Automatic diagnosis of diabetic retinopathy using vision transformer based on wide-field optical coherence tomography angiography

Diabetic retinopathy(DR)is one of the major causes of visual impairment in adults with diabetes.Optical coherence tomography angiography(OCTA)is nowadays widely used as the golden criterion for diagnosing DR.Recently,wide-field OCTA(WF-OCTA)provided more abundant information including that of the peripheral retinal degenerative changes and it can contribute in accurately diagnosing DR.The need for an automatic DR diagnostic system based on WF-OCTA pictures attracts more and more attention due to the large diabetic population and the prevalence of retinopathy cases.In this study,automatic diagnosis of DR using vision transformer was performed using WF-OCTA images(12 mm×12 mm single-scan)centered on the fovea as the dataset.WF-OCTA images were automatically classified into four classes:No DR,mild nonproliferative diabetic retinopathy(NPDR),moderate to severe NPDR,and proliferative diabetic retinopathy(PDR).The proposed method for detecting DR on the test set achieves accuracy of 99.55%,sensitivity of 99.49%,and specificity of 99.57%.The accuracy of the method for DR staging reaches up to 99.20%,which has been proven to be higher than that attained by classical convolutional neural network models.Results show that the automatic diagnosis of DR based on vision transformer and WF-OCTA pictures is more effective for detecting and staging DR.

Unified deep learning model for predicting fundus fluorescein angiography image from fundus structure image

The prediction of fundus fluorescein angiography(FFA)images from fundus structural images is a cutting-edge research topic in ophthalmological image processing.Prediction comprises estimating FFA from fundus camera imaging,single-phase FFA from scanning laser ophthalmoscopy(SLO),and three-phase FFA also from SLO.Although many deep learning models are available,a single model can only perform one or two of these prediction tasks.To accomplish three prediction tasks using a unified method,we propose a unified deep learning model for predicting FFA images from fundus structure images using a supervised generative adversarial network.The three prediction tasks are processed as follows:data preparation,network training under FFA supervision,and FFA image prediction from fundus structure images on a test set.By comparing the FFA images predicted by our model,pix2pix,and CycleGAN,we demonstrate the remarkable progress achieved by our proposal.The high performance of our model is validated in terms of the peak signal-to-noise ratio,structural similarity index,and mean squared error.

Predictive visual field outcomes after optic chiasm decompressive surgery by retinal vessels parameters using optical coherence tomography angiography

AIM:To evaluate the predictive value of superficial retinal capillary plexus(SRCP)and radial peripapillary capillary(RPC)for visual field recovery after optic cross decompression and compare them with peripapillary nerve fiber layer(pRNFL)and ganglion cell complex(GCC).METHODS:This prospective longitudinal observational study included patients with chiasmal compression due to sellar region mass scheduled for decompressive surgery.Generalized estimating equations were used to compare retinal vessel density and retinal layer thickness preand post-operatively and with healthy controls.Logistic regression models were used to assess the relationship between preoperative GCC,pRNFL,SRCP,and RPC parameters and visual field recovery after surgery.RESULTS:The study included 43 eyes of 24 patients and 48 eyes of 24 healthy controls.Preoperative RPC and SRCP vessel density and pRNFL and GCC thickness were lower than healthy controls and higher than postoperative values.The best predictive GCC and pRNFL models were based on the superior GCC[area under the curve(AUC)=0.866]and the tempo-inferior pRNFL(AUC=0.824),and the best predictive SRCP and RPC models were based on the nasal SRCP(AUC=0.718)and tempo-inferior RPC(AUC=0.825).There was no statistical difference in the predictive value of the superior GCC,tempo-inferior pRNFL,and tempo-inferior RPC(all P>0.05).CONCLUSION:Compression of the optic chiasm by tumors in the saddle area can reduce retinal thickness and blood perfusion.This reduction persists despite the recovery of the visual field after decompression surgery.GCC,pRNFL,and RPC can be used as sensitive predictors of visual field recovery after decompression surgery.

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.

