BRANCH RETINAL VEIN OCCLUSION: Epidemiology, Pathogenesis, Risk Factors, Clinical Features, Diagnosis, and Complications. An Update of the Literature

The Role of Serum Inflammation-Based Factors in Anti-Vascular Endothelial Growth Factor Treatment for Macular Edema Secondary to Retinal Vein Occlusion and Its Subtypes

OBJECTIVE

The aim of this work was to evaluate the association between pretreatment inflammation-based factors and outcomes in patients with macular edema (ME) secondary to retinal vein occlusion (RVO) and its subtypes after intravitreal ranibizumab or conbercept implant.

METHODS

This retrospective observational study included patients who were diagnosed with ME secondary to RVO at the First Affiliated Hospital of Nanchang University between January 2017 and January 2019, and who subsequently received intravitreal anti-vascular endothelial growth factor (VEGF) treatment. Blood-based parameters were measured before treatment, and correlations between best-corrected visual acuity (BCVA) and each of 3 parameters - neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) - were analyzed to identify predictors of effective intravitreal injection treatment outcomes.

RESULTS

A total of 315 treatment-naïve eyes treated with anti-VEGF drugs for RVO-ME were retrospectively analyzed in this study. The mean PLR value was significantly different in the effective and ineffective group for RVO-ME (138.03 ± 48.61 vs. 106.79 ± 27.28), branch RVO (BRVO)-ME (216.47 ± 53.04 vs. 185.94 ± 51.47), and central RVO (CRVO)-ME (231.07 ± 66.05 vs. 196.20 ± 60.44). The cutoff value of the PLR was 97.92, the area under the curve was 0.70, and the sensitivity and specificity were 81.5 and 44.3%, respectively. The mean NLR value was significantly different in the effective and ineffective groups for RVO-ME (2.20 ± 1.40 vs. 1.92 ± 0.89), and BRVO-ME (2.01 ± 0.80 vs. 1.82 ± 0.84), but not in patients with CRVO-ME (2.51 ± 2.02 vs. 2.12 ± 0.95). There are no significant differences between BRVO-ME and its subtype groups in MLR values. But the mean MLR value was significantly higher in the conbercept group than in the ranibizu-mab group among patients in the effective group (0.27 ± 0.11 vs. 0.25 ± 0.14).

CONCLUSION

Higher pretreatment PLR was associated with BCVA in patients with RVO-ME and its subtypes who were treated with anti-VEGF drugs. The PLR may be used as a predictive and prognostic tool for effective intravitreal injection treatment outcomes.

Altered intrinsic functional connectivity of the primary visual cortex in patients with retinal vein occlusion: a resting-state fMRI study

Background

To investigate the differences of spontaneous functional connectivity (FC) of the primary visual cortex (V1) between patients with retinal vein occlusion (RVO) and healthy controls (HCs) using resting-state functional magnetic resonance imaging (rs-fMRI) data.

Methods

Twenty-one patients with RVO in total (11 males, 10 females) and 21 HCs similarly analogue in age and sex background were enrolled and inspected with rs-fMRI. The difference in FC of V1 between two groups were compared using two-sample t-test. We used the receiver operating characteristic (ROC) curve to distinguish average FC values of RVO subjects from HCs. The interrelationships between FC signals of specific cerebrum regions and clinical features in RVOs were assessed with the Pearson's correlation analysis.

Results

Compared with HCs, FC in left V1 and right middle frontal gyrus increased significantly in RVO group, while FC in left V1 and right cuneus decreased significantly. Meanwhile, patients with RVO presented increased FC between the right V1 and right middle frontal gyrus, right superior frontal gyrus, but declining FC between right V1 and right cuneus. The mean FC value between the right cuneus and the right V1 as well as the left V1 were negative correlated with the foveal thickness of RVO patients. ROC curve analysis of each brain regions showed the accuracy of AUC was excellent.

Conclusions

RVO involves aberrant FC in V1 in different brain areas including visual-related and cognitive-related region, which might assist to unveil the underlying neural mechanisms of impaired visual function in RVO.

Evaluation of microvascular network with optical coherence tomography angiography (OCTA) in branch retinal vein occlusion (BRVO)

Background

To evaluate changes of microvascular network of macular and peripapillary regions and to provide a quantitative measurement of foveal avascular zone (FAZ) in unilateral BRVO patients.

Methods

Forty-seven unilateral BRVO patients and forty-seven normal controls were enrolled. A 3*3 mm scan centered on fovea followed by a 4.5*4.5 mm scan centered on optic nerve head (ONH) were obtained in BRVO eyes, fellow eyes and control eyes of each individual using OCTA (Optovue Inc., Fremont, CA, USA). Vessel density (VD) in superficial (SVC) and deep vascular complex (DVC) of macula and radial peripapillary capillary (RPC) were automatically calculated. Parameters of FAZ region including size, perimeter, acircularity index (AI) and foveal vessel density 300 (FD-300) were measured.

Results

VDs of SCV and DVC were significantly lower, especially in affected regions, in BRVO eyes compared with fellow eyes (P < 0.05). BRVO affected eyes has larger FAZ size, FAZ perimeter, AI and lower FD-300 compared with fellow eyes (all P < 0.05). VD of SVC and FD-300 were lower in fellow eyes compared with normal control eyes (P < 0.05). The average vessel density in whole area and peripapillary area in BRVO eyes were significantly lower compared with fellow eyes (P < 0.05). VD of inside disc in fellow eyes was lower than normal eyes (P < 0.05).

Conclusions

OCTA provided quantitative information of vascular changes in BRVO. FAZ in BRVO eyes showed significant morphological alterations and decreases of VD in surrounding area. Decreases of VD existed not only in SVC and DVC in macular region but also in RPCs in BRVO eyes. Unaffected eyes of unilateral BRVO showed vascular abnormalities in superficial retinal layer, peri-FAZ area and also peripapillary regions.

Longitudinal Changes in Retinal Blood Flow in a Feline Retinal Vein Occlusion Model as Measured by Doppler Optical Coherence Tomography and Optical Coherence Tomography Angiography

Purpose

We aimed to observe longitudinal changes in retinal blood flow (RBF) and structural transformations in capillaries using Doppler optical coherence tomography (DOCT) and optical coherence tomography angiography (OCTA) in a feline retinal blood occlusion (RVO) model.

Methods

RVO was induced by argon green laser photocoagulation (PC) in six eyes of six cats. RBF was measured at a first-order retinal artery and vein by a DOCT flowmeter, and structural changes in the capillaries around the occluded vessels (12 × 12 and 3 × 3 mm) were assessed by OCTA before (at baseline); immediately after PC; and on days 1, 4, 7, and 14 thereafter. Systemic and ocular parameters were monitored during the observation period.

Results

There were no significant differences in any systemic or ocular parameters before and after PC. Arterial RBF increased significantly on day 1 (160.6 ± 8.6% vs. baseline, P < 0.001) and decreased below baseline after day 1 through 14. Venous RBF decreased immediately after PC (17.4 ± 9.6% vs. baseline, P = 0.001) and then gradually increased afterwards, but did not return to baseline. OCTA showed dilatation of retinal venules immediately after PC to day 1. Collateral vessels began to form on day 4, had matured by day 7, and were pruned on day 14, which formed as mature as normal retinal venule diameters.

Conclusions

With increasing arterial RBF within 1 day after inducing RVO, venules gradually expanded to form collateral vessels, suggesting that collateral vessels originate from existing capillary networks, not neovascularization.

Intravitreal injection of conbercept combined with retinal photocoagulation on macular edema secondary to branch retinal vein occlusion

Effects of Conbercept combined with retinal photocoagulation on macular edema secondary to branch retinal vein occlusion (BRVO) were investigated. A total of 98 patients (98 eyes) with macular edema secondary to BRVO were collected. The central macular thickness (CMT), incidence rate of complications after treatment and best corrected visual acuity (BCVA) were recorded. Also the factors affecting visual recovery of patients were analyzed. At 1 week, 1 month, 3 months and 6 months after treatment, the BCVA in both groups was significantly superior to that before treatment (P<0.05). In the combination group and laser group, the logarithm of the minimum angle of resolution (logMAR) of BCVA increased from 0.84±0.47 to 0.34±0.10 and from 0.89±0.49 to 0.45±0.14, and CMT declined from 559.5±152.7 to 267.8±19.8 µm and from 570.3±172.6 to 314.7±18.4 µm. It was observed that at 1 week, 1 month, 3 months and 6 months after treatment, the BCVA in combination group was obviously better than that in laser group (P=0.008, P<0.001, P=0.004, P<0.001, respectively), while CMT in combination group was obviously smaller than that in laser group (P=0.009, P=0.002, P<0.001, P<0.001). Conbercept with retinal photocoagulation can effectively improve the visual acuity and reduce the CMT. The visual recovery of patients after treatment is related to the BCVA before treatment, decreased value of CMT at 1 month after treatment and integrity of external limiting membrane (ELM).

