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 1.000,0.9550.943,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.

Dexamethasone implant for refractory macular edema secondary to diabetic retinopathy and retinal vein occlusion

AIM:To evaluate the efficacy,timing of retreatment and safety of dexamethasone(DEX)implant on macular edema(ME)secondary to diabetic retinopathy(DME)and retinal vein occlusion(RVO-ME)patients who were refractory to anti-vascular endothelial growth factor(VEGF)treatment.METHODS:This retrospective study included 37 eyes received at least one DEX implant treatment for DME or RVO-ME between January 1,2019,and January 1,2023.These refractory DME and RVO-ME cases received at least 5 anti-VEGF injections and failure to gain more than 5 letters or a significant reduction in central retinal thickness(CRT).The best corrected visual acuity(BCVA)and CRT were measured at baseline,and at 1,3,4 and 6mo post-DEX implant injection.Adverse events such as elevated intraocular pressure(IOP)and cataract were recorded.RESULTS:For RVO cases(n=22),there was a significant increase in BCVA from 0.27±0.19 to 0.35±0.20 at 6mo post-DEX injection(P<0.05)and CRT decreased from 472.1±90.6 to 240.5±39.0μm at 6mo(P<0.0001).DME cases(n=15)experienced an improvement in BCVA from 0.26±0.15 to 0.43±0.20 at 6mo post-DEX implant injection(P=0.0098),with CRT reducing from 445.7±55.7 to 271.7±34.1μm at 6mo(P<0.0001).Elevated IOP occurred in 45.9% of patients but was well-controlled with topical medications.No cases of cataract or other adverse events were reported.CONCLUSION:DEX implants effectively improve BCVA and reduce CRT in refractory DME and RVO-ME.Further research with larger cohorts and longer follow-up periods is needed to confirm these findings and assess long-term outcomes.

Comparative Quantitative Analysis of Retinal Superficial Capillary Plexus in Patients with Retinal Vein Occlusion and Unaffected Fellow Eyes

Purpose: To evaluate optical coherence tomography angiography (OCT-A) data obtained from the superficial retinal capillary plexus of patients with retinal vein occlusion and comparative analysis with data registered from unaffected fellow eyes. Methods: The examined patients were classified into 2 groups: group 1—eyes with established retinal vein occlusion (n = 29) and group 2—unaffected fellow eyes of patients with retinal vein occlusion (n = 24). The scanning protocol “Angiography 3 × 3 mm” of Zeiss Cirrus HD-OCT 6000, AngioPlex Metrix was used to evaluate the retinal superficial capillary plexus. The analyzed parameters were vascular density and perfusion density, as well as the area, perimeter, and circularity of the foveolar avascular zone (FAZ). Results: The comparative analysis of FAZ parameters at the superficial capillary plexus (SCP) between group 1 (eyes with retinal vein occlusion) and group 2 (unaffected fellow eyes) showed significant results for the three parameters, respectively area (p = 0.003), perimeter (p ≤ 0.001), and circularity (p = 0.011) of FAZ. The comparative analysis of the vascular network at SCP in patients with diagnosed retinal vein occlusion and unaffected fellow eyes showed significant results for vascular density (VD) in the central (p = 0.038) and inner (p ≤ 0.001) zones as well as total VD (p ≤ 0.001) were statistically significant. Moreover, the results obtained in the study of vascular perfusion (VP) indicated significant results in the inner zone (p ≤ 0.001) and total VP (p = 0.001). Vascular perfusion in the central zone (p = 0.116) was the only parameter not to meet significant results. Conclusion: The current study observed a significant enlargement of the FAZ and loss of its circularity, along with a reduction in vascular network parameters at the superficial retinal capillary plexus level.

