Reduced Macular Vascular Density in Myopic Eyes

Background： Morphological changes of the vasculature system in patients with myopia have been observed by Doppler ultrasound and fundus fluorescein angiography （FFA）; however, these studies have limitations. Doppler ultrasound provides low-resolution images which are mainly obtained from visualized large vessels, and FFA is an invasive examination. Optic coherence tomography （OCT） angiography is a noninvasive, high-resolution measurement for vascular density. The purpose of this study was to investigate the change of vascular density in myopic eyes using OCT angiography. Methods： This cross-sectional study includes a total of 91 eyes ~Yom 47 participants including control, moderate, and high myopia that were evaluated by OCT angiography. Patients with myopia were recruited from the Refractive Department, Shenzhen Aier Eye Hospital, from August 5, 2015 to April 1, 2016. Emmetropic eyes were from healthy volunteers. The vascular density at macula and optic disc regions, ganglion cell complex （GCC） thickness, and retinal nerve fiber layer （RNFL） thickness were measured. Their relationships with axial length （AL） and refractive error were analyzed. One-way analysis of variance （ANOVA）, Pearson＇s correlation, and generalized estimating equation were used for statistical analysis, Results： Both superficial and deep macular vascular density were highest in control （25.64% ± 3.76% and 37.12% ± 3.66%, respectively）, then in moderate myopia （21.15% ± 5.33% and 35.35% ± 5.50%, respectively）, and lowest in high myopia group （ 19.64% ± 3.87% and 32.81% ± 6.29%, respectively） （F =13.74 and 4.57, respectively; both P 〈 0.001）. Both superficial （β = -0.850 and 0.460, respectively） and deep （β = -0.766 and 0.396, respectively） macular vascular density were associated with AL and spherical equivalent （all P 〈 0.001 ）. Superficial macular vascular density was associated with GCC thickness （β = 0.244, P = 0.040）, independent of spherical equivalent. The vascular density in optic disc region had no difference among the three groups, and it was not associated with AL, spherical equivalent, or RNFL thickness. Conclusion： Our results suggested that with the increase of myopia, the vascular density decreased in macular region, but not in optic disc region.

Quantitative study of peripapillary retinal nerve fiber layer thickness and peripapillary vessel density in patients with different stages of Parkinson's disease

AIM: To observe the changes in the thickness of peripapillary retinal nerve fiber layer(p RNFL) and peripapillary vessel density(pVD) in patients with different stages of Parkinson's disease(PD).METHODS: Totally 47 patients(47 eyes) with primary PD were divided into the mild group and the moderateto-severe group according to Hoehn & Yahr(H&Y) stage. Among them, there were 27 cases(27 eyes) in mild group and 20 cases(20 eyes) in moderate-to-severe group. And 20 cases(20 eyes) who were included in the control group were healthy people who came to our hospital for health screening at the same time. All participants underwent optical coherence tomography angiography(OCTA) examinations. The pRNFL thickness, total vessel density(tVD) and capillary vessel density(cVD) of the optic disc in average, superior half, inferior half, superior nasal(SN), nasal superior(NS), nasal inferior(NI), inferior nasal(IN), inferior temporal(IT), temporal inferior(TI), temporal superior(TS), and superior temporal(ST) were measured. One-way ANOVA was used to compare the differences of optic disc parameters among the three groups, and Pearson and Spearman correlations were used to analyze the correlation between pRNFL, pVD and the disease duration, H&Y stage and UPDRS-Ⅲ score in patients with PD, respectively.RESULTS: There were significant differences in p RNFL thickness in average, superior half, inferior half, SN, NS, IN, IT and ST quadrants among the three groups(P<0.05). In PD group, the pRNFL thickness in average, superior half, inferior half, NS and IT quadrants were negatively correlated with H&Y stage and UPDRS-Ⅲ score, respectively(P<0.05). There were statistically significant differences in the cVD of whole image, inferior half, NI and TS quadrants, the tVD of the whole image, inferior half, and peripapillary among the three groups(P<0.05). In PD group, the tVD of whole image and the c VD of NI and TS quadrants were negatively correlated with the H&Y stage, respectively(P<0.05);the cVD of TS quadrant was negatively correlated with UPDRS-Ⅲ score(P<0.05).CONCLUSION: The thickness of pRNFL in PD patients is significantly decreased, and it is negatively correlated with H&Y stage and UPDRS-Ⅲ score. With the increase of the severity of the disease, the pVD parameters in PD patients increase at first in the mild group, and then decrease in the moderate-to-severe group, and negatively correlate with H&Y stage and UPDRS-Ⅲ score.

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.

