Choroidal Neovascularization Size Research Articles

Spectral-Domain Optical Coherence Tomography Angiography Findings in Multifocal Choroiditis With Active Lesions

To describe optical coherence tomography angiography (OCTA) findings in multifocal choroiditis (MFC) with active lesions and to characterize the concordance between the OCTA and other traditional imaging modalities. Reliability and validity analysis. Patients with suspected choroidal neovascularization (CNV) or acute inflammatory lesions associated with MFC were assessed in this study. All participants underwent preliminary traditional multimodal imaging including color fundus photography, fundus autofluorescence, near-infrared reflectance imaging, spectral-domain optical coherence tomography, and fluorescence angiography (FA). The participants were prospectively recruited to perform OCTA. OCTA findings of active lesions were compared with other traditional imaging results. Vascular flow signal representing CNV was identified, and a quantitative analysis of CNV size was performed on OCTA. Fifty-two eyes of 26 MFC patients (14 were bilaterally affected and 12 were unilaterally affected) wereincluded. Among the 23 active CNV cases, 20 were confirmed on OCTA while the other 3 were invalid owing to severe motion artifacts. OCTA of CNV showed a well-circumscribed vascular network (mean flow area, 0.271mm(2) [± 0.144mm(2)]). Among the 34 inflammatory lesions in 13 eyes, 32 showed no blood flow in the outer retina on OCTA while the other 2 showed blood flow signal. OCTA has a predominant advantage in differentiating CNV from inflammatory lesions. It also allows the visualization of detailed vascular structure of CNV and the function of flow area measurement realizes the quantitative analysis of CNV. Hence, it could be an alternative option for CNV identification and may better guide treatment.

Blockage of PI3K/mTOR Pathways Inhibits Laser-Induced Choroidal Neovascularization and Improves Outcomes Relative to VEGF-A Suppression Alone.

Choroidal neovascularization (CNV) is a major cause of visual loss with age-related macular degeneration (AMD). We evaluated whether blockade of phosphatidyl-inositol-3-kinase (PI3K) and the mammalian target of rapamycin (mTOR), by impairing VEGF-A and other growth factor receptors like platelet-derived growth factor (PDGF), would reduce laser-induced CNV in mice. Choroidal neovascularization lesions were induced in C57BL/6 mice. Two groups of mice received oral GSK2126458 (3 mg/kg) or vehicle for 14 days following laser, whereas three groups were treated with GSK2126458 (6 μg/eye), aflibercept (2 μL/eye), or vehicle intravitreally on days 0 and 7 after laser. Vascular leakage was measured by fluorescein angiography (FA) on day 14. Choroidal neovascularization membranes were evaluated on choroidal flat mounts following FITC-dextran perfusion, as well as ED1 and isolectin B4 (IB4) immunohistochemistry. Oral and intravitreal (IVT) GSK2126458 reduced leakage and area of CNV lesions. Greater probability of leaking lesions (∼60%; P < 0.05) was observed in both vehicle groups. Fluorescein isothiocyanate-dextran-labeled total CNV burden area (total lesion area/eye) was reduced ∼67% (P < 0.05) and 35% (P = 0.0528) after oral and IVT GSK2126458 administration. GSK2126458 treatment reduced lesion size by ∼80% (P < 0.05) and 50% (P < 0.05) for oral and IVT control groups. Aflibercept did not alter lesion size (∼27% reduction). Phosphatidyl-inositol-3-kinase/mTOR is involved in laser-induced CNV angiogenic processes. GSK2126458 effectively reduces CNV size and leakage. Choroidal neovascularization size following IVT GSK2126458 was smaller than after oral administration. Therefore, inhibition of PI3K/mTOR pathways may be more effective due to blockade of action of multiple growth factors.

Interferon-beta signaling in retinal mononuclear phagocytes attenuates pathological neovascularization.