Focal lamina cribrosa defects and significant peripapillary choroidal thinning in patients with unilateral branch retinal vein occlusion

Purpose

To investigate the prevalence of focal lamina cribrosa (LC) defects in patients with unilateral branch retinal vein occlusion (BRVO) and to compare ocular characteristics between eyes with and without focal LC defect and those eyes with normal-tension glaucoma (NTG).

Methods

This retrospective, cross-sectional study included 121 patients. Thirty-nine patients had unilateral BRVO (BRVO group), 36 patients had NTG (NTG group), and 36 patients had vitreous floaters, but no other ocular diseases (control group). In addition to baseline characteristics such as age, sex, refractive errors, the ocular characteristics such as peripapillary choroidal thickness (PCT), retinal nerve fiber layer thickness, and subfoveal choroidal thickness were retrospectively analyzed.

Results

Focal LC defects were detected in 20 eyes of 14 patients (38.9%) in the BRVO group, 24 eyes of 15 patients (41.7%) in the NTG group, and none in the control group (P<0.001). In the BRVO-affected eyes, the mean PCT was 102.7±31.1 μm in the eyes with focal LC defects, and 163.1±70.1 μm in the eyes without LC defects (P = 0.009). In the BRVO-affected eyes, the mean PCT was 102.7±31.1 μm in the eyes with focal LC defects, and 163.1±70.1 μm in the eyes without LC defects (P = 0.009). In the NTG group, the mean PCT was 133.1±48.9 μm in the eyes with focal LC defects and 170.8±81.9 μm in those without (P = 0.042). The other baseline and ocular characteristics were not significantly different between the eyes with and without focal LC defects in both the BRVO group and the NTG group.

Conclusions

About 40% of the patients with unilateral BRVO had focal LC defect in the BRVO-affected eyes and unaffected fellow eyes, similar prevalence to the patients with NTG. The mean PCT was significantly thinner in the eyes with focal LC defect than those without in the patients with BRVO and those with NTG, suggesting possible pathophysiologic correlation between these two diseases.

One-year efficacy of intravitreal conbercept injection for macular oedema secondary to central retinal vein occlusion in Chinese patients

PURPOSE

To evaluate intravitreal conbercept injection for treatment of macular oedema secondary to central retinal vein occlusion (CRVO) in Chinese patients during 1-year follow-up in the real-world setting.

METHODS

Twenty-seven eyes of 27 patients with macular oedema associated with CRVO were retrospectively reviewed. The eyes received monthly intravitreal conbercept injection (0.5 mg in 50 µl) for 3 months. From then on, the patients were followed up every month and received injection pro re nata (PRN) up to 12 months. The primary outcome measurements included changes of best-corrected visual acuity (BCVA) and central retinal thickness (CRT) from baseline to month 3 and month 12. Other outcome measurements included proportion of patients gaining ≥15 letters in BCVA at month 3 and 12, the mean number of injections and safety concerns.

RESULTS

The mean BCVA gain from baseline was 12.7 ± 7.6 letters at month 3 and 14.8 ± 9.6 letters at month 12. The mean CRT reduction from baseline was 374.5 ± 280.7 μm at month 3 and 428.2 ± 241.3 μm at month 12. The proportion of patients who gained ≥15 letters in BCVA was 45.1% at month 3 and 52.9% at month 12. The mean number of injections was 7.6 ± 1.5. No severe local and systemic complications occurred following injection.

CONCLUSIONS

Intravitreal conbercept injection by three monthly loading doses followed by PRN treatment regimen was safe and efficacious for patients with macular oedema secondary to CRVO through 1-year follow-up.

Prevalence of resolved paracentral acute middle maculopathy lesions in fellow eyes of patients with unilateral retinal vein occlusion

PURPOSE

To study the prevalence of resolved paracentral acute middle maculopathy (PAMM) lesions in fellow eyes of patients with unilateral retinal vein occlusion (RVO) and eyes of healthy individuals.

METHODS

This case-control observational study took place in a referral university medical centre. Forty-five (17 males, 28 females, 64.7 ± 10.8 years) patients with branch retinal vein occlusion (BRVO), 21 (17 males, 4 females, 68.8 ± 11.2 years) patients with central retinal vein occlusion (CRVO) and 57 healthy individuals (25 males, 32 females, 67.4 ± 10.5 years) were included. Presence of resolved PAMM lesions was evaluated by reviewing cross-sectional scans of 8-mm optical coherence tomography angiography protocol. Resolved PAMM lesion was defined as inner nuclear layer thinning with outer plexiform layer elevation.

RESULTS

Resolved PAMM lesions were found in 32/45 (71.1%) and 15/21 (71.4%) of BRVO and CRVO patients, respectively. In healthy volunteers, resolved PAMM lesions were found in 11/57 (19.3%) individuals with bilateral involvement in 8 individuals (72.7%). RVO patients demonstrated the presence of resolved PAMM lesions in fellow eye significantly more frequently than healthy individuals (odds ratio (OR) 10.6, p < 0.001, 95% CI 4.5-24.6). OR for the presence of large resolved PAMM lesions in BRVO patients and CRVO patients versus healthy individual was 12.1 (p = 0.02, 95% CI 1.5-100.9) and 22.4 (p = 0.005, 95% CI 2.5-200.6), respectively.

CONCLUSION

Resolved PAMM lesions defined as inner nuclear layer thinning associated with outer plexiform layer elevation are highly prevalent in fellow eyes of patients with unilateral RVO. Resolved PAMM lesions may have an association with RVO.

RELATIONSHIP BETWEEN ABNORMALITIES OF PHOTORECEPTOR MICROSTRUCTURES AND MICROVASCULAR STRUCTURES DETERMINED BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN EYES WITH BRANCH RETINAL VEIN OCCLUSION

PURPOSE

To determine whether the size of the foveal avascular zone (FAZ) is significantly correlated with the best-corrected visual acuity (BCVA) and to examine the relationship between the size and microstructural changes of the photoreceptors in eyes with a branch retinal vein occlusion.

METHODS

The medical records of 69 eyes of patients (mean age, 64.6 ± 11.7 years) with a branch retinal vein occlusion were reviewed after the resolution of macular edema. All the patients underwent optical coherence tomography angiography for measurement of the FAZ area and spectral domain optical coherence tomography for determination of microstructural changes of the photoreceptors at the fovea.

RESULTS

The superficial and deep FAZ areas in eyes with a branch retinal vein occlusion were 0.39 ± 0.36 mm and 0.63 ± 0.18 mm, respectively, and both were significantly larger than those observed in the fellow eyes (both, P < 0.001). The superficial FAZ area correlated with the posttreatment BCVA (r = 0.285, P = 0.027) but not with any parameters regarding the microstructures of the photoreceptors. Multivariate linear regression analysis showed that the pretreatment BCVA (β = 0.519, P < 0.001) and integrity of the external limiting membrane (β = -0.373, P = 0.001) were independent factors that significantly correlated with the posttreatment BCVA.

CONCLUSION

There was no significant correlation between the FAZ area and microstructural parameters. However, the integrity of the external limiting membrane was significantly correlated with the posttreatment BCVA in eyes with a branch retinal vein occlusion.

Ocular blood flow as a clinical observation: Value, limitations and data analysis

Alterations in ocular blood flow have been identified as important risk factors for the onset and progression of numerous diseases of the eye. In particular, several population-based and longitudinal-based studies have provided compelling evidence of hemodynamic biomarkers as independent risk factors for ocular disease throughout several different geographic regions. Despite this evidence, the relative contribution of blood flow to ocular physiology and pathology in synergy with other risk factors and comorbidities (e.g., age, gender, race, diabetes and hypertension) remains uncertain. There is currently no gold standard for assessing all relevant vascular beds in the eye, and the heterogeneous vascular biomarkers derived from multiple ocular imaging technologies are non-interchangeable and difficult to interpret as a whole. As a result of these disease complexities and imaging limitations, standard statistical methods often yield inconsistent results across studies and are unable to quantify or explain a patient's overall risk for ocular disease. Combining mathematical modeling with artificial intelligence holds great promise for advancing data analysis in ophthalmology and enabling individualized risk assessment from diverse, multi-input clinical and demographic biomarkers. Mechanism-driven mathematical modeling makes virtual laboratories available to investigate pathogenic mechanisms, advance diagnostic ability and improve disease management. Artificial intelligence provides a novel method for utilizing a vast amount of data from a wide range of patient types to diagnose and monitor ocular disease. This article reviews the state of the art and major unanswered questions related to ocular vascular anatomy and physiology, ocular imaging techniques, clinical findings in glaucoma and other eye diseases, and mechanistic modeling predictions, while laying a path for integrating clinical observations with mathematical models and artificial intelligence. Viable alternatives for integrated data analysis are proposed that aim to overcome the limitations of standard statistical approaches and enable individually tailored precision medicine in ophthalmology.

