Aqueous humor levels of vascular endothelial growth factor before and after intravitreal bevacizumab in type 3 versus type 1 and 2 neovascularization. A prospective, case-control study

Long-Term Impact of Diabetic Retinopathy on Response to Anti-VEGF Treatment in Neovascular AMD

Purpose

To explore the long-term effect of diabetic retinopathy on response to anti-vascular endothelial growth factor (VEGF) treatment in age-related macular degeneration-associated type 1 macular neovascularization (MNV) using optical coherence tomography angiography (OCTA).

Methods

A total of 45 eyes with exudative neovascular age-related macular degeneration (nAMD) with type 1 MNV were included in the analysis. Among them, 24 eyes of 24 patients had no history of diabetes mellitus (DM) in their anamnesis and were assigned to the Not Diabetic group; 21 eyes of 21 patients had mild diabetic retinopathy and were included in the Diabetic group. We considered the following outcome measures: (1) best-corrected visual acuity changes; (2) central macular thickness; (3) MNV lesion area; and (4) MNV flow area. The OCTA acquisitions were performed at the following time points: (1) baseline visit, which corresponded to the day before the first injection; (2) post-loading phase (LP), which was scheduled at 1 month after the last LP injection; and (3) 12-month follow-up visit.

Results

All morphofunctional parameters showed a significant improvement after the LP and at the 12-month follow-up visit. Specifically, both the Diabetic group and the Not Diabetic group displayed a significant reduction of MNV lesion areas at both the post-LP assessment (P = 0.026 and P = 0.016, respectively) and the 12-month follow-up (P = 0.039 and P = 0.025, respectively). Similarly, the MNV flow area was significantly decreased in both the Diabetic group and the Not Diabetic group at the post-LP assessment (P < 0.001 and P = 0.012, respectively) and at the 12-month follow-up (P = 0.01 and P = 0.035, respectively) compared to baseline. A smaller reduction in the MNV lesion area was observed in the Diabetic group at both the post-LP evaluation (P = 0.015) and the 12-month follow-up (P = 0.032). No other significant differences were found between the groups for the other parameters (P > 0.05).

Conclusions

Our results indicated that the Diabetic group exhibited a smaller reduction in MNV lesion area after 12 months of anti-VEGF treatment. This highlights the importance of considering diabetic retinopathy as a potential modifier of treatment outcomes in nAMD management, with DM serving as a crucial risk factor during anti-angiogenic treatment.

Current Perspectives on Type 3 Macular Neovascularization due to Age-Related Macular Degeneration

BACKGROUND

The aim of this review was to systematically summarize the current knowledge on type 3 macular neovascularization (MNV3) in age-related macular degeneration (AMD).

SUMMARY

Recent histopathologic and multimodal imaging findings led to the consensus definition of the new term "type 3 macular neovascularization" in AMD. MNV3 originates in the deep vascular plexus as a neovascular process without connection with the retinal pigment epithelium in the initial stages. This type has numerous clinical and pathomorphologic features that separate it from the other two types of MNV in AMD. Besides, its frequency appears to be higher than previously thought. In optical coherence tomography (OCT), MNV3 can be classified into stages 1-3. Hyperreflective foci in the outer retina possibly represent a precursor lesion. In addition, MNV3 is characterized by a strong association with reticular pseudodrusen, a high rate of bilaterality, close associations with advanced age and arterial hypertension, decreased choroidal thickness, and decreased choriocapillaris flow signals. Data from latest anti-vascular endothelial growth factor studies in MNV3 suggest that the OCT biomarkers in intraretinal and subretinal fluids should be interpreted differently than in the other types. Additionally, data from MNV3 eyes should be analyzed separately, allowing optimal type-specific treatment strategies in the future.

KEY MESSAGES

This review highlights the need for accurate characterization of neovascular AMD lesions and an MNV type-specific approach, particularly for MNV3.

Pushing Retinal Imaging Forward: Innovations and Their Clinical Meaning - The 2022 Ophthalmologica Lecture

Retinal imaging has greatly expanded our understanding of various pathological conditions. This article presents a summary of the key points covered during the 2022 Ophthalmologica Lecture held at the Euretina Congress in Hamburg. The first part of the article focuses on the use of optical coherence tomography angiography to examine and comprehend the choroid in age-related macular degeneration (AMD). Subsequently, we delve into the discussion of the "postreceptor neuronal loss" theory in AMD, which was studied using en face structural optical coherence tomography (OCT). Following that, we explore pertinent findings obtained through cross-sectional OCT in retinal and optic nerve diseases, such as AMD, diabetic macular edema, pathologic myopia, central serous chorioretinopathy, and Leber's hereditary optic neuropathy.