Age‐related macular degeneration (AMD) is a leading cause of vision loss among the elderly. AMD pathogenesis involves chronic activation of the innate immune system including complement factors and microglia/macrophage reactivity in the retina. Here, we show that lack of interferon‐β signaling in the retina accelerates mononuclear phagocyte reactivity and promotes choroidal neovascularization (CNV) in the laser model of neovascular AMD. Complete deletion of interferon‐α/β receptor (Ifnar) using Ifnar1−/− mice significantly enhanced early microglia and macrophage activation in lesion areas. This triggered subsequent vascular leakage and CNV at later stages. Similar findings were obtained in laser‐treated Cx3cr1 Cre ER:Ifnar1 fl/fl animals that allowed the tamoxifen‐induced conditional depletion of Ifnar in resident mononuclear phagocytes only. Conversely, systemic IFN‐β therapy of laser‐treated wild‐type animals effectively attenuated microgliosis and macrophage responses in the early stage of disease and significantly reduced CNV size in the late phase. Our results reveal a protective role of Ifnar signaling in retinal immune homeostasis and highlight a potential use for IFN‐β therapy in the eye to limit chronic inflammation and pathological angiogenesis in AMD.

Visual and anatomic outcomes after conversion to aflibercept in neovascular age-related macular degeneration: 12-month results.

To investigate 12-month outcomes of conversion to aflibercept in patients with neovascular age-related macular degeneration resistant to ranibizumab. Twenty-two eyes of 19 consecutive patients received 3 monthly aflibercept injections followed by a pro re nata protocol. Spectral-domain optical coherence tomography (OCT) images were obtained before each injection. All 49 cross-sectional OCT B-scans obtained in each examination were investigated and the largest choroidal neovascularization (CNV) size was chosen. The same cross-sectional B-scan sections containing the maximum CNV size were used during the follow-up. After 12 months, best-corrected visual acuity increased from 45.68 ± 20.25 to 59.09 ± 17.50 Early Treatment Diabetic Retinopathy Study letters (p&lt;0.001), central subfield thickness decreased from 399.91 ± 148.85 to 304.55 ± 97.89 μm (p = 0.003), area of CNV declined from 0.38 ± 0.24 to 0.28 ± 0.19 mm2 (p = 0.003), and macular volume improved from 9.64 ± 1.75 to 8.45 ± 0.98 mm3 (p&lt;0.001). There was a significant resolution of intraretinal fluid (p = 0.016), but reduction of subretinal fluid was not significant (p = 0.25). Visual and anatomic improvement were obtained after conversion to aflibercept.

Epimacular Brachytherapy for Previously Treated Neovascular Age-Related Macular Degeneration (MERLOT): A Phase 3 Randomized Controlled Trial

To assess the safety and efficacy of epimacular brachytherapy (EMB) for patients with chronic, active, neovascular age-related macular degeneration (AMD). Phase 3 randomized controlled trial. Patients (n= 363) with neovascular AMD already receiving intravitreal ranibizumab injections. Either pars plana vitrectomy with 24-gray EMB and ongoing pro re nata (PRN) ranibizumab (n=224) or ongoing PRN ranibizumab monotherapy (n= 119). The coprimary outcomes, at 12 months, were the number of PRN ranibizumab injections and Early Treatment of Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (VA). Secondary outcomes included the proportion of participants losing fewer than 15 ETDRS letters, angiographic total lesion size, choroidal neovascularization (CNV) size, and optical coherence tomography (OCT) foveal thickness. A predefined subgroup analysis tested the influence of baseline ocular characteristics on the response to EMB. The mean number of PRN ranibizumab injections was 4.8 in the EMB arm and 4.1 in the ranibizumab monotherapy arm (P= 0.068). The mean VA change was-4.8 letters in the EMB arm and-0.9 letters in the ranibizumab arm (95% confidence interval of difference between groups,-6.6 to-1.8 letters). The proportion of participants losing fewer than 15 letters was 84% in the EMB arm and 92% in the ranibizumab arm (P= 0.007). In the EMB arm, the mean total lesion size increased by 1.2 mm(2) versus 0.4 mm(2) in the ranibizumab arm (P= 0.27). The CNV size decreased by 0.5 mm(2) in the EMB arm and by 1.3 mm(2) in the ranibizumab arm (P= 0.27). The OCT foveal thickness decreased by 1.0 μm in the EMB arm and by 15.7 μm in the ranibizumab arm (P= 0.43). Most subgroups favored ranibizumab monotherapy, some significantly so. One participant showed retinal vascular abnormality attributed to radiation, but otherwise safety was acceptable. These results do not support the use of EMB for chronic, active, neovascular AMD. Safety isacceptable out to 12 months, but radiation retinopathy can occur later, so further follow-up is planned.

Connecting the innate and adaptive immune responses in mouse choroidal neovascularization via the anaphylatoxin C5a and γδT-cells.

