Central Retinal Vein Occlusion Eyes Research Articles

Central and Peripheral Changes in Retinal Vein Occlusion and Fellow Eyes in Ultra-Widefield Optical Coherence Tomography Angiography.

To explore the central and peripheral retinal and choroidal changes in retinal vein occlusion (RVO) and fellow eyes using ultra-widefield swept-source optical coherence tomography angiography (UWF-SS-OCTA). Fifteen ischemic central RVO (CRVO), 15 branch RVO (BRVO), and 15 age-matched healthy controls were prospectively recruited. Retinal and choroidal parameters, including retinal vessel flow density (VFD) and vessel linear density (VLD), choroidal vascularity volume (CVV), choroidal vascularity index (CVI), and VFD in the large and medium choroidal vessels (LMCV-VFD), were measured in the central and peripheral regions of the 24 × 20-mm UWF-SS-OCTA images. Ischemic CRVO and BRVO eyes showed increased foveal avascular zone area, perimeter, and acircularity index (AI) compared to their fellow eyes and healthy control eyes, and RVO fellow eyes also had larger AI values than controls (P < 0.05). For ischemic CRVO and BRVO eyes versus control eyes, VFD, VLD, CVV, CVI, and LMCV-VFD decreased, but retinal thickness and volume in the superficial capillary plexus, deep capillary plexus, and whole retina increased (P < 0.05). Moreover, RVO fellow eyes also showed significantly decreased retinal VFD, LMCV-VFD, and CVI, as well as increased retinal thickness and volume, compared with control eyes (P < 0.05). Alterations were not consistent throughout the retina, as they involved only the peripheral or central regions in some cases. The affected and unaffected fellow eyes of RVO patients both demonstrated central and/or peripheral structural and vascular alterations in the retina and choroid. Because UWF-SS-OCTA enables visualization and evaluation of the vasculature outside the posterior pole, it presents a promising approach to more fully characterize vascular alterations in RVO.

Visual and anatomical outcomes following intravitreal treatment of macular oedema secondary to retinal vein occlusion

Aims/Purpose: We sought to measure the visual and anatomical outcomes of patients treated for macular oedema secondary to retinal vein occlusion (RVO) with anti‐vascular endothelial growth factor (VEGF) medications or intravitreal steroids.Methods: We retrospectively identified eyes with RVO in our Trust treated with anti‐VEGF injections or intravitreal steroids. Patient data such as age, gender and visual acuity (VA) were obtained from electronic patient records. Central retinal thickness (CRT) was measured via optical coherence tomography (OCT). Macular perfusion and ischaemia were assessed by fundus fluorescein angiography (FFA) on initiation of treatment. VA and CRT data were obtained for 24 months from starting treatment with anti‐VEGF injections or intravitreal steroids.Results: 56 eyes (26 with branch RVO (BRVO), 22 with central RVO (CRVO) and 8 with hemi‐RVO (HRVO)) were identified and followed up for 24 months after starting anti‐VEGF treatment or intravitreal steroids. Mean change in VA at 24 months was +7.0 ± 16.3 letters among CRVO eyes and + 3.9 ± 21.3 letters among BRVO eyes, whereas for HRVO mean VA change was +20.3 ± 16.8 letters. Mean CRT decreased by 334.2 ± 163.5 μm in eyes with CRVO, 147.1 ± 193.1 μm in eyes with BRVO and 300.3 ± 118.6 μm in eyes with HRVO. Furthermore, we achieved VA stabilization or improvement in 91% of eyes treated under ‘optimal’ conditions, in line with the meta‐analysis of studies on RVO outcomes by Hunter &amp; Williams (2022).Conclusions: Current Trust protocols for intravitreal steroids and anti‐VEGF injections show good outcomes in RVO patients. Patients on treatment should be followed up regularly to minimize delays, while early treatment agent switches should be pursued if VA is dropping or macular oedema persists.ReferencesHunter A, Williams M. Long‐term outcomes for patients treated for macular oedema secondary to retinal vein occlusion: a systematic review. BMJ Open Ophthalmol. 2022;7(1):e001010. doi:10.1136/bmjophth‐2022‐001010

Foveal Eversion is Associated with High Persistence of Macular Edema and Visual Acuity Deterioration in Retinal Vein Occlusion.

