Aflibercept combined with triamcinolone acetonide in the treatment of diabetic macular edema:optical coherence tomography and optical coherence tomography angiography

AIM:To analyze the relationship between optical coherence tomography(OCT)and OCT angiography(OCTA)imaging in patients with diabetic macular edema(DME)who are treated with a combination of aflibercept and triamcinolone acetonide(TA).METHODS:A total of 76 eyes newly diagnosed DME were included in this study.They were randomly assigned to receive either aflibercept or a combination of aflibercept and TA.Injections once a month for a total of three injections.Central macular thickness(CMT),number of hyperreflective foci(HRF),height of subretinal fluid(SRF),and area of foveal avascular zone(FAZ)were evaluated using OCT and OCTA at baseline and after each monthly treatment.RESULTS:Both groups showed improvement in best corrected visual acuity(BCVA)and reduction in macular edema after treatment,and the difference in BCVA between the two groups was statistically significant after each treatment(P<0.05).The difference in CMT between the two groups was statistically significant after the first two injections(P<0.01),but not after the third injection(P=0.875).The number of HRF(1mo:7.41±8.25 vs 10.86±7.22,P=0.027;2mo:5.33±6.13 vs 9.12±8.61,P=0.034;3mo:3.58±3.00 vs 6.37±5.97,P=0.007)and height of SRF(1mo:82.39±39.12 vs 105.77±42.26μm,P=0.011;2mo:36.84±10.02 vs 83.59±37.78μm,P<0.01;3mo:11.57±3.29 vs 45.43±12.60μm,P<0.01)in combined group were statistically significant less than aflibercept group after each injection,while the area of FAZ showed no significant change before and after treatment in both groups.CONCLUSION:The combination therapy of aflibercept and TA shows more significant effects on DME eyes with decreased HRF and SRF.However,both aflibercept and combination therapy show no significant change in the area of FAZ.

Epiretinal membrane related vascular changes in diabetic eyes evaluated with optical coherence tomography angiography

AIM:To evaluate the retinochoroidal microvascular circulation and anatomical structure of diabetic and nondiabetic patients with epiretinal membrane(ERM)with the help of optical coherence tomography angiography(OCT-A)and compare them with healthy control subjects.METHODS:In this prospective,cross-sectional study,a total of 165 eyes were evaluated,including 50 eyes of patients with diabetic ERM,54 eyes of idiopathic ERM(iERM)patients,and 61 eyes of healthy controls.Macula and disc angiography was performed by OCT-A.Macular vessel density(VD)ratio was evaluated by dividing the VD of the foveal region by the VD of the parafoveal region.Statistical calculations were evaluated at the 95%confidence interval.RESULTS:Macula superficial VD values of ERM cases were lower than that in the control group,while foveal VD was higher in ERM cases.Macula deep VD values of ERM cases were lower in all quadrants,except the fovea.The width of the foveal avascular zone(FAZ)area was significantly lower in the ERM groups,and the FAZ width was lowest in iERM group.Macula superficial VD ratio was significantly higher in the ERM groups,but there was no significant difference between ERM groups.Macula deep VD ratio was significantly higher in the iERM group than in the control group.CONCLUSION:Diabetic and idiopathic ERMs differ in their mechanism of formation and clinical presentation,as well as their effect on retinal vascular structures.If the relationship of increase of retinal thickness with vascular integrity can be demonstrated with OCT-A,then,OCT-A can be used as a guide for ERM prognosis.

