Global epidemiology of retinal vein occlusion: a systematic review and meta-analysis of prevalence, incidence, and risk factors

Deciphering the interplay of gut microbiota and metabolomics in retinal vein occlusion

This study aims to explore the link between retinal vein occlusion (RVO), a blinding ocular condition, and alterations in gut microbiota composition, to offer insights into the pathogenesis of RVO. Fecal samples from 25 RVO patients and 11 non-RVO individuals were analyzed using 16S rRNA sequencing and liquid chromatography-mass spectrometry (LC-MS). Significant differences in the abundance of gut microbial species were noted between RVO and non-RVO groups. At the phylum level, the RVO group showed an elevation in the ratio of Firmicutes to Bacteroidetes. At the genus level, the RVO group showed higher abundance in Escherichia_Shigella (P < 0.05) and less abundance in Parabacteroides (P < 0.01) than the non-RVO group. Functional predictions indicated reduced folate synthesis, biotin metabolism, and oxidative phosphorylation, with an increase in butyric acid metabolism in the RVO group. LC-MS analysis showed significant differences in purine metabolism, ABC transporters, and naphthalene degradation pathways, especially purine metabolism. Pearson correlation analysis revealed significant associations between bacterial genera and fecal metabolites. Enrichment analysis highlighted connections between specific metabolites and bacterial genera. The findings showed that the dysregulation of gut microbiota was observed in RVO patients, suggesting the gut microbiota as a potential therapeutic target. Modulating the gut microbiota could be a novel strategy for managing RVO and improving patient outcomes. Furthermore, the study findings suggest the involvement of gut microbial dysbiosis in RVO development, underscoring the significance of understanding its pathogenesis for effective treatment development.

IMPORTANCE

Retinal vein occlusion (RVO) is a blinding ocular condition, and understanding its pathogenesis is crucial for developing effective treatments. This study demonstrates significant differences in gut microbiota composition between RVO patients and non-RVO individuals, implicating the involvement of gut microbial dysbiosis in RVO development. Functional predictions and metabolic profiling provide insights into the underlying mechanisms, highlighting potential pathways for therapeutic intervention. These findings suggest that modulating the gut microbiota might be a promising strategy for managing RVO and improving patient outcomes.

Outcomes of anti-VEGF treatment for macular edema secondary to central retinal vein occlusion in patients with poor baseline visual acuity

OBJECTIVE

To report the visual outcomes of intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment for macular edema secondary to central retinal vein occlusion (CRVO) in patients with baseline visual acuity of ≤23 ETDRS letters vision.

DESIGN

Retrospective observational cohort study.

METHODS

This is a single-institution study. A total of 173 eyes from 173 patients who had completed 3 consecutive monthly anti-VEGF injections for macular edema secondary CRVO and best-corrected visual acuity (BCVA) ≤23 ETDRS letters were included. The main outcome measures were visual acuity at month 3 and month 12.

RESULTS

At month 3, BCVA increased to 34.1 ETDRS letters (95% CI, 30.7-37.5), with a gain of 25.0 letters (95% CI, 22.0-28.5; p < 0.001). The mean central subfield thickness decreased by 519 μm (95% CI, 475.5-567.0; p < 0.001). Most patients (67.6%) gained >15 ETDRS letters. A total of 160 patients were followed up for 12 months, and the mean BCVA was 31.2 ETDRS letters (95% CI, 27.5-34.9) at the end of this period. A third of eyes that did not respond (<5-letter gain) after a single injection experienced a 15-letter or more improvement after 3 consecutive injections.

CONCLUSIONS

Anti-VEGF treatment in eyes with CRVO and poor baseline visual acuity results in significant visual improvement, and moderate improvement is still noted despite a poor response after a single injection.

Combination Therapy with Anti-VEGF and Intravitreal Dexamethasone Implant for Macular Edema Secondary to Retinal Vein Occlusion

PURPOSE

To compare the safety and efficacy of intravitreal injection of ranibizumab alone or ranibizumab combined with dexamethasone intravitreal implant in the treatment of macular edema secondary to retinal vein occlusion.

STUDY DESIGN

A single center, case-controlled, prospective cohort study (Clinical Trail Registration Number: ChiCTR2400080048).

METHODS

A total of 44 patients were enrolled and randomized into the ranibizumab group (n = 23) and the combination group (ranibizumab combined with dexamethasone intravitreal implant) (n = 21). All patients received ranibizumab intravitreal injections in the first three months as the initial treatment. For the ranibizumab group, patients might receive repeat injections in case of the recurrence of macular edema; For the combination group, patients received an intravitreal injection of dexamethasone implant after the first injection of ranibizumab at the day 15. The main outcome was best-corrected visual acuity (BCVA) and reduction of central macular thickness. The secondary outcome were the numbers of recurrence, the average injection interval, and the numbers of injection. Adverse events were also recorded.

RESULTS

The BCVAs in both groups were significantly improved compared with the baselines (all p < 0.001), but more increment in BCVA was noticed at the 3-month in the combination group (p = 0.022). Both groups showed a reduction of central macular thickness at all time points (p < 0.05). However, the combination group did not exhibit higher central macular thickness-reducing effects than the ranibizumab group (p > 0.05). Compared with the combination group, the ranibizumab group suffered a higher number of recurrences of macular edema (p < 0.001), a lower interval of injection (p = 0.050), and a higher number of injection (p < 0.011). The incidence of adverse events was not significant between the two groups (p = 0.944).

CONCLUSIONS

Ranibizumab combined with dexamethasone injection sustainably improved the BCVA of retinal vein occlusion patients with a good safety profile.

[Aflibercept in a real-world setting: the AURIGA study : 24-month results of the German cohort of treatment-naïve patients with macular edema following retinal vein occlusion receiving intravitreal aflibercept]

BACKGROUND

AURIGA is the largest prospective real-world study to evaluate intravitreal aflibercept 2 mg (IVT-AFL) treatment of macular edema (ME) secondary to retinal vein occlusion (RVO) and diabetic macular edema. Here we present the 24-month data from the German cohort of treatment-naïve patients with ME due to RVO.

METHODS

Treatment-naïve patients with ME secondary to RVO were treated with IVT-AFL 2 mg in the routine clinical practice. The primary endpoint was mean change in visual acuity (VA, early treatment diabetic retinopathy, ETDRS, letters) at month 12 compared to baseline. Analyses were descriptive.

RESULTS

Analysis included 130 patients with RVO (n = 61, 46.9% with central RVO, n = 69, 53.1% with branch RVO). The mean (± SD) time the RVO patients remained in the study was 18.4 ± 7.4 months. The mean VA gain (95% confidence interval) in the overall cohort was +10.9 (7.5-14.2) letters at month 12 and +9.7 (6.1-13.3) at month 24 (baseline VA 56.5 ± 18.9 letters). At 24 months, 67% of RVO patients gained ≥5 letters and 40% gained ≥15 letters. The mean number of injections was 4.4 ± 1.3 up to month 6, 6.2 ± 2.7 up to month 12 and 8.2 ± 4.5 up to month 24. The mean central retinal thickness (CRT) reduction was -206µm (-252 to -160µm) at 12 months and -219µm (-263 to -175µm) at 24 months (baseline CRT 507 ± 177 µm). The safety profile was consistent with that of previous studies.

DISCUSSION

In the German AURIGA cohort of treatment-naïve patients with ME secondary to RVO, IVT-AFL 2 mg treatment in clinical practice resulted in rapid and clinically relevant VA gains and a reduction in CRT. These results were largely maintained over 24 months despite the low injection frequency from month 6.

Longitudinal changes in each retinal layer thickness in patients with non-ischemic central retinal vein occlusion

BACKGROUND

To identify longitudinal changes in each retinal layer thickness in central retinal vein occlusion (CRVO) patients with resolved macular edema (ME).

METHODS

In this retrospective observational study, CRVO patients without a recurrence of ME for more than 3 years and normal controls were enrolled. Each retinal layer thickness of the parafoveal area, including ganglion cell complex (GCC), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), photoreceptor layer (PRL), and retinal pigment epithelium (RPE) was measured. After the resolution of ME, three more examinations with a 1-year interval were analyzed.

RESULTS

A total of 98 eyes were enrolled, 50 eyes for the control group and 48 eyes for the CRVO group. The baseline GCC thickness was 114.2 ± 15.6 μm and 104.2 ± 25.4 μm in the control and CRVO groups, respectively, which was significantly different (P = 0.022). The thicknesses of other layers including INL, OPL, ONL, PRL, and RPE were not significantly different at baseline. The reduction rate of GCC, INL, OPL, and ONL was - 3.92, - 1.33, - 0.91, and - 2.31 μm/year in the CRVO group, whereas no significant reductions were observed in the control group. Best-corrected visual acuity was significantly associated with changes in the GCC, OPL, and ONL in the CRVO group.

CONCLUSIONS

In patients with CRVO, even in the absence of recurrent ME, retinal damage progresses over time, evidenced by thinning of the inner retina and outer retina including OPL and ONL. These changes may be associated with alterations in visual function.

Time to initiate anti-vascular endothelial growth factor therapy and visual outcome in central retinal vein occlusion

This retrospective study aimed to investigate the progression of central retinal vein occlusion (CVO) prior to treatment initiation and its impact on prognosis. Of the 54 studied eyes with acute CVO, the average logMAR visual acuity (VA) at the initial visit was 0.65 ± 0.49 with an average time to treatment of 14.9 ± 14.5 days. VA at the initial treatment was identified as a stronger predictor of VA at the final visit compared to VA at the first visit or other factors. Patients who received treatment more than 28 days after the initial visit experienced a significant decline in VA compared to those treated within 28 days (0.21 ± 0.35 vs. 0.04 ± 0.13, p = 0.006). Additionally, patients who were treated between 15 and 28 days showed a greater decrease in VA compared to those treated within 14 days (0.12 ± 0.46 vs. 0.018 ± 0.02, p = 0.026). These findings from the current retrospective analysis suggesting that there is a possibility of VA decline at the initial treatment associating with worse prognosis even when treatment is administered within a month should be further investigated in the prospective study. Also, it may be crucial to consider frequent monitoring of acute CVO patients for initiating treatment at the optimal timing.