Foveal eversion (FE) is a recently described optical coherence tomography (OCT) finding associated with negative outcome in diabetic macular edema. The main goal of the present study was to investigate the role of the FE metric in the diagnostic workup of retinal vein occlusion (RVO). This study was a retrospective, observational case series. We included 168 eyes (168 patients) affected by central RVO (CRVO) and 116 eyes (116 patients) affected by branch (RVO). We collected clinical and imaging data from CRVO and BRVO eyes affected by macular edema with a minimum follow-up of 12months. On structural OCT, we classified FE as pattern 1a, characterized by thick vertical intraretinal columns, pattern 1b, presenting thin vertical intraretinal lines, and pattern 2, showing no signs of vertical lines in the context of the cystoid macular edema. For statistical purposes, we considered data collected at baseline, after 1 year and at the last follow-up. The mean follow-up was 40 ± 25months for CRVO eyes and 36 ± 24months for BRVO eyes. We found FE in 64 of 168 CRVO eyes (38%) and in 25 of 116 BRVO eyes (22%). Most of the eyes developed FE during the follow-up. For CRVO eyes, we found 6 eyes (9%) with pattern 1a, 17 eyes (26%) with pattern 1b and 41 eyes (65%) with pattern 2. Of those BRVO eyes with FE, we found 8 eyes (32%) with pattern 1a + 1b and 17 eyes (68%) with pattern 2. In both CRVO and BRVO the presence of FE was significantly associated with higher persistence of macular edema and worse outcome, with FE pattern 2 representing the most severe condition. Remarkably, FE patterns 1a and 1b were characterized by BCVA stability over the follow-up, whereas FE pattern 2 showed significant bestcorrected visual acuity (BCVA) worsening at the end of the follow-up. FE can be considered a negative prognostic biomarker in RVO, associated with higher persistence of macular edema and worse visual outcome. Müller cell impairment might represent the pathogenic mechanism leading to the loss of macular structural support and impairment of fluid homeostasis.

Real-world effectiveness of intravitreal dexamethasone implants - Comparison between eyes eligible and ineligible for clinical trials and their associated outcomes

BackgroundConcerns about the generalizability of pivotal randomized controlled trials (pRCTs) findings have been raised. We aimed to compare intravitreal dexamethasone implants’ (IDIs) effectiveness for diabetic macular edema (DME) and central retinal vein occlusion (CRVO), between eyes eligible and ineligible for pRCTs. MethodsThis retrospective cohort study analyzed Taiwan's Chang Gung Research Database, including DME or CRVO eyes initiating IDIs during 2015–2020. We classified all treated eyes as eligible or ineligible for pRCTs following major selection criteria of the MEAD and GENEVA trials, and evaluated three-, six-, and twelve-month changes in central retinal thickness (CRT) and visual acuity (VA) after initiating IDIs. ResultsWe included 177 IDI-treated eyes (DME: 72.3%; CRVO: 27.7%), of which 39.8% and 55.1% were ineligible for DME and CRVO pRCTs, respectively. LogMAR-VA and CRT changes at different times were comparable in DME eyes eligible (LogMAR-VA difference: 0.11 to 0.16; CRT difference: −32.7 to −96.9 μm) and ineligible (LogMAR-VA difference: −0.01 to 0.15; CRT difference: −54.5 to −109.3 μm) for the MEAD trial. By contrast, CRVO eyes ineligible for the GENEVA trial had greater LogMAR-VA changes (0.37 ~ 0.50) than those eligible (0.05 ~ 0.13), with comparable CRT reductions (eligible eyes: −72.3 to −106.4 μm; ineligible eyes: −61.8 to −110.7 μm) (all p-values <0.05 of the mean differences between eligible and ineligible CRVO eyes for all follow-ups). ConclusionsIDIs had similar VA and CRT outcomes among DME eyes, regardless of pRCT-eligibility. However, among CRVO eyes, those ineligible for pRCTs showed greater deterioration in VA than those eligible.

Quadrant Asymmetry in Optical Coherence Tomography Angiography Metrics in Ischemic Versus Non-Ischemic Central Retinal Vein Occlusion Eyes.