Optical coherence tomography angiography assessment of 577 nm laser effect on severe non-proliferative diabetic retinopathy with diabetic macular edema

AIM:To quantitatively evaluate the effect of the combined use of 577-nm subthreshold micropulse macular laser(SML)and multi-point mode pan retinal laser photocoagulation(PRP)on severe non-proliferative diabetic retinopathy(NPDR)with central-involved diabetic macular edema(CIDME)using optical coherence tomography angiography(OCTA).METHODS:In this observational clinical study,86 eyes of 86 NPDR patients with CIDME who underwent SML and PRP treatment were included.Images were obtained 1 d before laser and post-laser(1 d,1 wk,1,3,and 6 mo)using AngioV ue software 2.0.Best corrected visual acuity(BCVA,LogM AR),foveal avascular zone area(FAZ),choriocapillary flow area(Ch F),parafoveal vessel density(PVD),capillary density inside disc(CDD),peripapillary capillary density(PCD),macular ganglion cell complex thickness(m GCCT),central macular thickness(CMT),and subfoveal choroidal thickness(ChT)were compared between pre-and post-laser treatment.RESULTS:BCVA remained stable during 6 mo postlaser therapy(pre-laser vs 6 mo post-laser:0.53±0.21 vs 0.5±0.15,P>0.05).PVD,ChF,ChT,CMT,and mGCCT significantly increased 1 d post-laser therapy[pre-laser vs 1 d post-laser:superficial PVD(%),40.51±3.42 vs 42.43±4.68;deep PVD(%),42.66±3.67 vs 44.78±4.52;ChF,1.72±0.21 vs 1.9±0.12 mm^2;ChT,302.45±69.74 vs 319.38±70.93μm;CMT,301.65±110.78 vs 320.86±105.62μm;m GCCT,105.71±10.72 vs 115.46±9.64μm;P<0.05].However,PVD,ChF and ChT decreased to less than baseline level at 6 mo postlaser therapy(pre-laser vs 6 mo post-laser:superficial PVD(%),40.51±3.42 vs 36.32±4.19;deep PVD(%),42.66±3.67 vs 38.76±3.74;Ch F,1.72±0.21 vs 1.62±0.09 mm^2;Ch T,302.45±69.74 vs 289.61±67.55μm;P<0.05),whereas CMT and mG CCT decreased to baseline level at 6 mo postlaser therapy(CMT,301.65±110.78 vs 297.77±90.23μm;m GCCT,105.71±10.72 vs 107.05±11.81μm;P>0.05).Moreover,FAZ continuously increased while CDD and PCD continuously decreased in 6 mo after laser therapy.CMT and ChT had a significant positive correlation with ChF and PVD in most post-laser stages.CONCLUSION:During a 6-month follow-up period after combined use of SML and PRP therapy,BCVA remained stable and there was a decreased trend in macular edema.Blood flow increased at 1 d post-laser therapy and reduced at 6 mo post-laser therapy.

Is laser photocoagulation still effective in diabetic macular edema? Assessment with optical coherence tomography in Nepal

AIM: To find out the outcome of laser photocoagulation in clinically significant macular edema (CSME) by optical coherence tomography (OCT). · METHODS: It was a prospective, non-controlled, case series study enrolling 81 eyes of 64 patients with CSME between August 2008 and January 2010. All patients received modified grid photocoagulation with frequency doubled Nd: YAG laser. Each patient was evaluated in terms of best-corrected visual acuity (BCVA) and regression or progression of maculopathy after laser therapy at 1, 3 and 6 months. Spearman’s correlation test was used to show the correlation between BCVA and total macular volume (TMV). Analysis of variance (ANOVA) was used to compare among groups and independent t-test was used to compare in each group. · RESULTS: There is high correlation between BCVA and TMV (P ≤0.001). BCVA improved in 50.6%, remained static in 39.5 % and deteriorated in 9.9% patients after 6 month of treatment. The Baseline TMV (mean and SD) were 9.26±1.83, 10.4±2.38, 11.5±3.05, 8.89±0.75 and 9.47±1.98 mm3 for different OCT patterns, ST (sponge like thickening), CMO (cystoid macular edema), SFD (subfoveal detachment), VMIA (Vitreo macular interface abnormality) and average TMV respectively (P =0.04). After 6 months of laser treatment, the mean TMV decreased from 9.47±1.98mm3 to 8.77±1.31mm3(P =0.01). In ST there was significant decrease in TMV, P =0.01, Further within these groups at 6 months, they were significantly different, P =0.01. · CONCLUSION: OCT showed the different morphological variant of CSME while the response of treatment is different. TMV decreased the most and hence showed the improvement in vision after 6 months of laser treatment. In the era of Anti vascular endothelial growth factors (VEGFs), efficacy of laser seems to be in shadow but it is still first line of treatment in developing nation like Nepal where antiVEGFs may not be easily available and affordable.