Neovascular age-related macular degeneration (AMD) is characterized by choroidal neovascularization (CNV). An overactive complement system is associated with AMD pathogenesis, and serum pro-inflammatory cytokines, including IL-17, are elevated in AMD patients. IL-17 is produced by complement C5a-receptor-expressing T-cells. In murine CNV, infiltrating γδT- rather than Th17-cells produce the IL-17 measurable in lesioned eyes. Here we asked whether C5a generated locally in response to CNV recruits IL-17-producing T-cells to the eye. CNV lesions were generated using laser photocoagulation and quantified by imaging; T-lymphocytes were characterized by QRT-PCR. CNV resulted in an increase in splenic IL-17-producing γδT- and Th17-cells; yet in the CNV eye, only elevated levels of γδT-cells were observed. Systemic administration of anti-C5- or anti-C5a-blocking antibodies blunted the CNV-induced production of splenic Th17- and γδT-cells, reduced CNV size and eliminated ocular γδT-cell infiltration. In ARPE-19 cell monolayers, IL-17 triggered a pro-inflammatory state; and splenocyte proliferation was elevated in response to ocular proteins. Thus, we demonstrated that CNV lesions trigger a systemic immune response, augmenting local ocular inflammation via the infiltration of IL-17-producing γδT-cells, which are presumably recruited to the eye in a C5a-dependent manner. Understanding the complexity of complement-mediated pathological mechanisms will aid in the development of an AMD treatment.

Effect of aspirin on models of retinal pigment epithelium pathology.

To characterize the effect of aspirin (ASA) in mouse models of choroidal neovascularization (CNV) and retinal degeneration. In vivo: Male C57BL/6 mice were given ASA in food or regular rodent diet. CNV was induced by argon laser photocoagulation. Subretinal injections of polyethylene glycol 400 (PEG-400) were administered to induce retinal degeneration. CNV size, laser spot area and mean intensity of VEGF in the laser injured zones were measured. In the PEG injected eyes the thickness of retinal pigment epithelium (RPE) and choroid was measured. In vitro: Human ARPE-19 cells were treated with 0.5 or 2.0 mM/L of ASA for 72 h. ELISA was used to measure the concentration of VEGF and CCL-2 in the supernatants. Additionally, damaged RPE monolayer was treated with ASA (0.5 or 2.0 mM/L) and vehicle separately. Size of damaged area was measured. ELISA was used to measure secretion of VEGF-A and CCL-2 by damaged cells after 24 h. No statistically significant effect of ASA on CNV size, laser spot size or VEGF expression was noted in CNV model. In the PEG model, ASA did not have any effect on RPE and choroid thickness; however, a significant increase in RPE atrophy was observed (P = 0.02 + 38%). In addition, ASA had a significant effect on the ability of the RPE cells to regenerate and become confluent after mechanical damage. ASA at doses consumed clinically for various medical causes may not worsen CNV in human subjects. However, ASA may increase RPE atrophy when consumed over long periods of time.

Aflibercept for neovascular age-related macular degeneration.

Aflibercept for neovascular age-related macular degeneration.

Comparison of photodynamic therapy, ranibizumab/bevacizumab or combination in the treatment of myopic choroidal neovascularisation: a 9-year-study from a single centre

AimTo compare treatment outcomes for myopic choroidal neovascularisation (CNV) managed with verteporfin photodynamic therapy (vPDT), intravitreal antivascular endothelial growth factor (anti-VEGF, bevacizumab/ranibizumab) agents or combination thereof.MethodsClinical data of 79 eyes...

Understanding the determinants of myopic choroidal neovascularization and response to treatment.

The pathophysiologic pathways that govern the development of choroidal neovascularization (CNV) are complex. Patchy atrophy and lacquer cracks are known to be major anatomic risk factors for the development of myopic CNV, but they are not alone and much remains to be understood about other factors that influence development. In addition, a greater understanding of the modifiable and nonmodifiable factors that influence outcome, resolution, and recurrence after intravitreal injection of anti-vascular endothelial growth factor (VEGF) could lead to more personalized treatment algorithms that integrate parameters other than the presence of CNV itself and could help improve clinical outcomes and reduce recurrence. We reviewed recently published data on risk factors for CNV and predictors of response to anti-VEGF treatments. In particular, data pertaining to age, sex, genetic predisposition, baseline visual acuity, axial length, staphyloma, lacquer cracks, atrophic lesions, choroidal thickness or choroidal thinning, characteristics of CNV such as duration, localization, and size of CNV, and treatment considerations such as choice of treatment, loading doses, and combination treatments were reviewed. Our analysis showed that the body of evidence is incomplete. Additional studies are required to identify high-risk patients and to develop personalized therapeutic approaches.