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

AIM：To evaluate the potential role of hyperreflective foci（HF） as a prognostic indicator of visual outcome in patients with macular edema（ME） due to retinal vein occlusion（RVO）.METHODS：We retrospectively reviewed 50 eyes of 50 patients with ME due to ischemic central retinal vein occlusion（CRVO）,non-ischemic CRVO and branch retinal vein occlusion（BRVO） who were treated with anti-vascular endothelial growth factor（anti-VEGF） at Beijing Tongren Eye Center from January 2013 to July 2016.All patients underwent best-corrected visual acuity（BCVA）,spectral domain optical coherence tomography（SD-OCT） at baseline and follow-up.Such factors were evaluated and compared among three groups as baseline and final BCVA,central retinal thickness（CRT）,external limiting membrane（ELM） status and the numbers of HF in different position.Multiple linear regression analysis was employed to analyze the relationship between baseline HF and final BCVA.Changes of HF before and after treatment were evaluated too.RESULTS：Among three groups,HF could be located in each retinal layers,as well as in vitreous cavity.The mean HF in outer retinal layer（ORL） at baseline was 5.29±8.48 in ischemic CRVO with intact ELM,1.93±2.76 in non-ischemic CRVO,and 1.75±2.05 in BRVO.With disrupted ELM,the mean HF in ORL increased.There was statistically difference of HF in ORL between intact and disrupted ELM.The numbers of HF in ORL were associated with poor visual outcome among three groups.However,HF in inner retinal layer（IRL） and vitreous cavity were not associated with poor visual outcome.Meanwhile,the baseline HF in ORL and vitreous cavity reduced significantly in nonischemic CRVO and BRVO after anti-VEGF treatment.CONCLUSION：The numbers of HF in ORL are prognostic factors associated with the final BCVA in patients with ME due to RVO after anti-VEGF treatment.

Intravitreal anti-VEGF agents, oral glucocorticoids, and laser photocoagulation combination therapy for macular edema secondary to retinal vein occlusion: preliminary report

AIM： To evaluate the efficacy and safety of combined anti-vascular endothelial growth factor （VEGF） agents, oral glucocorticoid, and laser photocoagulation therapy for macular edema （ME） secondary to retinal vein occlusion （RVO）. METHODS： This study included 16 eyes of 16 patients with RVO-associated ME. Patients were initially treated with oral prednisone and an intravitreal anti-VEGF agent. Two weeks later, patients underwent standard laser photocoagulation. Best-corrected visual acuity （BCVA）, central retinal thickness （CRT）, and retinal vessel oxygenation were examined over 12mo. RESULTS： Patients received 1.43＋0.81 anti-VEGF injections. Mean baseline and 12-month IogMAR BCVA were 0.96±0.51 （20/178） and 0.31±0.88 （20/40）, respectively, in eyes with central retinal vein occlusion （CRVO） （P〈0.00）, and 1.02±0.45 （201209） and 0.60±0.49 （20/80）, respectively, in eyes with branch retinal vein occlusion （BRVO） （P〈0.00）. At 12mo, CRT had significantly decreased in eyes with CRVO （P〈0.00） and BRVO （P〈0.00）. Venous oxygen saturation had significantly increased in eyes with CRVO （P〈0.00） and BRVO （P〈0.00）. No examined parameters were significantly different between the 2 RVO groups. No serious adverse effects occurred. CONCLUSION： Anti-VEGF, glucocorticoid, and photocoagulation combination therapy improves visual outcome, prolongs therapeutic effect, and reduces the number of intravitreal injections in eyes with RVO- associated ME.

Study of retinal vessel oxygen saturation in ischemic and non-ischemic branch retinal vein occlusion

AIM：To explore how oxygen saturation in retinal blood vessels is altered in ischemic and non-ischemic branch retinal vein occlusion（BRVO）.·METHODS：Fifty BRVO eyes were divided into ischemic（=26）and non-ischemic（=24）groups,based on fundus fluorescein angiography.Healthy individuals（=52 and=48,respectively）were also recruited as controls for the two groups.The mean oxygen saturations of the occluded vessels and central vessels were measured by oximetry in the BRVO and control groups.·R ESULTS：In the ischemic BRVO group,the occluded arterioles oxygen saturation（Sa O2-A,106.0%±14.3%）,instead of the occluded venule oxygen saturation（Sa O2-V,60.8%±9.4%）,showed increases when compared with those in the same quadrant vessels（Sa O2-A,86.1%±16.5%）in the contralateral eyes（〈0.05）.The oxygen saturations of the central vessels showed similar trends with those of the occluded vessels.In the non-ischemic BRVO group,the occluded and central Sa O2-V and Sa O2-A showed no significant changes.In both the ischemic and non-ischemic BRVOs,the central Sa O2-A was significantly increased when compared to healthy individuals.·CONCLUSION：Obvious changes in the occluded and central Sa O2-A were found in the ischemic BRVO group,indicating that disorders of oxygen metabolism in the arterioles may participate in the pathogenesis of ischemic BRVO.

