In Vitro Effects of Antivascular Endothelial Growth Factors on Cultured Human Trabecular Meshwork Cells

Glaucoma: Novel antifibrotic therapeutics for the trabecular meshwork

Glaucoma is a chronic and progressive neurodegenerative disease characterized by the loss of retinal ganglion cells and visual field defects, and currently affects around 1% of the world's population. Elevated intraocular pressure (IOP) is the best-known modifiable risk factor and a key therapeutic target in hypertensive glaucoma. The trabecular meshwork (TM) is the main site of aqueous humor outflow resistance and therefore a critical regulator of IOP. Fibrosis, a reparative process characterized by the excessive deposition of extracellular matrix components and contractile myofibroblasts, can impair TM function and contribute to the pathogenesis of primary open-angle glaucoma (POAG) as well as the failure of minimally invasive glaucoma surgery (MIGS) devices. This paper provides a detailed overview of the current anti-fibrotic therapeutics targeting the TM in glaucoma, along with their anti-fibrotic mechanisms, efficacy as well as the current research progress from pre-clinical to clinical studies.

Effects of the Presence of Pseudoexfoliation on Intraocular Pressure and Retinal Nerve Fiber Layer Thickness in Patients with Macular Degeneration Receiving Intravitreal Ranibizumab

Aims: In the present study, we aimed to compare the effect of intravitreal ranibizumab (IVR) treatment on intraocular pressure (IOP) and retinal nerve fiber layer (RNFL) thickness in patients with age-related macular degeneration (AMD) with and without pseudoexfoliation (PEX). Materials and Methods: A total of 24 patients, 12 with PEX (12 eyes) and 12 without PEX (12 eyes), receiving IVR treatment for neovascular AMD between June 2017 and June 2019, were included in the study. Exclusion criteria were composed of the history of glaucoma, uveitis, intravitreal steroid administration, pars plana vitrectomy surgery, and less than three IVR injections. Such criteria as age, gender, follow-up times, number of injections administered, IOP, and RNFL thickness before the first injection and one month after the last injection were also recorded. Results: Age, gender, follow-up time, and the number of injections were similar in groups with and without PEX (p > 0.05). While mean post-treatment IOP values were not significantly higher in the PEX group (14.50 ± 3.06 vs. 12.91 ± 1.83 mmHg, p = 0.065), the values were significant for the non-PEX group (13.25 ± 2.76 vs. 11.83 ± 2.69 mmHg, p = 0.01), and these values were within normal IOP limits. Additionally, RNFL thickness was significantly thinner after treatment in both groups (91.41 ± 7.14 vs. 94.00 ± 6.76 in those with PEX; 95.58 ± 5.91 vs. 97.66 ± 6.89 in those without PEX; p < 0.05). The decrease in RNFL thickness in the PEX group was 2.58 ± 1.62 µ and in the non-PEX group was 2.08 ± 1.98 µ. However, there was no statistically significant difference between the two groups in terms of RNFL thinning (p = 0.505). Discussion: Ranibizumab may reduce RNFL thickness in patients with PEX. Longer-term studies including larger populations are necessary for understanding IOP and RNFL changes after anti-vascular endothelial growth factor (anti-VEGF) injection.

Intraocular Pressure-Related Events After Anti-Vascular Endothelial Growth Factor Therapy for Macular Edema Due to Central Retinal Vein Occlusion or Hemiretinal Vein Occlusion: SCORE2 Report 16 on a Secondary Analysis of a Randomized Clinical Trial

Importance

Intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections are used to treat a variety of posterior segment conditions, including some associated with glaucoma, such as macular edema due to central retinal vein occlusion (CRVO). Therefore, information regarding intraocular pressure (IOP)-related events associated with anti-VEGF therapies is important to help balance the risks and benefits over the course of therapy.

Objective

To investigate IOP-related events among participants in the Study of Comparative Treatments for Retinal Vein Occlusion 2 (SCORE2).

Design, Setting, and Participants

Secondary analysis of a randomized clinical trial that included 312 participants with macular edema secondary to CRVO or hemiretinal vein occlusion (HRVO) who were not taking IOP-lowering medications at baseline. First randomization occurred on September 14, 2014, and contained data through data freeze on April 1, 2020. Analysis took place from April 2020 through December 2020.

Interventions

Study participants were initially randomized to 6 monthly intravitreal injections of aflibercept or bevacizumab. At month 6, protocol-defined good responders were rerandomized to continued monthly or treat-and-extend dosing of their originally assigned study drug, and protocol-defined poor or marginal responders were switched to alternative treatment. After month 12, participants were treated as per investigator discretion.

Main Outcomes and Measures

Three different outcomes: (1) IOP elevation more than 10 mm Hg from baseline, (2) IOP to a level higher than 35 mm Hg, and (3) IOP-lowering incisional or laser surgery.

Results

Of the 312 participants meeting inclusion criteria (138 [44.2%] were female; mean [SD] age, 67.8 [12.1] years), 25 (8.0%) had IOP elevation more than 10 mm Hg over baseline through month 60, and 5 (1.6%) had IOP higher than 35 mm Hg. The 60-month Kaplan-Meier cumulative incidence of IOP elevation more than 10 mm Hg over baseline was 0.13 (95% CI, 0.08-0.19), and the 60-month Kaplan-Meier cumulative incidence of IOP higher than 35 mm Hg was 0.02 (95% CI, 0.01-0.06), and did not differ among participants initially randomly assigned to receive aflibercept or bevacizumab. Three participants (1.0%) underwent IOP-lowering incisional surgery, and 3 participants (1.0%) underwent IOP-lowering glaucoma laser surgery.

