Case series of retinal vein occlusions showing early recovery using oral l-methylfolate

This case series describes the aggregate rate of recovery in five consecutive subjects (six eyes) with retinal vein occlusion (RVO) who received l-methylfolate and other vitamins via Ocufolin®, a medical food. Subjects were followed for 10-33 months by a single ophthalmologist. Ocufolin® was prescribed at the time of diagnosis and subjects remained on the regimen throughout the time of observation. Examinations were performed in an un-masked fashion at 3-month intervals with recording of best corrected visual acuity (BCVA), average retinal nerve fiber layer (ARNFL) and central macular thickness (CMT), and fundus (examination of the retina, macula, optic nerve, and vessels) photography. Testing was done for vitamin deficiencies, vascular and coagulable risk factors, and methylenetetrahydrofolate reductase (MTHFR) polymorphisms. Vitamin deficiencies and vascular risk factors were found in all subjects, and all four tested subjects carried at least one MTHFR polymorphism. By the end of the study period BCVA in all subjects was 20/25 or better. Cystoid macular edema was identified and measured by optical coherence tomography (OCT). The percent change was calculated and plotted at 3-month intervals using the percent change in thickness from the time of diagnosis and percent change toward normative values for ARNFL and CMT. The total reduction in thickness of ARNFL and CMT from time of diagnosis was 44.19% and 30.27%, respectively. The comparison to normative data shows a reduction of ARNFL from 164.2% to 94% and CMT from 154.4% to 112.7% of normal thickness (100%). Plots showed the aggregate recovery was most rapid over the first 3 months and slowed over the next 3 months with most of the recovery taking place within 6 months of treatment. The rate of improvement in BCVA and resolution of retinal thickening was found to be better than predicted on historical grounds. No subjects progressed from nonischemic to ischemic RVO. Vitamin deficiencies, vascular risk factors, and genetic predisposition to oxidative stress were common in this RVO series. It appears that addressing these factors with Ocufolin® had a salutary effect on recovery.

Review: The Development of Risk Factors and Cytokines in Retinal Vein Occlusion

Retinal vein occlusion (RVO) is the second most prevalent retinal disease. Despite this, the pathogenic mechanisms and risk factors are not entirely clear. In this article, we review recent publications on the classification, pathogenesis, risk factors, ischemic changes, cytokines, and vital complications of RVO. Risk factors and cytokines are important for exploring the mechanisms and new treatment targets. Furthermore, risk factors are interrelated, making RVO mechanisms more complex. Cytokines act as powerful mediators of pathological conditions, such as inflammation, neovascularization, and macular edema. This review aims to summarize the updated knowledge on risk factors, cytokines of RVO and signaling in order to provide valuable insight on managing the disease.

Phenotyping of retinal neovascularization in ischemic retinal vein occlusion using wide field OCT angiography

BACKGROUND/OBJECTIVES

Abnormal retinal neovascularization caused by ischemic retinal vein occlusion (RVO) is a frequent cause of visually significant vitreous hemorrhage. The early detection of new vessels may be challenging and often requires the use of invasive tests such as fundus fluorescein angiography (FA). We demonstrate the use of wide-field optical coherence tomography angiography (WF-OCTA) in the detection and characterization of neovascularization secondary to ischemic RVO.

SUBJECTS/METHODS

We conducted a retrospective observational case series of patients diagnosed with ischemic RVO between August 2018 and March 2019, who underwent WF-SS-OCTA imaging (PLEX Elite 9000, Carl Zeiss Meditec). We performed real-life montage imaging, covering the involved area and compared the findings of WF-SS-OCTA to standard clinical examination and when available, ultrawide-field fluorescein angiography (UWF-FA, Optos 200TX).

RESULTS

In the included 39 eyes with ischemic RVO, neovascularization elsewhere (NVE) was encountered in 16 of 39 eyes (41%) on WF-OCTA and were characterized as sea-fan type vessels and nodular type vessels, based on their appearance and localization. NVE was identified in 4/39 eyes on standard clinical examination, equating to a detection rate of 10.3%. All were of a sea-fan morphology. In one case, NVE found on WF-OCTA was not observed on UWF-FA, which was a nodular type. Neovascularization of the disc (NVD) was detected in one eye.

CONCLUSIONS

WF-OCTA may become a useful noninvasive tool in the detection of neovascularization in patients with ischemic RVO. Furthermore, the characterization of different morphologies of neovascularization detected by WF-OCTA could be of clinical relevance.

Guidelines for the Management of Retinal Vein Occlusion by the European Society of Retina Specialists (EURETINA)

The high prevalence of cardiovascular disease particularly in the elderly population is associated with retinal vascular disease. Retinal vein occlusions represent severe disturbances of the hypoxia-sensitive neurosensory retina. Acute and excessive leakage leads to the diagnostic hallmarks of retinal hemorrhage and edema with substantial retinal thickening. Advanced diagnostic tools such as OCT angiography allow to evaluate retinal ischemia and identify the risk for late complications and will soon reach clinical routine besides fluorescein angiography. Accordingly, the duration of non-perfusion is a crucial prognostic factor requiring timely therapeutic intervention. With immediate inhibition of vascular leakage, anti-VEGF substances excel as treatment of choice. Multiple clinical trials with optimal potential for functional benefit or a lesser regenerative spectrum have evaluated aflibercept, ranibizumab, and bevacizumab. As retinal vein occlusion is a chronic disease, long-term monitoring should be individualized to combine maintenance with practicability. While steroids may be considered in patients with systemic cardiovascular risk, surgery remains advisable only for very few patients. Destructive laser treatment is an option if reliable monitoring is not feasible. Ophthalmologists are also advised to perform a basic systemic workup to recognize systemic concomitants. The current edition of the EURETINA guidelines highlights the state-of-the-art recommendations based on the literature and expert opinions in retinal vein occlusion.