Peripapillary and macular vascular densities in healthy,ocular hypertensive,and different stages of glaucomatous eyes

AIM:To investigate vascular changes in different stages of glaucoma and to evaluate the role of optical coherence tomography angiography(OCTA)in the early diagnosis of glaucoma.METHODS:Glaucoma patients and healthy controls(n=29 eyes)were investigated in this cross-sectional comparative study.Glaucoma patients were grouped as ocular hypertension(n=44 eyes),preperimetric glaucoma(PPG;n=32 eyes),early glaucoma(EG;n=35 eyes),moderate stage glaucoma(MG;n=36 eyes),and advanced glaucoma(AG;n=35 eyes).Peripapillary and macular vascular densities(VDs)of all participants were compared and correlations of VDs and retinal nerve fiber layer thickness(RNFLT),ganglion cell analysis(GCA),and visual field(VF)tests were evaluated.Area under the receiver operation characteristic curves(AUC)of the peripapillary and macular VD parameters were obtained.RESULTS:VD values decreased with the progression of glaucoma.Most peripapillary and macular VD parameters of PPG and EG groups were lower than healthy controls(P<0.001).There was no significant difference in RNFLT between the PPG and EG groups,but most peripapillary and macular VDs were found to be lower in EG group than in PPG group(P<0.05).In most disease group,VDs were significantly correlated with OCT parameters(P<0.001)and VF index(P<0.05).There were no significant correlations between VF and RNFLT indices in the AG group,but significant correlations were found between VF and VD values(P<0.05).AUC for discriminating between healthy and glaucomatous eyes were highest in whole image peripapillary VD(AUC:0.865,0.929,and 0.986,respectively in EG,MG,and AG groups).CONCLUSION:OCTA can be used in the early diagnosis of glaucoma and can be useful in follow-up of the advanced disease.In cases where limitations or suspicions in structural and functional tests are present,OCTA can be used as a supportive diagnostic test,both in EG and AG.

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.

Comparison of OCT and OCTA manifestations among untreated PCV, neovascular AMD, and CSC in Chinese population

AIM: To compare the qualitative and quantitative features among untreated polypoidal choroidal vasculopathy(PCV), neovascular age-related macular degeneration(nv-AMD) and central serous chorioretinopathy(CSC) using optical coherence tomography(OCT) and OCT angiography(OCTA).METHODS: This retrospective study included 16 eyes with thin-choroid PCV, 18 eyes with thick-choroid PCV, 16 eyes with nv-AMD and 17 eyes with CSC, respectively. The indicators were obtained by OCT and OCTA.RESULTS: Sub-foveal choroidal thickness(SFCT) in CSC was thicker compared to other groups(all P<0.05). SFCT in nv-AMD was thicker compared to thin-choroid PCV, but thinner compared with thick-choroid PCV(both P<0.05). As the ratio of thickness of Haller's layer to thickness of SFCT, which of thin-choroid PCV was significantly higher than CSC(P<0.001). Likewise, thick-choroid PCV had significantly higher ratio than nv-AMD(P=0.016) or CSC(P<0.001). There were differences among them in pigment epithelium detachment(PED). The whole-superficial retinal vessel density(RVD), deep RVD and choroidal capillary vessel density(CCVD) in CSC were significantly higher compared to other three groups, respectively(all P<0.05). The whole CCVD in nv-AMD was higher compared to thick-choroid PCV(P=0.032). Cross-sectional local angiographic form was 87.50%, 83.33%, 0 and 35.29% in thin-choroid PCV, thickchoroid PCV, nv-AMD and CSC, respectively. Cross-sectional diffuse angiographic form was 12.50%, 16.67%, 100% and 5.88% in thin-choroid PCV, thick-choroid PCV, nv-AMD and CSC, respectively.CONCLUSION: Combination of OCT and OCTA can effectively observe the significant alterations existed in PCV, CSC and nv-AMD, and there are distinctive differences among them. The pathogenesis is not exactly the same between PCV and nv-AMD, or PCV and CSC.

The pleiotropic vasoprotective functions of high density lipoproteins(HDL)

The pleiotropic functions of circulating high density lipoprotein（HDL） on peripheral vascular health are well established. HDL plays a pivotal role in reverse cholesterol transport and is also known to suppress inflammation,endothelial activation and apoptosis in peripheral vessels. Although not expressed in the central nervous system, HDL has nevertheless emerged as a potential resilience factor for dementia in multiple epidemiological studies. Animal model data specifically support a role for HDL in attenuating the accumulation of P-amyloid within cerebral vessels concomitant with reduced neuroinflammation and improved cognitive performance. As the vascular contributions to dementia are increasingly appreciated, this review seeks to summarize recent literature focused on the vasoprotective properties of HDL that may extend to cerebral vessels, discuss potential roles of HDL in dementia relative to brainderived lipoproteins, identify gaps in current knowledge, and highlight new opportunities for research and discovery.

