective observational clinical study of 40 eyes (39 patients) with various retinopathies from October 2016 to June 2017 at a tertiary care retina clinic in NYC. Patients were older than 18 years, with vision >20/100, able to fixate and without media opacities precluding OCT angiography, receiving intravitreal bevacizumab or aflibercept for diabetic retinopathy, retinal vein occlusion, macular degeneration, retinal neovascularization, or radiation retinopathy. The 3-mm × 3-mm macular and 4.5-mm × 4.5-mm peripapillary OCT angiography perfusion density, macular OCT thickness, and IOP were measured before and immediately after intravitreal injections. Paired t-test was used to compare preinjection and postinjection values for perfusion density and OCT thickness. Regression analysis was performed for potential effects of baseline IOP, IOP change, and age.

RESULTS

Statistically significant decreases in angiographic perfusion density (P < 0.05) were found in most areas of the superficial and deep layer macular OCT angiography, and the overall optic nerve head and the radial peripapillary capillary layer, preferentially temporal. Macular OCT thickness was significantly decreased in the temporal region and increased in the nasal region. Regression analysis showed relationships between age and decreased superficial macular perfusion. Preinjection IOP was only related to OCT thickness in the fovea. Intraocular pressure change was related only to decreased superficial macular perfusion density.

CONCLUSION

Intravitreal injections produce acute IOP changes that are associated with reduced macular and peripapillary perfusion density. Therefore, it is possible that patients receiving regular intravitreal injections may be sustaining perfusion-related injury to ocular structures that may produce glaucomatous damage to the macula and optic nerve.

EFFICACY OF ADJUVANT TOPICAL DORZOLAMIDE-TIMOLOL IN PATIENTS WITH NEOVASCULAR AGE-RELATED MACULAR DEGENERATION REFRACTORY TO ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY

PURPOSE

To evaluate the efficacy of adjuvant topical dorzolamide-timolol in patients with neovascular age-related macular degeneration unresponsive to anti-vascular endothelial growth factor therapy.

METHODS

This retrospective, interventional study included 15 patients with neovascular age-related macular degeneration refractory to anti-vascular endothelial growth factor. Patients used topical dorzolamide-timolol twice daily in the neovascular age-related macular degeneration eye and received anti-vascular endothelial growth factor therapy at each visit, with the same fixed interval and agent as before the addition of dorzolamide-timolol. Central macular thickness, maximal subretinal fluid height, and maximal pigment epithelial detachment height were measured at baseline and every visit.

RESULTS

The mean follow-up period was 17.2 ± 5.5 weeks. The mean central macular thickness decreased from 383.5 μm at baseline to 298.3 μm at the final visit (P = 0.041). The mean maximal subretinal fluid height decreased from 105.0 μm at baseline to 58.3 μm at the final visit (P = 0.021). Complete resolution of subretinal fluid was observed in 3 of 11 subretinal fluid-type eyes. There was no significant change in the maximal pigment epithelial detachment height. The mean logarithm of the minimum angle of resolution visual acuity decreased from 0.61 (20/81 Snellen) at baseline to 0.66 (20/91 Snellen) at final visit, which was not significant (P = 0.314). The mean intraocular pressure decreased significantly from 14.9 mmHg at baseline to 12.3 mmHg at the final visit (P = 0.005).

CONCLUSION

The use of adjuvant topical dorzolamide-timolol was effective in decreasing central macular thickness and subretinal fluid in patients with neovascular age-related macular degeneration refractory to continual fixed-interval intravitreal anti-vascular endothelial growth factor therapy, but did not result in functional improvement in this short-term study.

Dose-Response Relationship between Intravitreal Injections and Retinal Nerve Fiber Layer Thinning in Age-Related Macular Degeneration

PURPOSE

To determine if multiple intravitreal injections of vascular endothelial growth factor (VEGF) inhibitors for unilateral exudative age-related macular degeneration (eAMD) are associated with thinning of the retinal nerve fiber layer (RNFL), we compared RNFL thickness measurements from the injected eye with that of the fellow eye with nonexudative age-related macular degeneration (neAMD).