Assessment of choriocapillaris/Sattler and Haller layer changes after intravitreal injection in eyes with neovascular age-related macular degeneration: aflibercept vs ranibizumab

PURPOSE

To evaluate the changes in choriocapillaris (CC)/Sattler and Haller layer thicknesses in eyes with neovascular age-related macular degeneration (nAMD) after aflibercept or ranibizumab injections.

STUDY DESIGN

Retrospective.

METHODS

A total of 70 eyes of 70 patients with treatment-naïve exudative nAMD were treated with 3 consecutive injections of aflibercept (IVA) or ranibizumab (IVR). CC/Sattler and Haller layer thicknesses were measured at the nasal and temporal regions 1000 µm from the center of the fovea by enhanced-depth imaging optical coherence tomography at baseline and after the 3 monthly intravitreal injections. In addition, the hyperfluorescence region (HF) was measured as the largest horizontal diameter of the hyperfluorescence area on the early-middle phase fluorescein angiographic images at baseline and after the 3 loading doses.

RESULTS

After the 3 consecutive injections, the mean reductions in the nasal/temporal CC/Sattler layer thicknesses in the IVR and IVA groups were  - 10.1 ± 2.3/ - 8.5 ± 1.8 and  - 25.2 ± 15.2/ - 19.4 ± 12.8 μm, respectively. Also, the mean reductions in the nasal/temporal Haller layer thicknesses in the IVR and IVA groups were  - 6.5 ± 3.6/ - 7.2 ± 7.9 and  - 9.5 ± 8.0/ - 7.0 ± 6.2 μm, respectively. The changes in the CC/Sattler layer thicknesses of the IVA group were greater than those of the IVR group (P < .001); however, the changes in the Haller layer thickness were similar between the groups (P > .05). The mean decrease in the HF size of the IVA group was greater than that of the IVR group (P < .001).

CONCLUSIONS

Aflibercept treatment has a more pronounced effect on the CC/Sattler layer. Such results may indicate that aflibercept treatment influences choroidal neovascularization, possibly by reducing the capillary permeability associated with active neovascularization in the CC layer.

The RAP study, report 4: morphological and topographical characteristics of multifocal macular neovascularization type 3

PURPOSE

To report on the morphological characteristics and regional distribution of multifocal macular neovascularization type 3 (mMNV3).

METHODS

Twenty-two consecutive eyes of 21 patients with mMNV3 were included using multimodal imaging. The count and stage of lesions of all MNV types and the existence of exudate and hemorrhage were determined. Also, we addressed the regional distribution of MNV3 lesions between the superior-inferior and the nasal-temporal halves of the macula, and the range of the distance of the lesions from the central fovea. Furthermore, we explored the number of feeding vessels including the cilioretinal artery.

RESULTS

We found 51 lesions in 22 eyes of 21 patients. They were bifocal in 16 (73%) eyes, trifocal in 5 (23%), and quadrifocal in one (4%). No lesion of MNV1 or 2 was found. Fifteen (68%), 2 (9%), and 16 (73%) eyes were associated with retinal hard exudate, subretinal pigment epithelium exudate, and intraretinal hemorrhage, respectively. Thirty (59%) lesions were located in the temporal half of the macula, whereas 21 (41%) were located nasally (p = 0.07). One (2%) lesion was closer than 500 µm, 49 (96%) between 500 and 1500 µm, and one (2%) between 1500 and 3000 µm. The lesions were supplied by one arteriole in one (4%) eye, two arterioles in 16 (73%) eyes, and 3 arterioles in 5 (23%) eyes. The CRA contributed as a feeding vessel in 5 (23%) eyes.

CONCLUSION

The multifocal variant of MNV3 has specific morphological and topographical characteristics. Multimodal imaging allows the understanding of the pathomorphological condition in more detail.

THE RAP STUDY, REPORT TWO: The Regional Distribution of Macular Neovascularization Type 3, a Novel Insight Into Its Etiology

PURPOSE

To explore the regional distribution of macular neovascularization type 3 (MNV3).