Macular edema after cataract surgery in diabetic eyes evaluated by optical coherence tomography

AIM：To assess quantitative changes of the macula in diabetic eyes after cataract surgery using optical coherence tomography（OCT）and to estimate the incidence of development or worsening of macular edema（ME）in diabetic eyes with or without pre-existing ME.·METHODS：In this prospective,observational study,92eyes of 60 diabetic patients who underwent cataract surgery were evaluated before surgery and 1,3mo after surgery using OCT.Macular thickness was measured with OCT at nine macular subfields defined by the 9zones early treatment of diabetic retinopathy study（ETDRS）,as well as total macular volume obtained by OCT at 1,3mo after surgery were compared with baseline features obtained before surgery.In addition,the incidence of development or worsening of ME was analyzed in diabetic eyes with or without pre-existing ME.·R ESULTS：The central subfield mean thickness increased 21.0μm and 25.5μm at 1,3mo follow-up,respectively（〈0.01）.The average thickness of inner ring and outer ring increased 14.2μm and 9.5μm at 1mo,18.2μm and 12.9μm at 3mo.Central-involved ME developed in 12 eyes at 3mo,including 4 eyes with preexisting central-involved and 8 eyes with pre-existing non-central involved ME.Pre-existing diabetic macular edema（DME）was significantly associated with centralinvolved ME development（〈0.001）.·C ONCLUSION：A statistically significant increase could be detected in the central subfield as well as perifoveal and parafoveal sectors though the increase was mild.And eyes with pre-operative DME prior to cataract surgery are at higher risk for developing central-involved ME.

Evaluation of systemic risk factors in different optical coherence tomographic patterns of diabetic macular edema

AIM： To elucidate the relationship between systemic risk factors and different patterns of diabetic macular edema（DME） determined with optical coherence tomography（OCT）. METHODS： In this cross-sectional study, DME was classified by OCT as diffuse retinal thickness（DRT）, cystoid macular edema（CME） and serous retinal detachment（SRD） and the relationship between the systemic risk factors and DME patterns was evaluated. RESULTS： Of the 57 patients with DME, 21（36.8%） had DRT, 24（42.1%） had CME and 12（21.0%） had SRD. Microor macro-albuminuria was significantly higher in the DRT pattern（61.9%） compared with the SRD（50.0%） and CME patterns（25.0%; P=0.040）. Hemoglobin A1 c（Hb A1 c） level was significantly higher and patients were younger in the DRT pattern group（P=0.034, P=0.032）. Best corrected visual acuity was the worst and central macular thickness was the thickest in the CME pattern group. CONCLUSION： Micro-or macro-albuminuria may be more frequent and Hb A1 c level may be higher in patients with DRT. These patients are also seen to be younger than patients with non-DRT.

Improvement of visual acuity based on optical coherence tomography patterns following intravitreal bevacizumab treatment in patients with diabetic macular edema

AIMTo report the visual outcome based on various patterns of optical coherence tomography (OCT) morphology in diabetic macular edema (DME), following treatment with anti-VEGF intravitreal bevacizumab (IVB) injection.