Fatty Acid-Binding Protein 4-Mediated Regulation Is Pivotally Involved in Retinal Pathophysiology: A Review

Fatty acid-binding proteins (FABPs), a family of lipid chaperone molecules that are involved in intracellular lipid transportation to specific cellular compartments, stimulate lipid-associated responses such as biological signaling, membrane synthesis, transcriptional regulation, and lipid synthesis. Previous studies have shown that FABP4, a member of this family of proteins that are expressed in adipocytes and macrophages, plays pivotal roles in the pathogenesis of various cardiovascular and metabolic diseases, including diabetes mellitus (DM) and hypertension (HT). Since significant increases in the serum levels of FABP4 were detected in those patients, FABP4 has been identified as a crucial biomarker for these systemic diseases. In addition, in the field of ophthalmology, our group found that intraocular levels of FABP4 (ioFABP4) and free fatty acids (ioFFA) were substantially elevated in patients with retinal vascular diseases (RVDs) including proliferative diabetic retinopathy (PDR) and retinal vein occlusion (RVO), for which DM and HT are also recognized as significant risk factors. Recent studies have also revealed that ioFABP4 plays important roles in both retinal physiology and pathogenesis, and the results of these studies have suggested potential molecular targets for retinal diseases that might lead to future new therapeutic strategies.

Retinal Vein Occlusion-Background Knowledge and Foreground Knowledge Prospects-A Review

Thrombosis of retinal veins is one of the most common retinal vascular diseases that may lead to vascular blindness. The latest epidemiological data leave no illusions that the burden on the healthcare system, as impacted by patients with this diagnosis, will increase worldwide. This obliges scientists to search for new therapeutic and diagnostic options. In the 21st century, there has been tremendous progress in retinal imaging techniques, which has facilitated a better understanding of the mechanisms related to the development of retinal vein occlusion (RVO) and its complications, and consequently has enabled the introduction of new treatment methods. Moreover, artificial intelligence (AI) is likely to assist in selecting the best treatment option for patients in the near future. The aim of this comprehensive review is to re-evaluate the old but still relevant data on the RVO and confront them with new studies. The paper will provide a detailed overview of diagnosis, current treatment, prevention, and future therapeutic possibilities regarding RVO, as well as clarifying the mechanism of macular edema in this disease entity.

Risk of stroke development following retinal vein occlusion: A systematic review and meta-analysis

Retinal vein occlusion (RVO) and cerebrovascular disease share common risk factors and may be independently associated; however, the strength and nature of this association remain unclear. We conducted a systematic review and meta-analysis, informed by studies from PubMed, Scopus, EMBASE, Web of Science, and Google Scholar until January 6, 2024, aimed to clarify this relationship. Eligible studies included cohorts observing stroke incidence in RVO patients for over a year. Pooled effect estimates were calculated using random-effects models, with subgroup analyses evaluating associations between RVO types (central and branch) and stroke subtypes (ischemic and hemorrhagic). Ten cohort studies with a total of 428,650 participants (86,299 RVO patients) were included. Compared to controls, RVO patients exhibited a significantly increased risk of stroke (pooled risk ratio [RR]=1.38, 95 % confidence interval (95 %CI)=1.34-1.41). Subgroup analyses indicated elevated risk for both ischemic (RR=1.37, 95 %CI=1.32-1.42) and hemorrhagic (RR=1.55, 95 %CI=1.08-2.22) strokes in RVO patients. Additionally, both central (RR=1.50, 95 %CI=1.27-1.78) and branch (RR=1.41, 95 %CI=1.32-1.50) RVO were associated with stroke risk. Sensitivity analyses confirmed consistent results across various criteria, and funnel plots indicated no publication bias. RVO significantly increases the risk of both ischemic and hemorrhagic stroke, regardless of RVO type, suggesting a strong independent association between these conditions.

Changes in wider field swept-source OCT angiography vascular metrics with anti-vascular endothelial growth factor therapy in central retinal vein occlusion

PURPOSE

To investigate the impact of anti-VEGF therapy on vascular metrics in eyes with macular edema secondary to central retinal vein occlusion (CRVO) using wider field swept-source OCT angiography (WF SS-OCTA).

METHODS

We included 23 eyes with macular edema associated with non-ischemic CRVO from 22 patients treated with anti-VEGF therapy (median number of injections: 5 [2-9]). Changes in vessel density (VD), vessel skeletonized density (VSD), and foveal avascular zone (FAZ) parameters were measured using WF SS-OCTA. Visual acuity (VA) and central subfield thickness (CST) were also measured.

RESULTS

Median CST decreased significantly from 369 µm (305-531) to 267 µm (243-300, p < 0.001). VD and VSD parameters in 12 × 12 mm images showed significant reductions. For instance, VSD in the whole retina decreased from a median of 13.37 (11.22-13.74) to 11.29 (9.36-12.97, p = 0.013). Additionally, a significant increase in FAZ circularity was found, suggesting improved microvascular integrity. Significant inverse correlations were found between the number of anti-VEGF injections and all VSD and VD parameters on the 12 × 12 mm images (p < 0.05). Notably, the reductions in VSD and VD on 12 × 12 mm angiograms in the deep capillary plexus (DCP) after each injection significantly correlated with increased logMAR VA (worse VA).

CONCLUSION

Anti-VEGF therapy in CRVO patients not only mitigates macular edema but also alters the overall microvascular morphology and functionality as revealed by WF SS-OCTA.

Poor response to first intravitreal injection for predicting unfavorable outcomes of retinal vein occlusion related macular edema

PURPOSES

To screen key indicators leading to unfavorable outcomes of retinal vein occlusion related macular edema (RVO-ME) within long-term follow-up duration and to evaluate their predictive values.

METHODS

A study involving patients with RVO-ME was conducted between April 2021 and September 2022. All eligible patients were divided into two groups (favorable and unfavorable group) according to their final best corrected visual acuity (BCVA) and whether neovascular glaucoma (NVG) occurred. The unfavorable group was further divided into subgroups 1 (with BCVA of ≥ 20/400 and < 20/60 and without NVG) and 2 (blindness group, with BCVA of < 20/400 or with NVG). Demographic, past medical history, ocular characteristics and blood parameters were compared between the groups.

RESULTS

A total of 73 eyes from 73 Chinese Han patients (34 males vs. 39 females) with RVO-ME were enrolled. In multivariable regression analysis of continuous variables for unfavorable results, 1-month BCVA after the first intravitreal injection (IVI) was an independent risk factor (odds ratios (ORs) = 2.313, 95% confidence interval (CI) 1.387-3.858, P = 0.001). The area under the curve (AUC) of 1-month BCVA after the first IVI for predicting low vision and blindness was 0.948 (95% CI 0.859-1.000, P < .001) and 0.892 (95% CI 0.744-1.000, P < .001), with a cut-off value of 0.65 logarithm of the minimum angle of resolution (log MAR) (Snellen 20/90) and 1.15 log MAR (Snellen 20/300), respectively.

CONCLUSION

The most valuable indicator for predicting low vision and blindness was poor 1-month BCVA after first IVI compared with favorable group.

Central serous chorioretinopathy: An evidence-based treatment guideline

Central serous chorioretinopathy (CSC) is a relatively common disease that causes vision loss due to macular subretinal fluid leakage and it is often associated with reduced vision-related quality of life. In CSC, the leakage of subretinal fluid through defects in the retinal pigment epithelial layer's outer blood-retina barrier appears to occur secondary to choroidal abnormalities and dysfunction. The treatment of CSC is currently the subject of controversy, although recent data obtained from several large randomized controlled trials provide a wealth of new information that can be used to establish a treatment algorithm. Here, we provide a comprehensive overview of our current understanding regarding the pathogenesis of CSC, current therapeutic strategies, and an evidence-based treatment guideline for CSC. In acute CSC, treatment can often be deferred for up to 3-4 months after diagnosis; however, early treatment with either half-dose or half-fluence photodynamic therapy (PDT) with the photosensitive dye verteporfin may be beneficial in selected cases. In chronic CSC, half-dose or half-fluence PDT, which targets the abnormal choroid, should be considered the preferred treatment. If PDT is unavailable, chronic CSC with focal, non-central leakage on angiography may be treated using conventional laser photocoagulation. CSC with concurrent macular neovascularization should be treated with half-dose/half-fluence PDT and/or intravitreal injections of an anti-vascular endothelial growth factor compound. Given the current shortage of verteporfin and the paucity of evidence supporting the efficacy of other treatment options, future studies-ideally, well-designed randomized controlled trials-are needed in order to evaluate new treatment options for CSC.

Colorimetric Analyses of the Optic Nerve Head and Retina Indicate Increased Blood Flow After Vitrectomy

Purpose

The purpose of this study was to evaluate the impact of vitrectomy and posterior hyaloid (PH) peeling on color alteration of optic nerve head (ONH) and retina as a surrogate biomarker of induced perfusion changes.

Methods

Masked morphometric and colorimetric analyses were conducted on preoperative (<1 month) and postoperative (<18 months) color fundus photographs of 54 patients undergoing vitrectomy, either with (44) or without (10) PH peeling and 31 years of age and gender-matched control eyes. Images were calibrated according to the hue and saturation values of the parapapillary venous blood column. Chromatic spectra of the retinal pigment epithelium and choroid were subtracted to avoid color aberrations. Red, green, and blue (RGB) bit values over the ONH and retina were plotted within the constructed RGB color space to analyze vitrectomy-induced color shift. Vitrectomy-induced parapapillary vein caliber changes were also computed morphometrically.

Results

A significant post-vitrectomy red hue shift was noted on the ONH (37.1 degrees ± 10.9 degrees vs. 4.1 degrees ± 17.7 degrees, P < 0.001), which indicates a 2.8-fold increase in blood perfusion compared to control (2.6 ± 1.9 vs. 0.9 ± 1.8, P < 0.001). A significant post-vitrectomy increase in the retinal vein diameter was also noticed (6.8 ± 6.4% vs. 0.1 ± 0.3%, P < 0.001), which was more pronounced with PH peeling (7.9 ± 6.6% vs. 3.1 ± 4.2%, P = 0.002).