DESIGN

Retrospective, cross-sectional study.

PARTICIPANTS

Patients undergoing anti-VEGF therapy for unilateral eAMD.

METHODS

Patients receiving anti-VEGF therapy secondary to eAMD in 1 eye with neAMD in their fellow eye were identified. Patients with a known diagnosis of glaucoma were excluded. Spectral domain OCT measurements of the peripapillary RNFL thickness from both eyes were performed and compared. The differences in the RNFL thickness measurements between eyes were correlated with the number of injections and the duration of therapy.

MAIN OUTCOME MEASURES

Correlation between the number of anti-VEGF injections and peripapillary RNFL thinning.

RESULTS

A total of 108 eyes of 54 patients were evaluated in this study. The average peripapillary RNFL thickness measurements of the injected eye and fellow eye were 87.3 ± 9.6 μm and 89.0 ± 7.5 μm, respectively (P = 0.055). The RNFL thickness difference (fellow eye minus injected eye) was significantly correlated with the number of injections (r = 0.40, P = 0.002) and months of injections (r = 0.38, P = 0.005). The relationship between the difference in the RNFL thickness and the number of injections had a nonlinear dose-response relationship that became apparent after approximately 30 injections and 50 months of injections.

CONCLUSIONS

The difference in RNFL thickness measurements between injected eyes and uninjected fellow eyes was largely within the reported normal limits for interocular differences between healthy eyes. Nevertheless, there was a dose-response relationship between RNFL thinning and number of injections among patients receiving a greater number of injections, suggesting that anti-VEGF injections may have a modest effect on the RNFL thickness after several years of therapy in eyes requiring more anti-VEGF injections; however, we cannot exclude that the RNFL thinning may be secondary to active age-related macular degeneration (AMD) disease progression in both eyes.

Relief of Cystoid Macular Edema-Induced Focal Axonal Compression with Anti-Vascular Endothelial Growth Factor Treatment

Purpose

To evaluate the mechanical compression of retinal nerve fiber layer (RNFL) by intraretinal cysts in macular edema and its relief with anti-vascular endothelial growth factor (anti-VEGF) treatment.

Methods

Optical coherence tomography scans were used to measure RNFL thickness and reflectance at seven preselected points at and around the peak of the edema before and after anti-VEGF treatment in 10 patients (11 eyes) with branch retina vein occlusion (BRVO) and diabetic macular edema (DME). Scans through nonedematous retina and from the fellow eyes were taken as controls. Correlations were sought between the changes in retinal and RNFL thickness, RNFL reflectance, and the size of the intraretinal cysts.

Results

Postinjection RNFL thickness decreased significantly only at peak point of the edema (18.1 ± 2.7 vs. 13.8 ± 1.2 µm; P = 0.038), at its nasal edge (20.1 ± 2.7 vs. 15.5 ± 1.4 µm; P = 0.026), and 500 µm away from its nasal border (35.7 ± 6.0 vs. 20.1 ± 2.7 µm; P = 0.006) suggesting focal stagnation of the axoplasmic flow owing to compression at its peak point. Significant postinjection decreases in RNFL reflectivity were also noted at peak point of the cyst (164.9 ± 10.3 vs. 141.5 ± 12.6 arbitrary units [AU]; P = 0.037), at its nasal edge (166.8 ± 7.8 vs. 135.1 ± 10.2 AU; P = 0.02), and 1500 µm away from temporal edge (160.2 ± 6.2 vs. 141.1 ± 6.4 AU; P = 0.022). Cyst proximity to RNFL (D₅₀ = 50 µm) was the only determinant significantly affecting the magnitude of the RNFL thickness change after anti-VEGF treatment (P = 0.001).

Conclusions

Intraretinal cysts due to BRVO and DME locally compress overlying axons and induce anatomic changes suggestive of axoplasmic stagnation. This compression can be relieved with anti-VEGF treatment.

