Optical coherence tomography angiography for macular microvessels in ischemic branch retinal vein occlusion treated with conbercept:predictive factors for the prognosis

AIM:To evaluate the predicative factors of visual prognosis using optical coherence tomography angiography(OCTA)in ischemic branch retinal vein occlusion(BRVO)patients with macular edema(ME)after anti-vascular endothelial growth factor(VEGF)treatment.METHODS:In this retrospective analysis,data from 60 patients(60 eyes)with a definite diagnosis of ischemic BRVO with ME by fundus fluorescein angiography(FFA)were studied.The eyes with ME according to spectral domain optical coherence tomography(SD-OCT)underwent intravitreal conbercept(IVC)and 3+pro re nata(PRN)regimen.The injection times were recorded.Two weeks after injection,fundus laser photocoagulation was performed in the non-perfusion area of the retina.The patients were followed up once a month for 6mo.The bestcorrected visual acuity(BCVA),foveal avascular zone(FAZ),and A-circularity index(AI),at 6mo and the baseline were compared.RESULTS:All patients showed significant improvement in BCVA from 0.82±0.32 to 0.39±0.11 logMAR(P<0.001).The mean central macular thickness(CMT)significantly decreased from 476.22±163.54 to 298.66±109.23μm.Both the FAZ area and AI at 6mo were significantly higher than those at the baseline:the FAZ area increased(0.38±0.02 vs 0.39±0.02 mm^(2),P<0.05);the AI increased(1.27±0.02 vs 1.31±0.01,P=0.000).The baseline BCVA showed a significantly positive correlation with the baseline FAZ area,FAZ perimeter(PERIM)and AI,final visual gain(FVG)and injection times,respectively(P<0.001).FVG showed a significantly negative correlation with the FAZ area,PERIM,AI and injection times,but a significantly positive correlation with vessel densities(VDs)300μm area around FAZ(FD-300;P<0.001).Injection times was positively correlated with the baseline FAZ area,and AI,but inversely correlated with the baseline FD-300(P<0.001).However macular ischemia was noted in 5 cases during follow-up.CONCLUSION:Using OCTA to observe macular ischemia and quantify parameters can better predict the final visual prognosis of patients before treatment.The changes in FAZ parameters may influence the visual prognosis and injection times.

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.

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 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.

Peripheral retinal non-perfusion and treatment response in branch retinal vein occlusion

AIM： To evaluate the association between the size of peripheral retinal non-perfusion and the number of intravitreal ranibizumab injections in patients with treatment-naive branch retinal vein occlusion （BRVO） and macular edema. METHODS： A total of 53 patients with treatment-naive BRVO and macular edema were included. Each patient underwent a full ophthalmologic examination including optical coherence tomography （OCT） imaging and ultra wide-field fluorescein angiography （UWFA）. Monthly intravitreal ranibizumab injections were applied according to the recommendations of the German Ophthalmological Society. Two independent, masked graders quantified the areas of peripheral retinal non-perfusion. RESULTS： Intravitreal injections improved bestcorrected visual acuity （BCVA） significantly from 22.23± 16.33 Early Treatment of Diabetic Retinopathy Study （ETDRS） letters to 36.23 ±15.19 letters （P〈0.001）, and mean central subfield thickness significantly reduced from 387±115 pm to 321±115 μm （P=0.01）. Mean number of intravitreal ranibizumab injections was 3.61±1.56. The size of retinal non-perfusion correlated significantly with the number of intravitreal ranibizumab injections （R= 0.724, P〈0.001）. CONCLUSION： Peripheral retinal non-perfusion in patients with BRVO associates significantly with intravitreal ranibizumab injections in patients with BRVO and macular edema.

Visual acuity after intravitreal ranibizumab with and without laser therapy in the treatment of macular edema due to branch retinal vein occlusion:a 12-month retrospective analysis

AIM:To identify factors contributing to visual improvement after treatment of macular edema(ME)secondary to branch retinal vein occlusion(BRVO),and to assess the interaction between laser therapy and intravitreal ranibizumab(IVR).METHODS:We retrospectively reviewed the medical records of patients who had been treated for BRVO-related ME at our hospital.Records were traceable for at least 12 mo,and evaluated factors included age,sex,medical history,smoking history,treatment methods,foveal hemorrhage,and change in visual acuity.Treatments included laser therapy,IVR,sub-Tenon’s capsule injection of triamcinolone(STTA),a combination,or no intervention.Multivariate logistic regression analysis and interaction terms were used to assess the clinical efficacy of the treatments,and odds ratios(OR)and 95%confidence intervals(CI)were calculated.RESULTS:Seventy-three patients(34 men,39 women;73 eyes)with a mean age of 69.4±12.1 y were included.Patients who underwent IVR monotherapy,laser monotherapy,and STTA+laser had significantly higher best corrected visual acuity at 12 mo compared to baseline(P<0.001,<0.001,and 0.019,respectively).Logistic regression analysis without interaction terms found that IVR was a significant visual acuity recovery factor(adjusted OR:3.89,95%CI:1.25-12.1,P=0.019).Adjusted OR using an interaction model by logistic regression was 16.6(95%CI:2.54-108.47,P=0.003)with IVR treatment,and 8.25(95%CI:1.34-50.57,P=0.023)with laser treatment.No interaction was observed(adjusted OR:0.07,95%CI:0.01-0.75,P=0.029).CONCLUSION:IVR contributes to improvements in visual acuity at 12 mo in ME secondary to BRVO.No interaction is observed between laser therapy and IVR treatments.