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

AIM： To compare three initial monthly intravitreal ranibizumab（IVR） injections followed by pro re nata（PRN） dosing with one initial monthly IVR injections followed by PRN dosing for macular edema（ME） secondary to branch retinal vein occlusion（BRVO）.METHODS： Forty-two eyes of 42 patients who had IVR injections for BRVO were retrospectively studied. Eighteen eyes received 1 initial IVR injection（1＋PRN group） and 24 eyes received 3 monthly IVR injections（3＋PRN）. At 1, 3, 6 and 12mo; spectral-domain optical coherence tomography（SD-OCT） was performed. Central macular thickness（CMT）, the integrity of the external limiting membrane（ELM）, the presence of subretinal fluid, cyst size, the presence of inner segment/outer segment（IS/OS） defect were determined.RESULTS： At baseline the mean CMT was 521.3±153.2 μm in the 3＋PRN group while it was 438.1±162.4 μm in 1＋PRN group. At the final visit, mean CMT was 278.3±87.8 μm in the 3＋PRN group and 285.2±74.2 μm in the 1＋PRN group（P=0.079）. The changes in CMT over the entire study period were also comparable in both groups（243±160 μm in the 3＋PRN group, and 152.9±175.3 μm in the 1＋PRN group; P=0.090）. At baseline, best-corrected visual acuity（BCVA） was 0.92±0.60 logarithm of the minimal angle of resolution（logMAR） in the 3＋PRN group, while it was 0.72±0.46 logMAR in the 1＋PRN group. Final BCVA was 0.42±0.55 logMAR in the 3＋PRN group and 0.38±0.50 logMAR in the 1＋PRN group（P=0.979）. Additionally, the BCVA changes from baseline to final visit were not significantly different（-0.50±0.45 logMAR in the 3＋PRN group, and-0.33±0.39 logMAR in the 1＋PRN group; P=0.255）.CONCLUSION： No significant differences in the anatomical or functional results are found between 3＋PRN and 1＋PRN regimens in the patients receiving ranibizumab for ME secondary to BRVO. Intact IS/OS and baseline BCVA are good predictor of the visual gain, while baseline CMT is a good predictor of the anatomical gain.

Intravitreal injection of bevacizumab alone or with triamcinolone acetonide for treatment of macular edema caused by central retinal vein occlusion

AIM: To compare the efficacy and safety of intravitreal bevacizumab alone versus bevacizumab combined with triamcinolone acetonide in eyes with macular edema caused by central retinal vein occlusion (CRVO) in Chinese patients. METHODS: Seventy-five eyes of 75 patients were enrolled in this prospective, randomized, consecutive study. Thirty-six patients in group 1 were treated with an intravitreal injection of bevacizumab (1.25mg/0.05mL), and 39 patients in group 2 were treated with intravitreal bevacizumab (1.25mg/0.05mL) combined with triamcinolone acetonide (2mg/0.05mL). The main outcomes of the mean best corrected visual acuity (BCVA), central retinal thickness (CRT), and intraocular pressure (IOP) were measured. RESULTS: In group 1, the mean BCVA improved from 37.78 +/- 6.14 (baseline) to 48.06 +/- 3.86, 46.48 +/- 4.77 and 44.18 +/- 5.78 at four, six and twelve weeks post-injection, respectively (P<0.01, P=0.03, P=0.04). In group 2, the mean BCVA improved from 35.92 +/- 6.20 (baseline) to 50.69 +/- 4.22, 48.76 +/- 5.59 and 45.70 +/- 6.56 at the same time points (P<0.01 each). However, there was no significant differences in the mean BCVA (F=0.043, P=0.836) and CRT (F=0.374, P=0.544) between these two groups. During the follow-up, five patients in group 1 and six patients in group 2 with high IOP were controlled with anti-glaucoma drugs. CONCLUSION: Intravitreal injection of bevacizumab alone or combined with triamcinolone acetonide has a short beneficial effect in Chinese patients with macular edema caused by CRVO, but there is no significant difference between the two groups.