Conclusions

Vitrectomy and PH peeling increase ONH and retinal blood flow. Colorimetric and morphometric analyses offer valuable insights for future artificial intelligence and deep learning applications in this field.

Translational Relevance

The methodology described herein can easily be applied in different clinical settings and may enlighten the beneficial effects of vitrectomy in several retinal vascular diseases.

Disparities in Retinal Vein Occlusion Presentation and Initiation of Anti-VEGF Therapy: An Academy IRIS® Registry Analysis

OBJECTIVE

Investigate disparities in retinal vein occlusion (RVO) presentation and initiation of anti-VEGF treatment.

DESIGN

Retrospective cohort study.

SUBJECTS

Patients in the American Academy of Ophthalmology IRIS® (Intelligent Research in Sight) Registry database (2015-2021) with branch or central RVO and macular edema (ME).

METHODS

The association of demographic characteristics and presenting visual acuity (VA) with anti-VEGF treatment initiation were quantified using multivariable logistic regression.

MAIN OUTCOME MEASURES

Treatment with ≥ 1 anti-VEGF injection within 12 months after RVO diagnosis.

RESULTS

A total of 304 558 eligible patients with RVO and ME were identified. Age at presentation varied by race, ethnicity, sex, and RVO type (all P values < 0.001). Within the first year after RVO presentation, 192 602 (63.2%) patients received ≥ 1 anti-VEGF injection. In a multivariable regression model adjusting for relevant covariates, female (vs. male) patients had lower odds of receiving injections (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.93-0.96; P < 0.0001) as did Black/African American (vs. White) patients (OR, 0.90; 95% CI, 0.88-0.92; P < 0.0001) and Asian (vs. White) patients (OR, 0.95; 95% CI, 0.91-0.99; P = 0.02), whereas older patients (vs. patients aged < 51 years) had higher odds (61-70 years: OR, 1.20; 95% CI, 1.16-1.24; 71-80 years: OR, 1.20; 95% CI, 1.16-1.24; > 80 years: OR, 1.15; 95% CI, 1.11-1.18; all P values < 0.0001). Hispanic (vs. non-Hispanic) patients had a small increased odds of treatment initiation (OR, 1.08; 95% CI, 1.04-1.11; P < 0.0001). Results were similar in the subset of 226 143 patients with VA data. In this subset, patients with presenting VA < 20/40 to 20/200 were most frequently treated in the first year after diagnosis (∼ 70%) and patients with light perception/no light perception (LP-NLP) vision or VA of 20/20 or better were treated least frequently (36.9% and 41.9%, respectively).

CONCLUSIONS

In this large national clinical registry, 37% of RVO patients with ME had no anti-VEGF treatment documented in the first year after diagnosis. Black/African American, Asian, and female patients and patients with VA of LP-NLP were least likely to receive treatment. Awareness of this undertreatment and these disparities highlight the need for initiatives to ensure all RVO patients receive timely anti-VEGF injections for optimized visual outcomes.

FINANCIAL DISCLOSURES

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

Novel Approaches for Early Detection of Retinal Diseases Using Artificial Intelligence

BACKGROUND

An increasing amount of people are globally affected by retinal diseases, such as diabetes, vascular occlusions, maculopathy, alterations of systemic circulation, and metabolic syndrome.

AIM

This review will discuss novel technologies in and potential approaches to the detection and diagnosis of retinal diseases with the support of cutting-edge machines and artificial intelligence (AI).

METHODS

The demand for retinal diagnostic imaging exams has increased, but the number of eye physicians or technicians is too little to meet the request. Thus, algorithms based on AI have been used, representing valid support for early detection and helping doctors to give diagnoses and make differential diagnosis. AI helps patients living far from hub centers to have tests and quick initial diagnosis, allowing them not to waste time in movements and waiting time for medical reply.

RESULTS

Highly automated systems for screening, early diagnosis, grading and tailored therapy will facilitate the care of people, even in remote lands or countries.

CONCLUSION

A potential massive and extensive use of AI might optimize the automated detection of tiny retinal alterations, allowing eye doctors to perform their best clinical assistance and to set the best options for the treatment of retinal diseases.

Comparing ranibizumab, dexamethasone implant, and combined therapy for macular edema secondary to branch retinal vein occlusion: a clinical trial

BACKGROUND

Macular edema (ME) is a common complication following branch retinal vein occlusion (BRVO) and is also the main reason for visual impairment. This study aimed to compare the efficacy and safety of intravitreal ranibizumab (IVR) or dexamethasone implant (IDI) monotherapy, as well as the combination of IVR and IDI injections, in patients with ME secondary to branch retinal vein occlusion (BRVO).

METHODS

This multicenter, prospective, and comparative study included 292 patients with unilateral ME involvement (total of 292 eyes) secondary to BRVO. The patients were randomly assigned to three groups and followed up for 12 months. Patients in group 1 (n = 96) were treated with 3-dose loading IVR injections followed by a pro re nata (PRN) regimen. Patients in group 2 (n = 98) received IVR combined with IDI injection, followed by IVR PRN regimen. Patients in group 3 (n = 98) were treated with IDI injection, followed by repeated IDI injection based on clinical necessity. Best corrected visual acuity (BCVA), central retinal thickness (CRT), complications, and frequency of injections were recorded and compared between the three groups.

RESULTS

At baseline, the three groups did not differ in age, gender, duration of ME, BCVA, IOP, and CRT (P > 0.05). Mean number of total injections per eye within 12 months were 7.1 ± 2.3 (range 4-9) in group 1, 3.7 ± 1.5 (range 2-6) in group 2, and 1.8 ± 0.4 (range 1-3) in group 3. There was a statistical difference in the number of injections between group 1 and group 2 (P = 0.037). Eyes in group 3 received fewer injections than those in group 2, but the difference was not statistically significant (P = 0.052). BCVA improvement and CRT reduction were achieved in all groups and there was no significant difference between the three groups at the end of the 12th month. However, IOP elevation and cataract progression were more frequent in group 3, especially in those patients who received repeated IDI injections.

CONCLUSION

Three therapeutic regimens had comparable efficacy in treating ME secondary to BRVO. Combination therapy had an advantage in maintaining good effect with fewer re-injections and complications.

TRIAL REGISTRATION INFORMATION

The study complied with the principles of the Declaration of Helsinki and was approved by Xi'an Aier Ancient City Eye Hospital, Xi'an Aier Eye Hospital, and Xianyang Aier Eye Hospital ethics committees (2022SF-367).

The measurement and correlation analysis of scleral and choroid thickness in branch retinal vein occlusion

To use Optical Coherence Tomography (OCT) to measure scleral thickness (ST) and subfoveal choroid thickness (SFCT) in patients with Branch Retinal Vein Occlusion (BRVO) and to conduct a correlation analysis. A cross-sectional study was conducted. From May 2022 to December 2022, a total of 34 cases (68 eyes) of untreated unilateral Branch Retinal Vein Occlusion (BRVO) patients were recruited at the Affiliated Eye Hospital of Nanchang University. Among these cases, 31 were temporal branch vein occlusions, 2 were nasal branch occlusions, and 1 was a superior branch occlusion. Additionally, 39 cases (39 eyes) of gender- and age-matched control eyes were included in the study. Anterior Segment Optical Coherence Tomography (AS-OCT) was used to measure ST at 6 mm superior, inferior, nasal, and temporal to the limbus, while Enhanced Depth Imaging Optical Coherence Tomography (EDI-OCT) was used to measure SFCT. The differences in ST and SFCT between the affected eye, contralateral eye, and control eye of BRVO patients were compared and analyzed for correlation. The axial lengths of the BRVO-affected eye, contralateral eye, and control group were (22.92 ± 0.30) mm, (22.89 ± 0.32) mm and (22.90 ± 0.28) mm respectively, with no significant difference in axial length between the affected eye and contralateral eye (P > 0.05). The SFCT and ST measurements in different areas showed significant differences between the BRVO-affected eye, contralateral eye in BRVO patients (P < 0.05). The CRT of BRVO-affected eyes was significantly higher than that of the contralateral eyes and the control eyes (P < 0.001). In comparison between BRVO-affected eyes and control eyes, there were no statistically significant differences in age and axial length between the two groups (P > 0.05). However, significant differences were observed in SFCT and temporal, nasal, superior, and inferior ST between the two groups (P < 0.05). The difference in temporal ST between the contralateral eyes and the control eyes was not statistically significant (t = - 0.35, P = 0.73). However, the contralateral group showed statistically significant increases in SFCT, nasal, superior and inferior ST compared to control eyes (t = - 3.153, 3.27, 4.21, 4.79, P = 0.002, 0.002, < 0.001, < 0.001). However, the difference between the CRT of the contralateral and control eyes was not statistically significant (P = 0.421). When comparing SFCT and ST between BRVO-affected eyes with and without macular edema, no statistically significant differences were found (t = - 1.10, 0.45, - 1.30, - 0.30, 1.00; P = 0.28, 0.66, 0.21, 0.77, 0.33). The thickness of SFCT and temporal ST in major BRVO group is higher than the macular BRVO group and the difference was statistically significant (t = 6.39, 7.17, P < 0.001 for all). Pearson correlation analysis revealed that in BRVO patients, there was a significant positive correlation between SFCT/CRT and temporal ST (r = 0.288, 0.355, P = 0.049, 0.04). However, there was no correlation between SFCT/CRT and nasal ST, superior ST, and inferior ST (P > 0.05). In BRVO patients, both SFCT/CRT and ST increase, and there is a significant correlation between SFCT/CRT and the ST at the site of vascular occlusion.