Altered Intrinsic Functional Connectivity of the Primary Visual Cortex in Patients with Neovascular Glaucoma: A Resting-State Functional Magnetic Resonance Imaging Study

PURPOSE

The purpose was to investigate the differences in spontaneous functional connectivity (FC) of the primary visual cortex (V1) between patients with neovascular glaucoma (NVG) and healthy controls (HCs) using resting-state functional magnetic resonance imaging data.

METHODS

A total of 18 patients with NVG (nine males and nine females) and 18 HCs with similar age and sex background were enrolled in the study and inspected using resting-state functional magnetic resonance imaging. The differences in FC of the V1 between the two groups were compared using the independent samples t-test. We used the receiver operating characteristic (ROC) curve to compare the average FC values of NVG subjects with those of HCs.

RESULTS

FC in the left V1 and right fusiform gyrus, bilateral cuneus, and left precuneus was significantly decreased in the NVG group compared with that reported in the HC group. Meanwhile, patients with NVG presented increased FC between the right V1 and bilateral middle frontal gyrus. However, they also exhibited declining FC between the right V1 and left precuneus, and bilateral cuneus. The ROC curve analysis of each brain region indicated that the accuracy of the area under the ROC curves regarding NVG was excellent.

CONCLUSION

NVG involves aberrant FC in the V1 in different brain areas, including the visual-related and cognitive-related regions. These findings may assist in unveiling the underlying neural mechanisms of impaired visual function in NVG.

Effects of Switching to Aflibercept in Treatment Resistant Macular Edema Secondary to Retinal Vein Occlusion

PURPOSE

The aim of this study was to examine 12-month outcomes of eyes switched from intravitreal ranibizumab or bevacizumab to aflibercept for cystoid macular edema due to retinal vein occlusion (RVO).

DESIGN

Retrospective, observation, case series.

METHODS

A retrospective study was performed assessing eyes with RVO switched to aflibercept for at least 12 months. To be included in the study, eyes had to have macular edema despite treatment for at least 6 months with bevacizumab and/or ranibizumab before the switch, central foveal thickness (CFT) ≥300 μm at time of switch, and visual acuity (VA) ≤60 early treatment of diabetic retinopathy score (ETDRS) letters (20/40 Snellen equivalent). Outcome measures included change in VA (in ETDRS letters), CFT, and interval between intravitreal injections.

RESULTS

27 eyes of 27 patients were included in the analysis: 13 with branch RVO, and 14 with central RVO. Mean VA before switch was 54.2 ± 23.7 letters (20/80 Snellen equivalent) and mean CFT was 460.4 ± 178.2 μm. Mean number of previous anti-vascular endothelial growth factor (VEGF) injections was 29.5 ± 19.2. At 12 months, mean VA improved by 8.7 ± 13.2 letters (P < 0.01) and mean CFT decreased by 180.9 ± 207.7 μm compared with baseline (P < 0.01). Mean injection interval increased by 1.6 ± 2.0 weeks to 6.9 ± 1.2 weeks, but this was not statistically significant (P = 0.18).

CONCLUSIONS

In our small retrospective study, eyes switched to intravitreal aflibercept for persistent cystoid macular edema (CME) due to RVO improved vision and macular thickness; however, larger prospective studies are required to validate our findings.

Wide-field angiography in retinal vein occlusions

Background

Retinal vein occlusion (RVO) is the second most common retinal vascular disease after diabetic retinopathy. It can result in significant visual loss from complications like macula edema, retinal and iris neovascularization, and vitreous hemorrhage. Recently, ultra-widefield imaging (UWF) has been developed for posterior pole visualization and has shown to be useful in the evaluation and treatment of RVO.

Main text

Ultra-widefield imaging (UWF) imaging allows for visualization of the retina up to an angle of 200°. This is especially important in detecting peripheral retinal pathologies, especially in retinal conditions such as RVO, where the disease process affects the peripheral as well as central retina. In particular, retinal non-perfusion in RVO is a risk factor for neovascularization. Various techniques, such as ischemic index and stereographic projection, have been described to assess areas of ischemia on UWF images. Retinal non-perfusion has an impact on disease complications, such as macular edema, and retinal and iris neovascularization. Retinal non-perfusion also has implications on disease response, including visual acuity, reduction in retinal edema and treatment burden.

Conclusion

Ultra-widefield imaging (UWF) imaging plays an important role in the assessment and management of RVO, especially in measuring retinal non-perfusion in the peripheries.

Thickness of the Lamina Cribrosa, Retinal-Nerve Fiber Layer, and Peripapillary Choroid in Patients with Branch Retinal Vein Occlusion

PURPOSE

To compare the thickness of the lamina cribrosa (LC), retinal-nerve fiber layer (RNFL), and peripapillary choroid (PC) in patients with unilateral branch retinal-vein occlusion (BRVO) and healthy individuals.

METHODS

The 70 eyes of 35 patients with unilateral BRVO, grouped as either affected or unaffected, and 38 right eyes of 38 healthy individuals were examined for LC, RNFL, PC thickness, and LC depth with spectral-domain optical coherence tomography.

RESULTS

The unaffected eyes of patients with BRVO had a significantly thinner RNFL on average and in the inferior quadrant than the eyes of healthy controls. Mean LC thickness in BRVO-affected and BRVO-unaffected eyes was significantly thinner than in controls, and mean LC depth was significantly deeper as well. The average, superior, and inferior PC thickness in both BRVO-affected and BRVO-unaffected eyes and nasal PC thickness in the BRVO-affected eyes were significantly thinner than in the eyes of controls.

CONCLUSION

Thinner LCs and PCs in both eyes of patients with unilateral BRVO and thinner RNFLs in BRVO-unaffected eyes than in the eyes of healthy controls suggest that BRVO and glaucoma have underlying pathological mechanisms and risk factors in common that lead to their development.

Comparison of Ranibizumab versus Aflibercept in Treating Macular Edema among Patients with Serous Retinal Detachment Secondary to Branch Retinal Vein Occlusion

Purpose: To compare the effectiveness of ranibizumab and aflibercept in macular edema (ME) with serous retinal detachment (SRD) following branch retinal vein occlusion (BRVO).Methods: Once every month for 3 months, 33 patients were treated with ranibizumab (Group 1), whereas 30 others were treated with aflibercept (Group 2). In 9 months after that, patients were evaluated every 4 weeks and received additional injections if they met prespecified criteria for retreatment. Corrected visual acuity (BCVA), central foveal thickness (CFT), and height of SRD was measured.Results: During the first 3 months, the improvement of CFT, BCVA, and height of SRD were greater in Group 2 than Group 1. Those differences disappeared in the subsequent 9 months, and changes in CFT, BCVA, and height of SRD were similar between groups at all other visits.Conclusion: Aflibercept was more effective than ranibizumab from baseline to Month 3 in ME with SRD following BRVO.

Papillary Vessel Density Changes After Intravitreal Anti-VEGF Injections in Hypertensive Patients with Central Retinal Vein Occlusion: An Angio-OCT Study

Purpose: To investigate papillary microvascular changes in patients affected by macular edema due to Central Retinal Vein Occlusions (CRVO) after anti-Vascular Endothelial Growth Factor (VEGF) therapy. Methods: Prospective analysis of papillary and peripapillary vessel density (VD) changes in 18 eyes of 18 hypertensive patients affected by CRVO before and after the loading-phase of intravitreal Ranibizumab (IVR) injections. Data were quantitatively measured by optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) before as well as 1 month and 4 months after injections. The correlation between post-treatment best-corrected visual acuity (BCVA) and changes in the retinal microvasculature evaluated by OCTA was assessed. Results: 18 eyes of 18 consecutive patients with a known history of arterial hypertension and affected by an acute CRVO episode were enrolled. Central macular thickness (CMT) was significantly reduced after IVR injections (p < 0.001), while mean BCVA improved from 0.70 ± 0.26 logarithm of the minimal angle of resolution (logMAR) units at baseline to 0.25 ± 0.18 logMAR units after 4 months (p < 0.001). VD inside disc and peripapillary significantly increased (p < 0.001 and p = 0.01, respectively) after treatment. Conclusions: OCTA showed VD increase in the papillary area in patients affected by CRVO after anti-VEGF therapy. This area could represent a new region of interest to study microvasculature changes concomitant with severe macular edema.

