Central retinal vein occlusion: modifying current treatment protocols

Long-Term Outcomes in Early versus Limited Response to Anti-VEGF Treatment for Retinal Vein Occlusion

OBJECTIVE

Macular edema secondary to retinal vein occlusion (RVO) is a sight-threatening condition. Previous studies showed that early responders (ERs) who respond well to anti-VEGF injections within 3 months of treatment have better outcomes, as measured by best visual acuity (BVA) and central subfield thickness (CST) at 12 months postinjection initiation compared with limited early responders (LERs). This study analyzed whether ER eyes continue to respond better than LER eyes over longer periods. This study also aimed to identify baseline comorbidities associated with response status.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients aged > 18 years with RVO-related macular edema treated with anti-VEGF injections.

METHODS

Patients were categorized as ERs or LERs. Limited early responder eyes were defined as having CST reduction < 10%, BVA gain < 5 ETDRS letters, or both at 3 months after anti-VEGF initiation. Best visual acuity and CST changes over the 24- and 36-month period after the first anti-VEGF treatment were compared between ERs and LERs. Patient characteristics and systemic comorbidities were identified by chart review. Statistical analysis involved the Levene test, Welch t test, and Welch analysis of variance.

MAIN OUTCOME MEASURES

Best visual acuity and CST changes over the initial 24-month and 36-month periods after treatment.

RESULTS

The 24-month cohort included 68 ERs and 39 LERs, and the 36-month cohort included 58 ERs and 33 LERs. At the 24-month time point, there were significant differences in BVA and CST gains between ERs (+19.8 letters, -221.2 um) and LERs (-2.4 letters, -90.1 um; P < 0.001, P < 0.01). Similarly, at 36 months, there were significant differences in BVA and CST gains between ERs (+17.7 letters, -229.3 um) and LERs (+1.3 letters, -128 um; P < 0.001, P < 0.05). After controlling for differences in baseline BVA and CST, only the 24-month change in BVA remained significant (P < 0.001). There were no significant associations between response status and cardiopulmonary, endocrine, and oncologic comorbidities.

CONCLUSIONS

Early responder eyes with branched retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) have better functional responses to anti-VEGF injections at 24 months compared with LER eyes, even after controlling for baseline differences. Early identification of eyes as ERs or LERs in BRVO and CRVO may predict long-term functional prognoses.

FINANCIAL DISCLOSURE(S)

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

Efficacy of a Modified Treat-and-Extend Aflibercept Regimen for Macular Oedema in Eyes with Central Retinal Vein Occlusion: 2-Year Prospective Study

This prospective, multicentre, interventional study evaluated the efficacy of a modified treat-and-extend (mTAE) aflibercept regimen as personalized therapy for macular oedema (MO) due to central retinal vein occlusion (CRVO). Fifty eyes were studied from 50 patients who were enrolled between November 2016 and July 2019. All patients received intravitreal aflibercept (IVA) injections on an mTAE regimen for 24 months. Primary outcome measures were best-corrected visual acuity (BCVA) and central subfield thickness (CST) at 12 months. Secondary endpoints were BCVA and CST at 24 months. Mean (standard deviation) baseline BCVA (logMAR) and CST were 0.50 (0.51) and 557 (240) µm, respectively. BCVA and CST showed significant improvements at month 12 (0.19 (0.38) and 275 (98) µm, respectively; both p < 0.0001, paired t-test). BCVA and CST also showed significant improvements at 24 months (0.26 (0.50) and 255 (91) µm, respectively, p = 0.0004 and p < 0.0001, paired t-test). The mean numbers of IVA injections and clinic visits over the 24-month study period were 6.2 (3.0) and 10.3 (1.0), respectively. The mTAE regimen of IVA injections for MO due to CRVO was effective in improving BCVA and decreasing CST at 24 months. The mTAE regimen might be an effective personalized therapy for CRVO.

Real-World Outcomes of Ranibizumab Treatment in French Patients with Visual Impairment due to Macular Edema Secondary to Retinal Vein Occlusion: 24-Month Results from the BOREAL-RVO Study

INTRODUCTION

Information about real-world ranibizumab use is needed to optimize treatment of macular edema secondary to retinal vein occlusion (RVO). The BOREAL-RVO study assessed treatment use, effectiveness, and safety of 24-month treatment with ranibizumab 0.5 mg in patients with visual impairment due to macular edema secondary to RVO in a real-world setting.

METHODS

This was a multicenter, post-authorization, observational study in France, including patients starting ranibizumab for RVO. Primary endpoint was mean change from baseline in best-corrected visual acuity (BCVA) at month 6. Secondary endpoints were mean changes from baseline in BCVA at month 24 and central retinal thickness (CRT) at months 6 and 24, and treatment use in real-world setting.