Translational Relevance

Focal compression of RFNL by retinal cysts may indicate a need for early treatment of macular edema to prevent axonal loss, especially in patients with low axonal reserve

Effects of Intravitreal Anti-VEGF Therapy on Glaucoma-like Progression in Susceptible Eyes

PRéCIS:: Intravitreal anti-vascular endothelial growth factor (VEGF) injections may accelerate glaucomatous change in patients with preexisting glaucoma or ocular hypertension (OHT). The safety of long-term injections in this specific population may be reflected in the need for additional glaucoma interventions.

PURPOSE

The purpose of this study was to investigate whether repeated anti-VEGF injections accelerate structural and functional glaucomatous change in eyes with preexisting glaucoma or OHT.

MATERIALS AND METHODS

This is a retrospective, observational study of injected and noninjected fellow eyes. A total of 28 patients with preexisting glaucoma or OHT, who received ≥6 unilateral anti-VEGF injections for concurrent neovascular retinal disease, were selected for chart review. Primary outcome measures were rate of visual field loss in dB/year, rate of change in retinal nerve fiber layer (RNFL) thickness in microns/year, and need for additional glaucoma medications, surgery, or laser.

RESULTS

The number of eyes requiring additional glaucoma surgery or laser was 8 of 28 (28.6%) for the injected group and 2 of 28 (7.1%) for the noninjected group. A significantly greater proportion of injected eyes required invasive glaucoma intervention (P=0.034). Average rate of decline in mean deviation and change in pattern standard deviation were both significantly greater in injected eyes (P=0.029; P=0.019). Estimated mean rate of global retinal nerve fiber layer change was -4.27 µm/y for the injected group and -1.17 µm/y for the noninjected group and was significant only for injected eyes (P=0.014). Only the superior quadrant exhibited thinning that was significantly different between groups (P=0.030).

CONCLUSIONS

Intravitreal injections were associated with accelerated functional and structural glaucoma-like change in susceptible eyes. Clinicians should assess the need for glaucoma medications or other interventions over the course of anti-VEGF therapy.

Arctiin attenuates high glucose-induced human retinal capillary endothelial cell proliferation by regulating ROCK1/PTEN/PI3K/Akt/VEGF pathway in vitro

Diabetic retinopathy (DR) is one of the most prominent microvascular complications of diabetes, which remains the leading cause of legal blindness in the world. Arctiin, a bioactive compound from Arctium lappa L., has been reported to have antidiabetic activity. In this study, we investigated the effect of arctiin on a human retinal capillary endothelial cell (HRCEC) line and how arctiin inhibits cell proliferation in high glucose (HG)-induced HRCECs. Results showed that arctiin decreased HG-induced HRCECs proliferation in a dose-dependent manner by inducing cell cycle arrest at the G0/G1 phase. Tube formation assay and immunofluorescence staining indicated that arctiin abrogated tube formation induced by HG-induced HRCECs in a dose-dependent manner via down-regulation of VEGF expression. Mechanistic study indicated that perturbation of the ROCK1/PTEN/PI3K/Akt signalling pathway plays a vital role in the arctiin-mediated anti-proliferative effect. Furthermore, pre-incubation of HRCECs with Y-27632 attenuated arctiin-induced cell cycle arrest, cell proliferation and tube formation inhibition. Y-27632 also reversed the activation of PTEN, the inactivation/dephosphorylation of PI3K/Akt and down-regulation of VEGF. Taken together, the results demonstrated that arctiin inhibits the proliferation of HG-induced HRCECs through the activation of ROCK1 and PTEN and inactivation of PI3K and Akt, resulting in down-regulation of VEGF, which inhibits endothelial cell proliferation.

Correlation of ocular rigidity with intraocular pressure spike after intravitreal injection of bevacizumab in exudative retinal disease

BACKGROUND/AIMS

To evaluate the non-invasive measurement of ocular rigidity (OR), an important biomechanical property of the eye, as a predictor of intraocular pressure (IOP) elevation after anti-vascular endothelial growth factor (anti-VEGF) intravitreal injection (IVI).