Conclusions and Relevance

Intravitreal anti-VEGF injections are used to treat some conditions associated with glaucoma, such as macular edema due to CRVO, and the rates of IOP-related events in this trial support monitoring IOP in eyes treated with anti-VEGF therapy for macular edema associated with CRVO or HRVO for up to 60 months.

Trial Registration

ClinicalTrials.gov Identifier: NCT01969708.

Ocular Therapeutics and Molecular Delivery Strategies for Neovascular Age-Related Macular Degeneration (nAMD)

Age-related macular degeneration (AMD) is the leading cause of vision loss in geriatric population. Intravitreal (IVT) injections are popular clinical option. Biologics and small molecules offer efficacy but relatively shorter half-life after intravitreal injections. To address these challenges, numerous technologies and therapies are under development. Most of these strategies aim to reduce the frequency of injections, thereby increasing patient compliance and reducing patient-associated burden. Unlike IVT frequent injections, molecular therapies such as cell therapy and gene therapy offer restoration ability hence gained a lot of traction. The recent approval of ocular gene therapy for inherited disease offers new hope in this direction. However, until such breakthrough therapies are available to the majority of patients, antibody therapeutics will be on the shelf, continuing to provide therapeutic benefits. The present review aims to highlight the status of pre-clinical and clinical studies of neovascular AMD treatment modalities including Anti-VEGF therapy, upcoming bispecific antibodies, small molecules, port delivery systems, photodynamic therapy, radiation therapy, gene therapy, cell therapy, and combination therapies.

Intraocular Pressure Variations After Intravitreal Injections Measured With an Implanted Suprachoroidal Telemetry Sensor

PURPOSE

Intravitreal injections (IVIs) may create transient intraocular pressure (IOP) elevation. This report describes continuous IOP fluctuations following multiple IVI measured with a permanent implantable sensor.

PATIENTS AND METHODS

We report the case of a 49-year-old white glaucomatous male with refractory macular edema secondary to central retinal vein occlusion in his left eye who underwent deep sclerectomy combined with the implantation of a suprachoroidal tonometry sensor. Serial IOP measurements were performed immediately before and after each IVI over a 1-year period.

RESULTS

During the first 7 months following deep sclerectomy, IOP remained below 10 mm Hg. During this period, mean IOP before each injection was 2.1±2.6 mm Hg, and each IVI caused a reduction of 1.2±0.8 mm Hg on average, with a maximum reduction of 2.7 mm Hg, before IOP normalized within 50 minutes to 24 hours. From 7 months postoperatively, mean IOP increased to the low teens. During this period, mean IOP before each injection was 9.9±1.8 mm Hg, and each IVI caused an increase of 15.8±11.7 mm Hg on average, with a maximum increase of 44.8 mm Hg, before IOP normalized within 20 minutes to 4 hours.

CONCLUSIONS

During the initial postoperative phase, IVI may cause acute reduction in IOP, either through subconjunctival leaks or increased filtration secondary to increased fluid pressure. Several months after surgery, this effect subsides and IOP spikes sharply immediately after each IVI, suggesting the resolution of the initial mechanism, most likely through scarring and fibrosis.

Effect of Anti-vascular Endothelial Growth Factor on the Matrix Metalloproteinase Activity in Trabecular Meshwork Cells

Purpose: To investigate the effects of anti-vascular endothelial growth factor (anti-VEGF) on the activity of matrix metalloproteinase (MMP) in human trabecular meshwork cells (HTMC). Methods: Primary HTMC cultures were exposed to 0, 0.25, and 0.50 mg/mL anti-VEGF bevacizumab (BV) for 24 hours. The permeability through the trabecular meshwork cell monolayer was assessed using carboxyfluorescein and trans-epithelial endothelial electrical resistance (TEER). The levels of MMP-1/-2 were measured by Western blotting and the production of nitric oxide (NO) was assessed with the Griess assay. Results: Bevacizumab at 0.50 mg/mL decreased the permeability of carboxyfluorescein significantly (p = 0.017) and did not affect TEER (p = 0.308). Administration of 0.50 mg/mL BV decreased MMP-1 and MMP-2 activities (p = 0.014, p = 0.016, respectively) and inhibited NO production significantly (p = 0.023). Conclusions: Anti-VEGF decreased the permeability through the HTMC monolayer, which was accompanied by decreased MMP-1/-2 activity and limited NO production.

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.

Issues with Intravitreal Administration of Anti-VEGF Drugs

Purpose

To provide an update of summary of risk factors and side effects of long-term use and contamination of intravitreal anti-VEGF injections.

Methods

We reviewed relevant publications of the topic of contamination of anti-VEGF injections and long-term side effects due to this reason.

Results

Due to the long-term use of anti-VEGF drugs and the higher number of injections worldwide, various studies have shown side effects in recent years, ranging from increased intraocular pressure to visual disturbing silicone oil vesicles in the vitreous cavity. Several studies have demonstrated that both the drug and the processing, storage, environmental factors and the material and design of the syringes have a decisive influence on these side effects.

Conclusion

The risks of deposits from syringes in the eye can be significantly reduced by various optimizations in transport, storage and syringe and cannula selection.

Intracameral bevacizumab role in trabeculectomy: A 1-year prospective randomized controlled study

Purpose:

To evaluate the effect of intracameral Bevacizumab on trabeculectomy success rates.

Methods:

A prospective, randomized, interventional clinical trial. Patients with primary open-angle glaucoma were randomly assigned to two groups: trabeculectomy with mitomycin C and trabeculectomy with mitomycin C and intracameral bevacizumab. Complete success is defined as an intraocular pressure (IOP) reduction of at least 30% from baseline IOP to a measured pressure of between 5 and 18 mm Hg without the use of IOP lowering medications. Qualified success is defined as same achievement of reduced IOP, but with the use of IOP lowering medications. Overall success is defined as same achievement of reduced IOP with or without the use of IOP lowering medications.

