Automatic segmentation of foveal avascular zone based on adaptive watershed algorithm in retinal optical coherence tomography angiography images

The size and shape of the foveal avascular zone(FAZ)have a strong positive correlation with several vision-threatening ret inovascular diseases.The identification,segmentation and analysis of FAZ are of great significance to clinical diagnosis and treatment.We presented an adaptive watershed algorithm to automatically extract F AZ from retinal optical coherence tomography angiography(OCTA)images.For the traditional watershed algorithm,"over-segmentation"is the most common problem.FAZ is often incorrectly divided into multiple regions by redundant"dams".This paper analyzed the relationship between the"dams"length and the maximum inscribed circle radius of FAZ,and proposed an adaptive watershed algorithm to solve the problem of"over-segmentation".Here,132 healthy retinal images and 50 diabetic retinopathy(DR)images were used to verify the accuracy and stability of the algorithm.Three ophthal-mologists were invited to make quan titative and qualitative evaluations on the segmentation results of this algorithm.The quantitative evaluation results show that the correlation coffi-cients between the automatic and manual segmentation results are 0.945(in healthy subjects)and 0.927(in DR patients),respectively.For qualitative evaluation,the percentages of"perfect segmentation"(score of 3)and"good segmentation"(score of 2)are 99.4%(in healthy subjects)and 98.7%(in DR patients),respectively.This work promotes the application of watershed algorithm in FAZ segmentation,making it a useful tool for analyzing and diagnosing eye diseases.

Superficial foveal avascular zone area changes before and after idiopathic epiretinal membrane surgery

To investigate the foveal morphological changes and foveal avascular zone（FAZ）area before and after epiretinal membrane（ERM）surgery.Twenty-two eyes with treatmentnaive ERM were included in this retrospective study.The central foveal thickness（CFT）and FAZ area were measured via swept-source optical coherence tomography（SS-OCT）and OCT angiography pre-and postoperatively.The unaffected fellow eyes were used as controls.The preoperative superficial FAZ area was significantly smaller in patients（0.08±0.04 mm^2）than in controls（0.33±0.09 mm^2;P〈0.001）.The postoperative superficial FAZ（0.12±0.06 mm^2）area was significantly greater than the preoperative area（P〈0.001）.The preoperative superficial FAZ area was strongly negatively correlated with CFT（P〈0.001,rho=-0.763）.ERM induced significant foveal morphological changes and reduction of the superficial FAZ area.Foveal thickness was restored and FAZ area increased postoperatively.However,the process is rather slow and the recovery is incomplete.

Various configuration types of the foveal avascular zone with related factors in normal Chinese adults with or without myopia assessed by swept-source OCT angiography

·AIM:To describe the morphological characteristics of foveal avascular zone(FAZ)in normal Chinese adults with or without myopia by swept-source optical coherence tomography angiography(SS-OCTA)and analyze the possible associated factors.·METHODS:Normal Chinese adults with or without myopia aged between 18 and 60 y were recruited into the study.One eye in each individual was randomly selected for scanning using SS-OCTA.FAZ parameters,central retinal thickness(CRT)and central choroidal thickness(CCT)were then analyzed.Correlations between systemic and ocular variables and FAZ parameters were subsequently evaluated.The subgroup analysis based on refractive error was also carried out.·RESULTS:In total,127 eyes out of 127 normal subjects were finally included in the study(mean age29.5±8.22 y,61 males and 66 females).The pattern of FAZ was variable:round configuration in 28 eyes(22%),quadrilateral configuration in 23 eyes(18%),pentagonal configuration in 20 eyes(16%),oval configuration in 15 eyes(12%),triangular configuration in 6 eyes(5%)and irregular configuration in 35 eyes(28%).The mean area of FAZ was0.37±0.12 mm^(2).Females had a larger FAZ(0.41±0.11 mm^(2)vs0.32±0.11 mm^(2))compared with that of males(P<0.01).All myopic individuals showed smaller FAZ area and perimeter compared with that of normal individuals(P<0.01).There was no obvious correlation between age and FAZ.In the univariate regression analysis,both axial length(AL)and refractive error were significantly related to FAZ parameters.However,only CRT showed negative correlation with FAZ in the multivariate regression analysis.·CONCLUSION:The pattern of FAZ configuration in normal Chinese adults with or without myopia is highly variable.Establishing quantitative parameters of FAZ would not only provide details of macular pathophysiology but could possibly contribute as a biomarker in disease staging.