METHODS

Subjects requiring IVI of anti-VEGF for a pre-existing retinal condition were enrolled in this prospective cross-sectional study. OR was assessed in 18 eyes of 18 participants by measurement of pulsatile choroidal volume change using video-rate optical coherence tomography, and pulsatile IOP change using dynamic contour tonometry. IOP was measured using Tono-Pen XL before and immediately following the injection and was correlated with OR.

RESULTS

The average increase in IOP following IVI was 19±9 mm Hg, with a range of 7-33 mm Hg. The Spearman correlation coefficient between OR and IOP elevation following IVI was 0.796 (p<0.001), showing higher IOP elevation in more rigid eyes. A regression line was also calculated to predict the IOP spike based on the OR coefficient, such that IOP spike=664.17 mm Hg·µL×OR + 4.59 mm Hg.

CONCLUSION

This study shows a strong positive correlation between OR and acute IOP elevation following IVI. These findings indicate that the non-invasive measurement of OR could be an effective tool in identifying patients at risk of IOP spikes following IVI.

Critical analysis of techniques and materials used in devices, syringes, and needles used for intravitreal injections

Intravitreal injections have become the most commonly performed intraocular treatments worldwide. Because intravitreal injections may induce severe adverse events, such as infectious and noninfectious endophthalmitis, cataract, ocular hypertension, vitreous hemorrhage, or retinal detachment, appropriate awareness of the materials and techniques used are essential to reduce these sight-threatening complications. This review provides insights into the needles, syringes, silicone oil coating, sterilization methods, devices to assist intravitreal injections, scleral piercing techniques using needles, syringe handling, anesthesia, and safety issues related to materials and techniques. It is paramount that physicians be aware of every step involved in intravitreal injections and consider the roles and implications of all materials and techniques used. The ability to understand the theoretical and practical circumstances may definitely lead to state-of-the-art treatments delivered to patients. The most important practical recommendations are: choosing syringes with as little silicone oil as possible, or, preferably, none; avoiding agitation of syringes; awareness that most biologics (e.g., antiangiogenic proteins) are susceptible to changes in molecular properties under some conditions, such as agitation and temperature variation; understanding that improper materials and techniques may lead to complications after intravitreal injections, e.g., inflammation; and recognizing that some devices may contribute to an enhanced, safer, and faster intravitreal injection technique.

Incidence of Glaucoma or Ocular Hypertension After Repeated Anti-Vascular Endothelial Growth Factor Injections for Macular Degeneration

Purpose

To estimate the risk of glaucoma or sustained ocular hypertension (OHT) related to anti-vascular endothelial growth factor (VEGF) injections for age-related macular degeneration (AMD).

Design

Retrospective chart review.

Subjects

Patients who received unilateral anti-VEGF injections for AMD at the Wheaton Eye Clinic (IL).

Methods

Chart analysis was performed on 1095 patients, without prior glaucoma or OHT, who received unilateral anti-VEGF injections for AMD from 2005 to 2012, with data collected through 2013. Data collection included demographics, lens status, date and medication type of each injection, and the date of diagnosis of glaucoma or OHT by a treating glaucoma specialist, which was the main outcome measure. Rare events logistic regression was performed to determine the risk of disease development based on sex, lens status, and injection frequency.

Results

Unilateral glaucoma or sustained OHT developed in 42 patients over the course of follow-up, with 40 events in the injected eye only, 2 in the contralateral eye only. Statistical modeling predicted elevated risk for onset of glaucomatous disease with a higher maximum frequency of injections (p < 0.0001, odds ratio [OR] 2.18 for each additional injection over the most injection-intense 6 months for a given subject) and with phakic lens status (p = 0.0009, OR 0.33 for pseudophakia).

Conclusion

Our results show a significant risk for glaucoma or OHT development in patients undergoing repeated treatments with intravitreal anti-VEGF injections for AMD, establishing the first reliable connection between disease development and a period of high-frequency injections. In addition, we show a significantly increased risk of disease development in phakic patients, which we believe points to a mechanical explanation for this type of secondary glaucoma.