Results:

Thirty-three patients in the mitomycin C group and 36 patients in the mitomycin C and bevacizumab group were included in final analyses. The IOP at presentation was 28.3 ± 8 and 28.4 ± 8.6 mm Hg, compared to 10.8 ± 3.4 and 12.3 ± 3.7 mm Hg at 12 months (p < 0.0001) for the mitomycin C group and the mitomycin C and bevacizumab group, respectively. Complete success at 12 months was achieved in 65% of the mitomycin C group compared to 60% of the mitomycin C and bevacizumab group (p = 0.77). Overall success was achieved in 82% compared to 80% of patients at 12 months (p = 0.78). Both groups showed a statistically significant reduction in IOP after 6 and 12 months (p ⩽ 0.001). There were no statistically significant differences in visual acuity and complications.

Conclusion:

Intracameral bevacizumab during mitomycin C trabeculectomy in patients with primary open-angle glaucoma apparently does not improve success rates. The adjuvant use of intracameral bevacizumab is therefore not justified.

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.

Blocking VEGF by Bevacizumab Compromises Electrophysiological and Morphological Properties of Hippocampal Neurons

A hallmark of glioblastoma multiforme (GBM) is neoangiogenesis, mediated by the overexpression of vascular endothelial growth factor (VEGF). Anti-VEGF antibodies, like bevacizumab, prolong progression-free survival in GBM, however, this treatment has been reported to be associated with a decline in neurocognitive function. Therefore, this study focused on the effects of bevacizumab on neuronal function and plasticity. We analyzed neuronal membrane properties and synaptic plasticity in rat hippocampal slices, as well as spine dynamics in dissociated hippocampal neurons, to examine the impact of bevacizumab on hippocampal function and viability. VEGF inhibition resulted in profound impairments in hippocampal synaptic plasticity as well as reductions in dendritic spine number and length. Physiological properties of hippocampal neurons were also affected. These effects of VEGF blockade on hippocampal function may play a role in compromising memory and information processing and thus, may contribute to neurocognitive dysfunction in GBM patients treated with bevacizumab.

The Real-World Effect of Intravitreous Anti-Vascular Endothelial Growth Factor Drugs on Intraocular Pressure: An Analysis Using the IRIS Registry

PURPOSE

To identify sustained differences in intraocular pressure (IOP) after intravitreous injections of anti-vascular endothelial growth factor (VEGF) drugs.

DESIGN

Database study.

PARTICIPANTS

Patients seeing an ophthalmic provider who contributes to the database.

METHODS

We identified a total of 23 776 unique patients who received only a single type of anti-VEGF medication (bevacizumab, aflibercept, or ranibizumab) by injection in the right eye in the American Academy of Ophthalmology Intelligent Research in Sight Registry. Subgroups included patients with age-related macular degeneration only and patients who had not received an anti-VEGF injection for at least 1 year before the study. We examined those with at least 12, 18, and 25 injections for each of these 3 medications. For all groups, we used fellow, untreated eyes for comparison.

MAIN OUTCOME MEASURES

The mean change in IOP from baseline at a minimum of 1 year of follow-up and the proportion of eyes with a clinically significant IOP increase (defined as sustained rise of at least 6 mmHg to an IOP of more than 21 mmHg).

RESULTS

All patients in all groups receiving all drugs showed a decrease in IOP from baseline, with a mean of 0.9 mmHg in treated eyes compared with an average decrease of 0.2 mmHg in fellow untreated eyes, a statistically significant difference. A generalized linear model accounting for confounders associated bevacizumab with slightly less lowering of IOP than aflibercept and ranibizumab in most subgroups. A clinically significant IOP increase was seen in 2.6% of eyes receiving injections compared with 1.5% in the associated untreated fellow eyes. Clinically significant IOP increases occurred at a rate of 1.9%, 2.8%, and 2.8% for aflibercept, ranibizumab, and bevacizumab, respectively, which was significantly higher than untreated fellow eyes for bevacizumab and ranibizumab, but not for aflibercept.

CONCLUSIONS

These analyses from real-world data indicate that anti-VEGF intravitreous injections are associated with a small but statistically significant decrease in IOP over time. A proportion of patients, on average 2.6%, experienced a sustained clinically significant IOP rise with these drugs overall compared with 1.5% in the fellow untreated eyes. However, such an increase was not seen with aflibercept.

Concurrent injection of dexamethasone intravitreal implant and anti-angiogenic agent in patients with macular edema: A retrospective cohort study

To evaluate the safety and efficiency in macular edema patients who concurrently received a single injection of a dexamethasone intravitreal implant (DEX, 0.7 mg) and ranibizumab (2.3 mg).A retrospective cohort study was conducted, and medical records from 2012 to 2016 were reviewed. Patients who received concurrent DEX and ranibizumab injections with a follow-up period of at least 3 months were enrolled in the study group. An age and gender-matched group received ranibizumab injections and was designated the control group. The best-corrected visual acuity (BCVA), central macular thickness (CMT) and intraocular pressure (IOP) were included in the analysis. Steroid-induced ocular hypertension (SIOH) is defined as either an elevation of more than 10 mmHg from baseline or a single IOP measurement of more than 30 mmHg.A total of 26 patients were enrolled in the current study with 13 patients in each group. Both the BCVA (P = .04) and CMT (P < .01) achieved significant improvement after the follow-up period in the study group. The IOP increased after the injection but no significant elevation was observed throughout the follow-up period in the study group (P = .15). For SIOH, 1 patient in the study group had an elevated IOP of 10 mmHg (7.7%) at 2 postoperative months, and no single IOP measurement of more than 30 mmHg was obtained. Five patients (38.5%) in the study group received medical treatment that successfully retarded their IOP elevation, and no individuals required surgical management. In the control group, there were no significant fluctuations concerning BCVA, CMT, and IOP, and no ocular hypertension was observed. According to the inter-group analysis, the CMT and BCVA recovered more significantly in the study group than in the control group.Concurrent injection of DEX and ranibizumab is a preliminary method that shows effectiveness in treating ME. Furthermore, safety is also guaranteed, with moderate levels of severity and transient IOP elevation being observed. A future large-scale study is necessary to evaluate the long-term effects and safety of this combined treatment.