Automated evaluation of parapapillary choroidal microvasculature in crowded optic discs:a controlled,optical coherence tomography angiography study

AIM:To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography(OCT-A).METHODS:Thirty patients with crowded discs,and 47 control subjects were enrolled in the study.One eye of each individual was included and OCT-A scans of optic discs were obtained in a 4.5×4.5 mm^(2) rectangular area.Radial peripapillary capillary(RPC)density,peripapillary retinal nerve fiber layer(pRNFL)thickness,cup volume,rim area,disc area,cup-to-disc(c/d)area ratio,and vertical c/d ratio were obtained automatically using device software.Automated parapapillary choroidal microvasculature(PPCMv)density was calculated using MATLAB software.When the vertical c/d ratio of the optic disc was absent or small cup,it was considered as a crowded disc.RESULTS:The mean signal strength index of OCT-A images was similar between the crowded discs and control eyes(P=0.740).There was no difference in pRNFL between the two groups(P=0.102).There were no differences in RPC density in whole image(P=0.826)and peripapillary region(P=0.923),but inside disc RPC density was higher in crowded optic discs(P=0.003).The PPCMv density in the inner-hemisuperior region was also lower in crowded discs(P=0.026).The pRNFL thickness was positively correlated with peripapillary RPC density(r=0.498,P<0.001).The inside disc RPC density was negatively correlated with c/d area ratio(r=-0.341,P=0.002).CONCLUSION:The higher inside disc RPC density and lower inner-hemisuperior PPCMv density are found in eyes with crowded optic discs.

Retinal capillary plexus in Parkinson’s disease using optical coherence tomography angiography

AIM:To evaluate the alterations of the retinal microvasculature and foveal avascular zone in patients with Parkinson’s disease(PD)using optical coherence tomography angiography(OCT-A).METHODS:A retrospective study of PD patients examined in the Ophthalmology Department of the General Hospital of Athens,“Georgios Gennimatas”from March 2021 to March 2022 was conducted.Totally 44 patients with PD were included and 18 healthy controls were examined,hence a total of 124 eyes were enrolled in the study.The foveal and parafoveal superficial and deep capillary plexus vascular density(fSCP-VD,fDCP-VD,pSCP-VD,pDCP-CD)and foveal avascular zone(FAZ)were quantified with OCTA.Optical coherence tomography(OCT)was used to measure macular thickness.Our statistical analysis was conducted by using a mixed effect linear regression model.RESULTS:After adjustment for age and gender,the mean parafoveal superficial capillary plexus vascular density(pSCP-VD)and mean parafoveal deep capillary plexus vascular density(pDCP-VD)were significantly decreased in individuals with PD(P<0.001 in both)by-2.35(95%CI-3.3,-1.45)and-7.5(95%CI-10.4,-4.6)respectively.fSCP-VD and fDCP-VD didn’t approach statistical significance.The FAZ area and perimeter were significantly decreased(P<0.001 in both)by-0.1 mm^(2)(95%CI-0.13,-0.07)and-0.49 mm^(2)(95%CI-0.66,-0.32)respectively.Circularity didn’t approach statistical significance.Central retinal thickness(CRT)was significantly decreased in individuals with PD(P<0.001)by-23.1μm(95%CI-30.2,-16)and temporal retinal thickness(TRT)was decreased(P=0.025)by-11μm(95%CI-22,-1.5)while nasal retinal thickness(NRT)only approached statistical significance(P=0.066).CONCLUSION:The mean pSCP-VD,pDCP-VD,CRT and TRT are significantly decreased and FAZ is altered in individuals with PD.These findings can be potentially used as biomarkers for the diagnosis and evaluation of early PD.

Left atrial appendage occluder detachment treated with transthoracic ultrasound combined with digital subtraction angiography guided catcher:A case report

BACKGROUND There are very few cases of cardiac occluder detachment,and it is rare to completely remove the occluder using interventional methods without undergoing thoracotomy surgery after detachment.This case innovatively used ultrasound guidance combined with digital subtraction angiography(DSA)to completely remove the occluder,accumulating some experience.CASE SUMMARY The patient underwent left atrial appendage occlusion surgery in our hospital due to atrial fibrillation.After the surgery,the occluder fell off and became free in the left ventricle,which is very dangerous.We innovatively used ultrasound guidance,combined with DSA,and interventional surgery to successfully capture the free occluder using a catcher,completely remove it,and then re implant a new left atrial appendage occluder.After the surgery,the patient recovered very well.CONCLUSION The size selection of the occluder is slightly conservative,and the shape of the left atrial appendage opening is irregular.

