Showing papers on "Retinal Vein published in 2017"

Systemic Pharmacokinetics And Pharmacodynamics Of Intravitreal Aflibercept, Bevacizumab, And Ranibizumab

Abstract: Purpose:To evaluate the systemic pharmacokinetics (PKs) of aflibercept, bevacizumab, and ranibizumab in patients with neovascular age-related macular degeneration (AMD), diabetic macular edema (DME), or retinal vein occlusion (RVO).Methods:Prospective, open-label, nonrandomized clinical trial of pat

Optical Coherence Tomography Angiography Analysis of the Foveal Avascular Zone and Macular Vessel Density After Anti-VEGF Therapy in Eyes With Diabetic Macular Edema and Retinal Vein Occlusion

Abstract: Purpose To evaluate the changes in foveal avascular zone (FAZ) area and the retinal capillary density after a single intravitreal anti-VEGF injection for macular edema secondary to diabetic retinopathy or retinal vein occlusion. Methods In this prospective noncomparative case series, 18 eyes of 15 patients with diabetic macular edema (13 eyes) or macular edema secondary to central retinal vein occlusion (5 eyes) were included. Optical coherence tomography angiography (OCTA) images were obtained, and retinal capillary vessel density and FAZ area were measured in the foveal and parafoveal regions at the level of the superficial (SCP) and deep retinal capillary plexus (DCP) before and at the first visit after intravitreal injection. Results The mean interval between baseline and follow up OCTA was 32.5 ± 9.4 (range, 21-50) days. Foveal and parafoveal vessel density in the SCP and DCP were not significantly different before and after intravitreal injection (all P > 0.1), nor was FAZ area (P = 0.48 and P = 0.42, respectively). No significant difference was found between eyes with diabetic macular edema and those with retinal vein occlusion with respect to the mean change of vessel density and FAZ area (all P > 0.05). Conclusions In this pilot study, retinal capillary density and FAZ area remained statistically unchanged in the short-term after a single intravitreal injection of an anti-VEGF agent.

Correlation of microvascular structures on optical coherence tomography angiography with visual acuity in retinal vein occlusion.

Abstract: Purpose:To analyze the correlation of superficial and deep capillary plexuses using optical coherence tomography (OCT) angiography with visual acuity in eyes with retinal vein occlusion (RVO).Methods:We retrospectively reviewed the medical records of 33 patients with retinal vein occlusion (RVO; bra

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN RETINAL VEIN OCCLUSION: Correlations Between Macular Vascular Density, Visual Acuity, and Peripheral Nonperfusion Area on Fluorescein Angiography.

Abstract: PURPOSE To study correlations in patients with retinal vein occlusion between the automatically quantified macular vascular densities in the superficial and deep capillary plexus (DCP) obtained using optical coherence tomography angiography (OCTA) and the data from conventional examination, particularly visual acuity and peripheral retinal nonperfusion assessed using fluorescein angiography (FA). METHODS Retrospective, observational study of patients with retinal vein occlusion who underwent a comprehensive ophthalmic examination including FA and OCTA using the AngioVue OCTA system version 2015.100.0.35 (OptovueRTVue XR 100; AVANTI, Inc, Fremont, CA). Vascular densities in the superficial capillary plexus and DCP, as well as the area of the foveal avascular zone, were measured using the AngioAnalytics software. RESULTS Our study of 65 eyes of 61 patients (33 men, mean age: 67 years) showed a significant correlation between peripheral nonperfusion on FA and (1) automatically quantified global vascular density in both plexus (P = 0.021 for the DCP) and (2) foveal avascular zone area (P = 0.037). We also found significant correlations between capillary dropouts in both plexus and peripheral nonperfusion (P < 0.001 for both) and between visual acuity and vascular densities (P = 0.002 for the global density in the DCP). Global density less than 46% in the DCP was associated to the presence of peripheral nonperfusion area on FA (P = 0.003) and to enlargement of the superficial foveal avascular zone (P = 0.002). CONCLUSION Our study demonstrated a significant correlation between automatically quantified macular vascular density on OCTA and peripheral nonperfusion on FA; OCTA could help identify high-risk retinal vein occlusion patients who may benefit from further evaluation using FA.