Automatic quantification of superficial foveal avascular zone in optical coherence tomography angiography implemented with deep learning

An accurate segmentation and quantification of the superficial foveal avascular zone(sFAZ)is important to facilitate the diagnosis and treatment of many retinal diseases,such as diabetic retinopathy and retinal vein occlusion.We proposed a method based on deep learning for the automatic segmentation and quantification of the sFAZ in optical coherence tomography angiography(OCTA)images with robustness to brightness and contrast(B/C)variations.A dataset of 405 OCTA images from 45 participants was acquired with Zeiss Cirrus HD-OCT 5000 and the ground truth(GT)was manually segmented subsequently.A deep learning network with an encoder–decoder architecture was created to classify each pixel into an sFAZ or non-sFAZ class.Subsequently,we applied largestconnected-region extraction and hole-filling to fine-tune the automatic segmentation results.A maximum mean dice similarity coefficient(DSC)of 0.976±0.011 was obtained when the automatic segmentation results were compared against the GT.The correlation coefficient between the area calculated from the automatic segmentation results and that calculated from the GT was 0.997.In all nine parameter groups with various brightness/contrast,all the DSCs of the proposed method were higher than 0.96.The proposed method achieved better performance in the sFAZ segmentation and quantification compared to two previously reported methods.In conclusion,we proposed and successfully verified an automatic sFAZ segmentation and quantification method based on deep learning with robustness to B/C variations.For clinical applications,this is an important progress in creating an automated segmentation and quantification applicable to clinical analysis.

Quantitative Assessment of Foveal Avascular Zone in Patients with Early and Intermediate Nonexudative Age-Related Macular Degeneration Using Optical Coherence Tomography-Angiography

Optical coherence tomography-angiography (OCT-A) is a relatively new non-invasive imaging technique which provides three-dimensional visualization of the retinal and choroidal microvasculature. Recently, OCT-A is widely used in the diagnosis of age-related macular degeneration (AMD). Purpose: To compare 3 quantitative indexes of foveal avascular zone (FAZ)—area (A), perimeter (Pm), and circularity (C) in patients with early and intermediate nonexudative AMD and healthy subjects using OCT-A. Methods: Eighty-nine patients with nonexudative AMD (n = 89 eyes) were enrolled in the study. They were compared with sex- and age-matched control group of 66 healthy subjects (n = 66 eyes). The patients with nonexudative AMD were divided into 2 subgroups—early AMD (n = 42 eyes) and intermediate AMD (n = 47 eyes). All participants underwent OCT-A (3 × 3 mm scans, Cirrus HD-OCT, Angioplex, Carl Zeiss Meditec, Dublin, CA). Results: There was no statistically significant difference in all 3 assessed indexes between the early AMD subgroup and the control group (A ? P = 0.139;Pm ? P = 0.230;and C ? P = 0.191). There was also no statistically significant difference in all 3 assessed indexes between the intermediate AMD subgroup and the control group (A ? P = 0.106, Pm ? P = 0.124, and C ? P = 0.102, respectively). Conclusions: According to our results from the assessment of FAZ in patients with early and intermediate AMD, we hypothesize that macular perfusion remains fairly unchanged in the nonexudative stages of the disease. OCT-A is a reliable technique for visualizing and quantifying FAZ in patients with nonexudative AMD.

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.

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.