Repeated intravitreal injections of antivascular endothelial growth factors and risk of intraocular pressure medication use

PURPOSE

To determine the risk of initiating ocular hypertension and glaucoma treatment with repeated injections of antivascular endothelial growth factors (anti-VEGF).

METHODS

A unique, retrospective cohort study was performed using a large national US medical claim database. The study population included patients who had 1 or more injections of an anti-VEGF agent. Exclusion occurred for any previous glaucoma, glaucoma suspect, glaucoma-related procedure, an ocular steroid injection, or not seeing an eye care provider at least once in each year of follow-up. Cohorts were divided into quartiles based on the number of injections performed over the follow-up period. Patients were observed for 2 and 3 years. The main outcome measure was defined as any new prescription for an ocular antihypertensive medication with a concurrent diagnosis of glaucoma, glaucoma suspect, or ocular hypertension. Multivariate logistic regression determined the odds of initiating glaucoma treatment in each injection quartile while controlling for numerous covariates. Sensitivity analysis assessed outcomes that included new medication only as well as a new medication plus diagnosis of glaucoma.

RESULTS

In total, 17,113 and 9992 patients met 2- and 3-year observation end points, respectively. The multivariate odds ratio for initiating glaucoma treatment at 2 years was higher in the highest quartile (OR 1.96, 95% CI 1.39-2.76, p < 0.001) compared with the lowest. The 3-year comparison had similar results with increased odds in the highest quartile (OR 1.51, 95% CI 1.07-2.13, p = 0.006) compared with the lowest. Sensitivity analyses also showed similar results with more injections being associated with initiating treatment (p < 0.053 for all comparisons).

CONCLUSIONS

Repeated anti-VEGF injections are associated with an increased odds of initiating treatment for ocular hypertension and glaucoma.

Anti-angiogenic and anti-inflammatory effects of CD200-CD200R1 axis in oxygen-induced retinopathy mice model

OBJECTIVE

In this study, the expression changes and the potential effects of CD200 and its receptors during the process of retinal neovascularization (RNV) development had been detected, using a classic oxygen-induced retinopathy (OIR) mice model and CD200Fc (a CD200R1 agonist) intravitreal injection.

MATERIALS AND METHODS

7 day postnatal (P7) C57BL/6J mice were raised in hyperoxia incubators with 75±2% oxygen for 5 days, and returned to room air at P12. All animals were subdivided into three groups: normoxia control, OIR, and OIR+CD200Fc group. The mice of OIR+CD200Fc group were intravitreal injected with CD200Fc (2μg/μL, 0.5μL) at P12. Retinas and vitreous samples were harvested at P17. The expression and localization of CD200 and its receptors were analyzed by Western blot, quantitative real-time polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and retinal whole-mount immunofluorescence. To investigate the effects of CD200Fc treatment, vascular endothelial growth factor (VEGF)-A, platelet-derived growth factor (PDGF)-BB, pro-inflammatory cytokines, NV area, and microglial activation were detected respectively.

RESULTS

In OIR group, both protein and RNA levels of CD200 and CD200R1 were significantly up-regulated. The increased CD200 and CD200R1 were co-localized with Alex594-labeled Griffonia simplicifolia isolectin B4 (IB4) on vascular endothelial cells in NV area of OIR samples, and CD200R1 was co-expressed with ionized calcium-bind adapter molecule 1 (iba1) on microglia in OIR samples at the same time. CD200Fc intravitreal injection could significantly reduce the release of VEGF-A, PDGF-BB, and pro-inflammatory cytokines; shrink the NV area; and inhibit the activation of microglia in OIR mice.

CONCLUSION

These findings suggested that the up-regulation of CD200 and CD200R1 was closely related to RNV development, and the antiangiogenic effects of CD200Fc in OIR model might be realized by inhibition of inflammatory response and microglia activation. The results may provide a new therapeutic target for RNV diseases.

Effect of prior glaucoma surgery on intraocular pressure immediately after anti-vascular endothelial growth factor injection

BACKGROUND

To characterize how prior incisional glaucoma surgery affects the intraocular pressure (IOP) elevation immediately following intravitreal anti-VEGF injections (IVI).