Considerations in the Understanding of Venous Outflow in the Retinal Capillary Plexus.

Abstract: Considerations in the Understanding of Venous Outflow in the Retinal Capillary Plexus For many decades, fluorescein angiography has been the gold standard imaging modality for the assessment of retinal perfusion and the evaluation of retinal vascular disorders.1 Fluorescein angiography, however, does not provide sufficient detail of the deep retinal capillary plexus.1–3 More advanced retinal imaging technology, including optical coherence tomography angiography, can now provide depthresolved visualization of the complex anatomy of the retinal vasculature4 and identification of three distinct plexuses in the central macula including the intermediate retinal capillary plexus (ICP),5–7 in addition to the superficial capillary plexus (SCP) and deep capillary plexus (DCP). The ability to image all three plexuses may have important clinical implications for retinal ischemic disorders such as paracentral acute middle maculopathy (PAMM) and acute macular neuroretinopathy, which may be due to capillary ischemia at the ICP and/or DCP levels.8,9 Furthermore, imaging the three plexuses may allow for earlier detection of microvascular changes in disorders such as diabetic retinopathy and macular telangiectasia Type 2.4,5,10 The interrelationships of the retinal capillary plexuses are incompletely understood. Based on their observations using a novel projectionresolved optical coherence tomography angiography algorithm, Campbell and associates recently proposed a model of the three trilaminar microvascular plexuses in which the SCP, ICP, and DCP are arranged in a hammock-like configuration, each communicating through vertically oriented major arteries and veins that are shown to connect with all three plexuses.7 Others have proposed different and/or more complex models.11–15 In this editorial, we wish to offer our interpretations of certain structural features of the retinal microvasculature, particularly as pertains to venous drainage at the level of the DCP. Studies in humans and in animal models have suggested that major arterioles and especially major venules may independently connect to the DCP without first communicating with the SCP, and that the DCP may serve a primarily venous role.5,12,16–19 In a 1996 study, Foreman and associates presented stereoscopic confocal scanning laser microscopic images of the retinal capillary system in human eyes prepared from depth-resolved maximum-intensity immunofluorescence projections.18 Careful inspection of the en face stereopair photographs from this article demonstrates a larger superficial arteriole or venule communicating independently with the DCP, without any connection with the SCP. As Shimizu described in his landmark book entitled Structure of Ocular Vessels: “It even happens, rather frequently, that an (outer) retinal capillary directly drains into a major retinal vein at its posterior aspect.”16 Shimizu’s images of the retinal microvascular casts of macaque monkeys demonstrated this pattern. In a study of neural–vascular relationships in the central retina of macaque monkeys, Snodderly and associates noted that “the deep capillary converged onto tributaries which drained directly into large venous trunks.”17 Studies in mice,12 rats,19 and pigs20 have also suggested that the DCP drains independently into venules, with fewer direct connections between the SCP (and likely the ICP) and the major venular system. We would also like to highlight several other critical aspects regarding the morphology of the DCP. It is generally accepted that the SCP (and perhaps ICP) is arranged as a series of “hammocks” situated between a major artery and vein.14 However, reports have consistently demonstrated that the DCP does not have this “hammock” morphology suggested in the model by Campbell and associates,7 but is instead organized as radial capillaries that converge into a central “vortex” venule that then drains directly into a major venule.5,12,14 In addition, capillary anastomoses directly connecting the SCP, ICP, and DCP have been demonstrated,5,7,12,15,21 the presence of which would imply D. Sarraf receives research grants from Allergan, Genentech, Heidelberg, Regeneron, and Optovue and is a consultant for Amgen, Bayer, Genentech, Novartis, and Optovue. K. B. Freund is a consultant for Genentech, Optovue, Optos, Bayer Healthcare, and Heidelberg Engineering. The other authors have no financial/ conflicting interests to disclose.