Changes of optic nerve head microcirculation in high myopia

AIM:To analyze the correlation of age,spherical equivalent(SE),and axial length(AL)with the microcirculation of optic nerve head(ONH)in high myopia(HM).METHODS:In this cross-sectional clinical study,164 right eyes were included.Optical coherence tomography angiography(OCTA)was used to detect ONH vessel density.Eyes were classified based on age,SE,and AL.Groups of Age1,Age2,and Age3 were denoted for age classification(Age1<20y,20y≤Age2<30y,Age3≥30y);Groups SE1,SE2,and SE3 for the SE classification(-9≤SE1<-6 D,-12≤SE2<-9 D,SE3<-12 D);Groups AL1,AL2,AL3,and AL4 for the AL classification(AL1<26 mm,26≤AL2<27 mm,27≤AL3<28 mm,AL4≥28 mm).RESULTS:No significant difference was observed in vessel density among the Age1,Age2,and Age3 groups(all P>0.05)and the SE1,SE2,and SE3 groups(all P>0.05).No significant difference was observed in the intrapapillary vascular density(IVD)among AL1,AL2,AL3,and AL4 groups(P>0.05).However,a significant decrease was found in the peripapillary vascular density(PVD)in the AL1,AL2,AL3,and AL4 groups(F=3.605,P=0.015),especially in the inferotemporal(IT;F=6.25,P<0.001),temporoinferior(TI;F=2.865,P=0.038),and temporosuperior(TS;F=6.812,P<0.001)sectors.The IVD was correlated with age(r=-0.190,P<0.05)but not with SE or AL(P>0.05).The PVD was correlated with AL(r=-0.236,P<0.01)but not with age or SE(P>0.05).CONCLUSION:With the increase of AL,the IVD remains stable while the PVD decreases,especially in the three directions of temporal(IT,TI,and TS).The main cause of microcirculation reduction may be related to AL elongation rather than an increase in age or SE.

Longitudinal analysis of quantitative biomarkers using projection-resolved OCT angiography in retinal vein occlusion

Background:To evaluate a fully automated vascular density(VD),skeletal density(SD)and fractal dimension(FD)method for the longitudinal analysis of retinal vein occlusion(RVO)eyes using projection-resolved optical coherence tomography angiography(OCTA)images and to evaluate the association between these quantitative variables and the visual prognosis in RVO eyes.Methods:Retrospective longitudinal observational case series.Patients presenting with RVO to Creteil University Eye Clinic between October 2014 and December 2018 and healthy controls were retrospectively evaluated.Group 1 consisted of central RVO(CRVO)eyes,group 2 consisted of eyes with branch RVO(BRVO)and group 3 of healthy control eyes.OCTA acquisitions(AngioVue RTVue XR Avanti,Optovue,Inc.,Freemont,CA)were performed at baseline and last follow up visit.VD,SD,and FD analysis were computed on OCTA superficial and deep vascular complex(SVC,DVC)images at baseline and final follow up using an automated algorithm.Logistic regression was performed to find if and which variable(VD,SD,FD)was predictive for the visual outcome.Results:Forty-one eyes,of which 21 consecutive eyes of 20 RVO patients(13 CRVO in group 1,8 BRVO in group 2),and 20 eyes of 20 healthy controls were included.At the level of SVC,VD and FD were significantly lower in RVO eyes compared to controls(P<0.0001 and P=0.0008 respectively).Best-corrected visual acuity(BCVA)at last follow-up visit was associated with baseline VD(P=0.013),FD(P=0.016),and SD(P=0.01)at the level of the SVC,as well as with baseline FD at the DVC level(P=0.046).Conclusions:Baseline VD,SD,and FD are associated with the visual outcome in RVO eyes.These parameters seem valuable biomarkers and may help improve the evaluation and management of RVO patients.

Expression levels and significance of hypoxia inducible factor-1 alpha and vascular endothelial growth factor in human colorectal adenocarcinoma

Background Hypoxia-inducible factor 1 (HIF-1), a transcription factor, is overexpressed in common human cancers and their metastases. This study aimed at determining the expression levels of HIF-1α and vascular endothelial growth factor (VEGF) in SW480 cells and in colorectal adenocarcinoma tissue and ascertaining whether HIF-1α and VEGF play important roles in tumor angiogenesis. Methods HIF-1α mRNA expression was analyzed using in situ hybridization and RT-PCR. HIF-1α and VEGF protein were detected in SW480 cells and colorectal adenomas and adenocarcinomas by immunohistochemistry using streptavidin/peroxidase (SP). Western blot was used to detect HIF-1α protein extracted from SW480 cells. Microvessel density (MVD) in colorectal carcinomas was determined by anti-CD_ 34 immunostaining in colorectal carcinomas. Results Optical density values representing HIF-1α mRNA expression levels were found to be significantly higher in SW480 cells in hypoxic conditions than in cells under normoxic conditions (P<0.05) or in hypoxic conditions but treated with genistein (P<0.05). The levels of HIF-1α and VEGF protein expression in SW480 cells were significantly higher in the hypoxia group than in the normoxia group (P<0.01, P<0.05, respectively) and hypoxia/genistein group (P<0.01, P<0.05, respectively). The positive expression rates of HIF-1α mRNA changed dramatically when comparing colorectal adenomas with adenocarcinomas of different Dukes’ stages (P<0.05). HIF-1α mRNA was also expressed at higher levels in adenocarcinomas than that in adenomas (P<0.01). HIF-1α protein expression correlated significantly with VEGF protein expression and MVD.Conclusions Hypoxia induces the expression of HIF-1α and VEGF in colorectal adenocarcinomas. HIF-1α may play an important role in angiogenesis and tumor progression by regulating the expression of VEGF in human colorectal carcinomas.