METHODS

Seventy-eight eyes of 78 patients were reviewed. We defined the location of each lesion after applying a modified ETDRS grid and the incidence of simultaneous MNV1 or 2. Also, we investigated the distribution of MNV3 at the outline of the foveal avascular zone and when the diameter of foveal avascular zone was less than 325 µm.

RESULTS

The distribution of MNV3 was 4 lesions (5%) from the center to 500 µm, 72 (92%) from 500 µm to 1500 µm, and 2 (3%) from 1,500 µm to 3000 µm. The distribution in respect of the ETDRS fields was 7 (9%) nasal, 16 (20%) superior, 32 (40%) temporal, and 23 (31%) inferior. No additional MNV1 or 2 were found elsewhere. Most lesions tended to distribute along straight bands radiating from the perifoveal area, mainly in the temporal half (72%). None of the cases had MNV3 at the boundary of the foveal avascular zone. Only five cases had foveal avascular zone diameter of less than 325 µm, the closest lesion was 425 µm away from the center.

CONCLUSION

MNV3 lesions are most likely neither symmetrical nor uniformly distributed. They have a higher affinity to distribute radially in the temporal perifoveal area.

Changes in aqueous and vitreous inflammatory cytokine levels in neovascular age-related macular degeneration: a systematic review and meta-analysis

Inflammatory cytokines are involved in the pathogenesis of neovascular age-related macular degeneration (nAMD) and have been shown to be useful as diagnostic and predictive biomarkers. Given the heterogeneity of data within the literature, we aimed to quantitatively summarize data related to inflammatory cytokines in nAMD. A systematic search without year limitation was performed up to 13 April 2020. Studies were included if they provided data on aqueous or vitreous cytokine concentrations in patients with nAMD. Data were extracted from 95 studies that encompassed 3105 study eyes with nAMD and 1209 control eyes. Effect sizes were generated as standardized mean differences (SMDs) of cytokine concentrations between patients with nAMD and controls. Among the 4314 eyes in 95 studies, aqueous concentrations (standard mean difference, 95% confidence interval and p-value) of MCP-1 (0.43, 0.09 to 0.77 and p = 0.01), MIG (0.63, 0.31 to 0.94 and p = 0.0001), TGF-β (0.45, 0.07 to 0.82 and p = 0.02) and VEGF (0.64, 0.31 to 0.98 and p = 0.0001) were significantly higher in patients with nAMD compared to healthy controls. No differences, failed sensitivity analyses or insufficient data were found between patients with nAMD and healthy controls for the concentrations of the remaining cytokines and with all vitreous samples. Previous studies had shown conflicting associations with nAMD for all 27 cytokines assessed. Our analysis indicates multiple candidate cytokines other than VEGF that are implicated in nAMD and adds clarity to the previous literature. This will help focus translational research in nAMD investigating biomarkers and therapeutic targets.

Multimodal Imaging to Detect in vivo Responses to Aflibercept Therapy in a Mouse Model of Type 3 Neovascularization

PURPOSE

The aim of this study was to characterize the response to aflibercept in a mouse model of type 3 neovascularization, the neoretinal vascularization (NRV) 2 mouse line.

METHODS

Twelve NRV2 mice were assigned to one of the following groups: (1) 6 mice were injected with aflibercept 3 µg/g at postnatal day (P) 15 ("aflibercept" group), and (2) the remaining 6 mice did not receive any treatment ("placebo" group). The mice were examined at P30 and P44.

RESULTS

The NRV mice's retinas were characterized by regions of depigmentation that were topographically associated with hyperfluorescent lesions seen on fluorescein angiography (FA) images. On optical coherence tomography images, intraretinal neovascularizations were visualized as hyperreflective lesions mainly localized within the outer plexiform and outer nuclear layers. The average number of intraretinal neovascular lesions visualized on FA at P30 was 5.0 ± 2.2 in the aflibercept group and 20.7 ± 2.4 in the placebo group (p < 0.0001). At P44, the average number of intraretinal lesions was still lower in the aflibercept group, although this difference was not statistically significant (p = 0.088).

CONCLUSION

Aflibercept therapy was effective in inhibiting pathologic angiogenesis in the NRV2 mouse model. However, the successive treatment washout resulted in an increase in the number of lesions.