Retinal Vein Occlusion Review.

Abstract: Retinal vein occlusions are a very common condition with great importance in ophthalmology clinical practice. This article reviews the salient epidemiology, risk factors, clinical features, and treatments related to retinal vein occlusions.

RANIBIZUMAB FOR RETINAL VEIN OCCLUSION: Predictive Factors and Long-Term Outcomes in Real-Life Data.

Abstract: Purpose:The purpose of the study was to evaluate the long-term anatomical and functional outcomes in patients with retinal vein occlusion (RVO), either central retinal vein occlusion or branch retinal vein occlusion, treated with intravitreal ranibizumab and to determine the predictive factors of th

RANIBIZUMAB FOR MACULAR EDEMA AFTER BRANCH RETINAL VEIN OCCLUSION: One Initial Injection Versus Three Monthly Injections.

Abstract: Purpose:To compare the 12-month-efficacy of 1 initial intravitreal ranibizumab injection (IVR) followed by pro re nata (PRN) dosing with that of three initial monthly IVR followed by PRN dosing in patients with macular edema (ME) after branch retinal vein occlusion.Design:Prospective, interventional

Microglia Activation and Recruitment of Circulating Macrophages During Ischemic Experimental Branch Retinal Vein Occlusion

Abstract: Purpose: To characterize retinal microglia activation and macrophage recruitment in experimental branch retinal vein occlusion (BRVO). Methods: Experimental BRVO was induced in Balb/c mice and histologic changes were studied. Tissue hypoxia was visualized using pimonidazole hydrochloride. Monocyte-derived retinal cells were quantified using histology and flow cytometry. To investigate the dynamics of invading blood-borne macrophages, chimera mice were generated using bone marrow grafts from Cx3cr1(gfp/gfp) mice to rescue lethally irradiated wild-type BALB/c mice. Longitudinal in vivo imaging was performed to monitor cell invasion. The levels of proinflammatory cytokines in the retina were quantified by quantitative real-time PCR. Results: Histology showed disruption of tissue architecture and temporary swelling with marked hypoxia coinciding with increased VEGF-A and hypoxia inducible factor-1α (HIF-1α) expression and elevation of proinflammatory cytokines within 3 days after experimental BRVO, followed by thinning of the inner retinal layers at later time points. Proinflammatory cytokine levels were elevated. Activation of resident retinal microglia and recruitment of circulating macrophages in areas of hypoxic retina were evident early after the insult and peaked at day 7, remaining elevated for up to 28 days. Flow cytometry showed upregulation of CD68 and major histocompatibility complex class-II (MHC-II) expression at day 3, culminating at day 7. Conclusions: Experimental BRVO causes hypoxia and breakdown of the inner blood–retina barrier, followed by activation of microglia and invasion of macrophages from the systemic circulation. Consequently, treatments targeting microglia activation or macrophage recruitment might potentially mitigate the sequelae and attenuate degenerative changes induced by retinal vein occlusion.

Retinal oximetry in patients with ischaemic retinal diseases.