基于OCTA测量黄斑中心凹无血管区形态在眼部疾病中的应用研究进展

黄斑中心凹无血管区(FAZ)是视网膜上视觉最敏锐的区域,由视网膜黄斑区毛细血管丛相互连接而成,其形态可以间接反映黄斑区微循环的变化。光学相干断层扫描血管成像(OCTA)技术可以无创的可视化和量化FAZ区域,且具有较好的重复性和可靠性,OCTA展现出的巨大价值使其成为眼科及各个领域重要的辅助检查工具。在高度近视、糖尿病视网膜病变、青光眼等眼科疾病中,FAZ的面积及周长已被证实具有临床诊断价值,近年来FAZ的几何形态也展现出一定的临床意义,圆度指数、非圆指数、轴比等描述FAZ几何形态的参数为疾病研究提供了新视角。全方面研究FAZ区域的形态特征有助于探索眼部疾病发生和发展机制,或可预测疾病的早期变化及精确病理分期,为监测疾病进展及评估患者的视觉预后提供理论依据。

视网膜静脉阻塞继发黄斑水肿抗VEGF治疗后OCTA指标变化与基线房水细胞因子的相关性分析

目的探讨视网膜静脉阻塞继发黄斑水肿(RVO-ME)患者抗血管内皮生长因子(VEGF)治疗后光学相干断层扫描血管成像(OCTA)指标变化与基线房水细胞因子的关系。方法纳入2021年10月至2023年1月在南京医科大学眼科医院确诊为RVO-ME的患者30例30眼,均采用3+PRN方案的玻璃体内注射抗VEGF药物。分别收集第1次和第3次注射前的房水,采用Luminex液相芯片技术测定VEGF、白细胞介素(IL)、γ-干扰素(IFN-γ)、细胞间黏附分子-1(ICAM-1)和血小板源性生长因子(PDGF)等细胞因子的表达水平。利用OCTA测量黄斑中心凹视网膜厚度(CMT)、黄斑中心凹无血管区(FAZ)面积、周长(PERIM)、非圆度指数(AI)、FAZ范围300μm宽度内的血管密度(FD-300)。采用国际标准对数视力表检查最佳矫正视力(BCVA),并换算为最小分辨角对数(logMAR)视力。比较RVO-ME患者抗VEGF治疗前后房水中细胞因子表达水平和OCTA指标的变化,分析治疗后OCTA指标变化与基线房水细胞因子的关系。结果RVO-ME患者患眼治疗后房水细胞因子中VEGF、ICAM-1、PDGF、IL-8、IL-10表达水平均下降,差异均有统计学意义(均为P<0.05);治疗后BCVA改善(P<0.001),CMT、AI及FD-300指标均下降,差异均有统计学意义(均为P<0.05)。相关性分析结果显示,基线IL-13水平与AI变化值呈负相关(r=-0.388,P<0.05);基线IL-8水平与FD-300变化值呈负相关(r=-0.421,P<0.05)。结论基线房水细胞因子IL-13和IL-8可能与RVO-ME患眼抗VEGF治疗后视网膜黄斑区微血管结构改善程度有关。针对RVO-ME的治疗与管理不应局限于抗血管治疗,还应针对性进行抗炎治疗。