Evaluation of the inner choroid using OCT angiography

The advent of optical coherence tomography angiography (OCTA) has allowed a qualitative and quantitative analysis of the retinal vasculature and the choriocapillaris. With the use of OCTA, several studies evaluated the changes in the choriocapillaris showing how this vascular structure plays a significant role in the pathogenesis of different conditions. This article reviews the current methods of analysis of the choriocapillaris and the relevant findings in different chorioretinal diseases.

INTRAVITREAL ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR FOR THE MANAGEMENT OF NEOVASCULARIZATION IN RETINOBLASTOMA AFTER INTRAVENOUS AND/OR INTRAARTERIAL CHEMOTHERAPY: Long-Term Outcomes in a Series of 35 Eyes

PURPOSE

To report the use of anti-vascular endothelial growth factor in the management of retinoblastoma.

METHODS

Retrospective review of 35 eyes (33 patients) treated with at least one intravitreal anti-vascular endothelial growth factor (ranibizumab and/or aflibercept) for new iris (n = 26) and/or retinal neovascularization (n = 21) after intravenous chemotherapy and/or intraarterial chemotherapy.

RESULTS

Most eyes (n = 31/35, 89%) were Group D or E. Previous treatments were salvage intraarterial chemotherapy after intravenous chemotherapy (n = 21/35, 60%), first-line intraarterial chemotherapy (n = 7/35, 20%), and first-line intravenous chemotherapy (n = 7/35, 20%). Associated clinical features were retinal ischemia (94%), retinal detachment (51%), active tumor (34%), intravitreal hemorrhage (43%), and/or glaucoma (17%). Mean 1.6 anti-vascular endothelial growth factor injections/eye were given; 28 eyes received ranibizumab, 2 aflibercept, and 5 both agents. Eight eyes underwent complementary treatments of ischemic retina. Resolution of neovascularization was observed in 28 eyes (n = 28/35, 80%). Globe salvage was achieved in 51% (n = 18/35), including 25% of those with active tumor (n = 3/12). One eye became phthisic. Sixteen eyes were enucleated, nine for tumor relapse/progression. Five eyes had high-risk histopathologic risk factors and received adjuvant intravenous chemotherapy. All patients are alive with no extraocular extension nor metastases (mean follow-up 3.7 years, range 1.1-7.6).

CONCLUSION

Intravitreal anti-vascular endothelial growth factor contributed to a globe salvage rate of 51% by providing conditions to continue conservative treatment.

Anterior chamber paracentesis during intravitreal injections in observational trials: effectiveness and safety and effects

A paracentesis prior to an intravitreal injection is a very safe procedure and can prevent IOP-spikes after injections. As these spikes pose the risk of inducing glaucomatous changes particularly in patients with frequent injections and/or with a risk profile, a regular paracentesis prior to an injection may be considered and discussed with the patient.

Distinct Aqueous Humour Cytokine Profiles of Patients with Pachychoroid Neovasculopathy and Neovascular Age-related Macular Degeneration

This study investigated the pathophysiological features of pachychoroid neovasculopathy (PNV) and neovascular age-related macular degeneration (nAMD) by analysing and comparing cytokine profiles in aqueous humour (AH) collected from 18 PNV, 18 nAMD and 11 control patients. Responses to intravitreal injection of aflibercept were also analysed in the PNV and nAMD groups. In the PNV group, vascular endothelial growth factor (VEGF)-A was significantly lower than in the nAMD group (p = 0.03) but was almost identical to that in the control group (p = 0.86). The nAMD group showed positive correlations between interleukin (IL)-6 and IL-8 (r = 0.78, p < 0.001), IL-6 and monocyte chemoattractant protein (MCP)-1 (r = 0.68, p = 0.002) and IL-8 and MCP-1 (r = 0.68, p = 0.002). In the nAMD group, eyes with dry maculae one month after the first aflibercept injection showed significantly lower VEGF-A and placental growth factor (PlGF) at baseline than those with wet maculae (p = 0.02 for both). However, there was no significant difference between dry and wet maculae in the PNV group. The results suggest that angiogenic factors and proinflammatory cytokines may play the distinct roles in the pathogenesis of PNV and nAMD.