To determine whether quadrant asymmetry (QA) of optical coherence tomography angiography (OCTA) metrics differs between non-ischemic versus ischemic central retinal vein occlusion (CRVO). Fifty-eight eyes (21 non-ischemic, 10 ischemic CRVO, and 27 contralateral control eyes) underwent 3 × 3 mm spectral-domain OCTA scans with quantification of the superficial retinal layer vessel length density (VLD) and perfusion density (PD). QA, defined as the maximum-minus-minimum value among four parafoveal Early Treatment Diabetic Retinopathy Study (ETDRS) quadrants, was compared by linear regression including fixed effects for each eye. Mean age was 73.6 ± 11.4 (range 39-88), 73.8 ± 12.4 (range 39-91) and 77.2 ± 9.83, (range 60-88); and QA was 3.46 ± 1.76, 3.14 ± 1.57, and 4.88 ± 2.42 for VLD and 0.072 ± 0.038, 0.062 ± 0.036, and 0.11 ± 0.056 for PD for control, non-ischemic, and ischemic, respectively. QA was significantly higher in ischemic (0.109 ± 0.056) than non-ischemic CRVO eyes (0.062 ± 0.036; P = 0.02) and control eyes for PD (0.072 ± 0.038; P = 0.03). QA was also greater in ischemic (4.875 ± 2.418) than non-ischemic CRVO (3.141 ± 1.572) for VLD (P = 0.04). In terms of identifying which particular quadrant is most affected by ischemia, multivariate regression analysis comparing intra-quadrant effect on the presence of ischemia versus non-ischemia showed no quadrant was significantly affected (P > 0.05 for all quadrants). Ischemic CRVO increases intraeye QA of OCTA metrics when compared to non-ischemic CRVO and control eyes. No specific ETDRS quadrant appears to be more affected. This work uses an intraeye method to delineate between ischemic and non-ischemic CRVO by OCTA imaging, overcoming inter-eye variables encountered in clinical care.

Long-term changes in the choroidal thickness in patients with unilateral central retinal vein occlusion

The purpose of this study was to investigate the long-term changes in the choroidal thickness in central retinal vein occlusion (CRVO) following anti-vascular endothelial growth factor (VEGF) treatment. This retrospective study included 41 eyes from 41 patients with treatment-naïve unilateral CRVO. We compared the best-corrected visual acuity (BCVA), subfoveal choroidal thickness (SFCT), and central macular thickness (CMT) of CRVO eyes with those of fellow eyes at baseline, 12 months, and 24 months. Baseline SFCT was significantly higher in CRVO eyes than in fellow eyes (p < 0.001); however, there was no significant difference in the SFCT between CRVO eyes and fellow eyes at 12 months and 24 months. When compared with baseline SFCT, SFCT significantly decreased at 12 months and 24 months in CRVO eyes (all p < 0.001). In patients with unilateral CRVO, SFCT in the CRVO eye was significantly thicker than in the fellow eye at baseline, and after 12 months and 24 months, there was no difference from the fellow eye.

Vessel Pulse Amplitude Mapping in Eyes With Central and Hemi Retinal Venous Occlusion.

The purpose of this study was to describe vessel pulse amplitude characteristics in eyes with central retinal vein occlusion (CRVO), hemiretinal vein occlusion (HVO), normal eyes (N1 N1), and the unaffected contralateral eyes of CRVO and HVO eyes (N1 CRVO and N1 HVO), as well as the unaffected hemivessels of HVO eyes (N2 HVO). Ophthalmodynamometry estimates of blood column pulse amplitudes with modified photoplethysmography were timed against cardiac cycles. Harmonic analysis was performed on the vessel reflectance within 0.25 to 1mm from the disc center to construct pulse amplitude maps. Linear mixed modeling was used to examine variable effects upon the log harmonic pulse amplitude. One hundred seven eyes were examined. Normal eyes had the highest mean venous pulse amplitude (2.08 ± 0.48 log u). CRVO had the lowest (0.99 ± 0.45 log u, P < 0.0001), followed by HVO (1.23 ± 0.46 log u, P = 0.0002) and N2 HVO (1.30 ± 0.59 log u, P = 0.0005). N1 CRVO (1.76 ± 0.34 log u, P = 0.52) and N1 HVO (1.33 ± 0.37 log u, P = 0.0101) had no significantly different mean amplitudes compared to N1 N1. Arterial amplitudes were lower than venous (P < 0.01) and reduced with venous occlusion (P < 0.01). Pulse amplitude versus amplitude over distance decreased along the N1 N1 vessels, with increasing slopes observed with CRVO (P < 0.01). Pulse amplitude reduction and attenuation characteristics of arteries and veins in venous occlusion can be measured and are consistent with reduced vessel wall compliance and pulse wave transmission. Retinal vascular pulse amplitudes can be measured, revealing occlusion induced changes, suggesting a role in evaluating the severity and progression of venous occlusion.