FACTORS INFLUENCING NEED FOR RETREATMENT AND LONG-TERM VISUAL OUTCOME AFTER INTRAVITREAL BEVACIZUMAB FOR MYOPIC CHOROIDAL NEOVASCULARIZATION.

To evaluate the efficacy and the predictive factors associated with the need for retreatment and long-term visual outcome after intravitreal bevacizumab for myopic choroidal neovascularization (CNV). Retrospective cohort study of 93 eyes with subfoveal or juxtafoveal myopic CNV treated initially with either 3-monthly or single intravitreal bevacizumab injections followed by pro re nata retreatment. The efficacy was evaluated by the best-corrected visual acuity (BCVA) during follow-up visits. Backward stepwise multiple linear regression analyses were performed to evaluate the potential predictive factors on final BCVA, change in BCVA, and number of injections. Multiple logistic regression was performed to evaluate the potential predictive factors for retreatment. The mean follow-up duration was 25.12 ± 11.18 (SD) months. The mean logMAR BCVA at baseline was 0.72 ± 0.58 logMAR (20/100 Snellen equivalent) and was maintained at 0.39 ± 0.46 logMAR (20/50 Snellen equivalent) at the last follow-up (P < 0.001). The mean number of injections was 3.53 ± 1.70 (range, 3-10), and a total of 25 eyes (26.9%) received retreatment. Patients who received single loading injection had significantly lower mean total number of injections (1.50 ± 0.73 vs. 3.96 ± 1.53). Both subfoveal and juxtafoveal myopic CNV eyes had significant improvement in BCVA (0.28 ± 0.43 vs. 0.22 ± 0.32 [20/40 vs 20/30 Snellen equivalent], P = 0.506), and juxtafoveal myopic CNV eyes had significantly better BCVA at baseline and at the last follow-up than the subfoveal group. Treatment-naive eyes had significant improvement from baseline BCVA, and the amount of improvement was significantly more than those who received previous photodynamic therapy (0.31 ± 0.43 vs. 0.06 ± 0.11 [20/40 vs 20/25 Snellen equivalent], P < 0.001). Multivariate stepwise regression analysis showed that the baseline CNV size (P < 0.05), baseline BCVA (P < 0.001), and duration of symptoms (P < 0.05) were significant predictive factors for final BCVA, and BCVA improvement. Multiple logistic regression analysis identified that CNV size (P = 0.014) and follow-up duration (P = 0.017) were significant predictive factors for retreatment. No significant association was found for number of injections. Intravitreal bevacizumab seems to be an effective treatment for both subfoveal and juxtafoveal myopic CNV in the long term. Patients presented with shorter duration of symptoms and smaller CNV size before treatment as significant prognostic factors that predict better visual outcome. Eyes with longer follow-up duration and larger baseline CNV size may have higher risk for retreatment.

Modifying Choroidal Neovascularization Development with a Nutritional Supplement in Mice.

We examined the effect of nutritional supplements (modified Age Related Eye Disease Study (AREDS)-II formulation containing vitamins, minerals, lutein, resveratrol, and omega-3 fatty acids) on choroidal neovascularization (CNV). Supplements were administered alone and combined with intravitreal anti-VEGF in an early-CNV (diode laser-induced) murine model. Sixty mice were evenly divided into group V (oral vehicle, intravitreal saline), group S (oral supplement, intravitreal saline), group V + aVEGF (oral vehicle, intravitreal anti-VEGF), and group S + aVEGF (oral supplement, intravitreal anti-VEGF). Vehicle and nutritional supplements were administered daily for 38 days beginning 10 days before laser. Intravitreal injections were administered 48 h after laser. Fluorescein angiography (FA) and flat-mount CD31 staining evaluated leakage and CNV lesion area. Expression of VEGF, MMP-2 and MMP-9 activity, and NLRP3 were evaluated with RT-PCR, zymography, and western-blot. Leakage, CNV size, VEGF gene and protein expression were lower in groups V + aVEGF, S + aVEGF, and S than in V (all p < 0.05). Additionally, MMP-9 gene expression differed between groups S + aVEGF and V (p < 0.05) and MMP-9 activity was lower in S + aVEGF than in V and S (both p < 0.01). Levels of MMP-2 and NLRP3 were not significantly different between groups. Nutritional supplements either alone or combined with anti-VEGF may mitigate CNV development and inhibit retinal disease involving VEGF overexpression and CNV.