Subretinal fluid in macular edema secondary to branch retinal vein occlusion

We identified characteristics of patients with subretinal fluid (SRF) in macular edema (ME) secondary to branch retinal vein occlusion (BRVO) and determined their clinical outcomes after anti-vascular endothelial growth factor (VEGF) treatment. Fifty-seven eyes of BRVO patients with ME were divided into two groups according to the presence or absence of SRF at diagnosis. We compared the aqueous profiles, ocular and systemic characteristics at baseline, and the clinical outcomes. The SRF group had significantly greater central subfield thickness (CST) values and poorer best-corrected visual acuity (BCVA) at baseline compared to the non-SRF group. The former group had significantly higher aqueous levels of interleukin-8, VEGF, and placental growth factor. CST reduction and BCVA improvement during treatment were significantly greater in the SRF group than in the non-SRF group. Consequently, CST values were significantly lower in the SRF group than in the non-SRF group at 12 months, when BCVA did not differ significantly between the two groups. The SRF group required more frequent anti-VEGF treatment over 12 months and exhibited a higher rate of macular atrophy. Based on the aqueous profiles and the number of treatments required, the presence of SRF in BRVO patients appears to be associated with higher disease activity.

FABP4 Is an Indispensable Factor for Regulating Cellular Metabolic Functions of the Human Retinal Choroid

The purpose of the current study was to elucidate the physiological roles of intraocularly present fatty acid-binding protein 4 (FABP4). Using four representative intraocular tissue-derived cell types, including human non-pigmented ciliary epithelium (HNPCE) cells, retinoblastoma (RB) cells, adult retinal pigment epithelial19 (ARPE19) cells and human ocular choroidal fibroblast (HOCF) cells, the intraocular origins of FABP4 were determined by qPCR analysis, and the intracellular functions of FABP4 were investigated by seahorse cellular metabolic measurements and RNA sequencing analysis using a specific inhibitor for FABP4, BMS309403. Among these four different cell types, FABP4 was exclusively expressed in HOCF cells. In HOCF cells, both mitochondrial and glycolytic functions were significantly decreased to trace levels by BMS309403 in a dose-dependent manner. In the RNA sequencing analysis, 67 substantially up-regulated and 94 significantly down-regulated differentially expressed genes (DEGs) were identified in HOCF cells treated with BMS309403 and those not treated with BMS309403. The results of Gene Ontology enrichment analysis and ingenuity pathway analysis (IPA) revealed that the DEGs were most likely involved in G-alpha (i) signaling, cAMP-response element-binding protein (CREB) signaling in neurons, the S100 family signaling pathway, visual phototransduction and adrenergic receptor signaling. Furthermore, upstream analysis using IPA suggested that NKX2-1 (thyroid transcription factor1), HOXA10 (homeobox A10), GATA2 (gata2 protein), and CCAAT enhancer-binding protein A (CEBPA) were upstream regulators and that NKX homeobox-1 (NKX2-1), SFRP1 (Secreted frizzled-related protein 1) and TREM2 (triggering receptor expressed on myeloid cells 2) were causal network master regulators. The findings in this study suggest that intraocularly present FABP4 originates from the ocular choroid and may be a critical regulator for the cellular homeostasis of non-adipocyte HOCF cells.

Ischemic and Inflammatory Ocular Adverse Events Following Different Types of Vaccination for COVID-19 and Their Incidence Analysis

PURPOSE

To evaluate the ocular adverse event (OAE) and the incidence rate that can occur after the COVID-19 vaccination.

METHODS

Patients who visited with an ophthalmologic diagnosis within a month of COVID-19 vaccination were retrospectively analyzed. OAEs were categorized as ischemia and inflammation by their presumed pathogenesis and were compared by types of vaccine: messenger RNA (mRNA) and viral vector vaccine. The crude incidence rate was calculated using data from the Korea Disease Control and Prevention Agency.

RESULTS

Twenty-four patients with OAEs after COVID-19 vaccination were reviewed: 10 patients after mRNA and 14 after viral vector vaccine. Retinal vein occlusion (nine patients) and paralytic strabismus (four patients) were the leading diagnoses. Ischemic OAE was likely to occur after viral vector vaccines, while inflammatory OAE was closely related to mRNA vaccine (p = 0.017). The overall incidence rate of OAE was 5.8 cases per million doses: 11.5 per million doses in viral vector vaccine and 3.4 per million doses in mRNA vaccine.

CONCLUSIONS

OAEs can be observed shortly after the COVID-19 vaccination, and their category was different based on the types of vaccine. The information and incidence of OAE based on the type of vaccine can help monitor patients who were administered the COVID-19 vaccine.

Systematic review of clinical practice guidelines for the diagnosis and management of retinal vein occlusion

BACKGROUND/OBJECTIVES

To assess the methodological quality of Clinical Practice Guidelines (CPG) for the diagnosis and management of Retinal Vein Occlusion (RVO).

METHODS

A systematic review of CPGs for the diagnosis and management of RVO was carried out with a search in databases, metasearch engines, CPG development institutions, ophthalmology associations and CPG repositories until April 2022. Search update was performed on April 2023, with no new record available. Five CPGs published in the last 10 years in English/Spanish were selected, and 5 authors evaluated them independently, using the Appraisal of Guidelines for Research and Evaluation (AGREE-II) instrument. An individual assessment of each CPG by domain (AGREE-II), an overall assessment of the guide, and its use with or without modifications were performed. Additionally, a meta-synthesis of the recommendations for the most relevant outcomes was carried out.

RESULTS

The lowest score (mean 18.8%) was for domain 5 'applicability', and the highest score (mean 62%) was for domain 4 'clarity of presentation'. The 2019 American guideline (PPP) presented the best score (40.4%) in domain 3 'rigour of development'. When evaluating the overall quality of the CPGs analysed, all CPGs could be recommended with modifications. In the meta-synthesis, anti-VEGF therapy is the first-choice therapy for macular oedema associated with RVO, but there is no clear recommendation about the type of anti-VEGF therapy to choose. Recommendations for diagnosis and follow-up are similar among the CPGs appraised.

CONCLUSION

Most CPGs for the diagnosis and management of RVO have a low methodological quality assessed according to the AGREE-II. PPP has the higher score in the domain 'rigour of development'. Among the CPGs appraised, there is no clear recommendation on the type of anti-VEGF therapy to choose.

PON1, APOE and SDF-1 Gene Polymorphisms and Risk of Retinal Vein Occlusion: A Case-Control Study

Numerous studies have tried to evaluate the potential role of thrombophilia-related genes in retinal vein occlusion (RVO); however, there is limited research on genes related to different pathophysiological mechanisms involved in RVO. In view of the strong contribution of oxidative stress and inflammation to the pathogenesis of RVO, the purpose of the present study was to investigate the association of inflammation- and oxidative-stress-related polymorphisms from three different genes [apolipoprotein E (APOE), paraoxonase 1 (PON1) and stromal cell-derived factor 1 (SDF-1)] and the risk of RVO in a Greek population. Participants in this case-control study were 50 RVO patients (RVO group) and 50 healthy volunteers (control group). Blood samples were collected on EDTA tubes and genomic DNA was extracted. Genotyping of rs854560 (L55M) and rs662 (Q192R) for the PON1 gene, rs429358 and rs7412 for the APOE gene and rs1801157 [SDF1-3'G(801)A] for SDF-1 gene was performed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Multiple genetic models (codominant, dominant, recessive, overdominant and log-additive) and haplotype analyses were performed using the SNPStats web tool to assess the correlation between the genetic polymorphisms and the risk of RVO. Binary logistic regression analysis was used for the association analysis between APOE gene variants and RVO. Given the multifactorial nature of the disease, our statistical analysis was adjusted for the most important systemic risk factors (age, hypertension and diabetes mellitus). The dominant genetic model for the PON1 Q192R single nucleotide polymorphism (SNP) of the association analysis revealed that there was a statistically significant difference between the RVO group and the control group. Specifically, after adjusting for age and hypertension, the PON1 192 R allele (QR + RR) was found to be associated with a statistically significantly higher risk of RVO compared to the QQ genotype (OR = 2.51; 95% CI = 1.02-6.14, p = 0.04). The statistically significant results were maintained after including diabetes in the multivariate model in addition to age and hypertension (OR = 2.83; 95% CI = 1.01-7.97, p = 0.042). No statistically significant association was revealed between the other studied polymorphisms and the risk of RVO. Haplotype analysis for PON1 SNPs, L55M and Q192R, revealed no statistically significant correlation. In conclusion, PON1 192 R allele carriers (QR + RR) were associated with a statistically significantly increased risk of RVO compared to the QQ homozygotes. These findings suggest that the R allele of the PON1 Q192R is likely to play a role as a risk factor for retinal vein occlusion.

Effectiveness of Mp-3 Microperimetric Biofeedback Fixation Training For Low Vision Rehabilitation in Patients Treated With Corticosteroid Ivt in Retinal Vein Occlusions

Background

The success of fixation training using microperimetric biofeedback (MP-3 MBFT) in the realm of visual rehabilitation for patients with central vision loss caused by macular pathologies is well established. This study aimed to assess the effectiveness and safety of visual rehabilitation with microperimetric biofeedback in consolidating the benefits obtained, with the goal of reducing the need for repeated intravitreal injections (IVT). Specifically, the focus is on the eyes of patients with central vision loss treated with slow-release corticosteroid IVT following retinal venous thrombosis (RVO), aiming to enhance and maintain postoperative efficacy.

Methods

This retrospective review involved the examination of 44 eyes affected by macular edema due to RVO associated with central vision loss. Patients were divided into two groups, with only one undergoing ten sessions of 10-minute visual rehabilitation with a microperimeter (MP-3 MBFT) after IVT over a period of 20 weeks.

Results

All the treated patients demonstrated good tolerance to the procedure, with no reported complications. A comparison of best-corrected visual acuity (BCVA), retinal sensitivity recorded with a microperimeter, and pre-IVT fixation stability revealed statistically significant improvements at the end of the first month after IVT. However, the treatment group continued to exhibit superior and more enduring results at four months post-IV.

Conclusion

The synergistic use of MP-3 MBFT rehabilitation after IVT with slow-release corticosteroids has proven particularly effective in improving BCVA and long-term fixation stability. This led to a significant reduction in the number of required IVTs, with no related adverse events. The authors argue that biofeedback utilization represents a noninvasive therapeutic option devoid of contraindications and easy to implement and that it positively contributes to the overall patient experience regarding quality of life in advanced stages of macular diseases.