Aqueous angiopoietin-like levels correlate with optical coherence tomography angiography metrics in diabetic macular edema

AIM:To quantitatively detect aqueous levels of angiopoietin-like(ANGPTL)3,ANGPTL4,and ANGPTL6 and investigate their correlation with optical coherence tomography angiography(OCTA)findings in patients with diabetic macular edema(DME).METHODS:This cross-sectional study included 23 patients(27 eyes)with type 2 diabetes and 16 control subjects(20 eyes).All patients underwent OCTA imaging and ultra-wide field fundus photography.Diabetic patients were categorized into two groups according to the presence or absence of diabetic retinopathy(DME group,14 patients,16 eyes);and non-diabetic retinopathy(NDR)group,9 patients,11 eyes,respectively.Aqueous levels of ANGPTL3,ANGPTL4,and ANGPTL6 were assessed using suspension array technology,and foveal-centered 3×3 mm2 OCTA scans were automatically graded to determine the central,inner,and full vessel density(CVD,IVD,FVD);central,inner,and full perfusion density(CPD,IPD,FPD),foveal avascular zone(FAZ)area,FAZ perimeter,and FAZ circularity index(FAZ-CI)on superficial capillary plexuses.Additionally,central subfield thickness(CST),cube volume(CV),and cube average thickness(CAT)were measured in a model of macular cube 512×128.RESULTS:Aqueous ANGPTL3 levels were not significantly different among the three groups(P>0.05).ANGPTL4 levels were significantly higher in the DME group than the control and NDR groups(P<0.0001 and P<0.001),while ANGPTL6 levels were significantly higher in the DME group than the control group(P<0.05).In the whole cohort,the aqueous ANGPTL3 levels correlated negatively with the IVD,FVD,IPD,and FPD,and positively with the CV and CAT.The aqueous ANGPTL4 levels correlated negatively with the CVD,IVD,FVD,CPD,IPD,and FPD,and positively with the FAZ perimeter,CST,CV,and CAT.The aqueous ANGPTL6 levels correlated negatively with the IVD,FVD,IPD,FPD,FAZCI and positively with CST,CV,CAT.CONCLUSION:ANGPTL4 and ANGPTL6 may be associated with vascular leakage in DME and may represent good targets for DME therapy.In addition,OCTA metrics may be useful for evaluating macular ischemia in DME.

Correlation between optical coherence tomography, multifocal electroretinogram findings and visual acuity in diabetic macular edema

AIM:To analyze the correlation between macular morphology and function in eyes with diabetic macular edema(DME).METHODS:Fifty-five eyes with different visual acuity(VA)of 32 patients who suffered from DME were analyzed using multifocal electroretinography(mfERG)and optical coherence tomography(OCT).The parameters of mfERG including implicit times and response amplitude were compared to those of 50 normal eyes of 36 age-matched subjects.Correlation analysis was performed between VA,the parameters of mfERG including implicit times and response amplitude,and the central macular thickness(CMT).RESULTS:The amplitude of N1 and P1 were significantly decreased and their latency were significantly increased in five ring regions of the retina in patients with DME.There was statistically significant correlation between logMAR BCVA and P1 amplitude densities in rings 1-4(r=-0.306,-0.536,-0.470,-0.362;P=0.023,<0.01,<0.01,0.007 respectively),N1 amplitude in ring 2 and ring 3(r=-0.035,-0.286;P=0.019,0.034 respectively).There was poor correlation between the CMT and best-corrected visual acuity(BCVA;r=0.288,P=0.033),but there was no significant correlation between CMT and amplitude or implicit time of N1 and P1(P>0.05)in the central macular ring.Multiple stepwise regression analysis showed that P1 amplitude density in ring 2 was the only contributor to the VA.CONCLUSION:It seems to be more appropriate of combining use of mfERG with OCT for the evaluation of macular function in eyes with DME.

Foveal avascular zone area and parafoveal vessel density measurements in different stages of diabetic retinopathy by optical coherence tomography angiography