The Choroidal Vascularity Indices of Treatment-Naïve Patients with Central Retinal Vein Occlusion and Age-/Sex-Matched Controls

Purpose: To compare the subfoveal choroidal vascularity indices (CVIs) of treatment-naïve patients with central retinal vein occlusion (CRVO) with controls.Methods: Twenty-one eyes of 21 treatment-naïve CRVO patients and 42 age- and sex-matched control eyes (of 42 subjects) lacking any retinal disease were included. The subfoveal CVIs were measured using ImageJ software.Results: The mean subfoveal CVI in eyes with treatment-naïve CRVO at the initial visit was significantly higher than that of control eyes (0.6464 ± 0.0326 vs. 0.6209 ± 0.0434 respectively; &lt;i&gt;p&lt;/i&gt; = 0.024). In contrast, no significant difference in the mean subfoveal CVI was found between CRVO eyes 6 months after initial diagnosis and control eyes (0.6311 ± 0.0600 vs. 0.6209 ± 0.0434 respectively; &lt;i&gt;p&lt;/i&gt; = 0.238). Of the 21 eyes with CRVO, 18 (85.7%) received intravitreal injections (bevacizumab, ranibizumab, aflibercept, or triamcinolone) and four (19.0%) underwent panretinal photocoagulation.Conclusions: The subfoveal CVI of eyes with treatment-naïve CRVO at the initial visit was significantly higher than that of control eyes, but decreased by 6 months. Further studies are needed to determine whether CRVO treatments such as intravitreal injection or panretinal photocoagulation affect choroid hemodynamics.

Central Retinal Vein Occlusion 36-Month Outcomes with Anti-VEGF: The Fight Retinal Blindness! Registry

To analyze the 3-year outcomes in a broad population of patients starting VEGF inhibitors for central retinal vein occlusion (CRVO) in routine clinical practice. Observational database study. Overall, 527 treatment-naïve CRVO eyes that commenced VEGF inhibitors between December 1, 2010 and 2018 were tracked in the Fight Retinal Blindness! registry. Longitudinal models were used to plot changes in visual acuity (VA) and central subfield thickness (CST). Mean change in VA from baseline to 36 months, injections, visits, completion, switching, and suspensions of therapy > 180 days at the final review. Overall (527 eyes) mean VA change (95% confidence interval [CI]) was+ 10 (7, 12) letters, 37% had final VA ≥ 70 and 30% ≤ 35 letters, mean CST changed-306 μm. Completers (257/527, 49%) had mean 36-month changes in VA and CST of+ 12 letters and-324 μm with a median of 18 injections at 26 visits. The adjusted mean VA change was similar to each VEGF inhibitor (mean,+ 11.4 letters) despite a greater reduction in CST with aflibercept (-310 μm) versus ranibizumab (-258 μm) versus bevacizumab (-216 μm; P < 0.001). Eyes with baseline VA that was trial-eligible (19-73 letters; 356/527, 68%) gained 7 letters, very poor (< 19 letters; 129/527, 24%) gained 22 letters, or very good (> 73 letters; 42/527, 8%) lost 7 letters. Switching (160/527, 30%) was most often to aflibercept (79 eyes). By using suspensions and discontinuation reasons, we identified similar proportions had ceased therapy (154/527, 29%) and were still receiving it at 36 months (165/527, 31%). Only 62/527 eyes (12%) had resolution of macular edema without treatment for > 6 months. Patients with CRVO that commenced VEGF inhibitors in routine care for whom follow-up was available had VA improvements of around 12 letters at 3 years, but with > 50% lost to follow-up, the VA outcome for the entire group was likely worse. The choice of VEGF inhibitor influenced CST but not VA outcomes. We estimated that around half of the eyes were still receiving injections after 36 months. Proprietary or commercial disclosure may be found after the references.

Central corneal thickness, axial length, anterior chamber and optic disc structure in patients with central and branch retinal vein occlusion.