Reversible retinal vessel closure from VEGF-induced leukocyte plugging

Clinical trials in patients with macular edema due to diabetic retinopathy or retinal vein occlusion (RVO) have shown that suppression of VEGF not only improves macular edema, but also reopens closed retinal vessels, prevents progression of vessel closure, and improves retinopathy. In this study, we show the molecular basis for those clinical observations. Increased retinal levels of VEGF in mice cause plugging of retinal vessels with leukocytes, vessel closure, and hypoxia. Suppression of VEGF reduces leukocyte plugging, causing reperfusion of closed vessels. Activation of VEGFR1 contributes to leukocyte recruitment, because it is significantly reduced by an anti-VEGFR1-neutralizing antibody. High VEGF increases transcriptional activity of NF-κB and expression of NF-κB target genes, particularly Vcam1. Injection of an anti-VCAM-1-neutralizing antibody reduces VEGF-induced leukocyte plugging. These data explain the broad range of benefits obtained by VEGF suppression in patients with ischemic retinopathies, provide an important insight into the pathogenesis of RVO and diabetic retinopathy, and suggest that sustained suppression of VEGF early in the course of these diseases may prevent vessel closure, worsening ischemia, and disease progression. This study also identifies VEGFR1 and VCAM-1 as molecular targets whose suppression could supplement VEGF neutralization for treatment of RVO and diabetic retinopathy.

Seeing through thick and through thin: Retinal manifestations of thrombophilic and hyperviscosity syndromes

The presence of retinal vasculopathy in the absence of typical predisposing factors should suggest a possible underlying hematologic abnormality. In such cases, a systemic investigation may reveal a potentially fatal hypercoagulability or hyperviscosity syndrome. Retinal vein occlusion is the most commonly encountered ophthalmic finding in such syndromes; however, abnormalities of the arterial system, the choroid, and the macula are also possible. Visual symptoms may be the only manifestation of the underlying process, making timely diagnosis by the ophthalmologist critical for both treatment and thrombotic prophylaxis. Moreover, as newer ophthalmic diagnostic technologies arise, there is an increasingly important role for eye physicians in the management of such syndromes.

Intravitreal thrombin activity is elevated in retinal vein occlusion

To evaluate whether intravitreal thrombin activity is elevated in eyes with branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) in comparison to healthy controls. Prospective clinical case series of 19 patients with BRVO, 13 patients suffering from CRVO and nine participants serving as controls. Vitreous taps were extracted from the central vitreous body, 200 μl frozen/thawed sample was immediately stabilized with 200 μl 5% human albumin, and 200 μl mixture thereof was stabilized with 200 μl 2.5 mol/l arginine, pH 8.6. Thrombin activity was determined chromogenically. Intravitreal levels of vascular endothelial growth factor (VEGF) as a marker for blood-retina barrier (BRB) breakdown were measured by a commercial chemiluminescent enzyme immuno assay (R&D). Intravitreal thrombin activity and VEGF levels were 1.6 ± 1.2 mIU/ml (mean value ± SD; range: 0.2-4.2 mIU/ml) and 554 ± 568 pg/ml (range: 20-2005 pg/ml) in BRVO-affected eyes, 2.6 ± 1.2 mIU/ml (range: 0.8-5.2 mIU/ml) and 1332 ± 1350 pg/ml (range: 58-3943 pg/ml) in eyes suffering from CRVO as well as 0.8 ± 0.8 mIU/ml (range: 0.2-2.7 mIU/ml) and 115 ± 120 pg/ml (range: 32-431 pg/ml) in controls. There are significant differences of intravitreal thrombin activity and intravitreal VEGF levels between eyes with BRVO, CRVO, and controls (P = 0.007 and P = 0.003, Kruskal-Wallis test). Intravitreal thrombin activity is significantly correlated with intravitreal VEGF levels (r = 0656; P < 0.001, Pearson correlation). Intravitreal thrombin activity might serve as a new marker for BRB breakdown or macular fibrin deposition in ophthalmology. Significant differences of intravitreal thrombin activity between eyes with BRVO, CRVO, and healthy controls might offer new therapeutic strategies for RVO-affected eyes. The effect of oral and intravitrealy injected direct thrombin inhibitors needs to be evaluated in further investigations.

Doppler flow parameters in orbital arteries in gestational diabetes mellitus patients

OBJECTIVE

To evaluate the blood flow in orbital arteries in patients with gestational diabetes mellitus (GDM).

MATERIAL

We have examined 65 GDM patients and 38 healthy pregnant women at 28-32 weeks. Doppler parameters were assessed in ophthalmic, central retinal and short posterior ciliary arteries.

RESULTS

In ophthalmic arteries V2 was significantly higher and RI lower in GDM. In the subgroup treated with insulin V1 and V2 in ciliary artery and V2 in central retinal artery were significantly lower and PI in ciliary artery was higher when compared to subgroup on diet.

CONCLUSION

Doppler examination can be useful in detection of pre-clinical ophthalmological changes in GDM patients.