Abstract: The retinal oximeter is a new tool for non-invasive measurement of retinal oxygen saturation in humans. Several studies have investigated the associations between retinal oxygen saturation and retinal diseases. In the present systematic review, we examine whether there are associations between retinal oxygen saturation and retinal ischaemic diseases. We used PubMed and Embase to search for retinal oxygen saturation and retinal ischaemic diseases. Three separate searches identified a total of 79 publications. After two levels of manual screening, 10 studies were included: six about diabetic retinopathy (DR) and four about retinal vein occlusion. No studies about retinal artery occlusion were included. In diabetes, all studies found that increases in retinal venous oxygen saturation (rvSatO2 ) were associated with present as well as increasing levels of DR. Four of six studies also found increased retinal arterial oxygen saturation (raSatO2 ) in patients with DR. In patients with central retinal vein occlusion (CRVO), all studies found that rvSatO2 was reduced, but raSatO2 remained unchanged. Branch retinal vein occlusion was not associated with changes in retinal oxygen saturation, but this was based on a single study. In conclusion, DR is associated with increased rvSatO2 and might also be related to increased raSatO2 . Central retinal vein occlusion (CRVO) is correlated with increased rvSatO2 but unrelated to raSatO2 . Prospective studies are needed to expand these findings. These would tell whether retinal oximetry could be a potential tool for screening or a biomarker of treatment outcome in patients with ischaemic retinal diseases.

A pharmacological approach in newly established retinal vein occlusion model.

Abstract: The mechanism underlying the effects of anti-vascular endothelial growth factor (VEGF) antibody in retinal vein occlusion (RVO) treatment is poorly understood, partly due to the lack of RVO animal models that mimic clinical pathology. The aims of this study were to establish a suitable RVO model, clarify the pathogenic mechanisms, and evaluate the effects of anti-VEGF antibody in the model. Mouse retinal veins were occluded by laser photocoagulation after rose bengal injection. Reduction of the b/a wave amplitude ratio, retinal nonperfusion, cystoid edema, and hard exudates were observed after occlusion, and expression of RVO-related genes was altered. Administration of anti-VEGF antibody immediately, or 7 days, after occlusion resulted in reduction and increase of the nonperfused area, respectively. We conclude that the present model will be useful for clarification of the pathogenic mechanisms, and that the timing of anti-VEGF antibody administration is important for the successful amelioration of retinal nonperfusion.

Dexamethasone intravitreal implant in retinal vein occlusion: real-life data from a prospective, multicenter clinical trial

Abstract: Purpose To evaluate the relationship between duration of macular edema associated with retinal vein occlusion (RVO) and the achievement of vision gain in patients receiving dexamethasone intravitreal implant (DEX implant) in real-world clinical practice, and to define patterns of use of DEX implant and its efficacy and safety in the treatment of patients with RVO in clinical practice.

Evaluation of hyperreflective foci as a prognostic factor of visual outcome in retinal vein occlusion.

Abstract: Aim To evaluate the potential role of hyperreflective foci (HF) as a prognostic indicator of visual outcome in patients with macular edema (ME) due to retinal vein occlusion (RVO) Methods We retrospectively reviewed 50 eyes of 50 patients with ME due to ischemic central retinal vein occlusion (CRVO), non-ischemic CRVO and branch retinal vein occlusion (BRVO) who were treated with anti-vascular endothelial growth factor (anti-VEGF) at Beijing Tongren Eye Center from January 2013 to July 2016 All patients underwent best-corrected visual acuity (BCVA), spectral domain optical coherence tomography (SD-OCT) at baseline and follow-up Such factors were evaluated and compared among three groups as baseline and final BCVA, central retinal thickness (CRT), external limiting membrane (ELM) status and the numbers of HF in different position Multiple linear regression analysis was employed to analyze the relationship between baseline HF and final BCVA Changes of HF before and after treatment were evaluated too Results Among three groups, HF could be located in each retinal layers, as well as in vitreous cavity The mean HF in outer retinal layer (ORL) at baseline was 529±848 in ischemic CRVO with intact ELM, 193±276 in non-ischemic CRVO, and 175±205 in BRVO With disrupted ELM, the mean HF in ORL increased There was statistically difference of HF in ORL between intact and disrupted ELM The numbers of HF in ORL were associated with poor visual outcome among three groups However, HF in inner retinal layer (IRL) and vitreous cavity were not associated with poor visual outcome Meanwhile, the baseline HF in ORL and vitreous cavity reduced significantly in non-ischemic CRVO and BRVO after anti-VEGF treatment Conclusion The numbers of HF in ORL are prognostic factors associated with the final BCVA in patients with ME due to RVO after anti-VEGF treatment

Update on the Use of Anti-VEGF Intravitreal Therapies for Retinal Vein Occlusions.