Efficacy of intravitreal conbercept injection on short-and long-term macular edema in branch retinal vein occlusion

AIM: To observe the best-corrected visual acuity(BCVA) and central foveal thickness(CFT) repeatedly after the intravitreal injection of conbercept(IVC) for treating cystoid macular edema(CME) in branch retinal vein occlusion(BRVO) and explore the relationship between the duration of CME and visual outcome.METHODS: Subgroup analysis was performed to compare short-term(within 90 d of CME onset) and longterm(over 90 d of CME onset) macular edema in BRVO.After an initial IVC, a pro re nata(PRN) strategy was performed according to the recurrence of CFT or decrease of BCVA.Analysis of variance using repeated measurements, statistical analysis following indicators including BCVA and CFT collected at baseline and 1, 3, and 6 mo after IVC.RESULTS: Among the 60 cases included in this retrospective study, 36 were short-term CME, and 24 were long-term CME.There were statistical significances between and within groups of the BCVAs at different time points(P<0.001).The interaction was found between group and time(P=0.006), indicating the difference in the speed of BCVA improvement between groups.In particular, the improvement speed of BCVA in the short-term CME group was faster than that in the long-term CME group.There were significant differences between and with groups of the CFT at different time points(P<0.001).However, the interaction between group and time in relation to CFT had no significant differences(P=0.59).CONCLUSION: IVC treatment for CME following BRVO is effective and safe.The duration of CME before treatment is a significant predictor of the visual outcomes of patients with BRVO.The improvement of vision might be faster with early IVC treatment than with delayed treatment.

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.

Efficacy of intravitreal injection of ranibizumab in the treatment of macular edema secondary to non-ischemic branch retinal vein occlusion

Objective: To observe the efficacy of intravitreal injection of ranibizumab in the treatment of macular edema(ME) secondary to non-ischemic branch retinal vein occlusion (BRVO). Methods: The clinical data of 27 patients (27 eyes) with macular edema secondary to non-ischemic BRVO were diagnosed by ophthalmology in Chongqing University Center Hospital from May 2018 to April 2019, selected as the experimental group, and 20 cases (20 eyes) of normal people as the control group. For the experimental group, before and after treatment, 1wk, 1mo, 2mo, 3mo and 6mo were used to observe the uncorrected visual acuity(UCVA),best corrected visual acuity (BCVA), intraocular pressure (IOP), central retinal thickness (CRT) macular center volume (MCV) and EN FACE images. Subjects in the normal control group were examined by optical coherence tomography (OCT) for CRT and CMV at 1wk, 1mo, 2mo, 3mo and 6mo on the day of and after enrollment. Results: The mean age of patients in the experimental group was (67.37±8.63) years old and the times of Intravitreal injection was (3.26 ±0.59) times. The successful rate of treatment was 85.19%. There was no significant difference in IOP between pre-treatment and 1wk, 1mo, 2mo, 3mo and 6mo (P > 0.05). 1wk, 1mo, 2mo, 3mo and 6mo BCVA were significantly higher than those before treatment (P < 0.0001). The levels of CRT and CMV at 1wk, 1mo, 2mo, 3mo and 6mo after treatment were significantly lower than those before treatment (P <0.01). Compared with the normal control group, the CRT and CMV of the experimental group before and after treatment showed statistically significant differences in 1wk, 1mo, 2mo and 3mo (P <0.05). There was no statistically significant difference in 6mo CRT and CMV after treatment (P>0.05). EN FACE showed that 1wk, 1mo, 2mo, 3mo and 6mo macular thickness decreased gradually, retinal edema subsided, cystoid changes disappeared, and the interlamellar structure of the ellipsoid zone gradually recovered after intravitreal injection of ranibizumab. Conclusion: Intravitreal injection of ranibizumab in the treatment of non-ischemic BRVO secondary ME has significant efficacy, EN FACE is an effective means to assess the severity, treatment and prognosis of patients.