OCT angiography features associated with macular edema recurrence after intravitreal bevacizumab treatment in branch retinal vein occlusion

We aimed to evaluate the relationship between the capillary abnormalities including nonperfusion area (NPA) in optical coherence tomography angiography (OCTA) images and the recurrence of macular edema (ME) secondary to branch retinal vein occlusion (BRVO) after intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF; bevacizumab). The records of 40 patients who underwent intravitreal bevacizumab injection for ME secondary to BRVO and had at least six months of follow-up were reviewed. Central retinal thickness (CRT; μm) and macular edema type were evaluated prior to treatment. After ME resolution, nonperfusion areas in the 1 mm (NPA1) and 1–3 mm (NPA3) zones on the Early Treatment Diabetic Retinopathy Study (ETDRS) circle within the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were measured using OCTA images. Furthermore, other microvascular abnormalities in the both SCP and DCP were compared between groups. ME recurred in 25 of 40 (62.5%) eyes. The NPA1 of the SCP and DCP (p = 0.002, 0.004, respectively), NPA3 of the SCP and DCP (p = 0.002, 0.008, respectively), and initial CRT (p = 0.022) differed significantly between eyes with and without ME recurrence. In multivariate logistic regression analyses, the NPA1 of the DCP (OR: 344.718; p = 0.029) and NPA3 of the SCP (OR: 4.072; p = 0.018) were significantly associated with ME recurrence. Other microvascular abnormalities were not significantly different between two groups. The central NPA and parafoveal NPA of the SCP in OCTA images correlated strongly with ME recurrence in BRVO patients after intravitreal anti-VEGF injection.

Mapping research trends of retinal vein occlusion from 2009 to 2018: a bibliometric analysis

Objectives

To map publication trends and explore research hotspots of retinal vein occlusion (RVO) study.

Methods

Based on Web of Science Core Collection (WoSCC), a bibliometric analysis was carried out. The knowledge map was constructed by VOSviewer v.1.6.10 to visualize the annual publication number, the distribution of countries, international collaborations, author productivity, source journals, cited reference and keywords in this field.

Results

A total of 2,135 peer-reviewed papers were retrieved on RVO from 2009 to 2018. The United States ranks highest among countries with the most publications and the most active institution was Kyoto University. Noma H contributed the most publications in this field. Retina-The Journal of Retinal and Vitreous Disease was the most prolific journal in RVO research. The top cited references mainly presented anti-VEGF medications on the management of RVO. The keywords formed six clusters: (1) Risk factors and pathogenesis of RVO; (2) Metabolismof RVO; (3) Therapeutic use of corticosteroids on RVO; (4) Diagnostic methodsof RVO; (5) Management of macular edema secondary to RVO (6) Anti-VEGFtreatment of RVO.

Conclusions

The six major research hotspots could provide an insight into RVO research and valuable information for researchers to identify potential collaborators and partner institutions.

Arteriovenous crossing associated with branch retinal vein occlusion

Branch retinal vein occlusion (BRVO) is defined as the focal occlusion of a first or second-order branch of retinal vein, which occurs most frequently at an arteriovenous (AV) crossing. Direct ophthalmoscopy, color fundus photography, and fluorescein angiography facilitate observation of AV crossings parallel to the retinal plane. Optical coherence tomography (OCT), with its high-depth resolution, enables observation of retinal lesions perpendicular to the retinal plane. OCT angiography (OCTA) provides depth-resolved images of the retinal vasculature by segmenting three-dimensional data. In this review, we discuss novel findings related to affected AV crossings associated with BRVO obtained via OCT and OCTA. The high-depth resolution of OCT or OCTA is useful for observation of the narrowed vein and determination of the vessel position of the affected AV crossing. Studies using OCT and OCTA have shown that BRVO caused by a venous overcrossing is more prevalent than previously reported, and that venous narrowing was significantly greater in instances caused by a venous overcrossing than in those caused by an arterial overcrossing. Moreover, OCTA also revealed that the retinal nonperfusion area size was larger in eyes with BRVO caused by a venous overcrossing than in those with BRVO caused by an arterial overcrossing. This contrasts with earlier findings obtained by conventional imaging modalities predating OCT, which showed that an arterial overcrossing was more common than a venous overcrossing at the causative venous occlusion site in eyes with BRVO. This review discusses these findings and their significance in the study of AV crossing associated with BRVO.

Comparison of systemic conditions at diagnosis between central retinal vein occlusion and branch retinal vein occlusion

Objective

To compare systemic conditions at the time of diagnosis between patients with central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO).

Design

This study included patients diagnosed with CRVO or BRVO between February 2009 and August 2017 at three branch hospitals of Hallym University Medical Center. Demographic and anthropometric variables, systemic comorbidity profiles, and laboratory findings at diagnosis were collected from a clinical data warehouse system, and were compared between the CRVO and BRVO groups.

Result

Four hundred and seventeen patients with CRVO and 1,511 patients with BRVO were included. The mean age was 61.8 ± 13.9 years, which was comparable between two groups (P = .332). Female proportion was higher in the BRVO group (55.0%) than in the CRVO group (48.0%; P = .013). Diabetes mellitus (P = .017) and chronic kidney disease (P = .004) were more prevalent in the CRVO group. Serum homocysteine level was abnormally high in 23.5% of CRVO patients and in 8.4% of BRVO patients (P < .001). Blood urea nitrogen and serum creatinine levels were abnormally elevated in more subjects with CRVO (P = .002).

Conclusion

CRVO is associated with higher prevalence of diabetes mellitus and chronic kidney disease, as well as with elevated serum homocysteine level. These results might suggest a difference between the pathophysiologies of CRVO and BRVO.

Comparison of Retinal Layer Thickness and Vascular Density between Acute and Chronic Branch Retinal Vein Occlusion

Purpose

To compare retinal layer thickness and chorioretinal vascular density (VD) between acute and chronic branch retinal vein occlusion (BRVO).

Methods

This study included patients with BRVO. The VD of the superficial capillary plexus (VDs), the VD of the deep capillary plexus (VDd), and VD of the choriocapillaris were obtained using optical coherence tomography angiography. Acute and chronic BRVO data were compared to assess differences between the involved and uninvolved areas.

Results

We included 17 eyes with acute BRVO and 23 eyes with chronic BRVO. The VDs in the involved area were not significantly different between the involved area and in the uninvolved area in acute BRVO (p = 0.551). However, the difference was significant in chronic BRVO (p = 0.013). The VDd in the involved area was lower than in the uninvolved area in both acute and chronic BRVO (p = 0.020, p = 0.003, respectively). In addition, the VD of the choriocapillaris values did not differ significantly between acute and chronic BRVO, or between involved and uninvolved areas. The VDs in the involved area in chronic BRVO were lower than in acute BRVO (p = 0.047), and the VDd did not differ between acute and chronic BRVO in all areas.

Conclusions

Vascular impaired patterns in the retinal layer differed between acute and chronic BRVO. These results may suggest that vascular change and remodeling develops differently in acute and chronic phases in BRVO.

Quantitative Analysis of Retinal Microvascular Changes after Conbercept Therapy in Branch Retinal Vein Occlusion Using Optical Coherence Tomography Angiography

PURPOSE

To quantitatively evaluate microvascular changes in eyes with macular oedema due to branch retinal vein occlusion (BRVO) using optical coherence tomography angiography (OCTA) before and after intravitreal conbercept injection and the correlation of such changes with best-corrected visual acuity (BCVA) and retinal thickness.

METHODS

Twenty-eight eyes of 28 patients treated with a single intravitreal injection of conbercept for macular oedema due to BRVO were included in this study. The automatically measured values of the vessel density in the superficial (SCP) and deep retinal capillary plexus (DCP), the foveal avascular zone (FAZ) area, the FAZ perimeter, the vessel density within a 300 μm wide ring surrounding the FAZ (FD-300), the acircularity index (AI), the choriocapillaris flow area and the retinal thickness were obtained via OCTA before and at 1 month after initial injection and compared with those of age- and sex- matched healthy subjects.

RESULTS

In BRVO eyes, the vascular density in the SCP and DCP, the FD-300 and the flow area of choriocapillaris were significantly lower than those in healthy eyes, while the AI and the retinal thickness were significantly increased. After treatment, the retinal thickness in eyes with BRVO was significantly decreased in all quadrants, and the mean BCVA dramatically increased from 20/162 to 20/78 (p = 0.0017). The mean flow area of choriocapillaris significantly improved after treatment. Moreover, negative correlations between the logMAR BCVA and the whole vascular density in the SCP and DCP as well as the flow area of choriocapillaris were observed.

CONCLUSION

OCTA enables non-invasive, layer-specific and quantitative assessment of microvascular changes in eyes with BRVO before and after treatment, and it can be used as a valuable imaging tool for the evaluation of the follow-up in BRVO patients.