Predictability of Recurrent Exudation and Subretinal Hemorrhaging in Neovascular Age-Related Macular Degeneration With Indocyanine Green Angiography.

To report the predictability of recurrent exudation and subretinal hemorrhaging after treatment extension in neovascular age-related macular degeneration (AMD) through assessment of interval changes in choroidal neovascularization (CNV) size on indocyanine green (ICG) angiography. The charts of patients with neovascular AMD who underwent bevacizumab therapy using a treat-and-extend protocol were retrospectively reviewed over a 12-month period. An increase of 33% or more in CNV surface area on ICG angiography from 4 to 6 weeks, 6 to 8 weeks, and 8 to 10 weeks was observed in patients whose treatment interval could not be extended from 6 to 8 weeks, 8 to 10 weeks, and 10 to 12 weeks, respectively, and this was significant compared to patients whose treatment interval was successfully extended during those respective intervals (P < .0001, P = .0002, P = .0004, respectively). CNV size change on ICG angiography can predict which patients are likely to experience recurrent exudation and/or subretinal hemorrhaging after treatment extension using treat-and-extend bevacizumab.

Spectral-Domain Optical Coherence Tomography Angiography of Choroidal Neovascularization

To describe the characteristics as well as the sensitivity and specificity of detection of choroidal neovascularization (CNV) on optical coherence tomography angiography (OCTA) using spectral-domain optical coherence tomography. Observational, retrospective study. Seventy-two eyes of 61 subjects (48 eyes of 43 subjects with CNV, 24 eyes of 18 subjects without CNV). Patients imaged using the prototype AngioVue OCTA system (Optovue, Inc, Fremont, CA) between August 2014 and October 2014 at New England Eye Center were assessed. Patients in whom CNV was identified on OCTA were evaluated to define characteristics of CNV on OCTA: size using greatest linear dimension (small, <1 mm; medium, 1-2 mm; large, >2 mm), appearance (well-circumscribed, poorly circumscribed), and presence of subretinal and intraretinal fluid. Concurrently, an overlapping second cohort of patients who underwent same-day OCTA and fluorescein angiography (FA) for suspected CNV was evaluated to estimate sensitivity and specificity of OCTA in detecting CNV using FA as ground truth. Choroidal neovascularization appearance, CNV size, and presence of subretinal and intraretinal fluid. In 48 eyes, CNV was visualized on OCTA. Thirty-one eyes had CNV associated with neovascular age-related macular degeneration. Size of CNV was small in 23% (7/31), medium in 42% (13/31), and large in 35% (11/31). Poorly circumscribed vessels, subretinal fluid, and intraretinal fluid each were seen in 71% (22/31). Seven eyes had CNV associated with central serous chorioretinopathy. Size of CNV was small in 71% (5/7) and large in 29% (2/7). Seventy-one percent (5/7) had well-circumscribed vessels, 86% (6/7) had subretinal fluid, and 14% (1/7) had intraretinal fluid. Thirty eyes with OCTA and same-day FA were evaluated to determine sensitivity and specificity of CNV detection on OCTA. Sensitivity was 50% (4/8) and specificity was 91% (20/22). Using OCTA allows the clinician to visualize CNV noninvasively and may provide a method for identifying and guiding treatment of CNV. The specificity of CNV detection on OCTA compared with FA seems to be high. Future studies with larger sample sizes are needed to elaborate better on the sensitivity and specificity of CNV detection and to illustrate clinical usefulness.

Evaluation of Idiopathic Choroidal Neovascularization with Indocyanine Green Angiography in Patients Undergoing Bevacizumab Therapy.