RESULTS

226 branch RVO (BRVO) and 196 central RVO (CRVO) patients were enrolled; 71.7% and 70.9% completed the 24-month follow-up, respectively. In BRVO, mean (SD) baseline BCVA was 55.2 (18.7) letters, with gains of 14.3 (13.7), 14.1 (16.5), 13.0 (17.5), and 11.4 (20.1) letters at months 3, 6, 12, and 24, respectively. In CRVO, mean (SD) baseline BCVA was 40.4 (25.6) letters, with gains of 16.0 (21.2), 9.5 (25.4), 9.2 (27.7), and 8.3 (23.8) letters at months 3, 6, 12, and 24, respectively. At month 24, 52% of BRVO and 41% of CRVO patients had gains of 15 or more letters. In BRVO, mean (SD) CRT values at baseline and months 3, 6, 12, and 24 were 550 (175), 315 (104), 343 (122), 335 (137), and 340 (105) μm. In CRVO, mean (SD) CRT values at baseline and months 3, 6, 12, and 24 were 643 (217), 327 (152), 400 (203), 379 (175), and 348 (161) μm. On average, BRVO patients had 3.8 injections for 6.9 visits by month 6, and 7.2 injections for 19.7 visits by month 24. CRVO patients had 2.7 injections for 4.2 visits by month 6 and 7.1 injections for 21.1 visits by month 24. Factors predictive of better BCVA gain at month 6 were age under 60 at baseline, lower baseline BCVA and BCVA gain at month 3. There were no new safety findings.

CONCLUSION

Major improvements in BCVA and CRT were observed at month 3 after the induction phase and then were sustained up to month 24, with a slight decrease, probably due to under-treatment. This study demonstrated ranibizumab to be a safe and effective treatment for BRVO and CRVO in the real-world setting, although more regular or proactive treatment could further improve outcomes.

New individualized aflibercept treatment protocol for branch retinal vein occlusion with macular edema

We evaluated the long-term (24-month) efficacy of a novel individualized treatment protocol with 2 mg aflibercept for treatment-naive BRVO with macular edema. Each patient received an initial aflibercept injection and was then examined every 2 weeks until recurrence of edema. At recurrence, each patient received a second injection of aflibercept. The period of efficacy was defined as the time between the first and second injections. Subsequently, each patient was examined and re-injected with aflibercept at their personalized treatment interval, which was defined as 1 week shorter than the period of efficacy. Thirty-seven eyes of 48 patients showed recurrence after the initial injection. The mean period of efficacy was 92.5 ± 40.8 days, and the mean number of visits before recurrence, 7.6 ± 2.9. The mean 24-month best corrected visual acuity (BCVA) was significantly better than the mean baseline BCVA but significantly worse than the best BCVA during the period of efficacy. The mean gain of BCVA at 24 months was 0.07 ± 0.18 logMAR. The mean 24-month central macular thickness (CMT) was significantly lower than the mean baseline CMT but showed no difference from the mean best CMT (p = 0.060). The mean total number of visits during the 24 months was 15.8 ± 3.4. We conclude that the individualized treatment protocol that was based on the period of efficacy in treatment-naïve BRVO eyes with macular edema achieved satisfactory long-term visual outcome.

Deletion of Tgfβ signal in activated microglia prolongs hypoxia-induced retinal neovascularization enhancing Igf1 expression and retinal leukostasis

Retinal neovascularization (NV) is the major cause of severe visual impairment in patients with ischemic eye diseases. While it is known that retinal microglia contribute to both physiological and pathological angiogenesis, the molecular mechanisms by which these glia regulate pathological NV have not been fully elucidated. In this study, we utilized a retinal microglia-specific Transforming Growth Factor-β (Tgfβ) receptor knock out mouse model and human iPSC-derived microglia to examine the role of Tgfβ signaling in activated microglia during retinal NV. Using a tamoxifen-inducible, microglia-specific Tgfβ receptor type 2 (Tgfβr2) knockout mouse [Tgfβr2 KO (ΔMG)] we show that Tgfβ signaling in microglia actively represses leukostasis in retinal vessels. Furthermore, we show that Tgfβ signaling represses expression of the pro-angiogenic factor, Insulin-like growth factor 1 (Igf1), independent of Vegf regulation. Using the mouse model of oxygen-induced retinopathy (OIR) we show that Tgfβ signaling in activated microglia plays a role in hypoxia-induced NV where a loss in Tgfβ signaling microglia exacerbates and prolongs retinal NV in OIR. Using human iPSC-derived microglia cells in an in vitro assay, we validate the role of Transforming Growth Factor-β1 (Tgfβ1) in regulating Igf1 expression in hypoxic conditions. Finally, we show that Tgfβ signaling in microglia is essential for microglial homeostasis and that the disruption of Tgfβ signaling in microglia exacerbates retinal NV in OIR by promoting leukostasis and Igf1 expression.

Treat-and-extend regimens of anti-vascular endothelial growth factor therapy for retinal vein occlusions: a systematic review and meta-analysis

OBJECTIVE

To investigate treat-and-extend (T&E) regimens of anti-vascular endothelial growth factor (anti-VEGF) therapy for the treatment of macular oedema secondary to retinal vein occlusions (RVOs).