Genetic polymorphisms associated with the prevalence of retinal vein occlusion in a Greek population

PURPOSE

To investigate possible associations of single-nucleotide polymorphisms (SNPs) from five genes with branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO).

METHODS

A total of 69 patients with retinal vein occlusion-RVO (24 with BRVO and 45 with CRVO), and 82 controls, were enrolled in this study. All subjects were screened for hypertension, diabetes mellitus, hyperlipidemia, glaucoma, anticoagulant medication, smoking status and history of stroke. The genotyping of AGTR1-A1166C, adiponectin + 276 G/T, MMP2-1306C/T, Gpla/lla-C807T/G873A and VKORC1-G1639A polymorphisms was performed using restriction fragment length polymorphism or allele-specific polymerase chain reaction.

RESULTS

The percentage of the AGTR1-A1166C C allele carriers and Gpla/lla-C807T/G873A T/A carriers was significantly higher in the CRVO patients than in the controls (P = 0.00001 and P = 0.0004, respectively). At the multiple logistic regression analysis, the AGTR1-A1166C C allele carrier status and the Gpla/lla-C807T/G873A T/A allele carrier status were found to be associated with an increased risk of CRVO. Moreover, adiponectin + 276 G/T T allele carriers had a significantly increased risk of RVO in subjects ≥ 75 years old. There was no significant difference between the BRVO patients and controls concerning the genotype or the allele frequency distributions of these SNPs. The genotype distributions or allelic frequencies of the other evaluated polymorphisms did not significantly differ between the patients with RVO and the control subjects.

CONCLUSIONS

AGTR1 A1166C and Gpla/lla C807T/G873A polymorphisms are likely to be risk factors for CRVO. Adiponectin + 276 G/T SNP is likely to predispose to RVO in older subjects.

Pyogenic Granuloma of the Retina: A Case Series

Aim

To describe the clinicopathologic features of pyogenic granuloma (granulation tissue proliferation) extending from the retina.

Methods

We describe 3 patients who underwent enucleation for endophthalmitis. The eyes were processed routinely for histopathologic examination.

Results

All 3 enucleated eyes contained granulation tissue with reactive vascular channels and intervening stroma infiltrated with inflammatory cells. The vascular channels were arranged in a fan-like configuration and the tissue was classified as representing pyogenic granulomas.

Conclusions

Pyogenic granulomas (granulation tissue) may emanate from the retina in cases of endophthalmitis. This is distinct from neovascularization that may occur in proliferative diabetic retinopathy, central retinal vein occlusion, or other etiologies.

Comparison of dexamethasone intravitreal implant with intravitreal anti-VEGF injections for the treatment of macular edema secondary to branch retinal vein occlusion: A meta-analysis

BACKGROUND

This meta-analysis compared the efficacy and safety of dexamethasone intravitreal implant (DEX) and anti-vascular endothelial growth factor (anti-VEGF) in the treatment of macular edema (ME) secondary to branch retinal vein occlusion (BRVO).

METHODS

The PubMed, Embase, Cochrane Library, and Web of Science databases were comprehensively searched for published studies comparing DEX with anti-VEGF for the treatment of ME caused by BRVO. Outcomes of the selected studies included best-corrected visual acuity (BCVA), central macular thickness (CMT), and adverse events. Review Manager (RevMan) 5.3 was used to analyze the data.

RESULTS

Six trials comparing the efficacy and safety of DEX with anti-VEGF were included in this meta-analysis. At 1 month, DEX achieved a mean BCVA superior to that achieved by anti-VEGF (MD = -0.11, P < .0001), in addition to a superior mean BCVA change (MD = -0.35, P < .00001). At 3 months, the mean BCVA showed a significant difference (MD = -0.06, P = .03) between DEX and anti-VEGF treatment, while the mean BCVA change was similar to that with anti-VEGF treatment (MD = -0.06, P = .11). However, neither mean BCVA nor mean BCVA change showed a significant difference between DEX and anti-VEGF treatment at 6 months (MD = 0.08, P = .06; MD = 0.06, P = .43, respectively). Mean CMT and mean CMT change were significantly lower in the DEX group than in the anti-VEGF group at 1 month (MD = -53.63 μm, P < .00001; MD = -60.1 μm, P = .005, respectively). However, at 3 months, mean CMT and mean CMT change were similar between DEX and anti-VEGF treatment (MD = 17.4 μ, P = .74; MD = 18.01 μm, P = .72, respectively). Although mean CMT in the anti-VEGF group was not significantly lower than that in the DEX group at 6 months (MD = 55.53, P = .07), the mean CMT change from baseline achieved by the anti-VEGF treatment was significantly superior to that obtained with DEX (MD = 75.53, P = .0002). Concerning adverse events, no statistically significant differences were observed in the incidence of cataract (OR = 4.25, P = .07), but the use of DEX led to a higher risk of intraocular pressure elevation compared with anti-VEGF treatment (OR = 12.04, P = .006).

CONCLUSIONS

Our results show that visual acuity recovery and CMT were better in the DEX group than in the anti-VEGF group after 1 and 3 months, although the difference in CMT at 3 months was not significant. However, there were no significant differences in terms of visual acuity and CMT between the two groups after 6 months of follow-up. Therefore, DEX may be recommended as the first treatment option in ME associated with BRVO.

Impact and Implication of Fovea-Involving Intraretinal Hemorrhage after Acute Branch Retinal Vein Occlusion

PURPOSE

To compare clinical outcomes in patients with branch retinal vein occlusion (BRVO) with (group A) or without (group B) fovea-involving intraretinal hemorrhage (IRH).

DESIGN

Retrospective cohort study.

PARTICIPANTS

All patients diagnosed with acute, treatment-naive BRVO seen by the Duke Eye Center Retina Service from January 1, 2009, through June 30, 2017 who had treatment-naive BRVO with disease onset <3 months before presentation, macular involvement, spectral-domain OCT and color fundus photographs at presentation, and >12 months offollow-up.

METHODS

Retrospective study using a database of patients diagnosed with BRVO over an 8-year period. The presence of fovea-involving IRH was determined from baseline fundus photographs by human graders and confirmed with multimodal imaging. Presenting features, treatment patterns, and clinical outcomes were compared.

MAIN OUTCOME MEASURES

Visual acuity (VA), cystoid macular edema (CME), central subfield thickness (CST), and number of anti-vascular endothelial growth factor (VEGF) injections.

RESULTS

Of 172 patients with BRVO, 33 (19.2%) presented with fovea-involving IRH. At presentation, group A had worse VA (0.54±0.06 logMAR [Snellen equivalent, 20/69] vs. 0.34±0.03 logMAR [Snellen equivalent, 20/44]; P = 0.001), greater CST (523.8±32 μm vs. 345.9±11.8 μm; P < 0.001), were more likely to have CME (93.9% vs. 48.2%; P < 0.001), and received more anti-VEGF injections in the first year (4.50±3.43 vs. 1.89±3.26; P < 0.001) than group B. Final VA was worse in group A (0.57±0.12 logMAR [Snellen equivalent, 20/74] vs. 0.35±0.05 logMAR [Snellen equivalent, 20/45]; P = 0.05). More patients in group A had loss of >2 lines of VA (36.4% vs. 18.7%; P = 0.04) or >3 lines (27.3% vs. 10.8%; P = 0.05) at final follow-up. Group A was more likely to have CME (63.6% vs. 27.3%; P < 0.001) at final follow-up with greater treatment burden, yet experienced a greater decrease in CST (-197.8±45.3 μm vs. -51.7±14.7 μm; P = 0.005).

CONCLUSIONS

Acute BRVO presenting with fovea-involving IRH is associated with worse presenting features, greater treatment burden, and worse clinical outcomes despite current therapeutic interventions.

Sectoral changes of the peripapillary choroidal thickness in patients with unilateral branch retinal vein occlusion

AIM

To investigate sectoral changes in the mean peripapillary choroidal thickness (PCT) in patients with unilateral branch retinal vein occlusion (BRVO).

METHODS

This retrospective, interventional study included 41 patients with acute, unilateral BRVO without macular edema. All patients completed at least a 6-month follow-up period. The PCT was measured at eight locations (temporal, superotemporal, superior, superonasal, nasal, inferonasal, inferior, and inferotemporal). In addition to calculating the average of all locations, the peripapillary choroidal area was divided into four sectors: superior (average of superotemporal PCT, superior PCT, and superonasal PCT), temporal, inferior (average of inferotemporal PCT, inferior PCT, and inferonasal PCT), and nasal.