Retinal venous occlusion and its association with atherosclerotic vascular disease

Retinal venous occlusion (RVO) is the second most frequent cause of decreased visual acuity due to retinal vascular, after diabetic retinopathy. Its etiology is not completely clear. Current scientific evidence suggests that it is related to the atherosclerotic process given the high number of cardiovascular risk factors and the higher incidence of cardiovascular events in these patients. In fact, RVO implies a 45% higher risk of stroke, 26% of acute myocardial infarction and peripheral vascular disease, 53% of heart failure and 36% of overall mortality, compared to the general population adjusted for age, sex and the different cardiovascular risk factors. However, no increase in cardiovascular mortality has been detected. Therefore, a multidisciplinary clinical approach to this pathology is essential.

RELATIONSHIP BETWEEN RETINAL HEMORRHAGE ON GREEN AND RED CHANNELS OF ULTRA-WIDEFIELD FUNDUS IMAGES AND RETINAL PERFUSION IN ACUTE BRANCH RETINAL VEIN OCCLUSION

PURPOSE

To explore the relationship between retinal hemorrhage in the green and red channels on ultra-widefield fundus images and the nonperfusion area (NPA) on ultra-widefield fundus fluorescein angiography in patients with acute branch retinal vein occlusion (BRVO).

METHODS

This was a retrospective cross-sectional study with 96 patients, including 46 with ischemic BRVO and 50 with nonischemic BRVO. Correlation analysis between green channel hemorrhage (GCH), red channel hemorrhage (RCH), and NPA was performed. Panretina was divided into posterior and peripheral areas.

RESULTS

Ischemic BRVO showed significantly higher GCH% and RCH% than nonischemic BRVO in the peripheral regions (both P < 0.001), whereas no significant differences were observed in the panretinal and posterior areas (all P > 0.05). Significant correlations were found between NPA% in the panretinal and peripheral areas and the corresponding GCH% and RCH% (all P < 0.01). However, no significant correlation was observed between posterior NPA% and posterior GCH% or RCH% (both P > 0.05). In addition, peripheral GCH% and RCH% were related to panretinal NPA% (r = 0.506, P < 0.001; r = 0.558, P < 0.001).

CONCLUSION

Retinal hemorrhage on ultra-widefield fundus image was significantly associated with NPA, providing insights for assessing retinal perfusion status in acute BRVO patients.

Automatic Detection of 30 Fundus Diseases Using Ultra-Widefield Fluorescein Angiography with Deep Experts Aggregation

INTRODUCTION

Inaccurate, untimely diagnoses of fundus diseases leads to vision-threatening complications and even blindness. We built a deep learning platform (DLP) for automatic detection of 30 fundus diseases using ultra-widefield fluorescein angiography (UWFFA) with deep experts aggregation.

METHODS

This retrospective and cross-sectional database study included a total of 61,609 UWFFA images dating from 2016 to 2021, involving more than 3364 subjects in multiple centers across China. All subjects were divided into 30 different groups. The state-of-the-art convolutional neural network architecture, ConvNeXt, was chosen as the backbone to train and test the receiver operating characteristic curve (ROC) of the proposed system on test data and external test date. We compared the classification performance of the proposed system with that of ophthalmologists, including two retinal specialists.

RESULTS

We built a DLP to analyze UWFFA, which can detect up to 30 fundus diseases, with a frequency-weighted average area under the receiver operating characteristic curve (AUC) of 0.940 in the primary test dataset and 0.954 in the external multi-hospital test dataset. The tool shows comparable accuracy with retina specialists in diagnosis and evaluation.

CONCLUSIONS

This is the first study on a large-scale UWFFA dataset for multi-retina disease classification. We believe that our UWFFA DLP advances the diagnosis by artificial intelligence (AI) in various retinal diseases and would contribute to labor-saving and precision medicine especially in remote areas.

Prevalence of retinal pathologies in people over 60 years: the Tehran Geriatrics Eye Study

AIM

To determine the prevalence of some retinal pathologies in people over 60y and their association with demographic and ocular factors.

METHODS

A cross-sectional study was conducted in Tehran using multistage cluster sampling. After selecting subjects aged 60 and over, optometric, and ophthalmic examinations were done. For retinal examination, a 90 D lens was used and indirect ophthalmoscopy was performed after instilling tropicamide drops. Biometry was done using the IOL Master for all participants.

RESULTS

Of 3791 people that were invited through cluster sampling, 3310 participated in the study (response rate=82%). The prevalence of retinal pigmented epithelium (RPE) change, drusen, geographic atrophy (GA), hypertensive retinopathy (HTR), nonproliferative diabetic retinopathy (NPDR), proliferative diabetic retinopathy (PDR), choroidal neovascularization (CNV), central retinal artery occlusion (CRAO), myopic retinopathy (MR), branch retinal vein occlusion (BRVO), and central retinal vein occlusion (CRVO) was 27.42%, 11.08%, 4.52%, 3.03%, 4.05%, 0.54%, 0.82%, 0.39%, 0.20%, 0.49%, and 0.19%, respectively. After removing the effect of age, the odds of NPDR were 1.68 times higher in women compared to men (P=0.014). After removing the effect of sex, the odds of drusen, RPE change, GA, CNV, BRVO, and CRVO increased with age.

CONCLUSION

There is a higher prevalence of RPE change, drusen, GA, CNV and a lower prevalence of MR and CRAO in the elderly population of Tehran aged over 60y compared to global average values. Considering the correlation of most of the diseases with age and their effects on vision, attention should be paid to these diseases and the related screening programs to prevent vision impairment.

Association of PON1, APOE and SDF-1 Gene Polymorphisms with Treatment Response to Intravitreal Anti-VEGF Treatment in Patients with Retinal Vein Occlusion

PURPOSE

The purpose of this study was to determine whether specific genetic polymorphisms affect the response to intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment in patients with macular oedema secondary to retinal vein occlusion (RVO).

METHODS

Participants in this prospective study were 50 patients with macular oedema secondary to RVO, who were treated with intravitreal ranibizumab or aflibercept, and were followed-up for 12 months after initiation of treatment. Five single nucleotide polymorphisms (SNPs) from three different genes (APOE, PON1, SDF-1) were examined as potential predictors for treatment response to intravitreal anti-VEGF agents.

RESULTS

Patients with the LL genotype of the PON1 L55M SNP had significantly higher reduction in central subfield thickness (CST) at month 12 after initiation of intravitreal anti-VEGF treatment (101.63 ± 56.80 μm in LL vs. 72.44 ± 39.41 μm in LM vs. 40.25 ± 19.33 μm in MM, p = .026). Patients with the M allele of the PON1 L55M SNP were significantly associated with lower reduction in CST compared to non-carriers (68.29 ± 38.77 μm in LM + MM vs. 101.63 ± 56.80 μm in LL, p = .032).

CONCLUSION

PON1 L55M SNP may serve as a promising genetic biomarker for predicting response to intravitreal anti-VEGF treatment in patients with macular oedema due to RVO.

Artificial Intelligence (AI) for Early Diagnosis of Retinal Diseases

Artificial intelligence (AI) has emerged as a transformative tool in the field of ophthalmology, revolutionizing disease diagnosis and management. This paper provides a comprehensive overview of AI applications in various retinal diseases, highlighting its potential to enhance screening efficiency, facilitate early diagnosis, and improve patient outcomes. Herein, we elucidate the fundamental concepts of AI, including machine learning (ML) and deep learning (DL), and their application in ophthalmology, underscoring the significance of AI-driven solutions in addressing the complexity and variability of retinal diseases. Furthermore, we delve into the specific applications of AI in retinal diseases such as diabetic retinopathy (DR), age-related macular degeneration (AMD), Macular Neovascularization, retinopathy of prematurity (ROP), retinal vein occlusion (RVO), hypertensive retinopathy (HR), Retinitis Pigmentosa, Stargardt disease, best vitelliform macular dystrophy, and sickle cell retinopathy. We focus on the current landscape of AI technologies, including various AI models, their performance metrics, and clinical implications. Furthermore, we aim to address challenges and pitfalls associated with the integration of AI in clinical practice, including the "black box phenomenon", biases in data representation, and limitations in comprehensive patient assessment. In conclusion, this review emphasizes the collaborative role of AI alongside healthcare professionals, advocating for a synergistic approach to healthcare delivery. It highlights the importance of leveraging AI to augment, rather than replace, human expertise, thereby maximizing its potential to revolutionize healthcare delivery, mitigate healthcare disparities, and improve patient outcomes in the evolving landscape of medicine.

Influence of Smoking and Controlled Medical Conditions on the Risks of Branch Retinal Vein Occlusion in South Korea: A Population-Based Study

PURPOSE

To evaluate the effect of controlled medical conditions and risk of lifetime smoking history on the prevalence of branch retinal vein occlusion (BRVO) based on the Korea National Health and Nutrition Survey (KNHANES) database from 2017-2021.

METHODS

The study population consisted of individuals aged ≥ 40 years who had completed ophthalmological questionnaires, underwent comprehensive ophthalmological examinations, and had at least one good-quality readable fundus photograph. Age, sex, hypertension status, diabetes status, dyslipidemia status, body mass index status, a history of chronic kidney disease (CKD), a lifetime smoking history of ≥ 100 cigarettes, and glaucoma were subjected to univariate and multivariate logistic regression analyses.

RESULTS

The estimated prevalence (± standard error) of RVO was 0.5% (±0.1%). Significant risk factors were one-year increase in age, female sex, hypertension (stage 1, controlled, uncontrolled, and undiagnosed hypertension), underweight, pre-obesity, history of CKD, lifetime smoking history of ≥ 100 cigarettes, and glaucoma. Controlled diabetes decreased the risk of BRVO by 55% (odds ratio [OR] = 0.45, 95% confidence interval [CI] = 0.22-0.89, p = 0.022) and controlled hyper-high-density-lipoprotein (HDL)-cholesterolemia decreased the risk by 69% (OR = 0.31, 95% CI = 0.13-0.76, p = 0.010).

CONCLUSION

This study, for the first time, reported the association between lifetime smoking history of ≥ 100 cigarettes and BRVO in Korea. The risk of BRVO was lower in participants with controlled diabetes and hypo-HDL-cholesterolemia.