To compare the central corneal thickness (CCT), the structural properties of the anterior chamber and optic disc in patients with central retinal vein occlusion (CRVO), branch retinal vein occlusion (BRVO), and controls. In this prospective study, 31 eyes of 31 CRVO patients (group 1) (mean age: 65.7 ± 10.2 male/female:16/15), 42 eyes of 42 BRVO patients (group 2) (mean age: 61.5 ± 9.9, male/female: 21/21), and 41 controls (mean age: 61.2 ± 15.3, male/female:15/26) were enrolled. Intraocular pressure (IOP), corrected IOP (IOPcorr), central corneal thickness (CCT), anterior chamber depth & volume (ACD & ACV), iridocorneal angle (ICA), axial length (AL), retinal nerve fiber layer (RNFL) thickness, ganglion cell layer (GCL) thickness, cup to disc ratio (C/D), cup & rim volume, the scleral canal diameter (SCD), and mean & pattern deviation in visual field of the eyes with CRVO/BRVO, their fellow eyes and control eyes were evaluated. There was no significant difference in IOP among groups (p:0.239), while IOPcorr was significantly higher in eyes with CRVO compared with eyes with BRVO (p:0.003). Central corneal thickness was significantly thinner in CRVO than both BRVO and controls (p:0.005, p:0.002 respectively). The difference in the RNFL thickness was significant among groups (p:0.019), and it was detected significant between CRVO eyes and controls (p:0.05). Anterior chamber volume was lower in eyes with BRVO than in normal eyes (p:0.009). There was no significant difference in AL, ACD, rim volume, cup volume, GCL thickness, C/D ratio, ICA, and PSD among groups. The patients with CRVO tend to have thinner corneas, and the evaluation of IOP and CCT can be overlooked during retinal follow-up. Intraocular pressure values corrected with CCT should always be take into account to prevent possible optic nerve damage.

Comparison of Each Retinal Layer Thicknesses between Eyes with Central Retinal Vein Occlusion and Normal Contralateral Eyes.

PurposeTo evaluate the difference in each retinal layer thickness in central retinal vein occlusion (CRVO) with resolved macular edema after intravitreal antivascular endothelial growth factor injection and normal contralateral eyes..MethodsPatients with ischemic and nonischemic CRVO whose macular edema resolved after intravitreal antivascular endothelial growth factor injections and did not recur for at least 6 months, and a normal contralateral eye were enrolled. Each retinal layer thickness between CRVO and normal contralateral eyes was compared according to Early Treatment Diabetic Retinopathy Study subfields using spectral domain optical coherence tomography.ResultsThe thicknesses of outer nuclear layer, photoreceptor layer, and retinal pigment epithelium in central ring, ganglion cell layer, inner plexiform layer, outer nuclear layer, and photoreceptor layer in the inner ring, and ganglion cell layer in the outer ring of CRVO eyes were significantly thinner than those of normal contralateral eyes (all p < 0.05). Whereas, inner nuclear layer and outer plexiform layer thicknesses in central ring of CRVO eyes were 23.86 ± 8.8 and 25.76 ± 7.6 μm, respectively, which was significantly thicker than those of normal contralateral eyes (19.52 ± 7.7 and 22.76 ± 6.5 μm; p = 0.019 and p = 0.043, respectively). Additionally, the mean best-corrected visual acuity of CRVO eyes were significantly correlated with photoreceptor layer thickness in central ring (p = 0.005).ConclusionsIn CRVO eyes with resolved macular edema, the outer retinal layers were thinner as well as inner retinal layers, whereas inner plexiform layer and outer nuclear layer were thicker than normal fellow eyes. Additionally, photoreceptor layer thickness in foveal area had a significant impact on visual acuity in CRVO.

Using ultra-widefield red channel images to improve the detection of ischemic central retinal vein occlusion.

To examine the usefulness of red channel fundus imaging to detect the ischemic status in eyes with central retinal vein occlusion (CRVO). Ultra-widefield (UWF) fundus images were obtained from 42 eyes with CRVO. Twenty-one eyes were ischemic, and 21 eyes were non-ischemic. Rubeosis was found in 11 ischemic eyes. UWF images were split into red and green channels using ImageJ software. Both the color and red channel images were used to predict the presence or absence of ischemia when examined by masked graders. The sensitivity and specificity of UWF imagings for the detection of ischemia were calculated in Group A (total 42 eyes), Group B (32 eyes excluding non-rubeotic ischemic CRVO) and Group C (31 eyes excluding rubeotic ischemic CRVO), respectively. Moreover, a linear mixed model was conducted to investigate the relationship between the type of images and the accuracy of prediction in each group. No significant difference in the sensitivity of color fundus imaging was seen between Group A and Group B. By contrast, a significant difference in the sensitivity of red channel imaging was seen between Group A and Group B (p = 0.031). The accuracies of the predictions were not associated with the type of image in Group A and Group B, but were significantly associated in Group C (p = 0.026). UWF red channel imaging enabled more accurate detection of the ischemic status, compared with color fundus images, especially in non-rubeotic CRVO eyes.