METHODS

Ovid MEDLINE, Ovid EMBASE and CENTRAL were searched on 25 February 2021. Randomized controlled trials, cohort studies, case-control studies and case series were included. The primary outcome was the change in Early Treatment Diabetic Retinopathy Score (ETDRS) letters from baseline. Conversions from Snellen to ETDRS letters were performed utilizing a published protocol. Secondary outcomes included improvement in retinal thickness from baseline, number of anti-VEGF injections and frequency of adverse events. Outcomes were examined at 12 and 24 months. Certainty of evidence was assessed utilizing GRADE (Grading of Recommendations Assessments, Development and Evaluations) guidelines.

RESULTS

Seven hundred eighty-six eyes from 16 studies were included. Meta-analysis demonstrated a mean improvement of 15.7 (95% CI: 13.3-18.0) ETDRS letters at 12 months. Central retinal thickness improved 269.7 μm (95% CI: 233.64-305.90) at 12 months. Injections were performed 8.1 (95% CI: 7.4-8.7) and 13.1 (95% CI: 9.4-16.8) times at 12 and 24 months respectively. Adverse events were infrequent across all studies. Grading of Recommendations Assessments, Development and Evaluations (GRADE) certainty of evidence was very low across all outcomes.

CONCLUSIONS

The results support the viability of T&E regimens for the treatment of macular oedema secondary to RVOs.

Retinal oximetry does not predict 12-month visual outcome after anti-VEGF treatment for central retinal vein occlusion: A multicentre study

PURPOSE

Central retinal vein occlusion (CRVO) entails retinal hypoxia that often causes visual impairment. It has been shown that oxygen saturation in larger retinal vessels correlates with the visual acuity at the time of diagnosis of CRVO but has no predictive value for the visual outcome in patients treated with anti-VEGF medication after 3 months. However, assessing the predictive value of retinal oxygen saturation after 12 months is essential because this is when the main restitution after CRVO occurs.

METHODS

Retinal oximetry was performed in 117 patients referred with CRVO to three European centres. The correlation between oxygen saturation and visual acuity at baseline and the predictive value of oxygen saturation in larger retinal vessels for the 12-month visual outcome after treatment with anti-VEGF medication were studied.

RESULTS

In the affected eye, the oxygen saturation was significantly higher in the arterioles, significantly lower in the venules, and the arterio-venous (A-V) significantly higher than in the unaffected eye (p < 0.001 for all comparisons). Correlations between best-corrected visual acuity (BCVA) and oxygen saturations were moderate and negative for arterioles (p < 0.001), positive for venules (p = 0.03) and negative for the A-V difference (p = 0.001). Best-corrected visual acuity (BCVA), but not oxygen saturation or the other explanatory variables at baseline, contributed significantly to predicting BCVA after 12 months.

CONCLUSION

Retinal vessel oxygen saturation is affected in CRVO, and saturation correlates with BCVA. However, retinal oximetry cannot replace measures of visual function as a predictor of visual outcome after 12 months of anti-VEGF treatment for CRVO.

Optical-coherence tomography angiography and ultrawide-field angiography findings in eyes with refractory macular edema secondary to retinal vein occlusion switched to aflibercept: A subanalysis from a 48-week prospective study

PURPOSE:

To evaluate anatomical changes on ultra-wide-field fluorescein-angiography and optical coherence angiography (OCT-A) among a cohort with treatment-resistant macular edema secondary to retinal vein occlusions (RVO) switched to aflibercept.

MATERIALS AND METHODS:

Patients with persistent macular edema despite previous bevacizumab and/or ranibizumab were switched to aflibercept in a 48-week prospective trial. Ultra-wide-field fluorescein angiography (UWFFA) and OCT-A were performed at baseline, week-24 and week-48. The ischemic index was calculated from UWFFA and the areas of vascular perfusion. The foveal avascular zone (FAZ) were quantitatively evaluated on OCT-A.

RESULTS:

Eighteen patients (mean age, 70.3±8.6 years) were recruited. Mean central macular thickness (CMT) was significantly reduced at 48-weeks compared to baseline (-87.6±48.8 μm, P < 0.001 and -191.0±128.3μm, P < 0.001 among BRVO and CRVO eyes, respectively). The mean baseline ischemic index as measured on Optos wide-field angiography was 10.9%±8.3 and decreased to 5.7%±4.2 (P = 0.028), at week 48. The mean FAZ areas of the SCP and DCP reduced by -0.06 ± 0.12 mm 2 and -0.17± 0.45 mm 2 , respectively. FAZ area on OCT-A was stable in eyes with stable or improved vision but increased in size in eyes with baseline macular ischemia and those with lower gains in BCVA at week 48 (R 2 =0.719, P = 0.05 and R 2 =0.516, P = 0.01).

CONCLUSION:

There was a reduction in macular edema measured on OCT at 48-weeks in eyes switched to aflibercept with chronic macular edema due to retinal vein occlusion. There was also a reduction in retinal ischemia as measured using UWFFA.