Abstract: The use of anti-vascular endothelial growth factor (VEGF) therapy in ophthalmology has profoundly changed our management and treatment of conditions such as cystoid macular edema, diabetic macular edema, choroidal neovascularization, and other proliferative retinopathies. Although initially used for the treatment of choroidal neovascularization in neovascular age-related macular degeneration, their application has spread rapidly for other indications as their outcomes have often outperformed previously existing treatments. Retinal vein occlusion (RVO) continues to be one of the leading causes of vision loss secondary to macular edema, in addition to macular ischemia and neovascularization in more severe cases. Before the availability of anti-VEGF therapy, the use of macular grid laser and panretinal photocoagulation was the mainstay of treatment of macular edema and neovascularization, respectively, in patients with RVOs. Two landmarks studies established the guidelines of these treatments for nearly a quarter century. Since the availability of anti-VEGF agents, there has been a paradigm shift in the treatment of RVO. Most importantly, there has also been a significant improvement in visual outcomes in these patients. The goal of this article is to provide a review of the pertinent clinical studies that have investigated the use of anti-VEGF in patients with retinal vein occlusions.

Clinical findings of eyes with macular edema associated with branch retinal vein occlusion refractory to ranibizumab.

Abstract: Purpose:To determine the relationship between the clinical findings and the response to ranibizumab therapy in eyes with macular edema associated with branch retinal vein occlusion.Methods:We reviewed the medical records of 68 patients with macular edema associated with a branch retinal vein occlusi

Towards Robot-Assisted Retinal Vein Cannulation: A Motorized Force-Sensing Microneedle Integrated with a Handheld Micromanipulator †.

Abstract: Retinal vein cannulation is a technically demanding surgical procedure where therapeutic agents are injected into the retinal veins to treat occlusions. The clinical feasibility of this approach has been largely limited by the technical challenges associated with performing the procedure. Among the challenges to successful vein cannulation are identifying the moment of venous puncture, achieving cannulation of the micro-vessel, and maintaining cannulation throughout drug delivery. Recent advances in medical robotics and sensing of tool-tissue interaction forces have the potential to address each of these challenges as well as to prevent tissue trauma, minimize complications, diminish surgeon effort, and ultimately promote successful retinal vein cannulation. In this paper, we develop an assistive system combining a handheld micromanipulator, called “Micron”, with a force-sensing microneedle. Using this system, we examine two distinct methods of precisely detecting the instant of venous puncture. This is based on measured tool-tissue interaction forces and also the tracked position of the needle tip. In addition to the existing tremor canceling function of Micron, a new control method is implemented to actively compensate unintended movements of the operator, and to keep the cannulation device securely inside the vein following cannulation. To demonstrate the capabilities and performance of our uniquely upgraded system, we present a multi-user artificial phantom study with subjects from three different surgical skill levels. Results show that our puncture detection algorithm, when combined with the active positive holding feature enables sustained cannulation which is most evident in smaller veins. Notable is that the active holding function significantly attenuates tool motion in the vein, thereby reduces the trauma during cannulation.

Prevalence, pattern and risk factors of retinal vein occlusion in an elderly population in Nepal: the Bhaktapur retina study.