Branch Retinal Vein Occlusion and Its Management

The natural course of Branch Retinal Vein Occlusion is determined by the site and completeness of the occlusion, the integrity of arterial perfusion to the affected sector and the efficiency of the developing collateral circulation. Most patients with tributary vein occlusion have some capillary fall out and microvascular incompetence in the distribution of the affected retina and vision is significantly compromised in over 50% of patients who have either chronic macular oedema or ischemia involving the...

Treatment controversies in a rare case of a simultaneous branch retinal artery and vein occlusion secondary to hyperhomocysteinemia and hypertension

Dear Editor,Combined vascular occlusions involving retinal arteries and veins have been reported in the past. Combined occlusion of the central retinal vein （CRVO） and artery （CRAO）is well described;. Cilioretinal artery occlusion along with CRVO is frequently reported and is well characterized;.

Deep-learning classifier with ultrawide-field fundus ophthalmoscopy for detecting branch retinal vein occlusion

AIM: To investigate and compare the efficacy of two machine-learning technologies with deep-learning(DL) and support vector machine(SVM) for the detection of branch retinal vein occlusion(BRVO) using ultrawide-field fundus images. METHODS: This study included 237 images from 236 patients with BRVO with a mean±standard deviation of age 66.3±10.6 y and 229 images from 176 non-BRVO healthy subjects with a mean age of 64.9±9.4 y. Training was conducted using a deep convolutional neural network using ultrawide-field fundus images to construct the DL model. The sensitivity, specificity, positive predictive value(PPV), negative predictive value(NPV) and area under the curve(AUC) were calculated to compare the diagnostic abilities of the DL and SVM models. RESULTS: For the DL model, the sensitivity, specificity, PPV, NPV and AUC for diagnosing BRVO was 94.0%(95%CI: 93.8%-98.8%), 97.0%(95%CI: 89.7%-96.4%), 96.5%(95%CI: 94.3%-98.7%), 93.2%(95%CI: 90.5%-96.0%) and 0.976(95%CI: 0.960-0.993), respectively. In contrast, for the SVM model, these values were 80.5%(95%CI: 77.8%-87.9%), 84.3%(95%CI: 75.8%-86.1%), 83.5%(95%CI: 78.4%-88.6%), 75.2%(95%CI: 72.1%-78.3%) and 0.857(95%CI: 0.811-0.903), respectively. The DL model outperformed the SVM model in all the aforementioned parameters(P<0.001). CONCLUSION: These results indicate that the combination of the DL model and ultrawide-field fundus ophthalmoscopy may distinguish between healthy and BRVO eyes with a high level of accuracy. The proposed combination may be used for automatically diagnosing BRVO in patients residing in remote areas lacking access to an ophthalmic medical center.

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.

Retinal vessel oxygen saturation in healthy subjects and early branch retinal vein occlusion

AIM： To measure the retinal oxygen saturation in healthy subjects and early branch retinal vein occlusion（BRVO） in Chinese population.METHODS： The retinal vessel oxygen saturation of the healthy subjects and BRVO patients were measured by a noninvasive retinal oximeter（Oxymap ehf.,Reykjavik,Iceland）.RESULTS： The study included 22 patients with unilateral BRVO（mean age： 55.1±8.8y） in the study group and 91 healthy participants（mean age： 37.5±14.0y） in the control group.In the healthy individuals,mean arterial and venous oxygen saturation were significantly（P〈0.001）higher in the superior nasal quadrant（98.5%±10.1%and 57.3%±8.7%,respectively） than in the inferior nasal quadrant（94.2%±9.0% and 54.1%±9.6%,respectively）,followed by the superior temporal quadrant（89.1%±10.1%and 51.9%±8.9%,respectively） and the inferior temporal quadrant（86.4%±9.4% and 46.6%±9.6%,respectively）.In patients with ischemic BRVO,arterial oxymetric values were significantly higher and venous measurements significantly lower for the affected vessel（107.5%±9.7% and46.4%±14.2%,respectively） than the unaffected vessel in the same eye（99.2%±12.2% and 55.5%±7.9%,respectively）and as compared to the vessel in the unaffected fellow eye（93.1%±6.9% and 55.7%±6.8%）（P=0.005 and P=0.02,respectively）.In the patients with non-ischemic BRVO,mean venous oxygen saturation was lower in the affected vein（39.8%±12.2%） than in the unaffected vessels of the same eye（50.8%±10.5%） and in the fellow eye（58.21%±5.7%）（P=0.03）.Mean arterial oxygen saturation did not differ significantly（P=0.42） between all three groups.CONCLUSION： In patients with BRVO,the venous oxygen saturation in the affected vessels is decreased potentially due to decreased blood velocity and flow.Interestingly,thearterial oxygen saturation in eyes with ischemic BRVO is increased in the affected arteries.