The randomized ZIPANGU trial of ranibizumab and adjunct laser for macular edema following branch retinal vein occlusion in treatment-naïve patients

The ZIPANGU study assessed the efficacy and safety of ranibizumab as a one loading dose + pro re nata (one + PRN) regimen with/without focal/grid laser among treatment-naïve patients suffering from macular edema (ME) following branch retinal vein occlusion (BRVO). ZIPANGU was a phase IV, prospective, randomized, open-label, active-controlled, 12-month, two-arm, multicenter study. Treatment-naïve patients with visual impairment (19–73 letters) caused by ME, defined as central subfield thickness (CSFT) > 300 µm, due to BRVO were randomly assigned to ranibizumab monotherapy (n = 29) or combination therapy (ranibizumab + focal/grid short-pulse laser, n = 30). The primary endpoint was the number of ranibizumab injections. Secondary endpoints were mean changes in best-corrected visual acuity (BCVA) and CSFT, and safety. There were no statistically significant differences in the mean number of ranibizumab injections between monotherapy (4.3 injections) vs. combination (4.1 injections) therapy, or in CSFT. BCVA improvement in the monotherapy arm (22.0 letters) was better than the combination therapy arm (15.0 letters) (p = 0.035). Overall, both regimens appeared to be safe and well tolerated. One + PRN ranibizumab is safe and efficacious in treatment-naïve patients with ME secondary to BRVO. A conjunctive laser treatment did not lead to better functional outcomes or fewer ranibizumab injections.

An allosteric peptide inhibitor of HIF-1α regulates hypoxia-induced retinal neovascularization

Retinal neovascularization (NV), a leading cause of vision loss, results from localized hypoxia that stabilizes the hypoxia-inducible transcription factors HIF-1α and HIF-2α, enabling the expression of angiogenic factors and genes required to maintain homeostasis under conditions of oxygen stress. HIF transcriptional activity depends on the interaction between its intrinsically disordered C-terminal domain and the transcriptional coactivators CBP/p300. Much effort is currently directed at disrupting protein-protein interactions between disease-associated transcription factors like HIF and their cellular partners. The intrinsically disordered protein CITED2, a direct product of HIF-mediated transcription, functions as a hypersensitive negative regulator that attenuates the hypoxic response by competing allosterically with HIF-1α for binding to CBP/p300. Here, we show that a peptide fragment of CITED2 is taken up by retinal cells and efficiently regulates pathological angiogenesis in murine models of ischemic retinopathy. Both vaso-obliteration (VO) and NV were significantly inhibited in an oxygen-induced retinopathy (OIR) model following intravitreal injection of the CITED2 peptide. The CITED2 peptide localized to retinal neurons and glia, resulting in decreased expression of HIF target genes. Aflibercept, a commonly used anti-VEGF therapy for retinal neovascular diseases, rescued NV but not VO in OIR. However, a combination of the CITED2 peptide and a reduced dose of aflibercept significantly decreased both NV and VO. In contrast to anti-VEGF agents, the CITED2 peptide can rescue hypoxia-induced retinal NV by modulating the hypoxic response through direct competition with HIF for CBP/p300, suggesting a dual targeting strategy for treatment of ischemic retinal diseases and other neovascular disorders.

Results from the Population-Based Gutenberg Health Study Revealing Four Altered Autoantibodies in Retinal Vein Occlusion Patients

Purpose

Retinal vein occlusion (RVO) is the second most common retinal vascular disease and a major cause of visual impairment. In this study, we aimed to observe whether RVO cases have different antibody profiles as a new potential risk factor and whether a conversion of retinal vein occlusion (RVO) to neovascular glaucoma (NVG), one of the major complications, is occurring within a 5-year timeframe.

Methods

We performed a nested case-control study (1 : 4) within the Gutenberg Health Study (GHS), a population-based, prospective cohort study in the Rhine-Main Region of Germany including 15,010 participants. RVO subjects (n = 59) were identified by grading of fundus photographs. Optic nerves of RVO subjects and age- and sex-matched controls (n = 229) at baseline and their follow-up examination after 5 years were analyzed for glaucomatous alterations. Of all RVO subjects and controls, serum autoantibody profiles were measured using in-house manufactured antigen-antibody microarrays.

Results

Of the 59 RVO patients, 3 patients (5%) showed glaucomatous optic disc alterations at baseline, whereas no new glaucoma case was detected at 5-year follow-up. Four of the autoantibodies measured (against dermcidin, neurotrophin-3, superoxide dismutase 1, and signal recognition particle 14 kDa protein) were significantly increased in the serum of RVO patients (p < 0.001). Multivariable conditional logistic regression analysis showed that 3 of these 4 antibodies were independent of cardiovascular risk factors.

Conclusions

We found several autoantibodies associated with RVO, targeting proteins and structures possibly involved in RVO pathogenesis.

Rebound Phenomenon after Intravitreal Injection of Triamcinolone Acetonide for Macular Edema

INTRODUCTION

The aim of this article was to report on a rebound phenomenon after intravitreal triamcinolone acetonide (IVTA) injection for macular edema secondary to diabetic retinopathy (DR) and central or branch retinal vein occlusion (CRVO/BRVO).