Systemic and ocular fluid compounds as potential biomarkers in age-related macular degeneration

Biomarkers can help unravel mechanisms of disease and identify new targets for therapy. They can also be useful in clinical practice for monitoring disease progression, evaluation of treatment efficacy, and risk assessment in multifactorial diseases, such as age-related macular degeneration (AMD). AMD is a highly prevalent progressive retinal disorder for which multiple genetic and environmental risk factors have been described, but the exact etiology is not yet fully understood. Many compounds have been evaluated for their association with AMD. We performed an extensive literature review of all compounds measured in serum, plasma, vitreous, aqueous humor, and urine of AMD patients. Over 3600 articles were screened, resulting in more than 100 different compounds analyzed in AMD studies, involved in neovascularization, immunity, lipid metabolism, extracellular matrix, oxidative stress, diet, hormones, and comorbidities (such as kidney disease). For each compound, we provide a short description of its function and discuss the results of the studies in relation to its usefulness as AMD biomarker. In addition, biomarkers identified by hypothesis-free techniques, including metabolomics, proteomics, and epigenomics, are covered. In summary, compounds belonging to the oxidative stress pathway, the complement system, and lipid metabolism are the most promising biomarker candidates for AMD. We hope that this comprehensive survey of the literature on systemic and ocular fluid compounds as potential biomarkers in AMD will provide a stepping stone for future research and possible implementation in clinical practice.

Aqueous vascular endothelial growth factor and clinical outcomes correlation after single intravitreal injection of bevacizumab in patients with neovascular age-related macular degeneration

Purpose

To evaluate the concentration of vascular endothelial growth factor (VEGF) in aqueous humor after a single intravitreal injection of bevacizumab (IVB) in eyes with neovascular age-related macular degeneration (AMD).

Methods

In this prospective interventional case series study, 24 eyes of 24 patients with types 1 and 2 choroidal neovascularization secondary to neovascular AMD were treated with a single intravitreal injection of bevacizumab. Aqueous humor samples were obtained before the intravitreal injection and at one week, one month, and three months follow-up periods. Best-corrected visual acuity (BCVA) and three spectral-domain optical coherence tomography parameters (central retinal thickness, macular volume and macular area) were also analyzed and correlated with VEGF expression at the baseline and each follow-up period.

Results

All of the ninety-six aqueous humor study taps were well tolerated by the study patients without adverse events. Increased VEGF levels (mean ± SD = 179.7 ± 88.3 pg/mL) were observed in the aqueous humor of all study patients before the intravitreal injection of bevacizumab. At all follow-up periods, compared to baseline, levels of VEGF significantly reduced (P < 0.0001), and BCVA significantly improved (P < 0.005). The lowest VEGF expression was observed at 1 week, and the greatest BCVA improvement occurred 1 month after treatment. At 1 month, central retinal thickness (CRT), macular volume (MV), and macular area (MA) significantly reduced compared to baseline (P < 0.0001, P = 0.0005, P = 0.007, P = 0.009, respectively). At 1 week and 3 months, although without statistical significance (P > 0.005), CRT, MV and MA also reduced in comparison to baseline.

Conclusions

Single intravitreal bevacizumab injection in eyes with neovascular AMD resulted in a substantial decrease of aqueous VEGF levels 1 week after treatment with the greatest improvement of clinical outcomes occurring at 1 month follow-up.

Elevated angiopoietin 2 in aqueous of patients with neovascular age related macular degeneration correlates with disease severity at presentation

Angiopoietin 2 (ANG2) is a proangiogenic cytokine which may have an implication in neovascular age related macular degeneration (nAMD). In 24 eyes of 24 subjects presenting with treatment naïve nAMD and 26 eyes of 26 control patients, aqueous humor samples were collected at the time of intervention (intravitreal injection of anti-vascular endothelial growth factor or cataract extraction). Best corrected visual acuity (BCVA) with and central macular thickness (CMT) using optical coherence tomography (OCT) were measured before each injection in the nAMD group. Aqueous cytokine levels were determined by immunoassay using a multiplex array (Quansys Biosciences, Logan, UT). Levels of ANG2 in the aqueous were significantly higher in nAMD patients than those of the control group (p < 0.0001), so were hepatocyte growth factor (HGF), interleukin-8 (IL-8) and tissue inhibitor of metalloproteinase 1 (TIMP 1), all with p < 0.001. ANG2 correlated with worse BCVA (r = 0.44, p-value = 0.027) and greater CMT (r = 0.66, p-value < 0.0001) on optical coherence tomography (OCT). ANG2 is upregulated in patients with nAMD and correlates with severity of disease at presentation.