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.

Sustained intraocular pressure elevation in eyes treated with intravitreal injections of anti-vascular endothelial growth factor for diabetic macular edema in a real-life setting

PURPOSE

The aim of this study was to investigate the sustained intraocular pressure (IOP) elevation after repeated anti-VEGF intravitreal injections (IVI) in patients with diabetic macular edema (DME).

METHODS

A retrospective study included 140 eyes without prior glaucoma, treated with at least three anti-VEGF injections for DME between 2012 and 2016. IOP elevation was defined by an increase above baseline IOP by ≥6 mmHg. Baseline IOP was defined as the mean of IOP values before treatment initiation. Three groups were differentiated: group 1 without IOP elevation, groups 2 and 3 with IOP elevation and IOP <21 mmHg (group 2) and ≥21 mmHg (group 3). Rate and several risk factors of IOP elevation were assessed and compared between the three groups.

RESULTS

IOP elevation occurred in ten eyes (7.1%). IOP was <21 mmHg in six eyes and ≥21 mmHg in four eyes. Statistically significant associations were found between IOP elevation and the number of injections, and HbA1c level. Two patients required local hypotonic treatment.

CONCLUSIONS

In a real-life setting, we confirmed in eyes with center-involved DME without prior glaucoma or IOP elevation that repeated anti-VEGF IVI may increase the risk of sustained IOP elevation in about 7% of eyes.

VEGF as a Paracrine Regulator of Conventional Outflow Facility

Purpose

Vascular endothelial growth factor (VEGF) regulates microvascular endothelial permeability, and the permeability of Schlemm's canal (SC) endothelium influences conventional aqueous humor outflow. We hypothesize that VEGF signaling regulates outflow facility.

Methods

We measured outflow facility (C) in enucleated mouse eyes perfused with VEGF-A₁₆₄a, VEGF-A₁₆₅b, VEGF-D, or inhibitors to VEGF receptor 2 (VEGFR-2). We monitored VEGF-A secretion from human trabecular meshwork (TM) cells by ELISA after 24 hours of static culture or cyclic stretch. We used immunofluorescence microscopy to localize VEGF-A protein within the TM of mice.

Results

VEGF-A₁₆₄a increased C in enucleated mouse eyes. Cyclic stretch increased VEGF-A secretion by human TM cells, which corresponded to VEGF-A localization in the TM of mice. Blockade of VEGFR-2 decreased C, using either of the inhibitors SU5416 or Ki8751 or the inactive splice variant VEGF-A₁₆₅b. VEGF-D increased C, which could be blocked by Ki8751.

Conclusions

VEGF is a paracrine regulator of conventional outflow facility that is secreted by TM cells in response to mechanical stress. VEGF affects facility via VEGFR-2 likely at the level of SC endothelium. Disruption of VEGF signaling in the TM may explain why anti-VEGF therapy is associated with decreased outflow facility and sustained ocular hypertension.

Intravitreal Anti-VEGF Injections Reduce Aqueous Outflow Facility in Patients With Neovascular Age-Related Macular Degeneration

Purpose

We assess the effect of intravitreal anti-VEGF injections on tonographic outflow facility.

Methods

Patients with age-related macular degeneration who had received unilateral intravitreal anti-VEGF injections were recruited into two groups, those with ≤10 and those with ≥20 total anti-VEGF injections. Intraocular pressure and tonographic outflow facility of injected and uninjected fellow eyes were measured and compared between groups. Risk factors for development of reduced outflow facility also were assessed.

Results

Outflow facility was 12% lower in the injected eyes of patients who received ≥20 anti-VEGF injections, compared to contralateral uninjected eyes (P = 0.02). In contrast, there was no facility reduction for patients with ≤10 anti-VEGF injections (P = 0.4). In patients with ocular hypertension in the uninjected eye (IOP > 21 mm Hg, n = 5), the outflow facility of injected eyes was on average 46% lower (P = 0.01) than in the uninjected fellow eyes. This was significantly greater than the difference observed in patients with IOP ≤ 21 mm Hg in the uninjected eye (P = 2 × 10⁻⁴). In patients with ocular hypertension in the injected eye (n = 6) the differences in facility and IOP between contralateral eyes were significantly greater than in patients with IOP ≤ 21 mm Hg in the injected eye (P = 2 × 10⁻⁴ and P = 7 × 10⁻⁴, respectively).

Conclusions

Chronic anti-VEGF injections significantly reduce outflow facility in patients with AMD. The greatest facility reduction is observed in patients with baseline ocular hypertension. Ophthalmologists who administer anti-VEGF injections should be aware of these findings and monitor patients closely for changes in IOP or evidence of glaucoma, especially in those with pre-existing ocular hypertension.