Epidemiological, Clinical and Coronary Angiography Aspects of Acute Coronary Syndrome in the Cardiology Department of the Hospital Mother-Child “Le Luxembourg”Mali

Introduction: Cardiac catheterisation plays a fundamental role in the management of acute coronary syndrome. These explorations require heavy, complex and costly equipment and a large team of doctors, nurses and technicians with highly specialized training. Aims: To describe epidemiological, clinical and coronary angiography aspects of patients with acute coronary syndrome. Patients and Methods: Descriptive study from September 2019 to December 2023 in the Cardiology Department of the Hôpital Mère-Enfant of Bamako. Inclusion criteria were patients admitted for coronary angiography with the diagnosis of acute coronary syndrome. Results: During the study period, 1253 patients underwent coronary angiography, 596 of whom had acute coronary syndrome as an indication, representing a hospital frequency of 47%. Sex-ratio was 2.10. Mean age of patients was 58.5 ± 11.39 years. ST elevation acute coronary syndrome was the most common indication with 63.92% of cases. High blood pressure was the main cardiovascular risk factor with 58.7% of cases, and radial access approach was used in 98% of cases. Coronary angiography was pathological in 91.70% of cases (n = 548). Patients with lesions of anterior interventricular artery were 73.73% of cases. Tritruncal lesions accounted for 40.63% of cases. Conclusion: ST elevation acute coronary syndrome is the most frequent manifestation of acute coronary syndrome. Anterior interventricular artery is most often the culprit lesion for our patients.

Coronary Artery Patterns in Diabetic Patients Undergoing Diagnostic Coronary Angiography-Data from a Major Cardiac Center in Yemen

Background: Diabetes mellitus (DM) is independently associated with an increased risk of cardiovascular mortality and morbidity, including coronary artery disease (CAD). CAD is a shared burden disease and the leading cause of death in developed and developing countries. We aimed to assess the angiographic patterns of coronary arteries in patients with DM in a developing country (Yemen) as the first study. Methods: This study is a cross-sectional, prospective, observational study that includes a total of 250 patients who were admitted for elective diagnostic coronary angiography. Results: 96 (38.4%) patients were diabetics;68% were male;mean age was 57 ± 11 years. The incidence of three-vessel disease was 31.2% of patients. Considering the severity of lumen occlusion, (11.2%) of patients had non-significant lesions, (37.6%) of patients had significant lesions, and (32%) had total occlusive lesions. Lesions were of LAD in 76%, RCA in 60%, and LCX in 52% of the population. Among diabetics, two and 3-vessel diseases (33.3% vs. 20.8% & 50% vs. 19.5%, P = 0.001), left main lesion (10.4% vs. 2.6%, P = 0.012), significant stenosis (41.7% vs. 35.1%, P = 0.032), total occlusion of coronary arteries (43.8% vs. 19.5%, P = 0.032) and type C lesion (66.7% vs. 35.1%, P = 0.010) were more frequent than non-DM patients. Conclusion: The burden of significant and severe coronary lesions is more common among DM, which may be the major cause of morbidity and mortality of DM in developing countries.

Effects of Continuous Precision Nursing Model on Knowledge, Attitudes, and Practices (KAP) Behavior and Cardiac Function in Patients after Percutaneous Coronary Angiography and Stent Implantation

Objective:To explore the impact of a continuous precision nursing model on patients’Knowledge,Attitudes,and Practices(KAP)and cardiac function during the nursing process of patients undergoing percutaneous coronary angiography and stent implantation.Methods:Ninety patients who underwent percutaneous coronary angiography and stent implantation in our hospital from April 2022 to April 2023 were selected and randomly divided into the control group(45 cases),in which routine nursing support was carried out during the treatment process,and the observation group(45 cases),in which continuous precision nursing model was carried out during the treatment process.Comparisons were made between the two groups of patients on their KAP,cardiac function,and quality of life during recovery.Results:There was no difference in the left ventricular ejection fraction(LVEF),cardiac output(CO),and cardiac index(CI)levels before intervention.After the intervention,the levels of cardiac function in the observation group were higher than those of the control group(P<0.05).There was no difference in the Exercise of Self-Care Agency(ESCA)self-care ability scale scores before the intervention.After the intervention,the observation group had higher ESCA scores than the control group(P<0.05).Conclusion:Implementation of a continuous precision nursing model in the care of patients undergoing percutaneous coronary angiography and stent implantation improved the patient’s cardiac function,and KAP,and promoted recovery.