RESULTS

In the BRVO-affected eyes, the mean PCT was 177.7±69.8 µm (range, 70.1-396.0 µm) at baseline and 127.8±54.8 µm (range, 56.4-312.1 µm) at 6mo (P<0.001). In the non-affected contralateral eyes, the mean PCT was 192.5±60.6 µm (range, 61.4-365.0 µm) at baseline and 165.9±61.1 µm (range, 56.8-326.8 µm) at 6mo (P<0.001). In sectoral analysis, the mean PCT in each sector was significantly reduced in over 6mo in the BRVO-affected eyes (all P<0.001). In the non-affected contralateral eyes, the mean PCT was not significantly changed in any sector over the 6-month follow-up period (superior sector, P=0.143; temporal sector, P=0.825; inferior sector, P=0.192; and nasal sector, P=0.599).

CONCLUSION

Sectoral analysis shows that the mean PCTs in all sectors are reduced significantly over 6mo in the BRVO-affected eyes, but not in the non-affected contralateral eyes.

Morphological Implications of Vascular Structures Not Visualized on Optical Coherence Tomography Angiography in Retinal Vein Occlusion

BACKGROUND AND OBJECTIVE

Advanced retinal imaging can improve understanding of retinal vein occlusion (RVO) pathology. The authors aimed to characterize the vascular pathology of RVO on en face optical coherence tomography (OCT) and OCT angiography (OCTA).

PATIENT AND METHODS

This was a cross-sectional study including 17 eyes with RVO. The authors identified discordance between vasculature on en face OCT and flow on OCTA, which was correlated with structural findings at the corresponding location on OCT B-scans.

RESULTS

Six eyes had vessels that were seen on OCT without flow on OCTA. The most clinically relevant finding was preserved inner retinal layers in areas where the en face OCT showed collaterals that appeared nonperfused on OCTA.

CONCLUSIONS

The authors' findings indicate that collaterals can appear on en face OCT without flow on OCTA in RVO and may be associated with relatively preserved inner retinal structures. Clinicians should consider multimodal imaging to evaluate RVO, including both OCT and OCTA. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:392-396.].

Changes in Retinal Microvasculature and Visual Acuity After Antivascular Endothelial Growth Factor Therapy in Retinal Vein Occlusion

Purpose

To investigate the changes in the retinal microvasculature during the course of anti-VEGF therapy in eyes with macular edema due to retinal vein occlusion (RVO) and their association with visual outcomes.

Methods

The vessel density (VD) and foveal avascular zone (FAZ) area in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were quantitatively measured by optical coherence tomography angiography (OCTA) in 48 consecutive eyes with RVO before and 1, 3, 6, 9, and 12 months after anti-VEGF therapy. Anti-VEGF therapy was performed either with ranibizumab or aflibercept following a pro re nata (PRN) regimen. The correlation between post-treatment best-corrected visual acuity (BCVA) and changes in the retinal microvasculature evaluated by OCTA were assessed.

Results

The BCVA improved significantly at 12 months (P < 0.001). Better BCVA at 12 months was significantly associated with a better VD in the SCP and DCP both at baseline (R2 = 0.524, P < 0.001 and R2 = 0.457, P < 0.001, respectively) and at 12 months (R2 = 0.521, P < 0.001 and R2 = 0.662, P < 0.001, respectively). Overall, both VD and FAZ did not change significantly during the 12 months. However, the progression of nonperfusion was observed in the SCP in 6 (13%) eyes and in the DCP in 10 (21%) eyes. The number of macular edema recurrence was significantly associated with a decrease in the VD (P = 0.006 [SCP] and P < 0.001 [DCP]) and less visual gain (P = 0.02) after treatment.

Conclusions

Anti-VEGF therapy maintains retinal perfusion in most patients with RVO. Preserving retinal perfusion is crucial for better visual outcomes.

Early-scatter laser photocoagulation promotes the formation of collateral vessels in branch retinal vein occlusion

PURPOSE

To investigate the effect of early-scatter laser photocoagulation on the formation of collateral vessels in branch retinal vein occlusion.

METHODS

The medical records of 40 cases (40 patients) of branch retinal vein occlusion with macular edema were retrospectively reviewed. Of them, 23 patients were treated with intravitreal bevacizumab injection and 17 patients underwent intravitreal bevacizumab injection with additional laser treatment. Early-scatter laser photocoagulation was applied for capillary non-perfusion areas, regardless of retinal neovascularization. Collateral vessel presence, recurrence rate of macular edema, and number of intravitreal bevacizumab injections were compared between the groups.

RESULTS

During the follow-up period, collateral vessel formation was noted in 10/23 eyes (43.5%) in the intravitreal bevacizumab injection group and 15/17 eyes (88.2%) in the laser combined treatment group (p = 0.004). The recurrence rate of macular edema was lower in the laser combined treatment group (29.4%) than in the intravitreal bevacizumab injection group (65.2%); this difference was statistically significant (p = 0.025). The average numbers of intravitreal bevacizumab injections were 3.57 ± 3.23 in the intravitreal bevacizumab group and 2.14 ± 2.26 in the laser combined treatment group (p = 0.044).

CONCLUSION

Early-scatter laser photocoagulation promotes collateral vessel formation; the presence of collateral vessels seemed to affect the course of macular edema in branch retinal vein occlusion. Combined early-scatter laser photocoagulation treatment after intravitreal bevacizumab injection lowered the recurrence rate of macular edema and number of intravitreal bevacizumab injections in the cases of branch retinal vein occlusion.

A meta-analysis of patients with treatment-resistant macular oedema secondary to retinal vein occlusions following switching to aflibercept

To systematically review anatomical and functional outcomes of switching therapy from bevacizumab and/or ranibizumab to aflibercept in patients with persistent macular oedema secondary to retinal vein occlusions (RVO). A systematic search of aflibercept for the treatment of persistent macular oedema secondary to branch and central RVO was performed in EMBASE, PubMed and Cochrane databases prior to June 2017. The main outcome variables described were best-corrected visual acuity (BCVA) and central macular thickness (CMT). All results were analysed and pooled using random-effects models with 95% confidence intervals (CI). Eight studies met the inclusion criteria with a total of 137 eyes, incorporating both branch and central RVO. Meta-analysis demonstrated a nonsignificant change in BCVA at 6 and 12 months following switch to aflibercept (4.40 letters, 95% CI: -3.10 to 11.90, p = 0.25 and 3.10 letters, 95% CI: -1.74 to 7.94, p = 0.21, respectively). Significant improvement in mean CMT was observed after switch to aflibercept at 6 (-256.00 μm, 95% CI: -318.00 to -194.00, p < 0.001) but not 12 months (-118.00 μm, 95% CI: -261.00 to 25.00, p = 0.11). Switching from bevacizumab/ranibizumab to aflibercept may improve persistent macular oedema secondary to RVO. However, there may be a limitation in the potential of visual recovery.

Bevacizumab versus bevacizumab and macular grid photocoagulation for macular edema in eyes with non-ischemic branch retinal vein occlusion: results from a prospective randomized study

BACKGROUND

The objective of the study was the investigation of the effects of intravitreal bevacizumab (BEV) with or without additional macular grid laser photocoagulation (GRID) for macular edema (ME) secondary to branch retinal vein occlusion (BRVO).

METHODS

Prospective, randomized, monocentric study. Thirty-two patients were included. Initially, all eyes in both groups received three monthly injections of BEV, followed by additional injections if re-treatment criteria were met. In the BEV + GRID group, photocoagulation was performed 2 weeks after the first BEV injection and laser re-treatment was allowed. The follow-up was 38 weeks. Main outcome measures were best-corrected visual acuity (BCVA) and central retinal thickness (CRT). Changes of foveal avascular zone (FAZ) and of retinal ischemia, as well as the number of injections were also evaluated.

RESULTS

Sixteen eyes were randomized into each group. At baseline, BCVA was similar in both groups (BEV + GRID: 20/71; BEV: 20/60; P = 0.51). At 38 weeks, BCVA significantly improved in the two groups (BEV + GRID gain of 9 ± 11.2 letters and 16.25 ± 10.08 letters in the BEV) with no difference between them (P < 0.06). With regard to anatomical findings, initial CRT in BEV + GRID was 496.2 μm ± 138.4 μm and 538.9 μm ± 156.9 μm in BEV (P < 0.1697). At 38 weeks, CRT decreased in both groups significantly, 98.2 μm in the BEV + GRID (P = 0.02) and 141.7 μm in the BEV group (P = 0.01), with no significant difference between groups (P < 0.17). The area of FAZ a significantly increased in both groups (41% (P = 0.04) in BEV + GRID; 35% (P = 0.03) in BEV) during the study and the grade of peripheral ischemia remained unchanged. The mean number of injections was 3.8 (range 3-6) with no significant difference between groups.

CONCLUSIONS

Our data demonstrate a beneficial effect of bevacizumab in ME in eyes with BRVO. A loading phase of three injections led to a significant improvement in vision in both groups, which persisted at week 38. Additional grid laser photocoagulation exhibited no beneficial functional or anatomical effect during the study, nor did it reduce the number of injections. The FAZ area increased significantly in both groups, but overall retinal ischemia did not. Further studies investigating more numerous eyes and longer follow-up are needed to confirm these data.