Purpose. To examine the clinical implications of change in choroidal neovascularization (CNV) size on indocyanine green (ICG) angiography in subjects with idiopathic CNV undergoing bevacizumab therapy. Methods. The charts of subjects with an idiopathic CNV treated by a modified PRN regimen with intravitreal bevacizumab over a 12-month period were retrospectively reviewed. Results. There were 34 subjects included in the analysis. Baseline CNV sizes of less than 1.0 mm2 on ICG angiography correlated with complete CNV resolution (P = 0.0404), fewer injections delivered (P = 0.0002), and better Snellen visual acuity (P = 0.0098) at 12 months. Subjects that experienced a 33% or more reduction in CNV size on ICG angiography at 2 months had complete CNV resolution (P = 0.0047) and fewer injections (P < 0.0001) at 12 months compared to subjects that did not experience a 33% or more reduction in CNV size on ICG angiography at 2 months. Conclusions. Smaller baseline CNV size on ICG angiography resulted in better visual acuity and fewer injections at 12 months, and a reduction of 33% or more in CNV size after 2 months may predict a better clinical course in subjects with idiopathic CNV undergoing bevacizumab therapy.

Prognostic factors of early morphological response to treatment with ranibizumab in patients with wet age-related macular degeneration.

Aim. To assess the significance of age, gender, baseline best corrected visual acuity, baseline macula thickness, and type and size of choroidal neovascularization in early morphological therapeutic response to ranibizumab treatment in patients with the wet form of age-related macular degeneration. Methods. From 09/2008 to 06/2013 we evaluated 1153 newly diagnosed, treatment-naïve patients treated with ranibizumab. Based on the morphological findings in the macula following the initial 3 injections of ranibizumab, the patients were divided into two groups based on active and inactive choroidal neovascularization. Results. After the initial 3 injections of ranibizumab, we examined the sample of 841 eyes with active CNV and 312 eyes with inactive CNV. In the inactive group, we found a statistically higher proportion of occult CNV (P < 0.001) and lower incidence of CNV greater than 5DA (P < 0.001) compared with the active group. We found no statistically significant difference in age, gender, baseline best corrected visual acuity, or baseline macula thickness between the inactive and active groups. Conclusion. Occult CNV and CNV smaller than 5DA are optimistic factors for a better morphological therapeutic response at the beginning of ranibizumab treatment.

Predictability of Recalcitrance in Neovascular Age-Related Macular Degeneration With Indocyanine Green Angiography.

This study aimed to evaluate the utility of indocyanine green (ICG) angiography in predicting recalcitrance in neovascular age-related macular degeneration (nAMD). A retrospective case series. The charts of treatment-naive subjects with nAMD undergoing anti-vascular endothelial growth factor (anti-VEGF) therapy during a 6-month period were retrospectively reviewed. The study group consisted of subjects with persistent retinal edema on optical coherence tomography (OCT) despite 6 consecutive monthly anti-VEGF injections. The control group was age-matched to the study group and consisted of subjects who demonstrated complete resolution of retinal edema on OCT after 3 or fewer monthly anti-VEGF injections. There were 42 study cases and 42 controls included in the analysis. The baseline visual acuity, central macular thickness on OCT, and choroidal neovascularization (CNV) surface area on ICG angiography were statistically similar between the study and control groups. The CNV surface area on ICG angiography 2 months after starting consecutive monthly anti-VEGF injections increased from a baseline of 1.78 ± 0.86 to 2.66 ± 0.92 mm2 in the study group (P = 0.008) and decreased from a baseline of 1.94 ± 0.97 to 1.12 ± 0.05 mm2 in the control group (P = 0.04); this change in CNV size on ICG angiography from baseline to 2-month follow-up was statistically significant between the study and control groups (P < 0.0001). Change in CNV surface area on ICG angiography can predict which subjects with nAMD are likely to have persistent retinal edema on OCT after 6 or more consecutive monthly anti-VEGF injections.

Antiproliferative, Apoptotic, and Autophagic Activity of Ranibizumab, Bevacizumab, Pegaptanib, and Aflibercept on Fibroblasts: Implication for Choroidal Neovascularization.