Central Retinal Vein Occlusion: The Effect of Antiplatelet and Anticoagulant Agents.

This work evaluates the effect of antiplatelet and anticoagulant agents on clinical outcomes, optical coherence tomography (OCT) parameters, and macular ischemia in eyes with central retinal vein occlusion (CRVO). A retrospective longitudinal cohort study was performed to evaluate patients with CRVO. Demographics, OCT parameters before and after treatment, macular ischemia on fluorescein angiography, and clinical outcomes including the number of injections received were analyzed. A total of 365 patients with CRVO were identified. The average follow-up was 36 months. Antiplatelet or anticoagulant agent use was not associated with a significant difference in visual acuity (VA), prevalence of macular edema, or central subfield thickness on OCT at presentation or final visit. The use of 81-mg aspirin alone was associated with an increased prevalence of foveal hemorrhage at presentation. Patients who were taking an antiplatelet agent, an anticoagulation agent, or both and had an ischemic CRVO with logMAR VA of less than 1.0 experienced improved VA at the final study visit. Patients given antiplatelet or anticoagulant agents had a similar incidence of neovascular sequelae compared with patients not administered these agents. In eyes with CRVO, the use of antiplatelet or anticoagulant agents at CRVO onset was not associated with significantly different functional outcomes, except in ischemic CRVO eyes with VA of less than 20/200. The use of 81-mg aspirin was associated with foveal hemorrhage at CRVO presentation. Otherwise, the use of any antiplatelet agent or anticoagulation was not associated with any CRVO structural outcomes.

Real-Life Management of Central and Branch Retinal Vein Occlusion: A Seven-Year Follow-Up Study.

Retinal vein occlusion is the second most common retinal vascular pathology after diabetic retinopathy and a major cause of vision impairment. Nowadays, both central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO) can be well-managed by intravitreal treatments. However, considering the long-life expectance of the patients, few data are present in the literature about the very long-term outcome of CRVO and BRVO. The present study was an interventional, retrospective analysis of the morphological and functional long-term outcome of CRVO and BRVO patients, followed in an Italian referral center. We collected data from 313 eyes (178 CRVO eyes and 135 BRVO eyes). Mean follow-up was 45 ± 25 months (range 12-84 months). Both CRVO and BRVO eyes experience a significant visual acuity improvement secondary to anti-vascular endothelial growth factor/dexamethasone treatments (from 0.57 ± 0.25 to 0.41 ± 0.24 LogMAR in CRVO and from 0.53 ± 0.42 to 0.30 ± 0.41 LogMAR in BRVO, respectively) (p < 0.01). Also, central macular thickness (CMT) resulted significant recovery at the end of the follow-up (from 585.54 ± 131.43 to 447.88 ± 245.07 μm in CRVO and from 585.54 ± 131.43 to 447.88 ± 245.07 μm in BRVO, respectively) (p < 0.01). CRVO eyes received a mean of 10.70 ± 4.76 intravitreal treatments, whereas BRVO underwent 9.80 ± 5.39 injections over the entire 7-year follow-up. Our analyses highlighted different time points indicating the best obtainable improvement. This was the first year for CRVO (12-month follow-up) and the second year for BRVO (24-month follow-up). After these two time points, both visual acuity and CMT resulted stable up to the end of the follow-up. Ischemia was associated with significantly worse outcome.

Leakage index on ultra-widefield fluorescence angiography in different regions of retina and its correlation with cystoid macular edema in central retinal vein occlusion eyes.