METHODS

The data were analyzed retrospectively. Complete ophthalmic examinations, including spectral domain optical coherence tomography, were performed before and 2 months after IVTA injection. The incidence of a rebound phenomenon was defined as an increase in central retinal thickness of >10% from baseline at 2 months after IVTA injection.

RESULTS

This retrospective study included 211 consecutive patients (268 eyes). One hundred ninety (71.2%), 39 (14.6%), and 39 (14.6%) eyes had macular edema (ME) due to DR, CRVO, and BRVO. In total, 9.7% of the eyes showed a rebound phenomenon (DR: 9.5%, CRVO: 5.2%, BRVO: 15.4%). The mean number of prior injections of vascular endothelial growth factor inhibitor or corticosteroid agent was statistically significantly higher in the rebound group (6.8 vs. 5.3) than in the nonrebound group (p = 0.01).

CONCLUSION

Our study shows that 9.7% of the eyes with ME secondary to DR and RVO developed a rebound phenomenon following IVTA injection, limiting its therapeutic effect. We found an increased number of prior intravitreal pharmacotherapy to be a risk factor for a rebound phenomenon.

The CD40-ATP-P2X 7 Receptor Pathway: Cell to Cell Cross-Talk to Promote Inflammation and Programmed Cell Death of Endothelial Cells

Extracellular adenosine 5′-triphosphate (ATP) functions not only as a neurotransmitter but is also released by non-excitable cells and mediates cell–cell communication involving glia. In pathological conditions, extracellular ATP released by astrocytes may act as a “danger” signal that activates microglia and promotes neuroinflammation. This review summarizes in vitro and in vivo studies that identified CD40 as a novel trigger of ATP release and purinergic-induced inflammation. The use of transgenic mice with expression of CD40 restricted to retinal Müller glia and a model of diabetic retinopathy (a disease where the CD40 pathway is activated) established that CD40 induces release of ATP in Müller glia and triggers in microglia/macrophages purinergic receptor-dependent inflammatory responses that drive the development of retinopathy. The CD40-ATP-P2X₇ pathway not only amplifies inflammation but also induces death of retinal endothelial cells, an event key to the development of capillary degeneration and retinal ischemia. Taken together, CD40 expressed in non-hematopoietic cells is sufficient to mediate inflammation and tissue pathology as well as cause death of retinal endothelial cells. This process likely contributes to development of degenerate capillaries, a hallmark of diabetic and ischemic retinopathies. Blockade of signaling pathways downstream of CD40 operative in non-hematopoietic cells may offer a novel means of treating diabetic and ischemic retinopathies.

Classification of Strokes in Patients Receiving Intravitreal Anti-Vascular Endothelial Growth Factor

BACKGROUND AND OBJECTIVE

The purpose of this study was to identify the differences in the types of strokes seen in patients receiving intravitreal anti-vascular endothelial growth factor (VEGF) compared with normal control populations.

PATIENTS AND METHODS

We performed a retrospective consecutive review of all patients receiving intravitreal anti-VEGF injections in Olmsted County, Minnesota, from January 1, 2004, to December 31, 2013, for exudative age-related macular degeneration (AMD), diabetic macular edema (DME), proliferative diabetic retinopathy (PDR), or retinal vein occlusion (RVO). A 2-year follow-up period was required for study inclusion. Three age- and sex-matched cohorts were identified.

RESULTS

A total of 2,541 patients were examined. There were 690 patients identified during the study period as receiving an intravitreal injection for AMD, DME, PDR, or RVO. Of these patients, 38 (5.8%) suffered a stroke after starting intravitreal injection therapy. Of these strokes, 27 (71.1%) were ischemic, six (15.8%) were embolic, and five (13.2%) were hemorrhagic. There were no differences in the types of strokes identified among the patients receiving intravitreal injections between the case cohort and the control cohorts (P > .05 for all).

CONCLUSION

The authors' data suggest there is no predilection to the development of ischemic infarcts or hemorrhagic strokes in those patients receiving intravitreal anti-VEGF compared with control populations. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e140-e157.].

Suprachoroidally injected pharmacological agents for the treatment of chorio-retinal diseases: a targeted approach