Comprehensive analysis of vitreous chemokines involved in ischemic retinal vein occlusion

PURPOSE

To investigate vitreous levels of chemokines in eyes with ischemic retinal vein occlusion (RVO).

METHODS

The vitreous humor was collected at the start of 23-gauge pars plana vitrectomy from patients with ischemic RVO and patients with idiopathic preretinal membranes (PRMs) and idiopathic macular holes (IMHs). The levels of 40 different chemokines were measured using magnetic color-bead-based multiplex assay. The chi-square test was performed for clinical variables such as sex, and the Mann-Whitney U test was performed to evaluate the differences in the chemokine levels between the RVO group and the control group.

RESULTS

Vitreous humor was collected from 20 controls and 25 subjects with ischemic RVO. C-C motif ligand 17 (CCL17) was unmeasurable in more than 70% of the samples. The levels of 29 of 39 chemokines were statistically significantly elevated in the RVO group compared with the control group, including CCL21, C-X-C motif ligand (CXCL) 13, CCL27, CCL24, CX3CL1, CXCL6, interferon-gamma (IFN-γ), interleukin (IL) 1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-16, CXCL10, CXCL11, CCL8, CCL7, CCL13, CCL22, macrophage migration inhibitory factor (MIF), CXCL9, CCL3, CCL15, CCL20, CCL19, CCL23, CCL25, and tumor necrosis factor-alpha (TNF-α). Among the 29 elevated chemokines, we found that the levels of three chemokines (IL-8, CXCL9, and TNF-α) showed a more than six-fold increase in the RVO eyes versus controls, and CXCL9 expression showed the greatest change of all tested chemokines.

CONCLUSIONS

Dozens of chemokines were found to be elevated in the vitreous of RVO eyes complicated with vitreous hemorrhage, suggesting that inflammation is severe in the ischemic retina. The knowledge of specific upregulation of chemokines in ischemic RVO could allow more targeted future therapies.

Histopathological Changes of the Retina After Nd: YAG Laser Thrombolysis in Branch Retinal Vein Occlusion: An Experimental Study

Introduction: The efficacy of many therapeutics techniques for treatment of branch retinal vein occlusion (BRVO) has been the subject of many investigations. The aim of the present work is to evaluate the transluminal Nd: YAG laser thrombolysis as a new therapeutic approach used for treatment of BRVO in rabbits as an experimental model. Methods: Four rabbits were considered as a control (n=8 eyes); occlusion of the branch retinal veins was performed by using a dye enhancing thrombus formation in right eyes of 10 rabbits (n=10 eyes). Thrombi in the retinal veins were induced by intravenous injection of rose bengal solution as a photosensitizer immediately before the argon laser application with a power of 1200 mW, a spot size of 100 µm, and a duration of 20 ms. One week later, transluminal Nd: YAG laser thrombolysis (30 mJ, 3 pulses/4 ns) was employed to the site of occluded veins, until the thrombi were partially or completely shattered. The rabbits were followed up after 4 days, 1 week and 2 weeks for slit lamp fundus examination and the treated retinas were isolated for histopathological examination. Results: Argon laser photothrombosis induced complete BRVO with some vitreous hemorrhage, destruction, and necrosis in the surrounding retinal layers. Moreover, one week later, Nd: YAG laser thrombolysis showed complete venous flow, minimal vitreous hemorrhage, reperfused retina, complete veins improvement. Follow up after 2 weeks revealed more improvement of all retinal layers. Conclusion: Treatment with transluminal Nd: YAG laser thrombolysis represented a novel therapeutic modality in BRVO.

The anti-inflammatory and anti-oxidative effects of conbercept in treatment of macular edema secondary to retinal vein occlusion

To investigate the effects of conbercept on inflammatory and oxidative response in macular edema secondary to retinal vein occlusion (RVO-ME). Retinal microvasculature were detected by optical coherence tomographic angiography (OCTA). The inflammation related factors including prostaglandin E1 (PGE1), prostaglandin E2 (PGE2), prostaglandin F2a (PGF2a), intercellular cell adhesion molecule-1 (ICAM-1) and macrophage inflammatory protein-1 (MIP-1) were determined in human and mice with RVO-ME. OCTA images showed that capillary non-perfusion, enlargement of the foveal avascular zone, telangiectatic vessels and some forms of intraretinal edema in RVO-ME and all these were alleviated by conbercept treatment. PGE1, PGE2, PGF2a, ICAM-1 and MIP-1 in aqueous fluid extracted from RVO-ME patients was significantly increased compared with non-RVO subjects, intravitreal injection of conbercept partly reduced ICAM-1 and MIP-1 levels but not PGE1, PGE2 and PGF2a. The glutathione level was reduced in aqueous fluid extracted from RVO-ME patients but was restored after conbercept treatment. The inflammation, angiogenesis and ROS generation was increased in RVO-ME mice, conbercept partly inhibited these effects. Mechanistically, conbercept inhibited vascular endothelial growth factor (VEGF), ICAM-1, MIP-1, NOX-1 and NOX-4 protein expressions, but not PGE1, PGE2 and PGF2a expressions. Conbercept alleviates RVO-ME through inhibiting inflammation, angiogenesis and oxidative responses. These findings further reveals the molecular mechanism of conbercept for treatment of RVO-ME.

Correlation between retinal vein occlusion and cancer - a nationwide Danish cohort study

PURPOSE

To explore the association between retinal vein occlusion (RVO) and incident cancer.

METHODS

All Danish citizens with a first-time diagnosis of RVO and no previous diagnosis of cancer in the period from 1 January 2004 to 31 December 2014 were included. Five likewise cancer-free, age- and gender-matched controls were included in a control cohort. All were followed up for 5 years or until either first diagnosis of cancer or death. Proportional hazards models with adjustment for age, gender, year of diagnosis and covariates and death as competing risk were used to estimate the risk of being diagnosed with cancer.

RESULTS

There were 7963 RVO patients without cancer at the time of diagnosis, and all could be matched to likewise cancer-free controls. Half of RVO patients were male, and the median age at RVO diagnosis was 70 years (61-79). The control cohort was similar in terms of gender and age. The risk of cancer within 1 year was 1.8 among RVO patients and 1.5 among controls. The crude risk of cancer was 1.22 (1.11;1.34) and upon full adjustment 1.15 (1.05;1.27). No time dependency was detected, and the types of cancer developed in RVO patients and controls were similar.

CONCLUSION

Retinal vein occlusion (RVO) diagnosis is associated with an increased risk of being diagnosed with cancer. This risk is likely to reflect shared risk factors rather than a causal association.

The Analysis of Correlative Factors of Visual Acuity with Intravitreal Conbercept Injection in Macular Edema Associated with Branch Retinal Vein Occlusion

Purpose

To evaluate the correlative factors of best-corrected visual acuity (BCVA) with intravitreal conbercept injection in macular edema secondary to branch retinal vein occlusion (BRVO).

Methods

This is a self-controlled retrospective study. 35 eyes of 35 patients with macular edema secondary to BRVO were enrolled. After an initial intravitreal injection of conbercept (0.5 mg/0.05 ml) monthly up to 3 months, a pro re nata (PRN) strategy was adopted based on the increase in central foveal thickness (CFT). Data collected at various time points include BCVA, CFT, photoreceptor layer thickness (PLT), and outer nuclear layer thickness (ONLT) on optical coherence tomography. The correlation between CFT, PLT, ONLT, and BCVA before and after injections was analyzed.

Results

Compared with baseline, in months 1, 3, and 6 after injection, the improvement of BCVA was 20.63, 22.94, and 21.06 ETDRS letters, respectively (F=195.843, P < 0.01), and the decrease of CFT was 217.37 μm, 224.57 μm, and 224.06 μm, respectively (F=148.522, P < 0.01). The PLT in months 1, 3, and 6 after therapy has significant improvement of 11.14 μm, 13.03 μm, and 13.49 μm (F=64.116, P < 0.01), while the ONLT has a significant decrease of 225.29 μm, 237.66 μm, and 239.11 μm, respectively (F=145.231, P < 0.01). The changes in the treatment group were significant in different periods. The mean number of injections was 3.26 ± 0.50 from baseline to month 6.

Conclusions

Intravitreal injection of conbercept provides an effective treatment for macular edema due to BRVO. With six-month treatment, there were a positive correlation between BCVA and PLT (r=0.592, P < 0.001), a negative correlation between BCVA and ONLT (r=−0.480, P=0.005), and no correlation between BCVA and CFT (P=0.506).