In vivo quantification of human aqueous veins by enhanced depth imaging optical coherence tomography and optical coherence tomography angiography images

AIM:To investigate the aqueous vein in vivo by using enhanced depth imaging optical coherence tomography(EDI-OCT)and optical coherence tomography angiography(OCTA).METHODS:In this cross-sectional comparative study,30 healthy participants were enrolled.Images of the aqueous and conjunctival veins were captured by EDI-OCT and OCTA before and after water loading.The area,height,width,location depth and blood flow of the aqueous vein and conjunctival vein were measured by Image J software.RESULTS:In the static state,the area of the aqueous vein was 8166.7±3272.7μm^(2),which was smaller than that of the conjunctival vein(13690±7457μm^(2),P<0.001).The mean blood flow density of the aqueous vein was 35.3%±12.6%,which was significantly less than that of the conjunctival vein(51.5%±10.6%,P<0.001).After water loading,the area of the aqueous vein decreased significantly from 8725.8±779.4μm^(2)(baseline)to 7005.2±566.2μm^(2)at 45min but rose to 7863.0±703.2μm^(2)at 60min(P=0.032).The blood flow density of the aqueous vein decreased significantly from 41.2%±4.5%(baseline)to 35.4%±3.2%at 30min but returned to 45.6%±3.6%at 60min(P=0.021).CONCLUSION:The structure and blood flow density of the aqueous vein can be effectively evaluated by OCT and OCTA.These may become biological indicators to evaluate aqueous vein changes and aqueous outflow resistance under different interventions in glaucoma patients.

Clinical anatomy of hepatic vessels by computed tomography angiography:A minireview

The liver has a complex vascular anatomy with a unique dual blood supply.Clinical conditions of the liver vary widely and include disorders originating in the vascular and biliary systems as well as the parenchyma.In most vascular disorders,the effects on the liver are generally subclinical because of its abundant blood supply.However,early diagnosis of such vascular diseases can significantly reduce patient morbidity and mortality.Because imaging findings of vascular disease are not always readily apparent,diagnosis can be difficult.Computed tomography angiography is an excellent imaging modality for visualizing the vascular anatomy of patients for treatment planning.In this review article,we focus on the vascular anatomy of the liver and the imaging findings in some acute hepatic vascular diseases.

Novel fast FFR derived from coronary CT angiography based on static first-pass algorithm:a comparison study

BACKGROUND Fractional flow reserve(FFR)is the invasive gold standard for evaluating coronary arterial stenosis.However,there have been a few non-invasive methods such as computational fluid dynamics FFR(CFD-FFR)with coronary CT angiography(CCTA)images that can perform FFR assessment.This study aims to develop a new method based on the principle of static first-pass of CT perfusion imaging technique(SF-FFR)and evaluate the efficacy in direct comparisons between CFD-FFR and the invasive FFR.METHODS A total of 91 patients(105 coronary artery vessels)who were admitted from January 2015 to March 2019 were enrolled in this study,retrospectively.All patients underwent CCTA and invasive FFR.64 patients(75 coronary artery vessels)were successfully analyzed.The correlation and diagnostic performance of SF-FFR method on per-vessel basis were analyzed,using invasive FFR as the gold standard.As a comparison,we also evaluated the correlation and diagnostic performance of CFD-FFR.RESULTS The SF-FFR showed a good Pearson correlation(r=0.70,P<0.001)and intra-class correlation(r=0.67,P<0.001)with the gold standard.The Bland-Altman analysis showed that the average difference between the SF-FFR and invasive FFR was 0.03(0.11–0.16);between CFD-FFR and invasive FFR was 0.04(-0.10–0.19).Diagnostic accuracy and area under the ROC curve on a per-vessel level were 0.89,0.94 for SF-FFR,and 0.87,0.89 for CFD-FFR,respectively.The SF-FFR calculation time was about 2.5 s per case while CFD calculation was about 2 min on an Nvidia Tesla V100 graphic card.CONCLUSIONS The SF-FFR method is feasible and shows high correlation compared to the gold standard.This method could simplify the calculation procedure and save time compared to the CFD method.