To investigate the relationship between leakage index on ultra-widefield fluorescence angiography (UWFFA) in different regions of retina and its correlation with cystoid macular edema (CME) in central retinal vein occlusion (CRVO) eyes. Patients with naïve non-ischemic CRVO that had undergone UWFFA were identified. UWFFA images in the late phase were used to analyze the leakage index, which was performed by a semi-automatic method using ImageJ. The UWFFA images were subdivided into four regions by concentric circles centered on the macula for analysis. Optical coherence tomography (OCT) images were used to identify the presence of CME and obtain central macular thickness (CMT). A total of 57 eyes from 57 CRVO patients were analyzed in this study, including 43 eyes with CME and 14 eyes without CME. The leakage index in panretinal, peri-macular area (PMA), and near-peripheral area (NPA) was significantly different between eyes with CME and eyes without CME. Leakage index of PMA, NPA, mid-peripheral area (MPA), and panretinal area was significantly correlated with CMT, particularly the PMA. The distribution of leakage is different between patients with CME and patients without CME. The contribution of leakage index in different regions to CME was different, most predominant in PMA and NPA, and the closer to the center of the macula, the stronger the correlation between leakage index and CMT. A linear correlation was observed between CMT and the leakage index of panretinal area and all regions except far-peripheral area (FPA).

Characterization of microvascular tortuosity in retinal vein occlusion utilizing optical coherence tomography angiography

We investigated the characteristics of microvessel tortuosity in branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) and their associations with visual outcomes using optical coherence tomography angiography (OCTA). Thirty-four BRVO and 21 CRVO patients and 31 healthy subjects were included. From OCTA, the branch number (BN), mean branch length (BL), mean Euclidean length (EL), vessel density (VD) and vessel tortuosity (VT) were quantified. In BRVO eyes, compared with that in the controls, the affected area of the deep capillary plexus (DCP) showed a decreased BN and VD, an increased BL, and unchanged VT. The nonaffected area of the DCP showed decreases in BN, VD and VT. The affected area of the superficial capillary plexus (SCP) showed higher VT. In CRVO eyes, the DCP showed a lower BN, VD and VT, while the SCP showed a lower BN and greater BL and EL. Improved visual acuity (VA) after 1 year in BRVO eyes was associated with decreases in BN, BL, VD and VT in the affected area in the DCP and lower VT in the nonaffected area of the SCP; in CRVO eyes, improved VA was associated with a higher BL and EL in the DCP. VT, BL, and EL may be new microvascular markers associated with changes in VA in BRVO and CRVO.

Alterations of the foveal central bouquet associated with cystoid macular edema

ObjectiveThe central bouquet (CB) of the fovea comprises a dense array of cone photoreceptors intertwined with Müller cells. The aim of this investigation was to study visual outcomes and structural alterations in the foveal CB associated with cystoid macular edema (CME) of different etiologies. DesignRetrospective case series. Participants and MethodsThis study analyzed eyes with various etiologies of CME, including diabetic macular edema, central retinal vein occlusion (CRVO), pseudophakic or Irvine–Gass (IG) syndrome, uveitis, and retinitis pigmentosa using spectral-domain optical coherence tomography (SD-OCT). SD-OCT was used to classify the CB alterations as either (1) thickened hyper-reflectivity associated with indistinct ellipsoid zone (EZ), or (2) subretinal fluid with intact EZ. Comparisons were made using the Students t test and Fisher's exact test. ResultsThe total cohort consisted of 61 eyes from 61 patients with various etiologies of CME. CB alterations were observed in 91% of uveitis eyes, 82% of CRVO eyes and 50% of IG eyes. Presence of CB alteration correlated with greater central macular thickness (p = 0.0020), horizontal extent of edema (p = 0.0042), and worse baseline visual acuity (p = 0.0195). Type 2 CB alterations were associated with worse logMAR vision compared with type 1 at baseline and final examinations (p = 0.0002, p = 0.0470). ConclusionsCB alterations were noted in the majority of eyes with CME from CRVO, uveitis, and IG. The association observed between CB alterations and central macular thickness suggests that these alterations may develop as a result of mechanical stress of Müller cells on the CB.