Abstract: This study aims to explore the prevalence, pattern and risk factors of retinal vein occlusion (RVO) in an elderly population of Nepal. One thousand eight hundred sixty subjects of age 60 years and above were enrolled in a population-based, cross-sectional study. Detailed history, visual acuity, anterior segment and posterior segment examinations were done. Blood pressure, non-fasting blood sugar, body mass index and abdominal girth were measured. Retinal vein occlusions were further divided into branch retinal (BRVO), hemi-retinal and central retinal vein occlusion (CRVO). Age ranged from 60 to 95 years with a mean of 69.64 ± 7.31 years. Overall population prevalence for RVO was 2.95% (95% Confidence interval (CI): 2.23–3.83), BRVO 2.74% (95% CI: 2.05–3.58) and CRVO 0.21% (95% CI: 0.06–0.55). BRVO was seen in 51 subjects (92.73%) and CRVO in 4 (7.27%). Among the total RVO, unilateral and bilateral involvement was 85.45% and 14.55%, respectively. Among the subjects with BRVO and CRVO, 37.25% and 50% had low vision, respectively. The risk of RVO increased with ageing and was more among males. There was an increased risk of RVO among those with hypertension, and with diabetes and hypertension. There was also an increased risk of RVO among subjects with hypermetropia, those with pseudophakia and those who were smokers and consumed alcohol. Retinal vein occlusion is a common retinal vascular disorder in the elderly population of Nepal. The main risk factors for RVO were increasing age and hypertension.

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

Abstract: PurposeRetinal 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 endoth...

Dexamethasone intravitreal implant in retinal vein occlusion:real-life data from a prospective, multicenter clinical trial

Abstract: Several relevant data are missing from the study (Table 1). The study has a selection bias, because 40.8% of the patients included have experienced prior treatments. Likewise, patients with an ophthalmic history of other disease that could affect vision, such as age-related macular degeneration and diabetic retinopathy, were not excluded. On the other hand, re-treatment with dexamethasone implant (DEX implant, Ozurdex; Allergan, Inc., Irvine, CA, USA), the use of other retinal vein occlusion (RVO) therapies in addition to DEX implant, and evaluations of the examinations were at the discretion of the treating physician. Although the best-corrected visual acuity (BCVA) in the study eye ranged from Bhand motion^ and Bfinger counting^ to better than 20/20 Snellen, yet 27 patients with best visual function determined as Bcount fingers^ or Bhand motion^ were excluded from the analysis of BCVA. These patients should have been included in the study after conversion of Snellen BCVA to logarithm of the minimal angle of resolution (LogMAR) and to approximate Early Treatment Diabetic Retinopathy Study letters. The rate of discontinuations or losses of follow-up was too large. At week 24, BCVA and optical coherence tomography were not evaluated to 44.9% and 58.3% of the patients respectively.

Systemic abnormalities associated with retinal vein occlusion in young patients.

Abstract: OBJECTIVES To study the systemic abnormalities associated with retinal vein occlusion in patients aged ≤50 years with a particular emphasis on atherosclerotic diseases and thrombophilic disorders. METHODS Medical charts of patients, aged ≤50 years whose diagnoses were retinal vein occlusions during the period 1995-2015 were retrospectively reviewed. The primary outcome was the number of systemic abnormalities associated with these patients. Secondary outcomes included types of retinal vein occlusion and sites of occlusion. RESULTS Atherosclerotic diseases were the most common systemic abnormalities associated with retinal vein occlusion and accounted for 55.1% of the patients in the study. Hypertension in 27.55%, diabetes mellitus in 16.33%, and 5.1% with dyslipidemia were noted. The number of thrombophilic disorders seemed to be less than expected and were noted in only 5.1%. Other systemic abnormalities included viral hepatitis infection, systemic lupus erythematosus, and acquired immunodeficiency syndrome. Oral contraceptives were used by some patients. CONCLUSION Atherosclerotic diseases remained the most commonly associated systemic diseases in the majority of these patients. Approach to these patients should include a screening for hypertension, diabetes mellitus, and lipid abnormalities. Thrombophilia should also be considered where no obvious atherosclerotic diseases are found or if the patient is <40 years old, a history of thrombosis or a family history of thrombosis is possible.