Triglyceride glucose index predicts in-hospital mortality in patients with ST-segment elevation myocardial infarction who underwent primary angiography

OBJECTIVES To assess the correlation between triglyceride glucose(TyG)index and in-hospital mortality in patients with ST-segment elevation myocardial infarction(STEMI).METHODS A total of 2190 patients with STEMI who underwent primary angiography within 12 h from symptom onset were selected from the prospective,nationwide,multicenter CAMI registry.TyG index was calculated with the formula:Ln[fasting triglycerides(mmol/L)×fasting glucose(mmol/L)/2].Patients were divided into three groups according to the tertiles of TyG index.The primary endpoint was in-hospital mortality.RESULTS Overall,46 patients died during hospitalization,in-hospital mortality was 1.5%,2.2%,2.6%for tertile 1,tertile 2,and tertile 3,respectively.However,TyG index was not significantly correlated with in-hospital mortality in single-variable logistic regression analysis.Nonetheless,after adjusting for age and sex,TyG index was significantly associated with higher mortality when regarded as a continuous variable(adjusted OR=1.75,95%CI:1.16-2.63)or categorical variable(tertile 3 vs.tertile 1:adjus-ted OR=2.50,95%CI:1.14-5.49).Furthermore,TyG index,either as a continuous variable(adjusted OR=2.54,95%CI:1.42-4.54)or categorical variable(tertile 3 vs.tertile 1:adjusted OR=3.57,95%CI:1.24-10.29),was an independent predictor of in-hospital mortality after adjusting for multiple confounders in multivariable logistic regression analysis.In subgroup analysis,the pro-gnostic effect of high TyG index was more significant in patients with body mass index<18.5 kg/m2(P interaction=0.006).CONCLUSIONS This study showed that TyG index was positively correlated with in-hospital mortality in STEMI patients who underwent primary angiography,especially in underweight patients.

Evaluation of optic nerve head vessels density changes after phacoemulsification cataract surgery using optical coherence tomography angiography

·AIM:To evaluate optic nerve head(ONH)vessel density(VD)changes after cataract surgery using optical coherence tomography angiography(OCTA).·METHODS:This was a prospective observational study.Thirty-four eyes with mild/moderate cataracts were included.ONH scans were obtained before and 3mo after cataract surgery using OCTA.Radial peripapillary capillary(RPC)density,all VD,large VD and retinal nerve fiber layer thickness(RNFLT)in total disc,inside disc,and different peripapillary sectors were assessed and analyzed.Image quality score(QS),fundus photography grading and bestcorrected visual acuity(BCVA)were also collected,and correlation analyses were performed between VD change and these parameters.·RESULTS:Compared with baseline,both RPC and all VD increased in inside disc area 3mo postoperatively(from 47.5%±5.3%to 50.2%±3.7%,and from 57.87%±4.30%to 60.47%±3.10%,all P<0.001),but no differences were observed in peripapillary area.However,large VD increased from 5.63%±0.77%to 6.47%±0.72%in peripapillary ONH region(P<0.001).RPC decreased in inferior and superior peripapillary ONH parts(P=0.019,<0.001 respectively).There were obvious negative correlations between RPC change and large VD change in inside disc,superior-hemi,and inferior-hemi(r=-0.419,-0.370,and-0.439,P=0.017,0.044,and 0.015,respectively).No correlations were found between VD change and other parameters including QS change,fundus photography grading,postoperative BCVA,and postoperative peripapillary RNFLT.·CONCLUSION:RPC density and all VD in the inside disc ONH region increase 3mo after surgery in patients with mild to moderate cataract.No obvious VD changes are found in peripapillary area postoperatively.

Changes of retinal vessel density in low to moderate myopic eyes with orthokeratology evaluated by optical coherence tomography angiography

AIM:To explore the effect of orthokeratology(OK)fitting on retinal vessel density in low to moderate myopia adolescents by using optical coherence tomography angiography.METHODS:Children aged 10 to 14y with a cycloplegic spherical equivalent refraction of−0.50 diopter(D)to−5.00 D and astigmatism with more than−1.50 D were recruited.The enrolled adolescents were divided into OK group and spectacle group.During regular followup,adolescents were measured respectively at pre-wear,1,3,and 6mo after treatment.The follow-up included uncorrected distance visual acuity(UDVA),axial length(AL),superficial capillary plexus density(SCPD),deep capillary plexus density(DCPD),central retinal thickness(CRT),foveal avascular zone area(FAZ-A),foveal avascular zone perimeter(FAZ-P)and foveal vessel density in a 300-μmwide region around foveal avascular zone(FD-300).The collected data were analyzed using statistical methods.RESULTS:By one month,SCPD significantly increased in the fovea and superior retina,and DCPD significantly increased inferiorly in OK group compared to spectacle group(P<0.05).By three months,there were significant increases in SCPD in the fovea and inferior retina,and DCPD in the parafovea,superior,and inferior retina in OK group(P<0.05),while the increase in SCPD and DCPD in the fovea were observed by six months(P<0.05).The FD-300 significantly increased at every follow-up in OK group compared to spectacle group(P<0.05).No significant differences in the CRT,FAZ-A and FAZ-P and FD-300 were observed between two groups(P>0.05).OK group showed a significant improvement in UDVA after wearing OK,compared to spectacle group(P<0.01),while the AL did not show a significant difference between two groups(P>0.05).CONCLUSION:Short-term OK worn can increase local retinal vessel density in adolescents with low-to-moderate myopia.