Effects of two different doses of intravitreal bevacizumab on subfoveal choroidal thickness and retinal vessel diameter in branch retinal vein occlusion

AIM： To investigate the effects of two different doses of intravitreal bevacizumab on subfoveal choroidal thickness （SFChT） and retinal vessel diameter in patients with branch retinal vein occlusion. METHODS： An interventional, restrospective study of 41 eyes of 41 patients who had completed 12mo of follow-up, divided into group 1 （1.25 mg of bevacizumab, 21 eyes of 21 patients） and group 2 （2.5 mg of bevacizumab, 20 eyes of 21 patients）. Complete ophthalmic examination, fluorescein angiography, enhanced depth imaging optical coherence tomography and measurement of retinal vessel diameter with IVAN software were performed at baseline and follow-up. RESULTS： The SFChT changed from 279.1 （165-431） μm at baseline to 277.0 （149-413） μm at 12mo in group 1 （P= 0.086）, and from 301.4 （212-483） μm to 300.3 （199-514） μm in group 2 （P=0.076）. The central retinal arteriolar equivalent （CRAE） changed from 128.8 ±11.2 μm at baseline to 134.5±8.4 μm at 12mo in group 1, and from 134.6±9.0 μm to 131.4±12.7 μm in group 2 （P =0.767）. The central retinal venular equivalent （CRVE） changed from 204.1±24.4 μm at baseline to 196.3±28.2 μm at 12mo in group 1, and from 205.8±16.3 μm to 194.8±18.2 μm in group 2 （P=0.019）. The mean central macular thickness （P〈0.05） and average best-corrected visual acuity （BCVA; P〈0.05） improved in both groups CONCLUSION： Changes in the SFChT are not statistically significant and not different according to the doses of bevacizumab. The CRAE did not show significant change, however, the CRVE showed significant decrease regardless of the dose.

Establishing an experimental rat model of photo-dynamically-induced retinal vein occlusion using erythrosin B

AIM:To develop a reliable,reproducible rat model of retinal vein occlusion(RVO)with a novel photosensitizer(erythrosin B)and study the cellular responses in the retina.METHODS:Central and branch RVOs were created in adult male rats via photochemically-induced ischemia.Retinal changes were monitored via color fundus photography and fluorescein angiography at 1 and 3h,and 1,4,7,14,and 21d after irradiation.Tissue slices were evaluated histopathologically.Retinal ganglion cell survival at different times after RVO induction was quantified by nuclear density count.Retinal thickness was also observed.RESULTS:For all rats in both the central and branch RVO groups,blood flow ceased immediately after laser irradiation and retinal edema was evident at one hour.The retinal detachment rate was 100%at 3h and developed into bullous retinal detachment within 24h.Retinal hemorrhages were not observed until 24h.Clearance of the occluded veins at 7d was observed by fluorescein angiography.Disease manifestation in the central RVO eyes was more severe than in the branch RVO group.A remarkable reduction in the ganglion cell count and retinal thickness was observed in the central RVO group by 21d,whereas moderate changes occurred in the branch RVO group.CONCLUSION:Rat RVO created by photochemicallyinduced ischemia using erythrosin B is a reproducible and reliable animal model for mimicking the key features of human RVO.However,considering the 100%rate ofretinal detachment,this animal model is more suitable for studying RVO with chronic retinal detachment.