Comparison of Intravitreal Ranibizumab, Aflibercept, and Dexamethasone Implant after Bevacizumab Failure in Macular Edema Secondary to Retinal Vascular Occlusions

Abstract: Purpose: To compare the visual and anatomic outcomes of macular edema secondary to retinal vein occlusion after switching from bevacizumab to ranibizumab, afliber

Two-year, prospective, multicenter study of the use of dexamethasone intravitreal implant for treatment of macular edema secondary to retinal vein occlusion in the clinical setting in France.

Abstract: 1. There was a selection bias regarding the treatments applied to patients because re-treatments with dexamethasone intravitreal implant (DEX implant, Ozurdex; Allergan, Inc., Irvine, CA, USA) and use of other retinal vein occlusion (RVO) treatments were at the discretion of the physician and patient. 2. There were no data on the criteria used for the classification of RVO into three forms (e.g., ischemic, non-ischemic, and mixed types) nor on the type of optical coherence tomography (OCT) employed (time/spectral domain OCT). 3. There were no comparative data referring to the demographics and baseline ocular characteristics of the three subgroups of patients defined by the treatment received during the 24-month study; e.g., the subgroup 1 consisting of patients treated with a single DEX implant, the subgroup 2 including patients treated with multiple DEX implants, and the subgroup 3 composed of patients treated with a DEX implant plus other RVO treatments. 4. Initially, a comparison had to be carried out between the three subgroups of patients to establish whether or not they are comparable. Accordingly, this comparison should have been conducted only if there were no significant differences between all variables of these three subgroups. 5. In the assessment of the 2-year results of this study, we considered the current assertion [2] according to which evaluation of outcomes should be guided by the anatomic measure data with visual changes as a secondary guide. Despite remarkably visual improvements, the structural outcomes of this study were poor. Thus, the central retinal thickness (CRT) decreased significantly to 380 microns in the entire clinical setting and to 340, 375, and 380microns in the subgroups 1, 2, and 3, respectively, at month 24. Of note, these final CRT values are much more than the cutoff for the upper level of the normal CRT plus two standard deviations, regardless of the OCT type [3, 4] used for evaluations. Moreover, the incidence of adverse events, e.g., cataract progression (39.7 %) and increased intraocular pressure (34.4 %), was fairly high. The persistence of high values of the CRT after treatment highlights unresolved macular edema and indicates that the disease process is still active and progressive, requiring further treatment with anti-angiogenic agents. 6. Nothing was stated referring to the anatomic types of macular edema (ME; subretinal fluid/cystic changes within the neurosensory retina/mixed type) at the end of the study. Likewise, the proportion of eye considered Bdry^ on OCT as per the criterion of CRTs < 250 μm [3] or < 320 μm [4] at month 24 was not indicated. 7. A mean of 2.6 DEX implant injections over 2 years was insufficient to stabilize the ME, the patients being thus impeded from achieving the maximally visual and anatomic benefits. Importantly, the currently valid recommendations, that the duration of ≥ 3-line improvement after a DEX implant is typically 2–3 months [5], and that * Mihai Călugăru mihai.calugaru@mail.dntcj.ro

In Vivo Imaging of Retinal Hypoxia Using HYPOX-4-Dependent Fluorescence in a Mouse Model of Laser-Induced Retinal Vein Occlusion (RVO).

Abstract: Purpose To demonstrate the utility of a novel in vivo molecular imaging probe, HYPOX-4, to detect and image retinal hypoxia in real time, in a mouse model of retinal vein occlusion (RVO). Methods Retinal vein occlusion was achieved in adult mice by photodynamic retinal vein thrombosis (PRVT). One or two major retinal vein(s) was/were occluded in close proximity to the optic nerve head (ONH). In vivo imaging of retinal hypoxia was performed using, HYPOX-4, an imaging probe developed by our laboratory. Pimonidazole-adduct immunostaining was performed and used as a standard ex vivo method for the detection of retinal hypoxia in this mouse RVO model. The retinal vasculature was imaged using fluorescein angiography (FA) and isolectin B4 staining. Retinal thickness was assessed by spectral-domain optical coherence tomography (SD-OCT) analysis. Results By application of the standard ex vivo pimonidazole-adduct immunostaining technique, retinal hypoxia was observed within 2 hours post-PRVT. The observed hypoxic retinal areas depended on whether one or two retinal vein(s) was/were occluded. Similar areas of hypoxia were imaged in vivo using HYPOX-4. Using OCT, retinal edema was observed immediately post-PRVT induction, resolving 8 days later. Nominal preretinal neovascularization was observed at 10 to 14 days post-RVO. Conclusions HYPOX-4 is an efficient probe capable of imaging retinal hypoxia in vivo, in RVO mice. Future studies will focus on its use in correlating retinal hypoxia to the onset and progression of ischemic vasculopathies.