OCTA评估黄斑中心凹无血管区参数对早期糖尿病视网膜病变的诊断价值

目的:分析光学相干断层扫描血管成像(OCTA)评估黄斑中心凹无血管区(FAZ)参数对早期糖尿病视网膜病变(DR)的诊断价值。方法:回顾性研究。选择2019-06/2022-12我院收治的2型糖尿病(T2DM)合并糖尿病视网膜病变(DR)患者209例209眼为DR组,根据分期分为DR轻度组患者115例115眼、DR中度组患者54例54眼、DR重度组患者40例40眼,单纯T2DM未合并DR患者100例100眼为No-DR组,选择同期体检健康人群70例70眼为对照组。所有受检者均行OCTA检查,DR组根据病变程度入组(若双眼病变程度一致,则随机取一眼进行研究),对照组和No-DR组随机一眼纳入研究。比较各组受检者黄斑中心凹无血管区周长(PERIM)、FAZ横径、FAZ竖径、FAZ面积、黄斑中心凹视网膜厚度(MFRT)、非圆度指数(AI)、FAZ周围300μm范围内全层视网膜血流密度(FD-300)、FAZ血管线性密度(VD)变化情况,采用Pearson相关性分析一般资料与FAZ相关指标的相关性,采用受试者工作特征(ROC)曲线评估黄斑FAZ指标诊断DR的价值。结果:DR轻度组、DR中度组、DR重度组患者FBG、MFRT、FAZ面积、PERIM水平均明显高于No-DR组和对照组,AI、VD水平明显低于No-DR组(均P<0.05);No-DR组、DR轻度组、DR中度组、DR重度组患者Cys-C、FAZ横径、FAZ竖径明显高于对照组,FD-300血流密度明显低于对照组(均P<0.05);MFRT与年龄呈正相关(r=0.295,P=0.001);AI、VD与年龄呈负相关(r=-0.296、-0.235,均P<0.05);MFRT、FAZ面积、PERIM、AI、VD诊断DR的曲线下面积(AUC)分别为0.745、0.738、0.696、0.792、0.847。结论:DM患者可出现FAZ结构及微循环改变,FAZ相关参数在诊断早期DR方面具有一定价值。

玻璃体激光消融治疗对黄斑微循环影响的临床研究

研究目的:研究YAG激光消融治疗对生理性玻璃体混浊黄斑微循环的影响。方法:筛选我院32例生理性玻璃体混浊患者,均行YAG激光消融治疗,术前检查最佳矫正视力(BCVA)、非接触眼压、眼部B超、间接眼底镜、OCTA测量黄斑中心凹无血管区(foveal avascular zone,FAZ)面积和黄斑区血流密度(macular vascular density,MVD),观察对比术后30 min、1周、1月、3月、6月以上检查的变化。结果:治疗前后患者的BCVA与非接触眼压无明显差异(P>0.05),玻璃体腔内的混浊物经治疗后明显变小,未发现明显的黄斑拱环形态改变及微血管异常改变。视网膜浅层黄斑区中心、内层、完整区域血管长度密度、血管灌注密度差异均无明显差异(P>0.05)。结论:YAG激光消融治疗能够安全有效改善玻璃体混浊症状,且对患眼视力、眼压和黄斑区微循环无不良影响。

Retinal thickness and vascular parameters using optical coherence tomography in Alzheimer's disease:a meta-analysis

Examining the retinal tissue has the potential to provide a unique method and technique to quantify Alzheimer’s disease-related changes in participants at various stages of the disease.In this metaanalysis,we aimed to investigate the association of various optical coherence tomography parameters with Alzheimer’s disease and whether retinal measurements can be used to diffe rentiate between Alzheimer’s disease and control subjects.Scientific databases including Google Schola r,Web of Science,and PubMed were systematically searched for published articles that evaluated retinal nerve fiber layer thickness and retinal microvascular network in Alzheimer’s disease and control subjects.Seventy-three studies(5850 participants,including 2249 Alzheimer’s disease patients and 3601controls) were included in this meta-analysis.Relative to controls,Alzheimer’s disease patients had a significantly lower global retinal nerve fiber layer thickness(standardized mean difference [SMD]=-0.79,95% confidence intervals [CI]:-1.03 to-0.54,P <0.00001) as well as each quadrant being thinner in Alzheimer’s disease versus controls.Regarding macular paramete rs,values measured by optical coherence tomography were significantly lower in Alzheimer’s disease than controls for macular thickness(pooled SMD:-0.44,95% CI:-0.67 to-0.20,P=0.0003),foveal thickness(pooled SMD=-0.39,95% CI:-0.58 to-0.19,P <0.0001),ganglion cell inner plexiform layer(SMD=-1.26,95% CI:-2.24 to-0.27,P=0.01) and macular volume(pooled SMD=-0.41,95% CI-0.76 to-0.07,P=0.02).Analysis using optical coherence tomography angiography parameters revealed mixed results between Alzheimer’s disease and controls.Superficial vessel density(pooled SMD=-0.42,95% CI:-0.68 to-0.17,P=0.0001) and deep vessel density(pooled SMD=-0.46,95% CI:-0.75 to-0.18,P=0.001) were found to be thinner in Alzheimer’s disease patients whereas the foveal avascular zone(SMD=0.84,95% CI:0.17-1.51,P=0.01) was larger in controls.Vascular density and thickness of various retinal laye rs were decreased in Alzheimer’s disease patients compared to controls.Our results provide evidence for optical coherence tomography technology having the potential to detect retinal and microvascular changes in patients diagnosed with Alzheimer’s disease and aid in monito ring and early diagnosis methods.