Real-World Results of Switching Treatment from Ranibizumab to Aflibercept in Macular Oedema Secondary to Branch Retinal Vein Occlusion

Introduction

To investigate treatment outcomes after switching from ranibizumab to aflibercept intravitreal injections in patients with macular oedema (MO) secondary to branch retinal vein occlusion (BRVO).

Methods

Eligible patients with refractory MO secondary to BRVO, post treatment with a minimum of three intravitreal injections of ranibizumab at 4-weekly intervals were recruited. Suboptimal or non-responders were defined as patients who had persistent intraretinal fluid (< 75% decrease from baseline) despite a minimum of three consecutive injections. These patients were switched to aflibercept injections on an as-needed basis. The primary study outcomes assessed trends in best-corrected distance visual acuity (BCVA) and central retinal thickness (CRT). To compare means of BCVA and CRT, a paired t test two-tailed with a level of significance set at 0.05 was used. Pearson correlation coefficient was also applied to demonstrate correlation. Participants were followed up for a period of 24 weeks after switching.

Results

Thirty-eight eyes of 38 patients were included in the study. Patients had an average of 8.37 ranibizumab intravitreal injections over a mean period of 12 months presenting suboptimal or no response. A significant decrease of mean CRT from 388.63 ± 93.4 μm to 290.29 ± 93.5 μm (p < 0.001) and an improvement in mean BCVA from logMAR 0.66 ± 0.38 to logMAR 0.57 ± 0.27 (p = 0.025) was achieved after an average of 2.27 aflibercept injections.

Conclusions

Given the spectrum of therapies available to date for the management of MO secondary to BRVO, aflibercept appears to be an effective treatment option in cases refractory to ranibizumab. This study based on a small cohort of patients indicates that satisfactory results on retinal anatomy and visual outcomes can be accomplished with a smaller number of injections. Larger-scale studies are needed to extrapolate these promising results.

Retinal vein thrombosis and risk of occult cancer: A nationwide cohort study

Background

Retinal vein thrombosis has in case reports been reported a clinical sign of cancer, especially hematological cancer. However, it is unclear whether retinal vein thrombosis is a marker of underlying cancer, as is the case for deep venous thrombosis and pulmonary embolism. We investigated the risk of occult cancer in patients with retinal vein thrombosis.

Methods

A nationwide population‐based cohort study in Denmark on all patients diagnosed with a retinal vein thrombosis during 1994 and 2013. The main outcome measures were any cancer and site‐specific cancers <6 months, 6‐12 months, and 5 years following a retinal vein thrombosis diagnosis, as registered in the Danish Cancer Registry and the National Pathology Registry. We calculated the absolute cancer risk and computed standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) for cancer within <6 months, 6‐12 months, and 5 years following a retinal vein thrombosis diagnosis.

Results

Among 9589 patients with retinal vein thrombosis, we observed 1514 cancer cases. The risk of any cancer was 1.2% <6 months and 28.8% after 5 years. The <6 months SIR was 1.20 (95% CI 0.99‐1.44), 6‐12 months SIR was 1.15 (95% CI 0.94‐1.39), and the 5 years’ SIR was 1.08 (95% CI 1.03‐1.14). Stratification by age, gender, calendar year, and Charlson Comorbidity Index score did not change overall cancer risk estimates.

Conclusion

Retinal vein thrombosis was not an important clinical marker for occult cancer. An extensive diagnostic cancer workup does not appear warranted for retinal vein thrombosis patients.

Comparison of one and three initial monthly intravitreal ranibizumab injection in patients with macular edema secondary to branch retinal vein occlusion

AIM

To compare three initial monthly intravitreal ranibizumab (IVR) injections followed by pro re nata (PRN) dosing with one initial monthly IVR injections followed by PRN dosing for macular edema (ME) secondary to branch retinal vein occlusion (BRVO).

METHODS

Forty-two eyes of 42 patients who had IVR injections for BRVO were retrospectively studied. Eighteen eyes received 1 initial IVR injection (1+PRN group) and 24 eyes received 3 monthly IVR injections (3+PRN). At 1, 3, 6 and 12mo; spectral-domain optical coherence tomography (SD-OCT) was performed. Central macular thickness (CMT), the integrity of the external limiting membrane (ELM), the presence of subretinal fluid, cyst size, the presence of inner segment/outer segment (IS/OS) defect were determined.

RESULTS

At baseline the mean CMT was 521.3±153.2 µm in the 3+PRN group while it was 438.1±162.4 µm in 1+PRN group. At the final visit, mean CMT was 278.3±87.8 µm in the 3+PRN group and 285.2±74.2 µm in the 1+PRN group (P=0.079). The changes in CMT over the entire study period were also comparable in both groups (243±160 µm in the 3+PRN group, and 152.9±175.3 µm in the 1+PRN group; P=0.090). At baseline, best-corrected visual acuity (BCVA) was 0.92±0.60 logarithm of the minimal angle of resolution (logMAR) in the 3+PRN group, while it was 0.72±0.46 logMAR in the 1+PRN group. Final BCVA was 0.42±0.55 logMAR in the 3+PRN group and 0.38±0.50 logMAR in the 1+PRN group (P=0.979). Additionally, the BCVA changes from baseline to final visit were not significantly different (-0.50±0.45 logMAR in the 3+PRN group, and -0.33±0.39 logMAR in the 1+PRN group; P=0.255).

CONCLUSION

No significant differences in the anatomical or functional results are found between 3+PRN and 1+PRN regimens in the patients receiving ranibizumab for ME secondary to BRVO. Intact IS/OS and baseline BCVA are good predictor of the visual gain, while baseline CMT is a good predictor of the anatomical gain.

Spontaneous retinal-choroidal anastomosis in a case of branch retinal vein occlusion

PURPOSE

To report a case of a patient affected by branch retinal vein occlusion (BRVO) showing a possible spontaneous retinal-choroidal anastomosis (RCA) at the level of the fovea.

OBSERVATIONS

A 72 years old male patient with diagnosis of BRVO of left eye (LE) one year before came to our observation for a follow-up visit.The patient underwent a complete ophthalmologic examination, including fluorescein angiography, structural optical coherence tomography (OCT), OCT-Angiography (OCT-A). Interestingly, OCT-A revealed the presence of blood flow suggestive of single collateral vessel descending from the deep capillary plexus up to and possibly below a hyperreflective subfoveal deposit.

CONCLUSIONS AND IMPORTANCE

We hypothesize that it can represent a RCA, starting from retinal capillaries and reaching the choriocapillary and choroidal vessels in order to allow a vascular shunt between the 2 circulations and thus a new passage for the blood flow. A similar condition is represented by laser-induced RCA for the treatment of non-ischemic central retinal vein occlusion in order to establish a new passage for the blood flow.

10-year fundus tessellation progression and retinal vein occlusion

AIM

To access the 10-year fundus tessellation progression in patients with retinal vein occlusion.

METHODS

The Beijing Eye Study 2001/2011 is a population-based longitudinal study. The study participants underwent a detailed physical and ophthalmic examination. Degree of fundus tessellation was graded by using fundus photographs of the macula and optic disc. Progression of fundus tessellation was calculated by fundus tessellation degree of 2011 minus degree of 2001. Fundus photographs were used for assessment of retinal vein occlusion.

RESULTS

The Beijing Eye Study included 4403 subjects in 2001, 3468 subjects was repeated in 2011. Assessment of retinal vein obstruction and fundus tessellation progression were available for 2462 subjects (71.0%), with 66 subjects fulfilled the diagnosis of retinal vein occlusion. Of the 66 participants, 59 participants with unilateral branch retinal vein occlusion, 5 participants with unilateral central retinal vein occlusion, 1 participant with bilateral branch retinal vein occlusion, and 1 participant with branch retinal vein occlusion in one eye and central retinal vein occlusion in the other eye. Mean degree of peripapillary fundus tessellation progression were significantly higher in the whole retinal vein occlusion group (0.33±0.39, P<0.001), central retinal vein occlusion group (0.71±0.8, P=0.025) and branch retinal vein occlusion group (0.29±0.34, P=0.006) than the control group (0.20±0.26). After adjustment for age, prevalence of tilted disc, change of best corrected visual acuity, axial length, progression of peripapillary fundus tessellation was associated with the presence of retinal vein occlusion (P=0.004; regression coefficient B, 0.094; 95%CI, 0.029, 0.158; standardized coefficient B, 0.056). As a corollary, after adjusting for smoking duration, systolic blood pressure, anterior corneal curvature, prevalence of RVO was associated with more peripapillary fundus tessellation progression (P<0.001; regression coefficient B: 1.257; OR: 3.517; 95%CI: 1.777, 6.958).

CONCLUSION

Peripapillary fundus tessellation progresses faster in individuals with retinal vein occlusion. This may reflect the thinning and hypoperfusion of choroid in patients with retinal vein occlusion.