Sustained Elevation of Intraocular Pressure Associated with Intravitreal Administration of Anti-vascular Endothelial Growth Factor: A Systematic Review and Meta-Analysis

This study aimed to assess whether repetitive intravitreal injections (IVI) of anti-vascular endothelial growth factor (anti-VEGF) cause sustained elevation of intraocular pressure (SE-IOP). We conducted a systematic review and meta-analysis based on five randomized controlled trials (RCTs) assessing 1428 subjects and 17 non-RCTs evaluating 8358 cases. In the RCTs, an increased risk of SE-IOP was found in the anti-VEGF group (summary risk ratio [RR] = 3.00, 95% confidence interval [CI]: 1.63–5.53) compared with the sham injection or laser group. The increased risk of SE-IOP was correlated with follow-up duration (RR = 2.14, 95% CI 0.69–6.57 at 6 months; RR = 3.15, 95% CI 0.99–10.09 at 12 months; RR = 3.48, 95% CI 1.38–8.78 at 23 months). The risk of SE-IOP after non-exclusion of pre-existing glaucoma patients (RR = 3.48, 95% CI 1.38–8.78) was higher than that obtained after excluding pre-existing glaucoma patients (RR = 2.6, 95% CI 1.16–5.81). In non-RCTs, the pooled prevalence of SE-IOP was 4.7% (95% CI 3.7–5.8) regardless of diagnosis criteria. In conclusion, repeated intravitreal injections of anti-VEGF agents cause a 2-fold elevation in SE-IOP risk.

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

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

Ocular Hypertension Following Intravitreal Antivascular Endothelial Growth Factor Therapy: Review of the Literature and Possible Role of Nitric Oxide

PURPOSE

To review the literature regarding ocular hypertension following intravitreal antivascular endothelial growth factor therapy, and to propose a novel mechanism for the development of ocular hypertension as a result of such therapy.

METHODS

The PubMed database was used to identify publications by using combinations of the search terms, "glaucoma," "ocular hypertension," "pegaptanib," "bevacizumab," "ranibizumab," "aflibercept," "anti-vascular endothelial growth factor," intraocular pressure," and "intravitreal." The reference lists of these publications were also reviewed for relevant articles.

RESULTS

Numerous articles have been published describing ocular hypertension, either immediate-term/short-term or delayed/sustained, following intravitreal antivascular endothelial growth factor therapy. Ocular hypertension has been reported following intravitreal pegaptanib, bevacizumab, and ranibizumab, and aflibercept. On the basis of the fact that vascular endothelial growth factor, normally present as a vascular modulating and reparative growth factor, is known to upregulate endothelial nitric oxide (NO) synthase, and that NO has been shown to decrease intraocular pressure in both normal and glaucomatous human and animal eyes, we propose a novel mechanism for sustained ocular hypertension following intravitreal antivascular endothelial growth factor therapy. We propose that such intravitreal therapy may lead to decreased NO in the anterior segment, which then leads to trabecular meshwork constriction, decreased outflow facility, and increased intraocular pressure.

CONCLUSIONS

Sustained ocular hypertension following the intravitreal administration of antivascular endothelial growth factor agents is a potentially serious side effect that has not been adequately explained. Further investigation is necessary to determine the role of NO in the mediation of this adverse effect.

Morphological Changes of Cortical and Hippocampal Neurons after Treatment with VEGF and Bevacizumab

Aims

Vascular endothelial growth factor (VEGF) is a hallmark of glioblastoma multiforme (GBM) and plays an important role in brain development and function. Recently, it has been reported that treatment of GBM patients with bevacizumab, an anti‐VEGF antibody, may cause a decline in neurocognitive function and compromise quality of life. Therefore, we investigated the effects of VEGF and bevacizumab on the morphology and on survival of neurons and glial cells.

Methods

Dissociated cortical and hippocampal cell cultures of juvenile rats were treated with VEGF, bevacizumab, and VEGF + bevacizumab. Neuronal and glial cell viability was analyzed, and the morphology of neurons was objectified by morphometric analysis.

Results

In cortical cultures, bevacizumab significantly decreased the number of neurons after 20 days and the number of glial cells subsequent 30 days. Additionally, an increase in the dendritic length of cortical neurons was obvious after 10 days of incubation with bevacizumab, but returned to control level after 30 days. In hippocampal cultures, cell viability was not affected by bevacizumab; however, dendritic length increased at day 10, but decreased after long‐term treatment.

Conclusion

Therefore, bevacizumab obviously has a cytotoxic effect in cortical cultures and decreases the dendritic length in hippocampal neurons after long‐term treatment.

Intraocular pressure trends after intravitreal injections of anti-vascular endothelial growth factor agents for diabetic macular edema

PURPOSE

To study intraocular pressure (IOP) trends and risk factors of IOP elevation after intravitreal anti-vascular endothelial growth factor injections in diabetic macular edema.

METHODS

A retrospective review of 760 eyes treated with intravitreal anti-vascular endothelial growth factor injections for diabetic macular edema was performed. The rate and risk factors of IOP elevation were assessed. Intraocular pressure elevation was defined as an increase above baseline IOP by ≥ 6 mmHg, increase above baseline by > 20%, or IOP elevation to > 24 mmHg on 2 or more consecutive visits after treatment. When more than one pretreatment IOP reading was available, baseline IOP was calculated as the mean of the available pretreatment IOP readings (up to a maximum of three last IOP readings). Intraocular pressure elevation was considered transient unless it was maintained throughout the follow-up or required treatment (persistent elevation).