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.

Evaluation of macular choroidal and microvascular network changes by activity scores and serum antibodies in thyroid eye patients and healthy subjects

AIM:To investigate the choroidal thickness and the microvascular network changes around the macula in thyroid eye disease(TED)patients at different stages and the relationship of those changes with risk factors,serum antibodies and the severity of TED.METHODS:A total of 85 participants were enrolled.All participants underwent ophthalmology and endocrinology examinations.Subfoveal choroidal thickness(SFCT),superficial(s)and deep(d)foveal avascular zone(FAZ)area,mean(m)and central(c)superficial vascular density(SVD),deep vascular density(DVD)measurements of the enrolled cases were performed with Topcon swept source optical coherence tomography(OCT)/OCT angiography(OCTA)DRI OCT Triton.Multiple linear regression analysis was used to explore the associations between SFCT,FAZ area,SVD,DVD and the relevant factors of TED.RESULTS:Those with active TED patients had higher c-DVD and m-DVD levels(P<0.05),however there is no statistically significant difference in SFCT between active and stable TED patients.Among the serum antibodies,it was observed that s-FAZ and d-FAZ increased,c-SVD and m-SVD decreased in patients with high thyroid stimulating hormone-receptor autoantibodies(TRAB)level,whereas SFCT thickened in patients with high levels of both TRAB and human thyroglobulin(hTG).There was no significant difference in SFCT,FAZ,SVD and DVD measurement at gender,between hyperthyroid and euthyroid patients and among those with or without thyroid papillary carcinoma.CONCLUSION:The results show that both disease activation and serum antibodies differentially affect both superficial and deep retinal vascular density.It has also been shown that high serum antibody levels affect choroidal thickness independent of clinical activity.

Evaluation of childhood developing via optical coherence tomography-angiography in Qamdo,Tibet,China:A prospective cross-sectional,school-based study

BACKGROUND Optical coherence tomography angiography(OCTA)is a new and reliable machine used to evaluate retinal structure and macular perfusion in children.The use of OCTA under bad condition such as high altitude,low atmospheric oxygen,and low humidity,in children is rarely.AIM To quantify the macular micro-vasculature in healthy children of various ages using OCTA in Qamdo.METHODS Design:Prospective cross-sectional,school-based study.Three hundred and fortyseven normal students from 9 schools in 4 different areas in Qamdo were included.OCTA was performed on a 3 mm×3 mm area centered on the macular region and macular cube 512×128 showed details in macular.Early treatment of diabetic retinopathy study Vessel Flow Density(VD)of the macular central vascular plexus density(CVD),inner vascular plexus density(IVD),full vascular plexus density(FVD),and the size of the foveal avascular zone(FAZ)were measured.All these results corrected by t/s=3.382×0.01306×(axial length-1.82).The differences were compared among various ages,sexes and living environments.RESULTS The mean FAZ area in all eyes was 0.27 mm^(2)±0.12 mm^(2).The mean foveal thickness(MFT)in the macular cube was 227.64μm±23.51μm.Compared with girls,boys had a lager FAZ(P=0.0029).Among the different age groups,MFT(P<0.001)and FVD(P<0.0001),IVD(P<0.0001),and CVD(P=0.0050)increased with age.FAZ areas were not correlated with age(P=0.8853)or others(MFT,area).CONCLUSION OCTA can use to evaluate macular perfusion in children.Our data bridge the gap between structural OCT and perfusion density in children in high altitude.Even though these were not a longitudinal study,it may provide us with hints about retina development during puberty and clinical implications of OCTA in children.