AIM：To investigate foveal avascular zone（FAZ）and parafoveal vessel densities（PRVD）by means of optical coherence tomography angiography（OCTA）in diabetic patients with or without diabetic retinopathy（DR）and to assess the reproducibility of FAZ and PRVD measurements.METHODS：Sixty diabetic patients（60 eyes）with different stage of DR（graded according to the International Clinical Severity Scale for DR）and 20 healthy subjects underwent FAZ area and PRVD measurements using OCTA by two experienced examiners.FAZ area in all patients was also assessed using fluorescein angiography（FA）.RESULTS：In subject with proliferative DR and with moderate-severe non proliferative DR,FAZ area was significantly increased compared to healthy controls（P=0.025 and P=0.050 respectively measured with OCTA and P=0.025 and P=0.048 respectively measured with FA）.OCTA showed significantly less inter-observer variability compared to FA.Concordance correlation coefficient（CCC）for FAZ area measurements was 0.829（95%CI：0.736-0.891）P〈0.001 with FA and 1.000（95%CI：0.999-1.000）P〈0.001with OCTA.CCC was 0.834（95%CI：0.746-0.893）P〈0.001and 0.890（95%CI：0.828-0.930）P〈0.001 for parafoveal superficial and deep vessel density measurements,respectively.CONCLUSION：OCTA shows progressive increase of FAZ area and reduction of PRVD in both superficial and deep plexus at increasing DR severity.FAZ area and PRVD measurements using OCTA are highly reproducible.

Bimodal imaging of proliferative diabetic retinopathy vascular features using swept source optical coherence tomography angiography

AIM： To categorize neovessels morphology and to detect response to anti-angiogenic therapy by using structural and angiographic modes of swept source optical coherence tomography（SS-OCT）.METHODS： Thirty-two eyes with neovessels at disc（NVD） and neovessels elsewhere（NVE）-as diagnosed by fluorescein angiography-were included. Cross sectional OCT images of disc and macular regions were registered to enface OCT angiography（OCTA）, B-scan blood flow over lay and density maps. Three eyes received antiangiogenic treatment.RESULTS： Pin point registration of cross-sectional OCT and OCTA images differentiated active NVD with vascular elements from fibrous or equivalent fibrovascular elements. En face images delineated NVE as vascular tufts or area of filling while cross-sectional images differentiated NVE from microvascular intraretinal abnormality（IRMA）. All cases were associated with enlargement of foveal avascular zone and or areas of capillary non perfusion. Regressed NVD appeared as ghost vessel or pruned vascular loops after injection.CONCLUSION： Structural and angiographic modes of SS-OCT can detect, characterize and categorize the pattern of wide spectrum of neovessels based on blood flow data and density maps. It is potentially useful to detect ischemic changes in the vascular bed and regression of NVD after therapeutic regimens providing substitute for invasive techniques.

Retinal ganglion cell complex changes using spectral domain optical coherence tomography in diabetic patients without retinopathy

AIM：To assess the ganglion cell complex（GCC）thickness in diabetic eyes without retinopathy. METHODS：Two groups included 45 diabetic eyes without retinopathy and 21 non diabetic eyes. All subjects underwent full medical and ophthalmological history,full ophthalmological examination,measuring GCC thickness and central foveal thickness（CFT）using the RTVue~？ spectral domainoptical coherence tomography（SD-OCT）,and HbA1C level.RESULTS：GCC focal loss volume（FLV%）was significantly more in diabetic eyes（22.2% below normal）than normal eyes（P=0.024）. No statistically significant difference was found between the diabetic group and the control group regarding GCC global loss volume（GLV%）（P=0.160）. CFT was positively correlated to the average,superior and inferior GCC（P=0.001,0.000 and 0.001 respectively）and negatively correlated to GLV% and FLV%（P=0.002 and0.031 respectively）in diabetic eyes. C/D ratio in diabetic eyes was negatively correlated to average,superior and inferior GCC（P=0.015,0.007 and 0.017 respectively）. The FLV% was negatively correlated to the refraction and level of Hb A1c（P=0.019 and 0.013 respectively）and positively correlated to the best corrected visual acuity（BCVA）in log MAR in diabetic group（P=0.004）.CONCLUSION：Significant GCC thinning in diabetes predates retinal vasculopathy,which is mainly focal rather than diffuse. It has no preference to either the superior or inferior halves of the macula. Increase of myopic error is significantly accompanied with increased focal GCC loss. GCC loss is accompanied with increased C/D ratio in diabetic eyes.