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.

Macular vascularisation changes analysed using OCT angiography after successful rhegmatogenous retinal detachment repair

AIM:To analyse the macular vascularisation changes analysed using optical coherence tomography angiography(OCTA)after successful rhegmatogenous retinal detachment(RRD)repair by comparing gas vs silicone oil and macula-on vs macula-off.METHODS:This retrospective data collection included 77 eyes with RRD that underwent pars plana vitrectomy(PPV)and gas or silicone oil tamponade.We performed an OCTA during the postoperative control between 6 and 24mo after the last surgery and evaluated the main parameters measured by OCTA:foveal avascular zone(FAZ)and parafoveolar vascular density(PVD)in the superficial capillary plexus.The patients were divided into four groups:RRD with macular involvement treated with gas tamponade,RRD without macular involvement treated with gas tamponade,RRD with macular involvement treated with silicone oil tamponade and RRD without macular involvement treated with silicone oil tamponade.A one-way ANOVA test combined with post hoc Bonferroni corrections compared FAZ sizes and PVD in all four groups.RESULTS:The FAZ size was statistically significantly larger in eyes with RRD involving the macula than in those not involving it(P=0.005).There was no statistically significant difference in the FAZ sizes of the eyes treated with silicone oil tamponade compared to those treated with gas tamponade(P=0.54).There was no statistically significant difference in the PVD comparing all four groups.CONCLUSION:Despite the known risks associated with silicone oil,our findings suggest that the type of tamponade used during PPV to treat an RRD has no significant effect on the future integrity of the PVD or the size of the FAZ in the superficial capillary plexus as measured by OCTA.

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 characteristics of exudative and non-exudative treatmentnaive pachychoroid neovasculopathy

AIM:To describe the optical coherence tomography angiography(OCTA)characteristics of exudative and nonexudative treatment-naïve pachychoroid neovasculopathy(PNV).METHODS:Thirty-five patients with exudative treatmentnaïve PNV and 13 with non-exudative treatment-naïve PNV between March 2020 and December 2021 were included.All patients underwent ophthalmologic examination,including fluorescein angiography(FA),indocyanine green angiography(ICGA),spectral-domain OCT,and OCTA.The clinical data of the patients were retrospectively analyzed.RESULTS:The study included 51 eyes from 46 patients,of whom 33(71.7%)were male.The central macular thickness(CMT)in the exudative PNV group was significantly higher than that in the non-exudative PNV group(383.97±132.16μm vs 213.13±51.63μm;P<0.001).The maximum height of flat irregular pigment epithelial detachments(FIPED)was 45.40±11.86μm in the non-exudative PNV group,significantly lower than the 71.58±20.91μm(P<0.001)in the exudative PNV group.The area of PNV of the non-exudative PNV group was,significantly larger than that of the exudative PNV group(1.06±0.84 mm2 vs 0.63±0.80 mm2,P=0.016).There was a significant difference in PNV morphology between the two groups(P<0.001).Multivariate logistic regression analysis found that the maximum height of FIPED(OR=1.156,95%CI:1.019-1.312;P=0.024)and microvascular branches(OR=69.412,95%CI:3.538-1361.844;P=0.005)were independent predictors of PNV activity.CONCLUSION:The OCTA imaging finds that there are significant differences in CMT,maximum height of FIPED,PNV area,and morphology of exudative PNV and non-exudative PNV groups.OCTA can accurately identify the clinical and imaging features of exudative and nonexudative treatment-naïve PNV,and distinguish PNV activity.