Initial response and 12-month outcomes after commencing dexamethasone or vascular endothelial growth factor inhibitors for retinal vein occlusion in the FRB registry

To compare baseline characteristics, initial response and 12-month efficacy and safety outcomes in eyes with branch and central retinal vein occlusion (BRVO and CRVO) treated with dexamethasone implants (DEX) or anti-vascular endothelial growth factor (anti-VEGF) we performed a multi-centre, retrospective and observational study using Fight Retinal Blindness! Registry. Of 725 eligible eyes, 10% received DEX initially with very frequent adjunctive anti-VEGF (BRVO-DEX 49%, CRVO-DEX 60%). The primary outcome of mean adjusted change in VA at 12 months with DEX and anti-VEGF initiated groups were not statistically significantly different (BRVO: DEX + 6.7, anti-VEGF + 10.6 letters; CRVO: DEX + 2.8, anti-VEGF + 6.8 letters). DEX initiated eyes had fewer injections and visits than anti-VEGF initiated eyes. The BRVO-DEX eyes had greater initial mean changes in VA and central subfield thickness (CST) and achieved inactivity sooner than BRVO-anti-VEGF eyes. The mean CST after the first three months was above 350 μm in all but the BRVO-anti-VEGF group, suggesting undertreatment. In routine care DEX is uncommonly used when available as initial treatment of BRVO and CRVO requiring supplemental anti-VEGF within the first year. The 12-month outcomes were similar, but DEX initiated eyes had fewer injections and visits but more episodes of raised IOP Vs those starting anti-VEGF.

Visualizing features with wide-field volumetric OCT angiography

Optical coherence tomography (OCT) and its extension OCT angiography (OCTA) have become essential clinical imaging modalities due to their ability to provide depth-resolved angiographic and tissue structural information non-invasively and at high resolution. Within a field of view, the anatomic detail available is sufficient to identify several structural and vascular pathologies that are clinically relevant for multiple prevalent blinding diseases, including age-related macular degeneration (AMD), diabetic retinopathy (DR), and vein occlusions. The main limitation in contemporary OCT devices is that this field of view is limited due to a fundamental trade-off between system resolution/sensitivity, sampling density, and imaging window dimensions. Here, we describe a swept-source OCT device that can capture up to a 12 × 23-mm field of view in a single shot and show that it can identify conventional pathologic features such as non-perfusion areas outside of conventional fields of view. We also show that our approach maintains sensitivity sufficient to visualize novel features, including choriocapillaris morphology beneath the macula and macrophage-like cells at the inner limiting membrane, both of which may have implications for disease.

Optimizing numerical k-sampling for swept-source optical coherence tomography angiography

High-quality swept-source optical coherence tomography (SS-OCT) requires accurate k-sampling, which is equally vital for optical coherence tomography angiography (OCTA). Most SS-OCT systems are equipped with hardware-driven k-sampling. However, this conventional approach raises concerns over system cost, optical alignment, imaging depth, and stability in the clocking circuit. This work introduces an optimized numerical k-sampling method to replace the additional k-clock hardware. Using this method, we can realize high axial resolution (4.9-µm full-width-half-maximum, in air) and low roll-off (2.3 dB loss) over a 4-mm imaging depth. The high axial resolution and sensitivity achieved by this simple numerical method can reveal anatomic and microvascular structures with structural OCT and OCTA in both macular and deeper tissues, including the lamina cribrosa, suggesting its usefulness in imaging retinopathy and optic neuropathy.

Development of high-performance point-of-care aqueous VEGF detection system and proof-of-concept validation in RVO patients

OBJECTIVES

To develop a sensitive point-of-care testing (POCT) aqueous vascular endothelial growth factor (VEGF) detection system, and assess its role for predicting the response to anti-VEGF treatment in macular edema secondary to retinal vein occlusion (RVO-ME) patients.

METHODS

An automatic point-of-care aqueous humor Magnetic Particle Chemiluminescence Enzyme Immuno-Assay (MPCLEIA) VEGF detection system was developed. The predictive values of aqueous cytokine levels, in combination with imaging parameters, on anatomical treatment response (ATR, the relative central macular thickness change [ΔCMT/bl-CMT]) were analyzed.

RESULTS

The automatic MPCLEIA system was able to provide results in 45 min with only 20 μL sample. Among the 57 eyes with available pre- and post-treatment evaluation, ATR significantly correlated with levels of interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1 (MCP-1) and VEGF measured by Luminex xMAP platform, and VEGF measured by MPCLEIA. Optimal cut-off values for these biomarkers were 13.26 ng/L, 23.57 ng/L, 1,110.12 ng/L, 105.52 ng/L, and 85.39 ng/L, respectively. Univariate analysis showed significant associations between ATR category (good response if ATR≤-25 % or poor response otherwise) and IL-6, IL-8, MCP-1, VEGF-xMAP, and VEGF-MPCLEIA (p<0.05). Multivariate logistic regression revealed that ATR category was significantly associated with aqueous VEGF-MPCLEIA (p=0.006) and baseline(bl)-CMT (p=0.008). Receiver operating characteristics analysis yielded an AUC of 0.959 for the regression model combining VEGF-MPCLEIA and bl-CMT, for predicting ATR category.

CONCLUSIONS

Our novel MPCLEIA-based automatic VEGF detection system enables accurate POCT of aqueous VEGF, which shows promise in predicting the treatment response of RVO-ME to anti-VEGF agents when combined with bl-CMT.

Vision-related quality of life in patients with retinal vein occlusion

PURPOSE

This study aims to assess the vision-related quality of life in patients with retinal vein occlusion (RVO) among those referred to Labbafinejad Medical Center and Imam Hossein Hospital between 2019 and 2021.

METHODS

This comparative study included 37 eligible patients diagnosed with various types of RVO, with an average age of 61 ± 9. To ensure data validity, we included 74 age- and sex-matched healthy individuals. Only cases with a definitive diagnosis of RVO, confirmed by two retina specialists (ND and RN), were included. We assessed the vision-related quality of life of our participants using the National Eye Institute Visual Functioning Questionnaire-25 (NEI-VFQ-25). All participants underwent interviews.

RESULTS

In our study, we examined the vision-related quality of life in different subgroups of RVO patients. Overall, RVO patients had a significantly lower total VRQoL score compared to healthy individuals (P < 0.001), except in the subscale analysis of specific factors such as ocular pain, color vision, and driving, where no statistically significant difference was observed. A statistically significant difference was found in the comparison of subgroups, indicating lower VRQoL in central retinal vein occlusion (CRVO) patients (P = 0.010). Furthermore, a significant correlation was observed between lower VRQoL and decreased vision (P = 0.009) as well as longer disease duration (P = 0.011).

CONCLUSION

Retinal vein occlusion can significantly reduce vision-related quality of life, particularly in more severe cases.

Recurrence of macular edema in patients with branch retinal vein occlusion: a proteomic study

BACKGROUND

Branch retinal vein occlusion (BRVO) is a common retinal vascular disease leading to severe vision loss and blindness. This study aimed to investigate and reveal the pathophysiological mechanisms underlying macular edema (ME) recurrence in patients with BRVO through a proteomic approach.

METHODS

We detected proteins in the aqueous humor of 14 untreated, four refractory, and four post-operative patients with BRVO-ME and 12 age-matched cataract controls using four-dimensional label-free proteomic and bioinformatics analyses.

RESULTS

In total, 84 proteins exhibited significant differential expression between the BRVO and control samples (fold change [FC] ≥ 1.2 and adjusted p-value < 0.05). Compared to the control group, 43 and 41 proteins were upregulated and downregulated, respectively, in the BRVO group. These proteins were involved in cell adhesion, visual perception, retina homeostasis, and platelet activation. Several significantly enriched signaling pathways included complement and coagulation cascades and platelet activation. In the protein-protein interaction networks generated using the search tool for retrieval of interacting genes (STRING), the fibrinogen alpha chain and fibrinogen beta chain constituted a tightly connected cluster. Many common protein expression trends, such as the fibrinogen alpha chain and fibrinogen beta chain, were observed in both the recurrent and refractory groups. Differentially expressed proteins in the two groups were involved in complement activation, acute-phase response, platelet activation, and platelet aggregation. Important signaling pathways include the complement and coagulation cascades, and platelet activation. Protein-protein interaction analysis suggested that the fibrinogen alpha chain and fibrinogen beta chain constituted a tightly connected cluster. The expression of some differentially expressed proteins shared by the BRVO and the recurrent and refractory groups was reversed in the post-operative group.

CONCLUSIONS

Our study is the first to analyze the proteomics of recurrent, refractory, and post-operative groups treated for BRVO-ME, and may potentially provide novel therapeutic interventions for the recurrence of ME.

Branch retinal vein occlusion treated with anti-VEGF: to switch or not to switch?

OBJECTIVE

To evaluate visual outcomes after switching from bevacizumab to ranibizumab or aflibercept in patients with macular edema (ME) secondary to branch retinal vein occlusion (BRVO).

DESIGN

A retrospective, multi-center, observational study.

PARTICIPANTS

Patients diagnosed with BRVO and were treated with at least 3 bevacizumab injections, before anti VEGF switch.

METHODS

The follow-up period was 36 months, and the primary study outcomes assessed changes in best corrected visual acuity (BCVA) after anti VEGF switch.

RESULTS

A total of 263 eyes of 263 patients with a mean age of 71.5 ± 11.2 years of which 50% were of male gender met the inclusion criteria. Of them, 175 eyes did not undergo switch, whereas 88 eyes underwent anti-VEGF switch. There was not a significant difference in mean age (p = 0.634) and gender (p = 0.269) between the groups. Baseline BCVA of the no-switch group was 0.47 ± 0.43 logMAR (20/59 Snellen) versus 0.6 ± 0.49 logMAR (20/79 Snellen) (p = 0.031) in the switch group, and at 36-months it was 0.41 ± 0.39 (20/51 Snellen) logMAR versus 0.54 ± 0.49 logMAR (20/69 Snellen) (p = 0.035), respectively. The difference between the rate of change in BCVA per year was insignificant between groups (p = 0.414). In multivariate analysis, baseline BCVA was the single significant predictor for switch (beta 0.137, p = 0.035). Patients with more than one anti-VEGF switch suffer from decrease in BCVA.