Detection of diabetic retinopathy in its early stages using textural features of optical coherence tomography angiography

The aim of this study is to detect whether the quantitative textural features of optical coherencetomography angiography (OCTA) images can be used to detect the eyes in the early stage ofdiabetic retinopathy (DR) from eyes with diabetes and no DR (NDR). Textural features includingfractal dimension, contrast, correlation, entropy, energy, and homogeneity were calculatedfrom the OCTA images. The Student's t-test was performed to identify the textural featuresthat can be able to detect DR in the early stage. The area under the receiver operating characteristic(AUROC) curves, sensitivity, and specicity were calculated between the study groups.Our results indicated that the fractal dimension in ICP and SVP and the correlation in SVCshowed the statistical signicance between mild NPDR patients and NDR patients. The ROCanalysis results showed that the AUROC of the fractal dimension in ICP was 0.736 with 0.773sensitivity and 0.700 specicity. The cuto® point in ICP was 2.616. The OCTA-based fractaldimension was able to discriminate diabetic eyes with early retinopathy from healthy and NDRwith higher sensitivity and specicity. The OCTA-based correlation showed the power to differentiatethe mild NPDR eyes from the normal healthy and diabetic eyes. These results suggestthat texture-based features of OCTA have the potential to assist in the assessment of therapeuticinterventions to prevent early DR in diabetic subjects.

Retinal neurodegeneration in metabolic syndrome:a spectral optical coherence tomography study

AIM:To evaluate the effects of metabolic syndrome(Met S)on retinal neurodegeneration by optical coherence tomography(OCT).METHODS:Patients diagnosed as Met S were compared with the age and sex-matched healthy control group(CG).Waist circumference measurements,fasting serological biochemical tests,and systemic blood pressures of all participants were evaluated.The Met S group was divided into 3 subgroups according to the number of Met S components:hypertension,diabetes mellitus,dyslipidemia(low-,high-density lipoprotein,hypertriglyceridemia),and visceral obesity findings;3-component Met S3,4-component Met S4,and all-component Met S5.All patients underwent complete eye examination and spectral OCT retinal imaging.RESULTS:Totally 58 eyes of 58 patients were included in the Met S group and 63 eyes of 63 age and sex-matched healthy subjects were included in CG.Met S group was composed of 22 subjects in Met S3,21 subjects in Met S4,and 15 subjects in the Met S5 subgroup.Mean foveal thickness(Met S,218.7±23.1μm vs CG,228.8±21.9μm,P=0.015),mean inferior(Met S,283.4±17.0μm vs CG,288.7±38.4μm,P=0.002),superior(Met S,287.0±18.5μm vs CG 297.3±17.1μm,P=0.001),nasal(Met S 287.3±16.7μm vs CG 297.9±13.9μm,P=0.000)and temporal(274.5±17.6μm vs CG 285.6±13.6μm,P=0.000)thickness in the 3 mm Early Treatment of Diabetic Retinopathy Study(ETDRS)circle was significantly lower in the Met S group.There was no statistically significant difference in the mean inferior,superior,nasal,and temporal thickness of 6 mm ETDRS circle,total macular volume,peripapillary and macular retinal nerve fiber layer,macular ganglion cell layer with inner plexiform layer,and ganglion cell complex.No statistically significant difference was found in these values between the Met S3,Met S4,and the Met S5 groups.CONCLUSION:A significant reduction in central macular region thickness in Met S is detected and macular thickness is more susceptible to Met S induced neurodegeneration than peripapillary retinal nerve fiber layer.

Renal function and choroidal thickness using swept-source optical coherence tomography in diabetic patients

AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Demographic data included: age, sex, type and course of diabetes. Ocular data included: severity of diabetic retinopathy;retinal thickness at the central macular region, as well as choroidal thickness at the central and paracentral quadrants, using automatically generated maps by swept-source optical coherence tomography;presence of cystic macular edema;and ocular axial length(AXL). Lab-test parameters included: glycated hemoglobin(HbA1c), albuminuria, albumin/creatinine ratio in urine, and glomerular filtration rate. RESULTS: A significant negative correlation was mainly observed between several choroidal thicknesses, age(P<0.020) and ocular AXL(P<0.030). On the contrary, a significant positive correlation was found between all choroidal thicknesses, HbA1 c(P<0.035) and albuminuria(P<0.040). CONCLUSION: Choroidal thickness can represent an additional tool to help clinicians predicting the renal status in ocular treatment-na?ve diabetic patients.