Long-Term Postoperative Perfusion Indices in Surgically Resolved Myopic Traction Maculopathy

Background: Pathological myopia can be complicated by the presence of posterior staphyloma, macular atrophy, ruptures in Bruch’s membrane, pathologic choroidal neovascularization, and different degrees of myopic traction maculopathy. Purpose: To report the structural, functional and perfusional outcomes in patients underwent surgery for different stages of myopic traction maculopathy (MTM). Methods: A retrospective, consecutive, comparative, interventional, one-surgeon, case-control study was conducted in 46 eyes of 34 individuals between April 2015 and May 2021. Participants included normal emmetropic eyes (Control emmetropia, n = 25), healthy myopic eyes (Control high myopia, n = 20), and operated and structurally fully resolved myopic eyes with different stages of MTM (Surgically treated group, n = 46). Long-term postoperative functional and perfusional follow-up evaluations were performed with spectral domain-optical coherence tomography (SD-OCT) and OCT angiography. The primary outcome measure included long-term functional, structural and perfusion macular status across groups. Results: Forty-six eyes in 34 patients were included in the study group, with both eyes affected in 12 (26.3%) patients. The mean axial length was 29.89 ± 1.67 mm. The preoperative logMAR was 1.29 ± 0.54 and the postoperative logMAR was 0.60 ± 0.52 (P Conclusion: Compared to emmetropic and healthy myopic eyes, surgically-resolved MTM eyes generally have larger superficial foveal avascular zone area, lower vessel density, smaller choriocapillaris flow area, thinner central subfoveal thickness, and more macular defects. Eyes with stage III or IV MTM had larger deviation compared to eyes at earlier stages. Visual function change after surgery was associated with superficial foveal avascular zone area. Better functional, structural and perfusion index outcomes were observed when highly myopic eyes underwent early surgery.

OCTA定量分析糖尿病视网膜病变患者黄斑区微循环变化

目的:通过光学相干断层扫描血管成像(OCTA)技术,评估糖尿病视网膜病变(DR)患者黄斑区微循环变化,并对可能影响黄斑区微循环的危险因素进行分析,为DR早期筛查、诊断及治疗干预提供临床依据。方法:回顾性研究。收集2022-05/10于西安市中心医院眼科门诊及病房就诊的2型糖尿病患者75例75眼,分为无DR(NDR)组28眼、非增殖型DR(NPDR)组25眼、增殖型DR(PDR)组22眼。应用OCTA对黄斑区视网膜行3mm×3mm血流成像扫描,自动获得浅层视网膜黄斑中心凹区、黄斑旁中心凹区(1~3mm)以及黄斑区3mm×3mm的血管密度(VD)和黄斑中心凹无血管区(FAZ)面积,分析黄斑区各参数在不同程度DR患者中的变化。结果:与NDR组相比,PDR组和NPDR组患者黄斑区3mm×3mm浅层视网膜毛细血管(SCP)的VD降低(均P<0.017),并且黄斑旁中心凹VD在各象限均降低(P<0.017),以PDR组降低最为显著。PDR组和NPDR组患者FAZ面积明显大于NDR组(P<0.017)。DR患者的年龄、同型半胱氨酸、最佳矫正视力(LogMAR)、眼轴、糖化血红蛋白(HbA1c)与黄斑中心凹区VD呈负相关(P<0.05),同型半胱氨酸、最佳矫正视力(LogMAR)、眼轴、糖尿病病程与黄斑区3mm×3mm VD呈负相关(P<0.05),甘油三酯、最佳矫正视力(LogMAR)、HbA1c与黄斑旁中心凹区VD呈负相关(P<0.05),总胆固醇、CMT与VD无明显相关(P>0.05)。结论:OCTA可以监测到DR患者黄斑区微循环变化,DR患者的全身情况与黄斑区微循环密切相关。