RESULTS

Over a mean follow-up of 18 months, persistent and transient IOP elevation occurred in 44 (5.8%) and 53 (7%) eyes, respectively. The majority of eyes with persistent IOP elevation (70.4%) showed IOP elevation of > 20% from baseline. Only 13 eyes (1.71%) met the more strict criteria (> 6 mmHg from baseline or an IOP elevation > 24 mmHg). Final IOP was higher in the persistent IOP elevation group than the rest of the eyes (P < 0.001). Only the number of injections was associated with IOP elevation (P < 0.001).

CONCLUSION

Persistent IOP elevation after intravitreal anti-vascular endothelial growth factor injections for diabetic macular edema is uncommon but may be associated with a higher number of injections.

Predictors of sustained intraocular pressure elevation in eyes receiving intravitreal anti-vascular endothelial growth factor therapy

PURPOSE

To determine the intravitreal anti-vascular endothelial growth factor (VEGF) injection techniques and preferences within the retinal community and to identify potential factors associated with the development of sustained intraocular pressure (IOP) elevation in patients treated with intravitreal anti-VEGF therapy for neovascular age-related macular degeneration (AMD).

DESIGN

Cross-sectional physician survey.

METHODS

Five hundred and thirty retina specialists spanning both private and academic practices were surveyed regarding current anti-VEGF intravitreal injection protocols, including the anti-VEGF drug of choice, needle gauge, injection volume, injection technique, and self-reported prevalence of sustained IOP elevation. Multivariate logistic regressions were performed to assess the potential influence of these factors on long-term IOP.

RESULTS

Two hundred ninety-two specialists (55%) reported believing that intravitreal anti-VEGF therapy may cause sustained IOP elevation. Of these responses, the most common reported prevalence was 1%-2% (48%), followed by 3%-5% (34%). There was no relationship between the frequency of sustained IOP elevation and anti-VEGF drug of choice. Physicians who injected greater than 0.05 cc in less than 1 second were 5.56 times more likely to observe a high frequency of sustained IOP elevation (P=.006, 95% CI 1.64-18.89).

CONCLUSIONS

Based on physician survey data, serial anti-VEGF injections using higher injection volumes with a rapid injection technique may potentially lead to sustained IOP elevation. The underlying mechanism for this complication may be injury to the trabecular meshwork resulting from rapid elevations in IOP. Further investigation of the relationship between injection techniques and sustained IOP elevation in the form of retrospective or prospective clinical studies is warranted.

The link between intravitreal antivascular endothelial growth factor injections and glaucoma

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Morphological changes and viability of primary cultured human ocular trabecular meshwork cells after exposure to air

PURPOSE

To investigate the possible toxic effect of air exposure for an in vitro model of primary human ocular trabecular meshwork cells (HTM).

METHODS

HTM were isolated from five donor eyes and cultivated at 37 °C. After reaching confluence the cells were seeded on two well chamber slides. The chamber slides were turned upside down in a Petri culture dish full of culture medium and filled with air using a 5 ml syringe, starting this way the exposure of the cells to the air. Subsequently they were placed in the incubation chamber at 37 °C. Six groups of HTM cultures were set up: group 1 consisted of samples in which HTM were exposed to air for 30 min, group 2 for 1 h, group 3 for 3 h, group 4 for 6 h, group 5 for 12 h and group 6 for 24 h.

RESULTS

At 3 h after exposure, the morphology of the cells was still intact, at 6 h few cells appeared deformed and exhibited characteristics of more senescent cells. At 12 h after exposure to air the HTM cells started losing their typical morphology and appeared enlarged and compromised. Viability was superior to 94% in groups 1-3 while for groups 4, 5, 6 it was 82.7%, 39.5% and 12.7% respectively.

CONCLUSION

The toxic effect of air exposure for the studied in vitro model of HTM is not significant for the time period of one to three hours. However it starts reducing viability and alternating morphology 6 h after exposure until the time period of 24 h, where the percentage of living cells is drastically decreased. Therefore, we suggest that the use of an air bubble especially in glaucomatous patients should be applied with caution.

Local and systemic complications after intravitreal administration of anti-vascular endothelial growth factor agents in the treatment of different ocular diseases: a five-year retrospective study

PURPOSE

To observe the frequency of complications in patients undergoing intravitreal anti-VEGF injections for different ocular diseases in a five-year period.

MATERIALS AND METHODS

Charts of patients receiving intravitreal anti-VEGF were retrospectively reviewed. Out of 1173 eyes, 762 were treated with bevacizumab, 382 with ranibizumab, and 29 with pegaptanib. Data recorded included demographic information, clinical findings, total injections received, and info about the onset of adverse effects.

RESULTS

12.86% of the eyes treated with bevacizumab presented side-effects, while ratings in the ranibizumab and pegaptanib groups were 15.97% and 20.69%, respectively. Odds ratios calculated comparing incidences after each anti-VEGF are 0.78 (bevacizumab versus ranibizumab, p = 0.152), 0.57 (bevacizumab versus pegaptanib, p = 0.227), and 0.73 (ranibizumab versus pegaptanib, p = 0.508). A total of 185 complications were detected (62.16% after bevacizumab). Ocular side-effects registered were 40 cases of sustained intraocular pression (IOP) elevation, one infectious uveitis, one retinal detachment, and one sub-retinal hemorrhage. Other cases were related to transient IOP elevation immediately after injection. Systemic complications registered were one case of nausea, one episode of chest pain with acute vision loss, and one case of acute blood hypertension.

CONCLUSIONS

The majority of significant complications occurred in patients receiving multiple bevacizumab administrations. However, results may be affected by the difference in the utilization amount for each drug. AMD patients were the most represented, probably due to greater indication to treatment.