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.

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.

Sectoral changes of the peripapillary choroidal thickness in patients with unilateral branch retinal vein occlusion

AIM: To investigate sectoral changes in the mean peripapillary choroidal thickness(PCT) in patients with unilateral branch retinal vein occlusion(BRVO). METHODS: This retrospective, interventional study included 41 patients with acute, unilateral BRVO without macular edema. All patients completed at least a 6-month follow-up period. The PCT was measured at eight locations(temporal, superotemporal, superior, superonasal, nasal, inferonasal, inferior, and inferotemporal). In addition to calculating the average of all locations, the peripapillary choroidal area was divided into four sectors: superior(average of superotemporal PCT, superior PCT, and superonasal PCT), temporal, inferior(average of inferotemporal PCT, inferior PCT, and inferonasal PCT), and nasal. RESULTS: In the BRVO-affected eyes, the mean PCT was 177.7±69.8 μm(range, 70.1-396.0 μm) at baseline and 127.8±54.8 μm(range, 56.4-312.1 μm) at 6 mo(P<0.001). In the non-affected contralateral eyes, the mean PCT was 192.5±60.6 μm(range, 61.4-365.0 μm) at baseline and 165.9±61.1 μm(range, 56.8-326.8 μm) at 6 mo(P<0.001). In sectoral analysis, the mean PCT in each sector was significantly reduced in over 6 mo in the BRVO-affected eyes(all P<0.001). In the non-affected contralateral eyes, the mean PCT was not significantly changed in any sector over the 6-month follow-up period(superior sector, P=0.143; temporal sector, P=0.825; inferior sector, P=0.192; and nasal sector, P=0.599).CONCLUSION: Sectoral analysis shows that the mean PCTs in all sectors are reduced significantly over 6 mo in the BRVO-affected eyes, but not in the non-affected contralateral eyes.

Approved pharmacotherapy for macular edema secondary to branch retinal vein occlusion:A review of randomized controlled trials in dexamethasone implants,ranibizumab,and aflibercept

There are three approved pharmacotherapies for treating macular edema secondary to branch retinal vein occlusion(BRVO), including corticosteroids(dexamethasone implants) and anti-vascular endothelial growth factor(VEGF)(ranibizumab and aflibercept). They all show superior ability to improve vision and reduce macular thickness, comparing with sham injections or macular grid laser treatment. There is no severe ocular or systemic adverse reaction reported in studies associated with anti-VEGF for macular edema after BRVO. Intraocular pressure elevation and cataract aggravation should be addressed after intravitreal dexamethasone implants. Single intravitreal dexamethasone implant had effective duration as long as four to six months. Intravitreal anti-VEGF requires six monthly injections as loading doses, and then PRN regimen needed according to functional and anatomical changes. Ozurdex and ranibizumab reduce not only macular edema, but also the probability of retinal ischemia and neovascularization in patient s with BRVO. Prompt treatment with these agents can lead to a better outcome.

Wide‑field swept‑source OCT angiography of the periarterial capillary‑free zone before and after anti‑VEGF therapy for branch retinal vein occlusion

Background:The aim of the study was to investigate the changes in the periarterial capillary-free zone(paCFZ)after anti-vascular endothelial growth factor(VEGF)therapy in patients with branch retinal vein occlusion(BRVO)by widefield swept-source optical coherence tomography angiography(SS-OCTA)and assess their associations with clinical outcomes.Methods:In this retrospective observational study of 54 treatment-naive BRVO patients with macular edema,we reviewed the findings of 12×12 mm^(2)SS-OCTA at baseline,3,6,and 12 months after intravitreal ranibizumab injections.The paCFZ and major retinal artery areas were measured on SS-OCTA images.The paCFZ area to artery area(P/A)ratio was calculated.Results:The paCFZ areas and P/A ratios of first-and second-order arteries were significantly greater in BRVO eyes than in contralateral eyes(all P<0.01),but there were no differences in the first-and second-order artery areas(P=0.20 and 0.25,respectively).The paCFZ areas and P/A ratios decreased significantly at 3,6,and 12 months after anti-VEGF therapy(all P<0.01).The baseline P/A ratio was significantly correlated with the baseline best-corrected visual acuity(BCVA),central retinal thickness,and their improvements at 3,6,and 12 months(all P<0.05).Baseline BCVA and P/A ratios of first-and second-order arteries were independently associated with the final BCVA in multivariate linear regression.Conclusions:Wide-field SS-OCTA shows that anti-VEGF therapy can lead to a significant improvement in the paCFZ parameters in BRVO.Smaller baseline P/A ratios on SS-OCTA tend to predict better visual outcomes at 12 months after anti-VEGF therapy.