Effects of intravitreal ranibizumab and bevacizumab on the retinal vessel size in diabetic macular edema.

Abstract: PURPOSE The goal of this study was to assess the effects of a single injection of intravitreal ranibizumab (RAN) or bevacizumab (BEV) on the retinal vessel size in eyes with diabetic macular edema. MATERIALS AND METHODS In total, 32 patients were enrolled in the RAN group, and 30 patients were included in BEV group. Each of these groups was also subdivided into two others groups: a study group and a control group. The study groups were composed of the injected eyes, whereas the noninjected fellow eyes served as the control groups. The patients underwent complete ophthalmic examinations, including optical coherence tomography and fundus fluorescein angiography, and the primary outcome measures included the central retinal artery equivalent, central retinal vein equivalent, and artery-to-vein ratio. RESULTS In the RAN study group (n = 32), the preinjection mean central retinal artery equivalent (175.42 μm) decreased to 169.01 μm after 1 week, and to 167.47 μm after 1 month (P < 0.001), whereas the baseline central retinal vein equivalent (235.29 μm) decreased initially to 219.90 μm after 1 week, and to 218.36 μm after 1 month (P < 0.001). In the BEV study group (n = 30), the preinjection central retinal artery equivalent (150.21 μm) decreased to 146.25 μm after 1 week, and to 145.89 μm after 1 month (P < 0.001); whereas the baseline central retinal vein equivalent (211.87 μm) decreased initially to 204.59 μm after 1 week and was 205.24 μm after 1 month (P < 0.001). The preinjection artery-to-vein ratio values changed significantly (P = 0.001) after 1 week and after 1 month in the RAN group, but no significant alteration in the artery-to-vein ratio was observed in the BEV group (P = 0.433). In both the RAN (n = 32) and BEV (n = 30) control groups, none of the 3 parameters changed throughout the study period, when compared with the baseline. CONCLUSION The results of this study showed that both RAN and BEV injections significantly constricted the retinal blood vessel diameters.

Early vitrectomy for dense vitreous hemorrhage in adults with non-traumatic and non-diabetic retinopathy.

Abstract: Objective To evaluate the etiologies for dense vitreous hemorrhage in adults with non-traumatic and reveal management of early vitrectomy for the disease. Methods Study included 105 eyes from 105 patients. Outcome measures were etiologies of vitreous hemorrhage, formation of retinal and/or disk neovascular membrane (NVM), incidence of retinal tear and detachment, visual acuity (VA) and postoperative complications. Results Mean time between presentation and surgery was 7.1 days. The most common etiologies were retinal vein occlusion (RVO) (58.1%), retinal tear (22.9%) and retinal vasculitis (10.4%). Most RVO (77.0%) and retinal vasculitis (72.7%) eyes were associated with retinal and/or disk NVM. Retinal tear and retinal detachment was found in 24 and 48 eyes, respectively. VA improved significantly from 1/70 to 0.6 following vitrectomy. The most common postoperative complication was cataract (28.6%). Conclusion RVO, retinal tear and retinal vasculitis were the most common causes of dense vitreous hemorrhage. Early vitrectomy has a good outcome with acceptable complication rates in this setting.