Choroidal thickness measurements with optical coherence tomography in branch retinal vein occlusion

AIM： To evaluate central macular thickness（CMT） and mean choroidal thickness（MCT） in eyes with branch retinal vein occlusion（BRVO）, before and after ranibizumab treatment using spectral domain-optical coherence tomography（SD-OCT）.·METHODS： Forty-two patients with unilateral BRVO and macular edema were included in this study. There were 25 men and 17 women. Using SD-OCT, choroidal thickness was measured at 500 μm intervals up to 1500μm temporal and nasal to the fovea. MCT was calculated based on the average of the 7 locations. All the eyes with BRVO were treated with intravitreal ranibizumab（0.5 mg/0.05 m L）. Comparisons between the BRVO and fellow eyes were analyzed using Mann-Whitney U test. Preinjection and post-injection measurements were analyzed using Wilcoxon test and repeated measure analysis.· RESULTS： At baseline, there was a significant difference between the BRVO and fellow eyes in MCT[BRVO eyes 245（165-330） μm, fellow eyes 229（157-327） μm]and CMT [BRVO eyes 463（266-899） μm, fellow eyes 235（148-378） μm（P =0.041, 0.0001, respectively）]. Following treatment, CMT [295（141-558） μm] and MCT [229（157-329） μm] decreased significantly compared to the baseline measurements（P =0.001, 0.006, respectively）.Also BCVA（log MAR） improved significantly（P=0.0001） in the BRVO eyes following treatment. After treatment CMT[BRVO eyes 295（141-558） μm, fellow eyes 234（157-351） μm]and MCT [BRVO eyes 229（157-329） μm, fellow eyes 233（162-286） μm] values did not reveal any significant difference in BRVO eyes and fellow eyes（P=0.051, 0.824,respectively）.· CONCLUSION： In eyes with BRVO, CMT and MCT values are greater than the fellow eyes, and decrease significantly following ranibizumab injection.

Comparison of intravitreal bevacizumab with intravitreal triamcinolone acetonide for treatment of cystoid macular edema secondary to retinal vein occlusion : a Meta-analysis

AIMTo compare the effects of intravitreal injection of bevacizumab (IVB) with intravitreal triamcinolone acetonide (IVTA) on the treatment of cystoid macular edema (CME) secondary to retinal vein occlusion (RVO).METHODSA literature search was conducted using PubMed, the Cochrane Central Register of Controlled Trials, Web of Science and the Chinese Biomedical Database. The comparison was divided into two groups, group 1 conducted comparison in branch RVO (BRVO) or central RVO (CRVO), group 2 conducted comparison in ischemic-RVO or nonischemic-RVO. Pooled mean differences (MDs) for changes in visual acuity (VA), central macular thickness (CMT) and intraocular pressure (IOP) were calculated in groups at 4, 12 and 24wk after treatment respectively.RESULTSEight studies comparing the efficacy of IVB with IVTA were included in the Meta-analysis. In group 1, in BRVO, significant difference was shown on the comparison of CMT at 24wk (MD, -45.66; 95% CI, -76.03 to -15.28; P=0.003), IVB was effective on BRVO for at least 24wk; no significant differences were found in the comparison of VA at each time points (P&#x0003e;0.05 respectively). In CRVO, no significant differences were found in the comparison of VA or CMT between IVB and IVTA at each time points (P&#x0003e;0.05, respectively). In group 2, in ischemic-RVO, significant differences were shown in the comparison of VA (MD, -0.28; 95% CI, -0.42 to -0.14; P&#x0003c;0.0001) and CMT (MD, -86.50; 95% CI, -151.18 to -22.43; P=0.008) at 24wk; In nonischemic-RVO, no significant differences were demonstrated in the comparison of VA or CMT between IVB and IVTA at each time points (P&#x0003e;0.05, respectively). The occurrence of high IOP was much lower in IVB group.CONCLUSIONThis Meta-analysis suggested that IVB was effective in decreasing CMT in BRVO for at least 24wk, IVB is more effective on improving VA and reducing CMT in ischemic-RVO. IVB is more promising on RVO than IVTA.

Anti-VEGF reduces inflammatory features in macular edema secondary to retinal vein occlusion