Detection of aqueous VEGF concentrations before and after intravitreal injection of anti-VEGF antibody using low-volume sampling paper-based ELISA

Intraocular vascular endothelial growth factor (VEGF) levels play an important role in the pathogenesis of blindness-related diseases, such as age-related macular degeneration (AMD). Here, we aimed to develop a paper-based enzyme-linked immunosorbent assay (P-ELISA) to analyze the suppression of aqueous VEGF concentrations following intravitreal injection (IVI) of anti-VEGF antibody (bevacizumab or ranibizumab). A total of 25 eyes with wet AMD, one with myopic neovascularization, and one with polypoidal choroidal vasculopathy were enrolled in this study. The limit of detection using P-ELISA was 0.03 pg/mL. Forty-six consecutive samples of aqueous humor were acquired. From all samples, 66.67% (10/15) achieved complete VEGF suppression (below the detection limit) within 5 weeks of receiving IVI of anti-VEGF antibody. Only 13.33% of samples (2/15) achieved complete VEGF suppression 5 weeks after receiving treatment. In some patients, elevated VEGF was still detected 5 weeks after receipt of anti-VEGF antibody, and all samples (10/10) were found to have elevated VEGF levels 49 days after treatment. Thus, we suggest that monthly IVI of anti-VEGF antibody may be required to ensure durable VEGF inhibition. Ultrasensitive P-ELISA can detect elevated VEGF at an earlier time point and may facilitate decision-making regarding appropriate treatment strategies.

Comparison of intravitreal aflibercept and ranibizumab injections on subfoveal and peripapillary choroidal thickness in eyes with neovascular age-related macular degeneration

PURPOSE

We aimed to compare changes in subfoveal and peripapillary choroidal thickness (CT) after intravitreal aflibercept or ranibizumab injections for neovascular age-related macular degeneration (AMD).

METHODS

Medical records of 54 treatment-naïve, consecutive patients (54 eyes) who were diagnosed with neovascular AMD and received three monthly injections of aflibercept (21 eyes) or ranibizumab (33 eyes) were reviewed. Subfoveal and peripapillary CT were measured with images obtained using spectral domain optical coherence tomography at baseline and at three months.

RESULTS

Subfoveal CT decreased from 232.2 ± 94.4 μm at baseline to 207.1 ± 89.3 μm at three months in the aflibercept group (p < 0.001) and from 231.5 ± 102.9 μm to 220.0 ± 98.0 μm in the ranibizumab group (p = 0.006). The reduction was greater in the aflibercept group than in the ranibizumab group (p = 0.024). Peripapillary CT decreased from 157.2 ± 62.2 μm at baseline to 147.4 ± 62.2 μm at three months in the aflibercept group (p < 0.001). However, the change in peripapillary CT from 154.9 ± 46.5 μm at baseline to 152.3 ± 50.0 μm at three months was not significant in the ranibizumab group (p = 0.123).

CONCLUSIONS

Intravitreally injected aflibercept significantly decreased subfoveal CT more than ranibizumab. Choroidal thinning after aflibercept injection was not limited to the subfoveal area, but extended beyond the macula as well.

Geographic atrophy in patients receiving anti-vascular endothelial growth factor for neovascular age-related macular degeneration

PURPOSE

To examine factors associated with the apparent growth of geographic atrophy (GA) in a consecutive series of eyes with treatment-naive neovascular age-related macular degeneration receiving intravitreal anti-vascular endothelial growth factor therapy on a treat-and-extend regimen.

METHODS

This was a retrospective cohort study. Two independent graders identified areas of GA using near-infrared reflectance imaging and spectral domain optical coherence tomography (SD-OCT). Neovascular lesion subtypes were classified based on fluorescein angiography (FA) as occult choroidal neovascularization, classic choroidal neovascularization, retinal angiomatous proliferation, or mixed choroidal neovascularization, and by the anatomical classification system which utilizes FA and SD-OCT as Types 1 (sub-retinal pigment epithelium), 2 (subretinal), 3 (intraretinal), or mixed neovascularization.