Delivery of pharmaceuticals to the posterior segment presents challenges that arise from the anatomy and clearance pharmacokinetics of the eye. Systemic and several local administration options [topical, periocular, intravitreal (IVT) and subretinal] are in clinical use, each with a unique benefit to risk profile shaped by factors including the administered agent, frequency of dosing, achievable pharmaceutical concentrations within posterior segment structures versus elsewhere in the eye or the body, invasiveness of the procedure and the inherent challenges with some administration methods. The use of the suprachoroidal space (SCS), which is the region between the sclera and the choroid, is being explored as a potential approach to target pharmacotherapies to the posterior segment via a minimally invasive injection procedure. Preclinical data on agents such as vascular endothelial growth factor inhibitors and triamcinolone acetonide (TA) indicate that administration via suprachoroidal injection results in more posterior distribution of the pharmacologic agent, with higher exposure to the sclera, choroid, retinal pigment epithelium cells and retina, and lesser exposure to the anterior segment, than observed with IVT administration. Based in part on these findings, clinical trials have explored the efficacy and safety of suprachoroidal administration of pharmacologic therapies in conditions affecting the posterior segment. Data on a proprietary formulation of TA administered by suprachoroidal injection show improvement in anatomic and visual outcomes in subjects with noninfectious uveitis, with the potential to mitigate the known risks of cataract and increased intraocular pressure (IOP) associated with the use of intraocular corticosteroids. Suprachoroidal administration appears to be a promising treatment modality and is also in the early stages of investigation for other possible applications, such as injection of antiglaucoma agents into the anterior SCS for long-lasting control of elevated IOP, and as a mode of delivery for gene- or cell-based therapies for retinal disorders.

Impact of Baseline Retinal Nonperfusion and Macular Retinal Capillary Nonperfusion on Outcomes in the COPERNICUS and GALILEO Studies

PURPOSE

To evaluate the impact of baseline retinal capillary nonperfusion (RNP) and macular retinal capillary nonperfusion (MNP) status on outcomes at week 24 (W24).

DESIGN

Post hoc analyses of 2 phase 3, randomized, double-masked, multicenter, sham-controlled studies.

PARTICIPANTS

Three hundred sixty-six patients with macular edema secondary to central retinal vein occlusion randomized in COPERNICUS and GALILEO.

METHODS

We randomized patients 3:2 to receive intravitreal aflibercept 2 mg every 4 weeks or sham injections until W24. RNP and MNP were assessed by a masked independent reading center.

MAIN OUTCOME MEASURES

Proportion of patients with 10 disc areas (DA) or more of RNP and any degree of MNP at W24, relative risks of 10 DA or more of RNP or any degree of MNP at W24 developing, change from baseline in best-corrected visual acuity (BCVA) and central retinal thickness (CRT) by baseline RNP and MNP status, and relationship between baseline RNP and MNP status.

RESULTS

At baseline, 24.6% of patients showed 10 DA or more of RNP and 72.6% showed MNP, regardless of baseline RNP status. At W24, the pooled proportions of patients in the intravitreal aflibercept and sham groups with 10 DA or more of RNP were 11.6% and 29.0%, respectively (P = 0.0001); the respective proportions with any degree of MNP were 61.2% and 79.5% (P = 0.0008). Relative risks and 95% confidence intervals for intravitreal aflibercept versus sham were 0.4 (0.25-0.62) for 10 DA or more of RNP and 0.8 (0.68-0.90) for MNP, indicating a lower risk for these outcomes with intravitreal aflibercept than with sham. Mean BCVA change was greater in intravitreal aflibercept- versus sham-treated eyes, with less than 10 DA and 10 DA or more of RNP at baseline (+17.5 vs. +0.8 letters and +18.3 vs. -4.1 letters, respectively) and with and without baseline MNP (+15.7 vs. +0.3 letters and +17.1 vs. +0.4 letters, respectively). Agreement between baseline RNP and MNP status was low (κ = 0.12). The proportions of patients with 1 or more ocular serious adverse event in the intravitreal aflibercept- and sham-treated groups, respectively, were 3.2% and 11.3%.

CONCLUSIONS

At W24, visual and anatomic improvements, including perfusion status, were greater in eyes treated with intravitreal aflibercept than in eyes treated with sham, regardless of baseline RNP or MNP status.

Ozurdex for refractory macular edema secondary to diabetes, vein occlusion, uveitis and pseudophakia

OBJECTIVE

To analyze the functional and morphological effects of the intravitreal dexamethasone implant (Ozurdex, Allergan) on patients with macular edema secondary to retinal vein occlusion (RVO), diabetic retinopathy (DME), posterior noninfectious uveitis (NIU), or pseudophakic Irvine-Gass syndrome (IGS).

METHODS

144 charts were retrospectively reviewed; 100 eyes met inclusion criteria for analysis: at least one intravitreal dexamethasone implant injection, refractory to antivascular endothelial growth factor, and had ≥6 months of follow-up postinsertion. The primary outcome was the efficacy of the dexamethasone implant in reducing macular edema as measured by reduction in central retinal thickness (CRT). Secondary outcomes included visual acuity (VA), duration of treatment efficacy (measured by time to next treatment), and safety. The Wilcoxon signed-rank test was used to compare values from baseline, and Kaplan-Meier survival curves were used to analyze time to retreatment.

RESULTS

There were 28 patients with RVO, 30 with DME, 24 with posterior NIU, and 18 with IGS. VA improved from baseline to month 6 in all groups, but was not statistically significant. CRT improved in all 4 groups, and was statistically significant for DME (p = 0.008) and NIU (p = 0.05). At 3 months, 34 patients (41.5%) required retreatment; by month 6, 46 patients (56.1%) required retreatment. There was a large variation between the groups in number of patients requiring intraocular pressure (IOP)-lowering medications. Two patients needed IOP-lowering surgery. One patient developed endophthalmitis.