AIM: To investigate the anti-inflammatory effect of intravitreal injection of anti-vascular endothelial growth factor(anti-VEGF) in patients with macular edema secondary to retinal vein occlusion(RVO-ME).METHODS: Twenty-eight eyes from twenty-eight treatment-na?ve patients(14 males and 14 females) with RVO-ME were included in this retrospective study.The retinal vein occlusion(RVO) was comprised of both central retinal vein occlusion(CRVO,n=14) and branch retinal vein occlusion(BRVO,n=14).Intravitreal injection of anti-VEGF reagents were administered monthly for three consecutive months,in which 18 patients were injected with ranibizumab and 10 patients were injected with conbercept.All eyes were imaged with optical coherence tomography angiography(OCTA) at baseline and 1wk after monthly intravitreal anti-VEGF injection.The visual acuity(VA),central macular thickness(CMT),the number of hyperreflective foci(HRF) recognized as an inflammatory sign in OCT images,and non-perfusion area(NPA),were compared before and after anti-VEGF treatments.RESULTS: The mean interval between baseline and follow-up was 29.4±0.79(range,27-48)d.Compared with the baseline,the VA improved(log MAR 1.5±0.1 vs 0.8±0.1,P<0.05) and CMT decreased(460±34.0 μm vs 268.8±12.0 μm,P<0.05),significantly,after antiVEGF treatment.The number of HRF was decreased significantly(76.5±4.8 vs 47.8±4.3,P<0.05) after antiVEGF treatment.CONCLUSION: Anti-VEGF therapy is effective in treating RVO-ME.The mechanisms for the decreased HRF and the reduction of NPA by anti-VEGF therapy merits further exploration.

Comparison of intravitreal ranibizumab and bevacizumab for the treatment of macular edema secondary to retinal vein occlusion

AIMTo compare the efficacy of ranibizumab and bevacizumab for macular edema due to retinal vein occlusion (RVO).

Comparison of intravitreal injection of conbercept and triamcinolone acetonide for macular edema secondary to branch retinal vein occlusion

AIM:To compare the safety and efficacy of the intravitreal injection of conbercept(IVC)and triamcinolone acetonide(IVTA)for macular edema(ME)secondary to branch retinal vein occlusion(BRVO).METHODS:A prospective,randomized clinical study.Patients with ME secondary to BRVO were randomly assigned to either IVC group or IVTA group at a ratio of 2:1 and a 12-month follow-up was performed.The efficacy outcome measures included the mean changes and differences in best corrected visual acuity(BCVA)and the central retinal thickness(CRT).The safety profiles and the mean retreatment intervals were also compared.RESULTS:There was no statistically significant difference of baseline between the two groups(IVC group,n=36;IVTA group,n=17).At 12mof the BCVA letters improved by 27.31±18.36 in the IVC group,and 13.53±11.37 in the IVTA group(P=0.0004).CRT reduction was 253.33±163.69 and 150.24±134.32 pm,respectively(P=0.0034).The mean BCVA in the IVC group was superior to that of the IVTA group for months 6-12(P<0.01).The mean CRT at 9 and 12mo were thinner in the IVC group compared to the IVTA group(P<0.01).The mean retreatment interval in the IVC group was longer than that in the IVTA group(97.40±36.27d vs 68.71±36.38d,P=0.0030).One eye in the IVC group and seven eyes in the IVTA group developed elevated intraocular pressure(IOP;P=0.0012).The proportion of eyes with cataract new-onset or progression were 19.44%in the IVC group and 64.71%in the IVTA group(P=0.0012).CONCLUSION:IVC could maintain or improve BCVA and reduce CRT for a longer time and have longer retreatment interval than IVTA.In addition,patients treated with IVTA are more susceptible to IOP elevation and cataract progression.