Time-Frequency Analysis of Photopic Negative Response in CRVO Patients

ABSTRACT Purpose The PhNR is driven by retinal ganglion cells (RGCs). Therefore, the function of RGCs could be objectively evaluated by analyzing the PhNR. The aim of this article is to determine the effect of central retinal vein occlusion (CRVO) on PhNR and RGCs performances. Methods Seventeen patients with CRVO were included. Full-field photopic ERGs, including PhNR, were recorded and compared with the fellow normal eyes. ERG signals were analyzed based on the standard time-domain analyses of the PhNR as well as a continuous wavelet transform (CWT) to extract time-frequency components that correspond to the PhNR using MATLAB. We obtained the main frequencies and their occurrence time from CWT. Results All a-wave, b-wave, and PhNR amplitudes of CRVO eyes showed a significant reduction compared to those of the fellow eyes (P < .01, P < .001, and P < .001, respectively). The peak times of a-wave, b-wave, and PhNR were increased significantly in the CRVO eyes (P = .04, P = .04, and P = .003, respectively). The dominant f3 frequency, which corresponds to the PhNR in CRVO patients, showed a more significant decrease (P < .001) compared to other dominant frequencies (f0, f1, and f2). The occurrence time of f3 (t3) was significantly higher in the CRVO eyes (P < .001). Time-domain of the PhNR was also affected in CRVO patients (P < .001). Conclusion CWT allows quantifications of ERG responses, especially for PhNR. The PhNR was severely affected in CRVO eyes implicating loss of RGCs. CWT might demonstrate the severity of CRVO more precisely and identify diagnostically significant changes of ERG waveforms that are not resolved when the analysis is only limited to the time-domain measurements.

Macular profile of eyes developing macular holes in cases of central retinal vein occlusion treated with Bevacizumab

Background: Anti-vascular endothelial growth factors are commonly used for treatment for central retinal vein occlusion. There have been numerous reports regarding both the benefits and disadvantages of its use. Recently, a rather surprising complication- development of macular holes have started emerging.&#x0D; Objectives: The purpose of this study was to evaluate if the patient's profile, baseline optical coherence tomography parameters, status of the vitreous and subsequent response pose a risk for macular hole formation in cases of central retinal vein occlusion central retinal vein occlusion following treatment with bevacizumab. &#x0D; Methodology: This prospective exploratory analytical study was conducted at a tertiary eye care center of Nepal and evaluated 97 eyes with central retinal vein occlusion undergoing treatment with bevacizumab.&#x0D; Results: Full Thickness Macular Hole developed in eight (8.24%) of the central retinal vein occlusion eyes treated with bevacizumab. Elderly age and eyes with cystoid edema at baseline were found to have greater risk of developing macular hole following treatment (OR: 8.97 , p&lt;0.05). Twelve eyes (12.3%) of the eyes treated developed vitreoretinal interface anomalies and were the result of dramatic decrease in central macular thickness . All of them had cystoid macular edema at baseline. Five of them (42%) developed full thickness macular hole.&#x0D; Conclusion: Anti-vascular endothelial growth factor agents have been widely accepted as the first line of choice for treatment of macular edema secondary to central retinal vein occlusion. Cystoid macular edema, eyes of the elderly and those showing dramatic decrease in central macular thickness with the development of anomalous vitreoretinal interface are potential risk factors for full thickness macular hole.

A novel method for electroretinogram assessment in patients with central retinal vein occlusion.

Central retinal vein occlusion (CRVO) is the second most common retinal vascular disorder after diabetic retinopathy that affects the eyes. We propose a method for distinction of normal and central CRVO eyes based on electroretinogram (ERG). Seventeen patients with CRVO in one eye were analyzed. Their ERG signals were collected in six different stimuli, including four records in the darkness (dark-adapted 0.01, dark-adapted 3.0, dark-adapted oscillatory potentials, and dark-adapted 10) and two records in brightness (light-adapted 3.0 and light-adapted 30Hz flicker). Nonlinear features such as Hurst exponent (HE) and approximate entropy (ApEn) were extracted from healthy and CRVO eyes. Finally, a parabolic mapping and two criteria (theta angle and the density of points) were proposed to distinguish the groups. For ApEn, the P values of dark-adapted 3.0 oscillatory (P = 0.0433) and flicker (P = 0.0425) confirmed significant differences between the groups. For HE, the P values of dark-adapted 3.0 oscillatory (P = 0.0421) and flicker 30Hz (P = 0.0402) confirmed differences between the healthy and CRVO groups. The P values of theta angle for dark-adapted 3.0 (P = 0.0199), dark-adapted oscillatory (P = 0.0265), dark-adapted 10.0 (P = 0.0166), light-adapted 3.0 (P = 0.0411), and flicker (P = 0.0361) showed significant differences. Using the density criterion, the statistical test demonstrated a significant difference between the groups in dark-adapted 3 (P = 0.0038), dark-adapted oscillatory (P = 0.0102), dark-adapted 10.0 (P = 0.0071), light-adapted 3.0 (P = 0.0319), and flicker 30Hz (P = 0.0076). The proposed features have made it possible to distinguish between healthy and CRVO eyes. This method could be helpful in some cases with no definite diagnosis or to estimate the severity of CRVO.