RESULTS

Ninety-one patients (94 eyes) fit the inclusion criteria, of which 52 eyes (55.3%) experienced apparent GA growth. The odds of developing apparent GA were significantly lower in Type 1 neovascularization compared to the other lesion types (P < 0.001). Using both FA and SD-OCT to classify neovascular age-related macular degeneration significantly improves the goodness of fit in the correlation between apparent GA growth and baseline neovascular lesion type (P < 0.001).

CONCLUSION

Treatment-naive neovascular age-related macular degeneration eyes with Type 1 neovascularization at baseline were less likely to develop GA than eyes with other types. The correlation between apparent GA growth and subtype of neovascularization is stronger when lesions are classified with an anatomic grading that utilizes both FA and SD-OCT.

Profile of intraocular immune mediators in patients with age-related macular degeneration and the effect of intravitreal bevacizumab injection

PURPOSE

To measure intraocular cytokine levels in patients with exudative age-related macular degeneration and analyze changes in the cytokine profile 2 days after intravitreal bevacizumab injection.

METHODS

This prospective case-control study enrolled 37 patients (37 eyes) with age-related macular degeneration including polypoidal choroidal vasculopathy. Twenty-eight age-matched patients (28 eyes) who underwent cataract surgery were used as controls. Undiluted aqueous humor samples were collected after intravitreal bevacizumab injection. Two days after intravitreal bevacizumab injection, cataract surgery was performed and undiluted aqueous humor samples were collected at the beginning of surgery (10 eyes). Twenty-three cytokines were measured using flow cytometry. P values were corrected in multiple comparisons using the conservative Bonferroni-Holm method. The level of significance was set at 0.0022 (0.05/23).

RESULTS

At baseline, aqueous humor levels of vascular endothelial growth factor, angiogenin, interferon gamma-inducible protein (IP)-10, macrophage inflammatory protein (MIP)-1β, monokine induced by interferon γ (Mig), and monocyte chemotactic protein (MCP)-1 were significantly higher in the age-related macular degeneration group than in the control group (P < 0.0022). The result of exploratory multivariate analysis showed that elevated angiogenin level was an important factor that discriminates the two groups (P = 0.0004). Two days after intravitreal bevacizumab injection, vascular endothelial growth factor levels tended to be reduced (P = 0.049), whereas interleukin (IL)-6 and IL-8 levels increased significantly (P < 0.0022).

CONCLUSION

Vascular endothelial growth factor and also angiogenin, IP-10, MCP-1, MIP-1β, and Mig may be related to the pathogenesis of age-related macular degeneration. Intravitreal bevacizumab injection increases inflammatory cytokine levels, suggesting the induction of an inflammatory process.

The incidence of neovascular subtypes in newly diagnosed neovascular age-related macular degeneration

PURPOSE

To determine the frequency of neovascularization subtypes as determined by fluorescein angiography (FA) alone vs FA and optical coherence tomography (OCT) grading in age-related macular degeneration (AMD).

DESIGN

Retrospective cohort.

METHODS

participants: Newly diagnosed neovascular AMD patients who initiated intravitreal anti-vascular endothelial growth factor therapy by 1 physician from October 1, 2005 to December 1, 2012. interventions: Two independent graders classified the baseline lesions using FA alone and FA+OCT. main outcome measures: Analysis of the frequency of lesion subtypes by FA alone or FA+OCT and agreement between both classification systems was performed.

RESULTS

A total of 232 patients (266 eyes) fit the inclusion criteria. Mean age was 86.3 years; 67.7% of eyes (180/266) were from female patients, and 95.5% (254/266) were from white patients. The distribution using FA alone was 49.6% (132/266), 12.0% (32/266), 28.6% (76/266), and 9.8% (26/266) among occult, classic, retinal angiomatous proliferation, and mixed choroidal neovascularization, respectively. With FA+OCT, 39.9% (106/266), 9.0% (24/266), 34.2% (91/266), and 16.9% (45/266) were type 1 (sub-retinal pigment epithelium), type 2 (subretinal), type 3 (intraretinal), and mixed neovascularization (NV), respectively. The κ statistic was 0.65 (standard error ±0.37, P < .001) between the 2 classification systems, representing good agreement.

CONCLUSION

With both FA-alone and FA+OCT grading, we found a higher incidence of type 3 NV in eyes with newly diagnosed neovascular AMD than that reported in prior studies. The κ statistic between the 2 classification systems showed "good" agreement. The discrepancies are likely attributable to the identification of a higher frequency of type 3 and mixed NV and a lower frequency of type 1 NV with the aid of OCT.