CONCLUSION

The use of intravitreal dexamethasone implants in patients with refractory retinal diseases is well tolerated and results in consistently improved anatomic outcomes, but the positive anatomic outcomes are not necessarily correlated to improvements in visual function. Patients who are treated earlier in the disease process will had better outcomes. This patient population were refractory to treatment and, therefore, have less-predictable functional outcomes.

Clinical efficacy evaluation of treatment of different degrees of retinal vein occlusion with ranibizumab combined with an argon ion laser

The aim of this study was to evaluate the clinical efficacy of an intravitreal injection of ranibizumab combined with argon ion laser photocoagulation therapy in the treatment of different degrees of central retinal vein occlusion (CRVO). A total of 112 CRVO patients including 25 cases of trunk occlusion, 50 cases of branch occlusion and 37 cases of hemiretinal vein-occlusion were enrolled in this study. Patients were treated with an intravitreal injection of 0.5 mg ranibizumab, followed by argon ion laser photocoagulation therapy after 7 days. Patients were followed up for 6 months and the best corrected visual acuity (BCVA), central retinal thickness (CRT), macular edema, and surgical complications were compared. Compared with the control treated with 0.5 mg ranibizumab, the BCVA and macular edema improved while CRT was significantly reduced in all groups treated with 0.5 mg ranibizumab combined with the argon ion laser. Furthermore, no obvious complications were observed in these groups and the effects of ranibizumab combined with argon ion laser photocoagulation on branch occlusion group were the best. Intravitreal injection of ranibizumab combined with argon ion laser photocoagulation therapy has better safety and effectiveness in the treatment of different degrees of CRVO. The trial registration number is 2015–318 and date of registration is 12/10/2015.

Real-World Outcomes of Anti-VEGF Treatment for Retinal Vein Occlusion in Portugal

PURPOSE

Retinal vein occlusion (RVO) is an important cause of visual disability in the modern world. We aim to evaluate the real-world outcomes of patients with RVO treated with anti-vascular endothelial growth factor (VEGF) in Portugal.

METHODS

We performed a retrospective, observational, multicenter study including 8 centers across Portugal and 200 patients treated with either ranibizumab or bevacizumab. Data were collected at 3 time points: time of diagnosis (0 time point) and 6 and 12 months after initiating treatment. Demographic and clinical data were collected.

RESULTS

Median visual acuity (VA) and central macular thickness (CMT) improved in the branch RVO (BRVO), central RVO (CRVO), bevacizumab, and ranibizumab groups at 6 and 12 months compared to baseline, with CMT improving further only in the CRVO and ranibizumab groups between 6 and 12 months (p = 0.002 and p = 0.001, respectively). The CMT was lower in the ranibizumab group compared to the bevacizumab group both at 6 and 12 months (p<0.02). Median CMT improved in both the good and poor baseline VA groups at 6 and 12 months compared to baseline (p<0.001). Median VA only improved for the group with poor baseline VA at 6 and 12 months of follow-up (p<0.001). Regression analysis identified several baseline variables as predictors of visual outcomes at 6 and 12 months, with different results depending on the analyzed group.

CONCLUSIONS

Both treatments were effective, although less effective than results reported in clinical trials. The morphologic response was better with ranibizumab compared to bevacizumab, although functionally there were no differences.

Intravitreal bevacizumab upregulates transthyretin in experimental branch retinal vein occlusion

Purpose

To identify retinal protein changes that mediate beneficial effects of intravitreal bevacizumab in experimental branch retinal vein occlusion (BRVO).

Methods

In six Danish Landrace pigs, BRVO was induced with argon laser in both eyes. After BRVO was induced, the right eye of each animal was given an intravitreal injection of bevacizumab while the left eye was treated with saline water. The retinas were collected 15 days after BRVO, and differentially expressed proteins were analyzed with tandem mass tags-based mass spectrometry. Validation of statistically significantly changed proteins was performed with immunohistochemistry and western blotting.

Results

Fluorescein angiography showed no recanalization of the occluded vessels. A total of 4,013 proteins were successfully identified and quantified. Nine proteins were statistically significantly changed following bevacizumab intervention. In experimental BRVO, bevacizumab treatment resulted in upregulation of transthyretin (TTR) and pantothenate kinase 3. Bevacizumab downregulated protocadherin 7, protein FAM192A, and ATP synthase protein 8. Immunohistochemistry revealed that TTR was highly abundant in the choroid following bevacizumab intervention.

Conclusions

Bevacizumab intervention in experimental BRVO resulted in an increased level of TTR. This is the second study in which we showed an increased retinal level of TTR following anti-vascular endothelial growth factor (VEGF) intervention in experimental BRVO. We hypothesize that there is an interaction between TTR and VEGF and that bevacizumab may exert a beneficial effect on the retina by upregulating TTR.