Purpose. Choroidal neovascularization (CNV) is one of the most common complications of retinal diseases accompanied by elevated secretion of vascular endothelial growth factor (VEGF). Intravitreal anti-VEGFs (ranibizumab, bevacizumab, pegaptanib, and aflibercept) can suppress neovascularization, decrease vascular permeability and CNV size, and, thereby, improve visual function. The antiproliferative, apoptotic, and autophagic effect of anti-VEGF drugs on fibroblasts found in CNVs has not been yet explored. Methods. Concentration-dependent cellular effects of the four anti-VEGFs were examined in L929 fibroblasts over a 5-day period. The cell survival, mitotic and polykaryocytic indices, the level of apoptosis and autophagy, and the cellular growth kinetics were all assessed. Results. The anti-VEGFs could inhibit the survival, mitotic activity, and proliferation as well as increase the cellular heterogeneity, apoptosis, and autophagy of the fibroblasts in a dose-dependent manner. Cellular growth kinetics showed ranibizumab to be less aggressive, but three other anti-VEGFs showed higher antiproliferative and apoptotic activity and expressed negative cellular growth kinetics. Conclusions. The antiproliferative, apoptotic, and autophagic activity of anti-VEGFs upon fibroblasts may explain the cellular response and the etiology of CNV involution in vivo and serve as a good study model for CNV in vitro.

Effect of ranibizumab on high-speed indocyanine green angiography and minimum intensity projection optical coherence tomography findings in neovascular age-related macular degeneration.

The purpose of this 1-year prospective study was to investigate how induction/pro re nata ranibizumab intravitreal treatment of eyes with neovascular age-related macular degeneration affects the anatomy of choroidal neovascularization (CNV) and the overlying outer retinal tissue. High-speed indocyanine green (HS-ICG) angiography measurements provided quantification of the CNV size in 60 patients followed for 1 year. Minimum intensity projection optical coherence tomography (MinIP OCT), a novel algorithm assessing minimum optical intensity between the internal limiting membrane and retinal pigment epithelium, measured the area of outer retinal disruption overlying the CNV. Fluorescein angiography was also assessed to evaluate late retinal leakage. After 1 year, the mean area of CNV measured with indocyanine green angiography decreased by 5.8%. The mean area of MinIP OCT of outer retinal disruption overlying the CNV decreased by 4.2%. Mean area of fluorescein angiography leakage decreased by 6.3%. Both the area of outer retinal disruption measured with MinIP OCT and the area of leakage on fluorescein angiography typically exceeded the area of CNV on indocyanine green angiography at baseline and 1 year. Choroidal neovascularization treated with induction/pro re nata intravitreal ranibizumab for 1 year essentially remained static. Minimum intensity projection optical coherence tomography suggests that the area of outer retinal disruption overlying the CNV may be greater than the CNV itself and often correlates with the leakage area on fluorescein angiography. Additionally, there was minimal change in the area of outer retinal disruption on MinIP OCT even when fluid resolved. Measurements of the extent of CNV lesions based on indocyanine green angiography and MinIP OCT may provide useful outcome variables to help assess the CNV complex longitudinally and warrant further validation.

Suppression of laser-induced choroidal neovascularization by intravitreal injection of tristetraprolin.

To examine the effect of intravitreal adenoviral vector-mediated tristetraprolin (Ad-TTP) on VEGF mRNA expression in a rat model of laser-induced choroidal neovascularization. Ad-TTP was prepared using a commercial kit. Retinal laser-induced photocoagulation (10 spots per eye) was performed on rats in this experimental choroidal neovascularization (CNV) model. Rats were divided into four groups: control (single intravitreal injection of balanced salt solution, n=10), laser-induced CNV (photocoagulation only, n=20), laser-induced CNV plus Ad-TTP injection (photocoagulation plus a single intravitreal Ad-TTP injection, n=20) and Ad-TTP injection only (n=10). Changes in choroidal morphology were evaluated in ten rats in the laser only and the laser plus Ad-TTP groups. Two weeks after laser injury, the size of CNV was calculated by perfusion with high-molecular-weight fluorescein isothiocyanate (FITC)-dextran. VEGF mRNA expression in retina-choroid tissue from ten rats in each group was measured by reverse transcription polymerase chain reaction (RT-PCR). Two weeks after treatment, the area of laser-induced CNV was reduced by approximately 60% in the rats given the Ad-TTP injection compared with that in the laser-only group. There was a tendency toward decreased VEGF mRNA expression in the Ad-TTP injection groups. A single intravitreal injection of Ad-TTP significantly suppressed CNV size in this experimental laser-induced CNV model. Ad-TTP injection also decreased VEGF mRNA expression compared with that in the laser-induced CNV group. The present study is meaningful as the first study to investigate the effect of tristetraprolin delivered via intravitreal injection.