METHODS

Single institution, experimental study. Patients with a history of incisional glaucoma surgery who were receiving anti-VEGF injections were recruited as well as control eyes. Pre- and post-injection IOP measurements were compared as well as time to recovery to within 5 and 10 mmHg of baseline IOP.

RESULTS

Ten eyes with a history of glaucoma surgery and 29 control eyes receiving anti-VEGF injections were included. The most common indication for intravitreal anti-VEGF injection was proliferative diabetic retinopathy in both surgical and control eyes (50% vs 45%, p = 1.00). Post-injection IOP was significantly decreased compared to baseline IOP after anti-VEGF injection in surgical versus control eyes (26.5 ± 8.9 mmHg vs 44.2 ± 8.5 mmHg, respectively, p < 0.001). The mean change in IOP following intravitreal anti-VEGF injection was lower in surgical eyes (10.7 ± 6.6 mmHg vs 28.6 ± 8.3 mmHg, p < 0.001). The mean time for the IOP to return to within 10 mmHg of pre-injection IOP was less in surgical eyes (5.2 ± 4.1 min vs 13.3 ± 7.6 min, p = 0.002).

CONCLUSIONS

Eyes with prior incisional glaucoma surgery demonstrated a significantly lower post-injection IOP elevation and a faster recovery to within 10 mmHg of their pre-injection IOP. Incisional glaucoma surgery may be considered for patients where the attenuation of post-injection IOP elevation is needed and other less invasive measures have failed.

A biocompatible reverse thermoresponsive polymer for ocular drug delivery

Age-related macular degeneration (AMD) is a leading cause of vision loss, the treatment of which may require monthly intravitreal injections. This is a burden on patients and health services, and new delivery modalities that reduce injection frequency are required. To that end, we investigated the suitability of a novel reverse thermoresponsive polymer (RTP) as an ocular drug-delivery vehicle. In this work, we detail the structure and synthesis of a novel RTP, and determine drug release curves for two drugs commonly used in the treatment of AMD, bevacizumab and aflibercept. Biocompatibility of the RTP was assessed in vitro in human and rat cell lines and in vivo following intravitreal injection in rats. Bevacizumab demonstrated a more appropriate release profile than aflibercept, with 67% released within 14 days and 78% released in total over a 183-day period. No toxic effects of RTP were seen in human or rat cells in up to 14 days of co-culture with RTP. Following intravitreal injection, intraocular pressure was unaffected by the presence of RTP and no changes in retinal function or structure were observed at 1 week or 1 month post-injection. RTP injection did not cause inflammation, gliosis or apoptosis in the retina. This work demonstrates the potential suitability of the novel RTP as a sustained-release vehicle for ocular drug delivery for anti-neovascular therapies. Optimization of polymer chemistry for optimal drug loading and release is needed.

Hypotensive efficacy of topical brimonidine for intraocular pressure spikes following intravitreal injections of antivascular endothelial growth factor agents: a randomised crossover trial

PURPOSE

To determine the effect of topical brimonidine tartrate prophylaxis on intraocular pressure (IOP) spikes following intravitreal injection of antivascular endothelial growth factor (anti-VEGF) agents.

METHODS

This is a randomised crossover trial of consecutive non-glaucomatous eyes receiving intravitreal anti-VEGF injections between December 2016 and July 2017. All eyes were randomly assigned to no prophylaxis or topical brimonidine tartrate 0.15 % administered 20 min prior to injection in one of two consecutive visits. Measurements of IOP were obtained immediately (T0), 10 min (T10) and 20 min (T20) after injection during the visits with and without prophylaxis.

RESULTS

Among the 58 eyes of 55 patients (116 visits), the mean (SD) age was 74.3 (11.6), and 62% were female. The mean baseline IOP was 15.3 (2.3) mm Hg (range: 11-20). On average, the immediate postinjection IOP during the visit without prophylaxis was 41.6 (12) mm Hg (range: 17-81). Compared with no prophylaxis, the visit with preadministered topical brimonidine tartrate had a lower IOP at T0 (p<0.001), T10 (p=0.001) and T20 (p=0.043), and a smaller proportion of eyes with IOP elevation of greater than 20 mm Hg from preinjection (p=0.002) and IOP greater than 50 mm Hg at T0 (p=0.036). Without prophylaxis, two eyes (two patients) had an IOP of greater than 70 mm Hg at T0 and thus underwent anterior chamber paracentesis.