The role of proteases and inflammatory molecules in triggering neovascular age-related macular degeneration: basic science to clinical relevance

Age-related macular degeneration (AMD) causes severe vision impairment in aged individuals. The health impact and cost of the disease will dramatically increase over the years, with the increase in the aging population. Currently, antivascular endothelial growth factor agents are routinely used for managing late-stage AMD, and recent data have shown that up to 15%-33% of patients do not respond to this treatment. Henceforth, there is a need to develop better treatment options. One avenue is to investigate the role proteases and inflammatory molecules might have in regulating and being regulated by vascular endothelial growth factor. Moreover, emerging data indicate that proteases and inflammatory molecules might be critical in the development and progression of AMD. This article reviews recent literature that investigates proteases and inflammatory molecules involved in the development of AMD. Gaining insights into the proteolytic and inflammatory pathways associated with the pathophysiology of AMD could enable the development of additional or alternative drug strategies for the treatment of AMD.

Pharmacokinetics, pharmacodynamics and pre-clinical characteristics of ophthalmic drugs that bind VEGF

Drugs that prevent the binding of VEGF to its trans-membrane cognate receptors have revolutionized the treatment of the most important chorioretinal vascular disorders: exudative age-related macular degeneration, diabetic macular edema, and retinal vein occlusions. Pegaptanib, which binds to VEGF165 and longer isoforms, ranibizumab and bevacizumab, which bind all VEGF-A isoforms, and aflibercept, which binds VEGF-A, VEGF-B, and placental growth factor, all bind VEGF165 with high affinity. The drugs have relatively long half-lives (7 to 10 days) after intravitreal depot injections and clinical durations of action that usually exceed 4 weeks. Plasma VEGF concentrations decrease after intravitreal injections of bevacizumab and aflibercept because their systemic half-lives are extended by their Fc fragments. Extensive in vitro and in vivo testing shows that the drugs prevent VEGF-mediated activation of endothelial cells while exhibiting little evidence of toxicity. Further anti-VEGF drug development is on-going.

Long-term stability of vascular endothelial growth factor suppression time under ranibizumab treatment in age-related macular degeneration

PURPOSE

To determine intra-individual long-term stability of vascular endothelial growth factor (VEGF) suppression time in eyes with neovascular age-related macular degeneration (AMD) treated with ranibizumab.

DESIGN

Nonrandomized, prospective clinical study.

METHODS

Eighty-three eyes of 83 patients with neovascular AMD undergoing intravitreal ranibizumab injections were included in the study. A total of 859 aqueous humor specimens were taken before each intravitreal ranibizumab injection. Vascular endothelial growth factor A was measured by multiplex bead analysis.

RESULTS

Ranibizumab resulted in complete VEGF suppression within a mean period of 36.4 days (standard deviation ±6.7 days; range, 26-69 days). Intra-individual suppression time was stable within a period of up to 3 years. Among 859 VEGF measurements, only 5 (0.58%) deviated from this pattern. Nonsuppressed VEGF levels did not differ significantly between baseline and recurrence (68.0 pg/mL vs 69.3 pg/mL) and did not correlate with choroidal neovascularization size and lesion type.

CONCLUSIONS

Both the long-term stability and the broad range of individual suppression times after ranibizumab injections would allow and justify adjustment of continuous injections individually in order to achieve permanent VEGF suppression in patients.

Characteristic findings of optical coherence tomography in retinal angiomatous proliferation

Purpose

To identify the unique pathologic findings of retinal angiomatous proliferation (RAP) in optical coherence tomography (OCT).

Methods

Retrospectively, 29 eyes of 25 patients with age-related macular degeneration and complicated RAP were analyzed. All 29 eyes had choroidal neovascularization (CNV) in the area of pigment epithelial detachment (PED) or adjacent to it, which was visible with fluorescein angiography or indocyanine green angiography. Cross-sectional images were obtained by OCT scanning through the CNV lesions.

Results

Six distinctive findings of OCT included drusen (100%), inner retinal cyst (80%), outer retinal cyst (68%), fibrovascular PED (84%), serous retinal detachment (40%), and PED (68%).

Conclusions

Through analysis of OCT findings, we revealed six different types of lesions distinctive of RAP which may provide helpful diagnostic information for subsequent treatment and predicting the prognosis of RAP.