CONCLUSIONS

Worse baseline BCVA is a significant predictor for anti-VEGF switch execution, though the switch has no significant impact on the change in BCVA over time. Multiple anti-VEGF switch is not recommended.

Association of sodium-glucose cotransporter-2 inhibitors and the risk of retinal vascular occlusion: A real-world retrospective cohort study in Taiwan

AIMS

Sodium-glucose cotransporter-2 inhibitors (SGLT2is) are proposed to alleviate the development of inflammatory eye diseases. However, the association between SGLT2i and retinal vascular occlusion remains unclear. Therefore, this study aims to explore the effects of SGLT2i on the incidence of retinal vascular occlusion.

MATERIALS AND METHODS

This retrospective cohort study analysed electronic medical records data from the largest multi-institutional database in Taiwan. Individuals who initiated SGLT2is and dipeptidyl peptidase 4 inhibitors (DPP4is) between 2016 and 2019 were included in our analysis. To conduct a homogenous comparison, inverse probability of treatment weighting with propensity scoring was employed. The primary outcome was retinal vascular occlusion, and the secondary outcomes were retinal vascular occlusion-related complications (macular oedema, vitreous haemorrhage, and tractional retinal detachment) and conditions requiring vitreoretinal intervention (intravitreal injection, retinal laser therapy, and vitrectomy).

RESULTS

In total, 12,074 SGLT2i users and 39,318 DPP4i users were included. The incidence rate of retinal vascular occlusion in the SGLT2i and DPP4i groups was 1.2 (95% confidence interval [CI], 0.9-1.4) and 1.6 (95% CI, 1.3-1.8) events per 1000 person-years, respectively, which yielded a subdistribution hazard ratio (SHR) of 0.74 (95% CI, 0.55-0.99). Similar risk reductions were observed in the retinal vascular occlusion-related complications (SHR, 0.76; 95% CI, 0.69-0.84) and conditions requiring vitreoretinal intervention (SHR, 0.84; 95% CI, 0.77-0.94).

CONCLUSIONS

In this multi-institutional study in Taiwan, SGLT2i use was associated with a reduced risk of retinal vascular occlusion. Further prospective studies are required to ascertain this association.

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

Purpose

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).

Methods

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.

Results

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.

Conclusions

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.

Patterns of anti-vascular endothelial growth factor treatment for chorioretinal vascular diseases: Analysis of a nationwide claims database in Japan

BACKGROUND

Although intravitreal anti-vascular endothelial growth factor therapy is currently considered the first-line treatment for chorioretinal vascular diseases in Japan, information regarding its treatment pattern is scarce. This study investigated the patterns of anti-vascular endothelial growth factor treatment for chorioretinal vascular diseases.

METHODS

A health insurance claims database from acute care hospitals was used to estimate treatment intervals and continuation and drop-out rates regarding the anti-vascular endothelial growth factor. Patients aged ≥50 years diagnosed with neovascular age-related macular degeneration or aged ≥18 years diagnosed with diabetic macular edema or retinal vein occlusion were analyzed.

RESULTS

Data were included for 76,535, 49,704, and 37,681 patients with neovascular age-related macular degeneration, diabetic macular edema, and retinal vein occlusion, respectively; exactly 8,111, 2,283, and 6,896 received the treatment, respectively. The mean and median interval ranges during the maintenance phase by treatment initiation year were 94-100 and 73-80, 111-120 and 98-102, and 97-103 and 87-93 days for neovascular age-related macular degeneration, diabetic macular edema, and retinal vein occlusion, respectively, without any trend over time. A tendency to increase the treatment continuation rate was indicated in later years by Kaplan-Meier curves. The drop-out rate in the treatment initiation year (2016) was 32% from 63% (2009), 53% from 69% (2014), and 36% from 47% (2013) for neovascular age-related macular degeneration, diabetic macular edema, and retinal vein occlusion, respectively.

CONCLUSIONS

For all these diseases, the treatment intervals did not change remarkably, and a tendency toward improved treatment continuation was suggested.

Applications of deep learning for detecting ophthalmic diseases with ultrawide-field fundus images

AIM

To summarize the application of deep learning in detecting ophthalmic disease with ultrawide-field fundus images and analyze the advantages, limitations, and possible solutions common to all tasks.

METHODS

We searched three academic databases, including PubMed, Web of Science, and Ovid, with the date of August 2022. We matched and screened according to the target keywords and publication year and retrieved a total of 4358 research papers according to the keywords, of which 23 studies were retrieved on applying deep learning in diagnosing ophthalmic disease with ultrawide-field images.

RESULTS

Deep learning in ultrawide-field images can detect various ophthalmic diseases and achieve great performance, including diabetic retinopathy, glaucoma, age-related macular degeneration, retinal vein occlusions, retinal detachment, and other peripheral retinal diseases. Compared to fundus images, the ultrawide-field fundus scanning laser ophthalmoscopy enables the capture of the ocular fundus up to 200° in a single exposure, which can observe more areas of the retina.

CONCLUSION

The combination of ultrawide-field fundus images and artificial intelligence will achieve great performance in diagnosing multiple ophthalmic diseases in the future.

Intelligent diagnosis of retinal vein occlusion based on color fundus photographs

AIM

To develop an artificial intelligence (AI) diagnosis model based on deep learning (DL) algorithm to diagnose different types of retinal vein occlusion (RVO) by recognizing color fundus photographs (CFPs).

METHODS

Totally 914 CFPs of healthy people and patients with RVO were collected as experimental data sets, and used to train, verify and test the diagnostic model of RVO. All the images were divided into four categories [normal, central retinal vein occlusion (CRVO), branch retinal vein occlusion (BRVO), and macular retinal vein occlusion (MRVO)] by three fundus disease experts. Swin Transformer was used to build the RVO diagnosis model, and different types of RVO diagnosis experiments were conducted. The model's performance was compared to that of the experts.

RESULTS

The accuracy of the model in the diagnosis of normal, CRVO, BRVO, and MRVO reached 1.000, 0.978, 0.957, and 0.978; the specificity reached 1.000, 0.986, 0.982, and 0.976; the sensitivity reached 1.000, 0.955, 0.917, and 1.000; the F1-Sore reached 1.000, 0.955 0.943, and 0.887 respectively. In addition, the area under curve of normal, CRVO, BRVO, and MRVO diagnosed by the diagnostic model were 1.000, 0.900, 0.959 and 0.970, respectively. The diagnostic results were highly consistent with those of fundus disease experts, and the diagnostic performance was superior.

CONCLUSION

The diagnostic model developed in this study can well diagnose different types of RVO, effectively relieve the work pressure of clinicians, and provide help for the follow-up clinical diagnosis and treatment of RVO patients.

Interpretable Detection of Diabetic Retinopathy, Retinal Vein Occlusion, Age-Related Macular Degeneration, and Other Fundus Conditions

Diabetic retinopathy (DR), retinal vein occlusion (RVO), and age-related macular degeneration (AMD) pose significant global health challenges, often resulting in vision impairment and blindness. Automatic detection of these conditions is crucial, particularly in underserved rural areas with limited access to ophthalmic services. Despite remarkable advancements in artificial intelligence, especially convolutional neural networks (CNNs), their complexity can make interpretation difficult. In this study, we curated a dataset consisting of 15,089 color fundus photographs (CFPs) obtained from 8110 patients who underwent fundus fluorescein angiography (FFA) examination. The primary objective was to construct integrated models that merge CNNs with an attention mechanism. These models were designed for a hierarchical multilabel classification task, focusing on the detection of DR, RVO, AMD, and other fundus conditions. Furthermore, our approach extended to the detailed classification of DR, RVO, and AMD according to their respective subclasses. We employed a methodology that entails the translation of diagnostic information obtained from FFA results into CFPs. Our investigation focused on evaluating the models' ability to achieve precise diagnoses solely based on CFPs. Remarkably, our models showcased improvements across diverse fundus conditions, with the ConvNeXt-base + attention model standing out for its exceptional performance. The ConvNeXt-base + attention model achieved remarkable metrics, including an area under the receiver operating characteristic curve (AUC) of 0.943, a referable F1 score of 0.870, and a Cohen's kappa of 0.778 for DR detection. For RVO, it attained an AUC of 0.960, a referable F1 score of 0.854, and a Cohen's kappa of 0.819. Furthermore, in AMD detection, the model achieved an AUC of 0.959, an F1 score of 0.727, and a Cohen's kappa of 0.686. Impressively, the model demonstrated proficiency in subclassifying RVO and AMD, showcasing commendable sensitivity and specificity. Moreover, our models enhanced interpretability by visualizing attention weights on fundus images, aiding in the identification of disease findings. These outcomes underscore the substantial impact of our models in advancing the detection of DR, RVO, and AMD, offering the potential for improved patient outcomes and positively influencing the healthcare landscape.

Real-World Management of Macular Edema Secondary to Retinal Vein Occlusion with Intravitreal Aflibercept: 24-month Results from the AURIGA Observational Study

INTRODUCTION

AURIGA is the largest real-world study to date to evaluate intravitreal aflibercept (IVT-AFL) treatment of diabetic macular edema or macular edema secondary to retinal vein occlusion (RVO) in routine clinical practice. Here, we report the 24-month outcomes in the RVO cohort from France, Germany, Italy, and Taiwan.

METHODS

AURIGA (NCT03161912) was a prospective observational study. Eligible patients with RVO were enrolled for whom the decision to treat with IVT-AFL had already been made by the attending physician. Patients were treated with IVT-AFL for up to 24 months at physician discretion according to local practice. The primary endpoint was mean change in visual acuity (VA; Early Treatment Diabetic Retinopathy Study [ETDRS] letters) from baseline to month (M) 12. All statistical analyses were descriptive.