CONCLUSION

Topical brimonidine tartrate prophylaxis for intravitreal injection of anti-VEGF agents effectively reduces IOP spikes in non-glaucomatous eyes and may be easily incorporated into ophthalmologists' current practice.

TRIAL REGISTRATION NUMBER

NCT03513172.

The Effect of Anti-Vascular Endothelial Growth Factor Agents on Intraocular Pressure and Glaucoma: A Report by the American Academy of Ophthalmology

PURPOSE

To assess the effect of intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents on immediate and long-term intraocular pressure (IOP) elevation and glaucoma.

METHODS

Literature searches of the PubMed and Cochrane databases, last conducted in April 2018, yielded 253 unique citations. Of these, 41 met the inclusion criteria and were rated according to the strength of evidence. Two articles were rated level I, 17 were rated level II, and 15 were rated level III; an additional 7 were excluded because of poor study design and lack of relevance to the topic under evaluation.

RESULTS

The studies that reported on short-term IOP elevation (i.e., between 0 and 60 minutes) showed that an immediate increase in IOP is seen in all patients when measured between 0 and 30 minutes of intravitreal injection and that the IOP elevation decreases over time. The data on long-term IOP elevation were mixed; 7 studies reported that between 4% and 15% of patients developed sustained elevation of IOP at 9 to 24 months after injection, whereas 6 studies found no long-term change in IOP from 1 to 36 months after injection. Pretreatment with glaucoma medications, anterior chamber tap, vitreous reflux, longer intervals between injections, and longer axial lengths were associated with lower IOP elevations after injection. Data were mixed on the relationship between IOP increase and the type of intravitreal injection, number of intravitreal injections, preexisting glaucoma, and globe decompression before injection. There were no data on the onset or progression of glaucoma in the studies reviewed in this assessment.

CONCLUSIONS

Intravitreal injection of anti-VEGF agents results in an immediate and transient increase in IOP. A long-term increase in IOP also may be seen, and further studies are needed to determine at-risk populations. Although there is some suggestion in the literature, there is currently insufficient data to determine the impact of intravitreal anti-VEGF injections on glaucoma progression. Although pretreatment with glaucoma medications, performing anterior chamber paracentesis, or increasing the interval between injections may reduce the impact of transient IOP elevation, the clinical significance and associated risks of these interventions are unknown.

[Late and sustained intraocular pressure elevation related to intravitreal anti-VEGF injections: Cases requiring filtering surgery (French translation of the article)]

We report cases of delayed, sustained elevated intraocular pressure (IOP) associated with repeated intravitreal anti-VEGF injections (IVI), which ultimately resulted in the need for filtering surgery. Two of the three cases demonstrated severe IOP elevation despite maximal medical treatment following unilateral IVI and required urgent filtering surgery. Optic nerve involvement was severe in all three cases. These intravitreal injections were performed for exudative age-related macular degeneration (AMD), and the patients did not show any sign of glaucoma or ocular hypertension prior to the initiation of treatment. Elevated IOP secondary to intravitreal steroids is a well-known side effect, as is immediate transient IOP elevation associated with anti-VEGF injection. Late, sustained IOP elevation after repeated injections of anti-VEGF, described approximately ten years ago, is often underestimated. Its incidence is estimated between 2.1% and 13% according to studies and increases with the number of IVI (cumulative effect). The pathophysiologic process is becoming increasingly understood, and several risk factors for this chronic IOP elevation have been identified. Most often, it is a moderate IOP elevation for which topical monotherapy is sufficient, or sometimes two, three or four medications or even selective laser trabeculoplasty (SLT). However, filtering surgery may rarely be required. Our findings illustrate a little-described phenomenon: a sudden, severe, late IOP elevation in response to anti-VEGF by an "overflow" effect, requiring urgent filtering surgery.