Recent advances in the management of neovascular glaucoma

The development of anti-vascular endothelial growth factor (VEGF) molecules has expanded the range of available treatment options for many ocular diseases, including neovascular glaucoma (NVG). A number of studies have explored the use of anti-VEGF agents as stand-alone or adjunctive treatment for NVG. Although no large, prospective, randomized trials have been performed to date, the growing body of knowledge suggests that anti-VEGF agents are effective at reversing iris and angle neovascularization and lowering intraocular pressure in patients with NVG. Response to a single injection is typically temporary; therefore, laser or incisional surgery is still necessary in most cases. Future research is needed to determine the optimal agent, dose, route of administration, and timing of treatment either as monotherapy or coupled with other medical and/or surgical interventions.

The effects of aflibercept on the viability and metabolism of ocular cells in vitro

PURPOSE

To investigate the effects of the vascular endothelial growth factor-neutralizing agent aflibercept on primary cultures of human trabecular meshwork cells (hTMC), human scleral fibroblasts (hFibro), and a retinal pigment epithelial cell line (ARPE-19).

METHODS

Various concentrations of aflibercept were incubated with confluent cell cultures for 24 hours. Ranibizumab was used as an active control for comparison. Assays of cellular metabolism (MTT assay) and cell viability (calcein dye uptake) were performed.

RESULTS

Compared with untreated controls (100% live), a 24-hour exposure to 1 mg/mL aflibercept had no significant effect on cell viability in hTMC (100.1 ± 1.7%), hFibro (102.4 ± 2.4%), or ARPE-19 (99.3 ± 3.9%) cells. Aflibercept vehicle controls also had no detrimental effect. Aflibercept (1 mg/mL) had no statistically significant effect on metabolic activity in hTMC (84.3 ± 10.2%), hFibro (102.7 ± 4.3%), and ARPE-19 (104.6 ± 12.6%) cells. When compared side-by-side in ARPE-19 cells, aflibercept and the anti-vascular endothelial growth factor agent ranibizumab had no toxicity at the highest concentration tested (1 mg/mL).

CONCLUSION

The authors' data reveal that concentrations of aflibercept in the range expected to occur in the human vitreous after intraocular injection are not harmful in an in vitro cell assay.

Intraocular Pressure rise after Anti-VEGF Treatment: Prevalence, Possible Mechanisms and Correlations

Intraocular pressure (IOP) rise after anti-vascular endothelial growth factor (VEGF) treatment for neovascular age-related macular degeneration (AMD) can be either short-term or long-term and may require medical intervention. Short-term IOP spikes are a fairly common and well recognized complication of anti-VEGF injections. Long-term IOP rise is less well-understood and disputed as a complication by some authors. We try to review current literature on the subject and especially studies focused on the prevalence of this complication, speculate on possible mechanisms of IOP rise and discuss correlations of long-term IOP rise with the nature of the injected agent, average number of injections, previous glaucoma history and other factors. How to cite this article: Kampougeris G, Spyropoulos D, Mitropoulou A. Intraocular Pressure rise after Anti-VEGF Treatment: Prevalence, Possible Mechanisms and Correlations. J Current Glau Prac 2013;7(1):19-24.

Effects of bevacizumab on neuronal viability of retinal ganglion cells in rats

The aim of this study was to investigate the effects of single and repeated intravitreal injections of bevacizumab on various retinal layers focusing more on retinal ganglion cells (RGCs) in healthy rats. Male Wistar rats were treated with intravitreal injection of bevacizimab (4 μL) within right eye. Left eyes were injected with the same volume of balanced salt solution (BSS) and used as control. Ten rats received a single intravitreal injection and ten rats had three injections, with seven days time interval. Histological and immunohistochemical evaluations and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay were performed in order to find out if some degree of apoptosis could occur on RGCs. Histological and immunohistochemical analyses showed that bevacizumab induces neuronal loss compared to control eyes, after multiple injections. RGCs apoptosis after multiple treatments was demonstrated to occur by TUNEL, Annexin V and Bax assays. The loss of ganglion cells following repeated injections was confirmed and quantified by the decrease in RGC specific protein Brn3a measured by western blotting in ten additional rats. The present results need to be considered when multiple intravitreal injection of bevacizumab are performed to treat retinal diseases.

The Anti-VEGF Epidemic: What are the Implications for Glaucoma Services?

The early reports on intraocular bevacizumab injections talked about a transient predictable probably volume-related rise in intraocular pressure (IOP). As the usage of the drug increased across the globe, sustained IOP elevation was noted. This article provides an insightly into the causes of IOP spikes and its impact on glaucoma practice.

Substratum compliance regulates human trabecular meshwork cell behaviors and response to latrunculin B

PURPOSE

To determine the impact of substratum compliance and latrunculin-B (Lat-B), both alone and together, on fundamental human trabecular meshwork (HTM) cell behavior. Lat-B is a reversible actin cytoskeleton disruptor that decreases resistance to aqueous humor outflow and decreases intraocular pressure.

METHODS

HTM cells were cultured on polyacrylamide hydrogels possessing values for compliance that mimic those reported for normal and glaucomatous HTM, or tissue culture plastic (TCP). Cells were treated with 0.2 μM or 2.0 μM Lat-B in dimethyl sulfoxide (DMSO) or DMSO alone. The impact of substratum compliance and/or Lat-B treatment on cell attachment, proliferation, surface area, aspect ratio, and migration were investigated.

RESULTS

HTM cells had profoundly decreased attachment and proliferation rates when cultured on hydrogels possessing compliance values that mimic those found for healthy HTM. The effect of Lat-B treatment on HTM cell surface area was less for cells cultured on more compliant hydrogels compared with TCP. HTM cell migration was increased on stiffer hydrogels that mimic the compliance of glaucomatous HTM and on TCP in comparison with more compliant hydrogels. Lat-B treatment decreased cellular migration on all surfaces for at least 7 hours after treatment.