10-year fundus tessellation progression and retinal vein occlusion

AIM： To access the 10-year fundus tessellation progression in patients with retinal vein occlusion. METHODS： The Beijing Eye Study 2001/2011 is a populationbased longitudinal study. The study participants underwent a detailed physical and ophthalmic examination. Degree of fundus tessellation was graded by using fundus photographs of the macula and optic disc. Progression of fundus tessellation was calculated by fundus tessellation degree of 2011 minus degree of 2001. Fundus photographs were used for assessment of retinal vein occlusion. RESULTS： The Beijing Eye Study included 4403 subjects in 2001, 3468 subjects was repeated in 2011. Assessment of retinal vein obstruction and fundus tessellation progression were available for 2462 subjects（71.0%）, with 66 subjects fulfilled the diagnosis of retinal vein occlusion. Of the 66 participants, 59 participants with unilateral branch retinal vein occlusion, 5 participants with unilateral central retinal vein occlusion, 1 participant with bilateral branch retinal vein occlusion, and 1 participant with branch retinal vein occlusion in one eye and central retinal vein occlusion in the other eye. Mean degree of peripapillary fundus tessellation progression were significantly higher in the whole retinal vein occlusion group（0.33±0.39, P〈0.001）, central retinal vein occlusion group（0.71±0.8, P=0.025） and branch retinal vein occlusion group（0.29±0.34, P=0.006） than the control group（0.20±0.26）. After adjustment for age, prevalence of tilted disc, change of best corrected visual acuity, axial length, progression of peripapillary fundus tessellation was associated with the presence of retinal vein occlusion（P=0.004; regression coefficient B, 0.094; 95%CI, 0.029, 0.158; standardized coefficient B, 0.056）. As a corollary, after adjusting for smoking duration, systolic blood pressure, anterior corneal curvature, prevalence of RVO was associated with more peripapillary fundus tessellation progression（P〈0.001; regression coefficient B： 1.257; OR： 3.517; 95%CI： 1.777, 6.958）. CONCLUSION： Peripapillary fundus tessellation progresses faster in individuals with retinal vein occlusion. This may reflect the thinning and hypoperfusion of choroid in patients with retinal vein occlusion.

Ocular hypertension in patients with central/hemicentral retinal vein occlusions： cumulative prevalence and management

AIM： To prospectively evaluate the cumulative prevalence and the management of ocular hypertension（OH） in patients with unilateral acute central/hemicentral retinal vein occlusions（C/HCRVOs） over the course of 3 y. METHODS： The study included 57 patients with unilateral acute C/HCRVOs. All patients underwent a comprehensive ophthalmological examination of both eyes. OH associated with C/HCRVO in patients showing a score 〉5% for the risk of conversion to primary open angle glaucoma（POAG） was treated with OH medication. The treatment aimed for a decrease in intraocular pressure（IOP） to 〈21 mm Hg with a 〉22% reduction from the initial values. The cumulative prevalence of OH and the effectiveness of treatment assessed by the cumulative prevalence of conversion from OH to POAG, were estimated. RESULTS： Fifteen patients had OH associated with C/HCRVOs, the cumulative prevalence of OH was 29.4%（95% confidence interval, 16.9-41.9）. The mean value of the risk score of OH conversion to POAG for the 5 subsequent years was 11.7%±5.4%. The IOP significantly decreased from 25.67±2.16 mm Hg to 18.73±2.96 mm Hg. None of the OH patients converted to POAG during the follow-up period. CONCLUSION： The increased cumulative prevalence of OH in C/HCRVO patients indicates that OH is a risk factor for the appearance of venous occlusion. Patients with OH associated with C/HCRVO must be considered to be at high risk for conversion to POAG. Treatment with OH medications prevented conversion to POAG during the 3-year follow-up.

Efficacy of conbercept after switching from bevacizumab/ranibizumab in eyes of macular edema secondary to central retinal vein occlusion

AIM: To explore the efficacy of conbercept after switching from bevacizumab/ranibizumab in eyes of central retinal vein occlusion(CRVO) through optical coherence tomography angiography(OCTA). METHODS: Patients with prior treatment of a minimum of three consecutive intravitreal injections of either bevacizumab or ranibizumab, followed by injection of conbercept, were recruited. The minimal follow-up period after switching was 12 mo. Central retinal thickness(CRT), best-corrected visual acuity(BCVA), the interval of injections was reviewed. Perfusion density(PD) and vascular length density(VLD) of superficial and deep capillary plexus were acquired from OCTA images before and after switching. RESULTS: Twenty-four eyes were included. CRT significantly decreased from 460.71±153.23 μm(before switching) to 283.92±38.27 μm at the end of follow-up(P<0.001). However, BCVA gained to some extent(from 0.98±0.33 to 0.76±0.42 log MAR) but the difference was not significant(P=0.070). After switching to conbercept the injection interval extended from 5.2±2.3 wk to 8.3±3.9 wk(P=0.012). At the end of follow-up, PD of deep retinal layer decreased significantly compared with before switching(from 34.62%±5.27% to 33.26%±5.82%, P=0.016), similar result was found in VLD of deep retinal layer but not in PD or VLD in superficial layer.CONCLUSION: In cases of refractory macular edema secondary to CRVO, switching to conbercept improves macular thickness and extends interval of injection. Retinal microvasculature cannot improve with treatment of conbercept.