Late and sustained intraocular pressure elevation related to intravitreal anti-VEGF injections: Cases requiring filtering surgery

We report cases of delayed, sustained elevated intraocular pressure (IOP) associated with repeated intravitreal anti-VEGF injections (IVI), which ultimately resulted in the need for filtering surgery. Two of the three cases demonstrated severe IOP elevation despite maximal medical treatment following unilateral IVI and required urgent filtering surgery. Optic nerve involvement was severe in all three cases. These intravitreal injections were performed for exudative age-related macular degeneration (AMD), and the patients did not show any sign of glaucoma or ocular hypertension prior to the initiation of treatment. Elevated IOP secondary to intravitreal steroids is a well-known side effect, as is immediate transient IOP elevation associated with anti-VEGF injection. Late, sustained IOP elevation after repeated injections of anti-VEGF, described approximately ten years ago, is often underestimated. Its incidence is estimated between 2.1 % and 13 % according to studies and increases with the number of IVI (cumulative effect). The pathophysiologic process is becoming increasingly understood, and several risk factors for this chronic IOP elevation have been identified. Most often, it is a moderate IOP elevation for which topical monotherapy is sufficient, or sometimes two, three or four medications or even selective laser trabeculoplasty (SLT). However, filtering surgery may rarely be required. Our findings illustrate a little-described phenomenon: a sudden, severe, late IOP elevation in response to anti-VEGF by an "overflow" effect, requiring urgent filtering surgery.

The acute and chronic effects of intravitreal anti-vascular endothelial growth factor injections on intraocular pressure: A review

The acute and chronic effects of repeated intravitreal antivascular endothelial growth factor (VEGF) injections on intraocular pressure have not been fully characterized, and the development of sustained ocular hypertension could adversely affect patients who are at risk of glaucomatous optic neuropathy. As expected, volume-driven, acute ocular hypertension immediately follows intravitreal injection, but this pressure elevation is generally transient and well tolerated. Several medications have been investigated to limit acute ocular hypertension following anti-VEGF therapy, but the benefits of pretreatment are not conclusive. Chronic, sustained ocular hypertension, distinct from the short-term acute ocular hypertension after each injection, has also been associated with repeated intravitreal anti-VEGF injections. Risk factors for chronic ocular hypertension include the total number of injections, a greater frequency of injection, and preexisting glaucoma. Proposed mechanisms for chronic ocular hypertension include microparticle obstruction, toxic or inflammatory effects on trabecular meshwork, as well as alterations in outflow facility by anti-VEGF agents. Although limiting anti-VEGF therapy could minimize the risk of both acute and chronic ocular hypertension, foregoing anti-VEGF therapy risks progression of various macular diseases with resulting permanent central vision loss. While definitive evidence of damage to the retinal nerve fiber layer is lacking, patients receiving repeated injections should be monitored for ocular hypertension and patients in whom sustained ocular hypertension subsequently developed should be periodically monitored for glaucomatous changes with optic nerve optical coherence tomography and static visual fields.

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Use of Anti-VEGF Agents in Glaucoma Surgery

A number of antivascular endothelial growth factor agents are currently available to treat various ocular conditions. These agents have similar, but distinct, biologic qualities and have been explored in the management of neovascular glaucoma and in glaucoma surgery. Several different delivery methods are described, and because these medications are routinely given as intraocular injections, some benefits over traditional antifibrotic medications when used in glaucoma surgery are noted. These agents effectively induce regression of anterior segment neovascularization and facilitate initial surgical management of neovascular glaucoma, but the long-term outcome of this condition remains dependent on definitive management of the underlying process. Use in trabeculectomy or tube shunt procedures for other types of glaucoma has shown promise in modulating bleb morphology but has not yet been found to be as effective as traditional antifibrotic agents. There are reports of persistently raised intraocular pressure after repeated use of the anti-VEGF agents, possibly related to frequency of injection. These medications have wide application in the field of surgical glaucoma, but a definitive role has yet to be defined.