CONCLUSIONS

Substratum compliance profoundly influenced HTM cell behaviors and modulated the response of HTM cells to Lat-B. The inclusion of substratum compliance that reflects healthy or glaucomatous HTM results in cell behaviors and responses to therapeutic agents in vitro that may more accurately reflect in vivo conditions.

Preclinical aspects of anti-VEGF agents for the treatment of wet AMD: ranibizumab and bevacizumab

Three anti-vascular endothelial growth factor (VEGF) therapies are currently used for the treatment of patients with wet age-related macular degeneration (AMD): pegaptanib, ranibizumab, and bevacizumab. Ranibizumab is an antibody fragment approved for the treatment of wet AMD. Bevacizumab is a full-length antibody registered for use in oncology but unlicensed for wet AMD. However, it is used off-label worldwide not only for wet AMD but also for various other ocular diseases associated with macular edema and abnormal vessel growth. We consider aspects of ranibizumab and bevacizumab in relation to their molecular characteristics, in vitro and in vivo properties, and preclinical safety data. Before 2009, most studies described the short-term toxicity of bevacizumab in multiple cell types of the eye. Since 2009, an increasing number of studies have compared the properties of ranibizumab and bevacizumab and investigated their impact on retinal cell functioning. Compared with bevacizumab, ranibizumab neutralizes VEGF better at low concentrations, maintains efficacy for longer, and has a higher retinal penetration and potency. Studies in animals demonstrate ranibizumab to be better localized to the injected eye, whereas bevacizumab appears to have a greater effect in the fellow eye. In humans, a localized and systemic effect has been reported for both molecules. In conclusion, overlapping yet distinct pharmacological properties of ranibizumab and bevacizumab indicate that safety or efficacy data from one cannot be extrapolated to the other.

Silicone oil microdroplets and protein aggregates in repackaged bevacizumab and ranibizumab: effects of long-term storage and product mishandling

PURPOSE

To quantify levels of subvisible particles and protein aggregates in repackaged bevacizumab obtained from compounding pharmacies, as well as in samples of bevacizumab and ranibizumab tested in controlled laboratory experiments.

METHODS

Repackaged bevacizumab was purchased from four external compounding pharmacies. For controlled laboratory studies, bevacizumab and placebo were drawn into plastic syringes and incubated at -20°C, 4°C, and room temperature (with and without exposure to light) for 12 weeks. In addition, mechanical shock occurring during shipping was mimicked with syringes containing bevacizumab. Particle counts and size distributions were quantified by particle characterization technology. Levels of monomer and soluble aggregates of bevacizumab were determined with size-exclusion high-performance liquid chromatography (SE-HPLC).

RESULTS

Repackaged bevacizumab from the compounding pharmacies had a wide range of particle counts (89,006 ± 56,406 to 602,062 ± 18,349/mL). Bevacizumab sampled directly from the original glass vial had particle counts of 63,839 ± 349/mL. There was up to a 10% monomer loss in the repackaged bevacizumab. Laboratory samples of repackaged bevacizumab and placebo had initial particle counts, respectively, of 283,675 ± 60,494/mL and 492,314 ± 389,361/mL. Freeze-thawing of both bevacizumab and placebo samples led to >1.2 million particles/mL. In all repackaged samples, most of the particles were due to silicone oil. SE-HPLC showed no significant differences for repackaged samples incubated in the laboratory under various conditions, compared with bevacizumab directly from vial. However, repeated freeze-thawing caused a more than 10% monomer loss.

CONCLUSIONS

Bevacizumab repackaged in plastic syringes could contain protein aggregates and is contaminated by silicone oil microdroplets. Freeze-thawing or other mishandling can further increase levels of particle contaminants.

Bleb morphology and vascularity after trabeculectomy with intravitreal ranibizumab: a pilot study

PURPOSE

To investigate outcomes after trabeculectomy using intraoperative intravitreal ranibizumab and topical mitomycin C (MMC) vs MMC alone.

DESIGN

Prospective randomized single-site pilot study.

METHODS

Patients diagnosed with primary open-angle glaucoma were randomized 1:1 to either combination intravitreal ranibizumab 0.5 mg and topically applied MMC (0.4 mg/mL for 2 min) or MMC (0.4 mg/mL for 2 min) therapy alone at time of trabeculectomy surgery. The primary endpoint measured was bleb morphology and vascularity using the Moorfields Bleb Grading System. Unqualified success was defined as postoperative intraocular pressure (IOP) of >5 and <22 mm Hg and a 30% decrease from baseline without use of postoperative hypotensive drops. Qualified success was defined as postoperative IOP of >5 and <22 mm Hg and a 30% decrease from baseline with use of postoperative hypotensive drops.

RESULTS

Ten patients were randomized to either standard trabeculectomy with MMC (Group A) or trabeculectomy with intravitreal ranibizumab and MMC (Group B). All patients completed the study and were classified as unqualified successes. There were statistically significant differences in peripheral bleb area (P = .02), peripheral bleb vascularity (P = .02), and non-bleb-related peripheral conjunctiva vascularity (P = .0003), with Group B exhibiting more diffuse blebs with a lower degree of vascularity.

CONCLUSIONS

Combination intravitreal ranibizumab and topical MMC at time of trabeculectomy resulted in more diffuse blebs with less vascularity when compared to use of topical MMC alone. Further studies are planned to better understand the utility of anti-vascular endothelial growth factor agents as modulators of wound healing post trabeculectomy.