正常眼压性青光眼患者黄斑区血流灌注状态与视野缺损的相关性研究

目的观察正常眼压性青光眼(NTG)患者黄斑区血流灌注状态,分析其与视野缺损之间的相关性。方法纳入2020年1月—2021年2月就诊于上海中医药大学附属曙光医院的符合纳入标准的NTG患者70例(70只眼)作为观察组,选取同期同医院就诊的同年龄段的健康志愿者49例(49只眼)作为对照组。采集受试者黄斑区视网膜浅层血管线性密度(MSRVLD)、黄斑区视网膜浅层血管灌注密度(MSRPD)、黄斑中心凹无血管区面积(FAZ)及观察组患者的视野平均缺损(MD),并对以上数据进行统计学分析。结果(1)MSRVLD:观察组黄斑区下方及鼻侧较对照组下降,差异均有统计学意义(t_(下方)=4.041,P=0.000;t_(鼻侧)=2.945,P=0.004)。(2)MSRPD:观察组黄斑区下方及鼻侧较对照组下降,差异均有统计学意义(t_(下方)=3.291,P=0.001;t_(鼻侧)=2.924,P=0.004)。(3)黄斑中心凹FAZ:观察组黄斑中心凹FAZ面积为(0.21±0.13)mm^(2),对照组为(0.23±0.17)mm^(2)。2组比较,差异无统计学意义(P>0.05)。(4)相关性分析:观察组MD与MSRVLD、MSRPD呈正相关(r_(MSRVLD)=0.387,r_(MSRPD)=0.402,均P=0.001)。结论NTG患者黄斑区存在血流灌注不足,且与MD相关。

OCTA检测高度近视患者视网膜脉络膜厚度及血流变化的研究进展

高度近视是指近视度数在-6.00D以上的一种屈光不正状态。由于高度近视常常伴随多种眼底病理性改变,因此高度近视患者的视功能受到不同程度损害。光学相干断层扫描血管成像(OCTA)作为一种新兴的眼科辅助检查手段,可以高效、无创地得到视网膜、脉络膜的微血管分层图像,并对血流信号进行量化分析。自OCTA问世以来,运用OCTA观察高度近视眼底改变的研究层出不穷。本文通过对OCTA检测高度近视患者视网膜脉络膜厚度及血流变化的研究现状进行综述,以期揭示高度近视与视网膜脉络膜厚度、血流密度以及中心凹无血管区面积等参数的相关性,为科研人员深入探索高度近视发生机制,延缓高度近视发生发展提供思路。

光学相干断层血管造影成像应用于非增殖期糖尿病视网膜病变微血管的临床筛查

目的探讨光学相干断层血管造影成像(OCTA)应用于非增殖期糖尿病视网膜病变(NPDR)患者视网膜微血管筛查中的临床效果。方法选取在苏州大学附属第三医院确诊的30例NPDR患者(NPDR组)和30例健康志愿者(对照组)行OCTA检查,对其黄斑中心凹无血管区(FAZ)的面积、周长、圆度变化以及黄斑区视网膜浅层毛细血管层(SCP)和视盘盘周放射状毛细血管层(RPC)上侧、下侧、鼻侧、颞侧4个象限的血流密度进行量化分析。结果NPDR组患者黄斑区SCP和视盘RPC 4个象限的血流密度较对照组均显著下降(43.68±3.03vs.46.98±3.04、42.79±3.17vs.50.45±2.25、43.21±2.67vs.47.44±2.42、44.21±3.22vs.51.72±5.32、46.43±3.54vs.53.02±2.62、45.97±3.67vs.52.53±2.82、44.63±2.73vs.48.19±3.67、41.73±3.15vs.45.12±3.31),差异均有统计学意义(均P<0.01)。NPDR组患者FAZ面积和周长较正常对照组均明显增大[(0.50±0.06vs.0.43±0.47)mm2、(3.10±0.21vs.2.87±0.22)mm],圆度较对照组明显变小[(0.63±0.05vs.0.67±0.05)%],差异也均有统计学意义(均P<0.01)。结论OCTA可检测出NPDR的早期视网膜微结构改变,可作为NPDR的辅助筛查,为早期诊治提供信息。