Investigation of changes in thickness and reflectivity from layered retinal structures of healthy and diabetic eyes with optical coherence tomography

OCT is usually employed for the measurement of retinal thickness. However, coherent reflected light carries more information characterizing the optical properties of tissue. Therefore, optical property changes may provide further information regarding cellular layers and early damage in ocular diseases. We investigated the possibility of OCT in detecting changes in the optical backscattered signal from layered retinal structures. OCT images were obtained from diabetic patients without retinopathy (DM, n = 38 eyes) or mild diabetic retinopathy (MDR, n = 43 eyes) and normal healthy subjects (n = 74 eyes). The thickness and reflectivity of various layered structures were assessed using a custom-built algorithm. In addition, we evaluated the usefulness of quantifying the reflectivity of layered structures in the detection of retinal damage. Generalized estimating equations considering within-subject inter-eye relations were used to test for differences between the groups. A modified p value of <0.001 was considered statistically significant. Receiver operating characteristic (ROC) curves were constructed to describe the ability of each parameter to discriminate between the eyes of DM, MDR and healthy eyes. Thickness values of the GCL + IPL and OPL showed a significant decrease in the MDR eyes compared to controls. Significant decreases of total reflectance average values were observed in all layers in the MDR eyes compared with controls. The highest AUROC values estimated for the total reflectance were observed for the GCL+IPL, OPL and OS when comparing MDR eyes with controls. Total reflectance showed a better discriminating power between the MDR eyes and healthy eyes compared to thickness values. Our results suggest that the optical properties of the intraretinal layers may provide useful information to differentiate pathological from healthy eyes. Further research is warranted to determine how this approach may be used to improve diagnosis of early retinal neurodegeneration.

Quantitative analysis of early diabetic retinopathy based on optical coherence tomography angiography biological image

BACKGROUND With the development of the economy and improvements in living standards,the incidences of diabetes mellitus(DM)and diabetic retinopathy(DR),which is a complication of DM,are on the rise.AIM To analyze early DR in patients with macular zone changes in biological images using optical coherence tomography angiography METHODS A prospective case study was performed on 59 participants:35 healthy eyes(control group),35 eyes with diabetes but no DR group(no DR group),and 35 eyes with mild DR(NPDR group).All quantitative comparisons of parameters,including the fovea vascularity area,circularity index,and vascular complexity parameters,were performed using a biological image analysis software.RESULTS The foveal avascular zone(FAZ)area,FAZ circularity index,number of branches in the area,and the total of the single branches’length in the area was 0.366±0.031,0.834±0.037,3241.8±268.3,and 3.860×107±0.194×107,and 0.421±0.030,0.739±0.023,2956.6±476.4,and 3.177×107±0.161×107 in the no DR group and the NPDR group,respectively,which were significantly different from the corresponding parameters of the control group(P<0.05).Moreover,there were significant differences between these two groups(P<0.05).CONCLUSION This study shows that early microcirculation changes in the macular area of the retina is associated with disease progression.Early changes in DR can be analyzed using optical coherence tomography angiography.

The applications of optical coherence tomography angiography in diabetic retinopathy

Optical coherence tomography angiography(OCTA),an extent function of traditional optical coherence tomography(OCT),is a non-invasive,high-resolution imaging system designed to display vascular networks.The fundamental principle of OCTA is to achieve the signal of blood flow based on the analysis of complex OCT signal,amplitude of OCT signal or phase of OCT signal.OCTA can display and monitor the vascular abnormalities in patients with diabetic retinopathy(DR),including microaneurysms,vessel density(VD),nonperfusion,neovascularization,and other lesions.OCTA offers a new and potential horizon in the monitor of the DR progress and evaluation of DR treatment.