Comparison of efficacy of conbercept,aflibercept,and ranibizumab ophthalmic injection in the treatment of macular edema caused by retinal vein occlusion:a Meta-analysis

AIM:To evaluate and compare the anatomical and functional outcomes and negative effects of the three anti-vascular endothelial growth factor(VEGF)drugs in the treatment of macular edema(ME)due to retinal vein occlusion(RVO)based on the evidence pooled from current clinical trials and observational studies.METHODS:A systematic literature search was conducted on nine online databases from inception until April 30,2022.The main endpoints were best corrected visual acuity(BCVA),central macular thickness(CMT),and adverse events(AEs).Cumulative Meta-analysis was conducted to synthesize the outcomes of the drugs.The retrieved data were analyzed using Stata software(version 12.0).RESULTS:A total of 20 studies comprising 1674 eyes met the inclusion criteria to the Meta-analysis.It was observed that conbercept and aflibercept had better visual acuity effects compared with ranibizumab at 1mo[weight mean difference(WMD)=-0.03,P=0.001;WMD=-0.05,P=0.019],but the effects were not different from that of ranibizumab at 6mo.Moreover,there was not statistically significant dif ference in the propor tion of patients gaining≥15 letters at 12-24mo between aflibercept and ranibizumab[odds ratio(OR)=1.16,P=0.427].Conbercept had higher mean CMT change effects at 1mo(WMD=-14.43,P=0.014)and 6mo(WMD=-35.63,P≤0.001)compared with ranibizumab.Meanwhile,the mean CMT change effects at 1mo(WMD=-10.14,P=0.170),6mo(WMD=-26.98,P=0.140)and 12-24mo(WMD=-12.34,P=0.071)were comparable among the groups.Similarly,AEs were not significantly different among the treatments(OR=0.75,P=0.305;OR=1.04,P=0.89).The stability of effect size of mean BCVA and CMT improved with the increase in sample size.Aflibercept and conbercept required fewer injections compared with ranibizumab.CONCLUSION:This is the first study to evaluate the efficacy and AEs of intravitreal administration of conbercept,ranibizumab,and aflibercept in the treatment of RVOME.Intravitreal aflibercept or conbercept results in better mean change in vision and CMT reduction compared with ranibizumab.Conbercept can be considered to be a promising and innovative drug with good anti-VEGF effects.

Aqueous levels of erythropoietin in acute retinal vein occlusion with macular edema

AIM:To investigate the aqueous erythropoietin(EPO)levels and associated factors in patients with acute retinal vein occlusion(RVO).METHODS:The aqueous EPO level was measured in patients with macular edema(ME)secondary to acute branched retinal vein occlusion(BRVO)or central retinal vein occlusion(CRVO).Aqueous fluid from cataract patients served as the control.We also evaluated whether aqueous level of EPO was associated with factors such as serum EPO level,non-perfusion area,central macular thickness(CMT),and arterio-venous(AV)transit timeRESULTS:Twenty-seven RVO patients(16 BRVO,11CRVO)and 9 control subjects were enrolled in the study.The aqueous EPO level(mU/mL)was higher in RVO(68.2±54.3)than that in the control subjects(12.9±5.9).More specifically,the aqueous EPO level was higher in CRVO(118.9±52.1)than that in BRVO(33.3±10.8).However,no differences were found in serum EPO levels among three groups.CMT in RVO patients had a positive correlation with the aqueous EPO level(r=0.66).Also,in terms of non-perfusion area,the aqueous EPO levels were more elevated in the ischemic subgroup than in the non-ischemic subgroup in both BRVO and CRVO.CONCLUSION:Aqueous EPO levels are elevated in patients with macular edema secondary to recent onset RVO.Patients with CRVO have higher EPO levels than those with BRVO.The aqueous EPO level in RVO has a positive correlation with CMT and is associated with non-perfusion area.These results suggest that the aqueous EPO level could be associated with retinal ischemia and may be involved in the pathogenesis of macular edema secondary to RVO.