IL-18 and S100A12 Are Upregulated in Experimental Central Retinal Vein Occlusion

Retinal vein occlusion (RVO) is a common retinal vascular disease. RVO may be complicated by pronounced ischemia that often leads to severe loss of visual function. The present work aimed at studying the retinal proteome of RVO complicated by ischemia. In six Danish Landrace pigs RVO was induced with argon laser in the right eye of each animal. As four retinal veins were occluded, the RVO best corresponded to a central retinal vein occlusion (CRVO). Left control eyes received a similar laser treatment without inducing occlusion. RVO and retinal ischemia were verified by angiography. The retinas were collected 15 days after RVO for proteomic analysis. RVO resulted in a downregulation of proteins involved in visual perception, including rhodopsin, transducin alpha chain, and peripherin-2. RVO also caused a downregulation of proteins involved in neurotransmitter transport, including glutamate decarboxylase 1 (GAD1), glutamate decarboxylase 2 (GAD2), and complexins 2⁻4. RVO lead to increased contents of proteins involved in inflammation, including interleukin-18 (IL-18), S100A12, and annexin A1 (ANXA1). Immunohistochemistry revealed a general retinal upregulation of IL-18 and ANXA1 while S100A12 was highly abundant in retinal ganglion cells in RVO. IL-18 and S100A12 are likely to be driving forces in the inflammatory response of RVO complicated by ischemia. Our findings also suggest that RVO results in compromised neurotransmission and a downregulation of proteins involved in visual perception.

Factor V G1691A is associated with an increased risk of retinal vein occlusion: a meta-analysis

We performed a meta-analysis to investigate the association between the Factor V G1691A polymorphism and the risk of retinal vein occlusion (RVO). This analysis included 37 studies involving 2,510 cases and 3,466 controls. Factor V G1691A was associated with an increased risk of RVO in the allele, heterozygote, dominant, and carrier models (PA < 0.001, odds ratios >1), but not the homozygote or recessive models (PA > 0.05). Similar results were observed in a meta-analysis of central retinal vein occlusion (CRVO) and when comparing Caucasian subgroups to population-based controls. These data demonstrate that the G/A genotype of Factor V G1691A is associated with an increased risk of RVO/CRVO in a Caucasian population.

Outcomes of switching treatment to aflibercept in patients with macular oedema secondary to central retinal vein occlusion refractory to ranibizumab

PURPOSE

To assess the treatment outcome of switching from ranibizumab to aflibercept intravitreal injections in patients with macular oedema secondary to central retinal vein occlusion (CRVO).

METHODS

A prospective interventional study was conducted in a tertiary retina service in Leicester Royal Infirmary, UK, where patients with CRVO and associated macular oedema were recruited. First-line treatment involved three monthly ranibizumab injections. Non-responders were defined as patients who despite a minimum of three consecutive injections had persistent intraretinal fluid one month after the last injection. In these cases, a treatment change to aflibercept injections on a per-needed basis was decided. Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were measured before and after switching of treatment. Follow-up period lasted for a minimum of 24 weeks after switching.

RESULTS

Twenty-nine eyes of 29 patients with refractory macular oedema secondary to CRVO were included. All eyes had an average of 4.5 ranibizumab intravitreal injections in a mean period of 6 months without reduction in intraretinal fluid and/or no visual acuity gain. A significant decrease in mean CRT from 633.67 ± 242.42 to 234.62 ± 78.28 μm and improvement in mean BCVA from 1.34 ± 0.66 log MAR to 0.91 ± 0.73 log MAR were noticed after switching treatment to aflibercept. The average number of aflibercept injections needed for oedema resolution was 2.19.

CONCLUSIONS

Aflibercept is an effective alternative treatment for macular oedema secondary to CRVO refractory to ranibizumab. Good anatomical and functional result can be achieved with few injections. The maintenance of these results after 6 months is yet to be investigated.

Comparison between "early" or "late" intravitreal injection of dexamethasone implant in branch (BRVO) or central (CRVO) retinal vein occlusion: six-months follow-up

AIM

The aim of this study was to compare early and late injections of intravitreal dexamethasone implant in patients affected by central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO) with a six-months follow-up. We assessed whether an earlier treatment start (within seven days from diagnosis) could be more beneficial than a delayed (or late) treatment start (after seven days).

MATERIALS AND METHODS

The study included 81 patients (81 eyes) affected by retinal vein occlusion. Best corrected visual acuity was assessed through Early Treatment Diabetic Retinopathy Study (ETDRS) while central macular thickness (CMT) was measured by spectral-domain optical coherence tomography.

RESULTS

Both types of patients had a positive therapeutic response to dexamethasone, with an increase in visual acuity (ETDRS) and CMT reduction. CRVO patients were characterized by lower ETDRS values at baseline and at the end of the follow-up as compared to BRVO. CRVO patients showed higher CMT values at baseline, after three and six months from injection. No significant differences in therapeutic response to dexamethasone were observed between patients treated early or late, regardless of RVO type.

CONCLUSIONS

This study demonstrates that the therapeutic properties of dexamethasone implant are not significantly influenced by an early or late treatment start in patients affected by BRVO and CRVO, although its therapeutic efficacy seems greater in the former type.