Intravitreal injection of conbercept for diabetic macular edema complicated with diabetic nephropathy

AIM:To observe the therapeutic effect of conbercept on diabetic macular edema(DME)complicated with diabetic nephropathy(DN).METHODS:In this retrospective study,54 patients(54 eyes)that diagnosed as DME from January 2017 to October 2021 were collected.The patients were divided into two groups:DME patients with DN(25 eyes),and DME patients without DN(29 eyes).General conditions were collected before treatment,laboratory tests include fasting blood glucose,HbA1c,microalbumin/creatinine,serum creatinine.Optical coherence tomography(OCT)was used to check the ellipsoidal zone(EZ)and external limiting membrane(ELM)integrity.Central macular thickness(CMT),best corrected visual acuity(BCVA),and retinal hyperreflective foci(HF)as well as numbers of injections were recorded.RESULTS:There were significant differences between fasting blood glucose,HbA1c,serum creatinine,urinary microalbumin/creatinine,and estimated glomerular filtration rate(eGFR)between the two groups(all P<0.05).EZ and ELM continuity in the DME+DN group was worse than that in the DME group(P<0.05).BCVA(logMAR)in the DME group was significantly better than that in the DME+DN group at the same time points during treatment(all P<0.05).CMT and HF values were significantly higher in the DME+DN group than that in the DME group at the all time points(all P<0.05)and significantly decreased in both groups with time during treatment.At 6mo after treatment,the mean number of injections in the DME+DN and DME group was 4.84±0.94 and 3.79±0.86,respectively.CONCLUSION:Conbercept has a significant effect in short-term treatment of DME patients with or without DN,and can significantly ameliorate BCVA,CMT and the number of HF,treatment efficacy of DME patients without DN is better than that of DME patients with DN.

Impact of COVID-19-related lifestyle changes on diabetic macular edema

AIM:To assess diabetic macular edema(DME)progression during the early phases of the COVID-19 pandemic,when severe societal restrictions raised the concern of possible deterioration of health in patients with systemic conditions,particularly those requiring frequent office visits.METHODS:This is a multicenter retrospective chart review of 370 patients(724 eyes)with an established diagnosis of DME seen on 3 separate visits between January 2019 and July 2021.Period 1 was January 2019 to February 2020(considered pre-COVID-19),period 2 was March 2020 to December 2020(considered the height of the pandemic;highest level of pandemic-related clinical and societal regulations)and period 3 was January 2021 to July 2021(re-adjustment to the new“pandemic norms”).Main outcome measures included visual acuity,body mass index(BMI),blood pressure(BP),hemoglobin A1c(HbA1c),macular thickness,patient adherence to scheduled ophthalmology visits,and DME treatment(s)received at each visit.To facilitate measurement of macular thickness,each macula was divided into 9 Early Treatment Diabetic Retinopathy Study(ETDRS)-defined macular sectors as measured by OCT imaging.RESULTS:There was no change of BMI,systolic BP,and diastolic BP between any of the time periods.HbA1c showed a very small increase from period 1(7.6%)to period 2(7.8%,P=0.015)and decreased back to 7.6%at period 3(P=0.12).Macular thickness decreased for 100%of macular regions.The central macular thickness decreased across all 3 periods from 329.5 to 316.6μm(P=0.0045).After analysis of multiple variables including HbA1c,BMI,adherence to scheduled appointments,different clinic centers,and treatment interventions,there was no easily identifiable subgroup of patients that experienced the increase in DME.CONCLUSION:DME doesn’t worsen during the COVID-19 pandemic,instead sustaining a very small but statistically significant improvement.While identifying a mechanism behind our findings is beyond the scope of this study,potential explanations may include a delay in retinal changes beyond our study period,an unexpected increase in treatment frequency despite pandemic restrictions,and an unanticipated pandemic-related improvement in some lifestyle factors that may have had a positive impact on DME.