RESULTS

In 554 treatment-naïve and 65 previously treated patients with RVO, the respective mean (95% confidence interval) change in VA from baseline was + 12.5 (10.8, 14.3) and + 7.9 (3.3, 12.6) letters by M12 and + 11.4 (9.4, 13.3) and + 4.4 (- 0.6, 9.5) letters by M24 (baseline mean ± standard deviation: 51.0 ± 21.9 and 51.9 ± 20.4 letters); 44.0% of treatment-naïve and 27.9% of previously treated patients reported ≥ 15-letter gains by M24. By M24, the mean change in central retinal thickness from baseline was - 247 (- 267, - 227) µm in treatment-naïve patients and - 147 (- 192, - 102) µm in previously treated patients. From baseline to M6, M12, and M24, treatment-naïve patients received a total of 4.0 ± 1.3, 5.5 ± 2.5, and 6.9 ± 4.2 injections, respectively, and previously treated patients received 3.8 ± 1.5, 5.0 ± 2.2, and 6.3 ± 3.7 injections, respectively. The safety profile of IVT-AFL was consistent with that of previous studies.

CONCLUSIONS

In AURIGA, patients with RVO experienced clinically relevant functional and anatomic improvements following IVT-AFL treatment in routine clinical practice. These improvements were largely maintained in treatment-naïve patients over the 24-month study despite the decreasing treatment frequency, suggesting long-term durability of IVT-AFL treatment outcomes. Infographic available for this article.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03161912 (May 19, 2017). INFOGRAPHIC.

[Internistic clarification of retinal vascular occlusions]

Retinal vascular occlusions require close cooperation of different medical disciplines to ensure optimal care of the affected patients. The medical clarification between arterial and venous occlusions is comparable but in the case of retinal arterial occlusions it should be carried out immediately. The most important associated diagnoses are arterial hypertension, diabetes mellitus, dyslipidemia, and atrial fibrillation. In younger patients and in the absence of risk factors, a search for rarer causes should be carried out giant cell arteritis in particular should be excluded. In both types of occlusions a causative glaucoma must also be considered.

Acute Kidney Injury from Intravitreal Anti-vascular Endothelial Growth Factor Drugs: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Several observational studies have reported acute kidney injury from intravitreal anti-vascular endothelial growth factor (anti-VEGF) drugs for retinal diseases. However, systematic reviews and meta-analyses of randomized controlled trials on this critical topic are scant.

OBJECTIVE

To evaluate acute kidney injury risk associated with intravitreal anti-VEGF drugs in patients with retinal diseases.

METHODS

We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials on 12 July, 2023, and included randomized controlled trials reporting acute kidney injury between anti-VEGF drugs (e.g., aflibercept, bevacizumab, brolucizumab, and ranibizumab) and controls for retinal diseases (e.g., age-related macular degeneration, polypoidal choroidal vasculopathy, diabetic retinopathy/diabetic macular edema, retinal vein occlusion, and myopic choroidal neovascularization). Data were synthesized by a fixed-effects model for pooling odds ratios (ORs) using the Peto method.

RESULTS

We included 13 randomized controlled trials (four and nine trials for aflibercept and ranibizumab, respectively) with a total of 4282 participants. The meta-analysis indicated intravitreal anti-VEGF drugs did not increase the acute kidney injury risk, compared with controls (odds ratio [OR]: 1.00, 95% confidence interval [CI] 0.49-2.04, I2: 0%), and no differences in the acute kidney injury risk were observed between different anti-VEGF drugs (OR: 1.10, 95% CI 0.27-4.43, I2: 0% for aflibercept; OR: 0.97, 95% CI 0.42-2.22, I2: 0% for ranibizumab) and between different retinal diseases (OR: 4.61, 95% CI 0.07-284.13, I2: not applicable for age-related macular degeneration; OR: 0.90, 95% CI 0.42-1.93, I2: 0% for diabetic retinopathy/diabetic macular edema; OR: 1.57, 95% CI 0.16-15.88, I2: 0% for retinal vein occlusion).

CONCLUSIONS

Intravitreal anti-VEGF drugs were not associated with an acute kidney injury risk, regardless of which anti-VEGF drugs (aflibercept or ranibizumab) or retinal diseases (age-related macular degeneration, diabetic retinopathy/diabetic macular edema, or retinal vein occlusion) were involved.

SYSTEMATIC REVIEW PROTOCOL REGISTRATION

PROSPERO CRD42021267854.

Microbiome and Retinal Vascular Diseases

The gut microbiome consists of more than a thousand different microbes and their associated genes and microbial metabolites. It influences various host metabolic pathways and is therefore important for homeostasis. In recent years, its influence on health and disease has been extensively researched. Dysbiosis, or imbalance in the gut microbiome, is associated with several diseases. Consequent chronic inflammation may lead to or promote inflammatory bowel disease, obesity, diabetes mellitus, atherosclerosis, alcoholic and non-alcoholic liver disease, cirrhosis, hepatocellular carcinoma, and other diseases. The pathogenesis of the three most common retinal vascular diseases, diabetic retinopathy, retinal vein occlusion, and retinal artery occlusion, may also be influenced by an altered microbiome and associated risk factors such as diabetes mellitus, atherosclerosis, hypertension, and obesity. Direct cause-effect relationships remain less well understood. A potential prevention or treatment modality for these diseases could be targeting and modulating the individual's gut microbiome.

Sleep-disordered breathing is related to retinal vein occlusion: A meta-analysis

BACKGROUND

Previous studies suggest that sleep-disordered breathing (SDB) may be a potential risk factor of retinal vein occlusion (RVO). We conducted a meta-analysis to systematically explore the relationship between RVO and SDB.

METHODS

Observational studies assessing the relationship between SDB and RVO were retrieved by searches of electronic databases including the PubMed, Embase, Web of Science, China National Knowledge Infrastructure, and Wan Fang databases from database inception to August 9, 2023. In consideration of intra-study heterogeneity, a random-effects model was adopted to combine the results.

RESULTS

Seven studies (1 retrospective cohort and 6 case-control studies) were included in this meta-analysis, and among 36,628 adults included in those studies, 6452 (17.6%) had SDB. The combined results indicated that SDB was associated with RVO [risk ratio (RR): 1.92, 95% confidence interval (CI): 1.60-2.30, P < .001] with no significant heterogeneity (I2 = 0%). Subgroup analyses showed consistent relationships between SDB and any RVO (RR: 1.73, 95% CI: 1.13-2.28, P < .001), central RVO (RR: 2.20, 95% CI: 1.57-3.08, P < .001), and branch RVO (RR: 1.85, 95% CI: 1.15-2.99, P = .01). Moreover, the relationship was consistent among patients with mild (RR: 1.82, 95% CI: 1.32-2.53, P < .001), moderate (RR: 2.17, 95% CI: 1.65-2.85, P < .001), and severe SDB (RR: 2.66, 95% CI: 1.96-3.62, P < .001). The association was consistent in studies that adjusted for age and sex (RR: 2.17, 95% CI: 1.50-3.13, P < .001), and in studies with additional adjustment for comorbidities (RR: 1.78, 95% CI: 1.42-2.25, P < .001).

CONCLUSION

SDB is associated with RVO in adults.

An Analysis of Optical Coherence Tomography Angiography (OCT-A) Perfusion Density Maps in Patients Treated for Retinal Vein Occlusion with Intravitreal Aflibercept

AIM

The primary goal of this study was to evaluate the reduction in non-perfusion area and improvement in blood flow as well as the reduction in retinal edema on optical coherence tomography angiography (OCT-A) in patients with retinal vein occlusion treated with 2 mg intravitreal injections of aflibercept.

MATERIAL AND METHODS

Fifty eyes of nine patients with central retinal vein occlusion (CRVO) and sixteen patients with branch retinal vein occlusion (BRVO), aged 50 to 75 years, were collectively analyzed as retinal vein occlusion (RVO). The following parameters were analyzed: superficial vessel density (VDSF), deep vessel density (VDD), flow area in the outer retina (FAOR), choriocapillaris flow area (FACC), non-flow area (NFA) and the foveal avascular zone (FAZ).

RESULTS

OCT-A revealed a reduction in macular edema. The most significant change in central retinal thickness (CRT) was observed between measurement timepoint "5" and the baseline (46%). The non-flow area was also reduced. Following a significant decrease in superficial vessel density 30 days after the first dose of aflibercept, a non-significant increase was noted at the subsequent timepoints. An increase was also found in deep vessel density and choriocapillaris flow area. Improvements in the above OCT-A parameters resulted in increased retinal blood flow and improved visual acuity.

CONCLUSIONS

Patients with retinal vein occlusion treated with 2 mg aflibercept exhibited reduced macular edema and FAZ, increased vessel density, improved blood flow, and better visual acuity.

Automatic Diagnosis of Different Types of Retinal Vein Occlusion Based on Fundus Images

Retinal vein occlusion (RVO) is the second common cause of blindness following diabetic retinopathy. The manual screening of fundus images to detect RVO is time consuming. Deep-learning techniques have been used for screening RVO due to their outstanding performance in many applications. However, unlike other images, medical images have smaller lesions, which require a more elaborate approach. To provide patients with an accurate diagnosis, followed by timely and effective treatment, we developed an intelligent method for automatic RVO screening on fundus images. Swin Transformer learns the hierarchy of low-to high-level features like the convolutional neural network. However, Swin Transformer extracts features from fundus images through attention modules, which pay more attention to the interrelationship between the features and each other. The model is more universal, does not rely entirely on the data itself, and focuses not only on local information but has a diffusion mechanism from local to global. To suppress overfitting, we adopt a regularization strategy, label smoothing, which uses one-hot to add noise to reduce the weight of the categories of true sample labels when calculating the loss function. The choice of different models using a 5-fold cross-validation on our own datasets indicates that Swin Transformer performs better. The accuracy of classifying all datasets is 98.75 ± 0.000, and the accuracy of identifying MRVO, CRVO, BRVO, and normal, using the method proposed in the paper, is 94.49 ± 0.094, 99.98 ± 0.015, 98.88 ± 0.08, and 99.42 ± 0.012, respectively. The method will be useful to diagnose RVO and help decide grade through fundus images, which has the potency to provide patients with further diagnosis and treatment.