Three-dimensional choroidal vascularity index and choroidal thickness in fellow eyes of acute and chronic primary angle-closure using swept-source optical coherence tomography

AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of normal controls.METHODS:This study included 37 patients with unilateral APAC,37 with asymmetric CPACG without prior treatment,and 36 healthy participants.Using swept-source optical coherence tomography(SS-OCT),the macular and peripapillary choroidal thickness and three-dimensional CVI were measured and compared globally and sectorally.Pearson’s correlation analysis and multivariate regression models were used to evaluate choroidal thickness or CVI with related factors.RESULTS:The mean subfoveal CVIs were 0.35±0.10,0.33±0.09,and 0.29±0.04,and the mean subfoveal choroidal thickness were 315.62±52.92,306.22±59.29,and 262.69±45.55μm in the F-APAC,F-CPACG,and normal groups,respectively.All macular sectors showed significantly higher CVIs and choroidal thickness in the F-APAC and F-CPACG eyes than in the normal eyes(P<0.05),while there were no significant differences between the F-APAC and F-CPACG eyes.In the peripapillary region,the mean overall CVIs were 0.21±0.08,0.20±0.08,and 0.19±0.05,and the mean overall choroidal thickness were 180.45±54.18,174.82±50.67,and 176.18±37.94μm in the F-APAC,F-CPACG,and normal groups,respectively.There were no significant differences between any of the two groups in all peripapillary sectors.Younger age,shorter axial length,and the F-APAC or F-CPACG diagnosis were significantly associated with higher subfoveal CVI and thicker subfoveal choroidal thickness(P<0.05).CONCLUSION:The fellow eyes of unilateral APAC or asymmetric CPACG have higher macular CVI and choroidal thickness than those of the normal controls.Neither CVI nor choroidal thickness can distinguish between eyes predisposed to APAC or CPACG.A thicker choroid with a higher vascular volume may play a role in the pathogenesis of primary angle-closure glaucoma.

Using choroidal thickness to detect myopic macular degeneration

AIM:To explore the usage of choroidal thickness measured by swept-source optical coherence tomography(SS-OCT)to detect myopic macular degeneration(MMD)in high myopic participants.METHODS:Participants with bilateral high myopia(≤−6 diopters)were recruited from a subset of the Guangzhou Zhongshan Ophthalmic Center-Brien Holden Vision Institute High Myopia Cohort Study.SS-OCT was performed to determine the choroidal thickness,and myopic maculopathy was graded by the International Meta-Analysis for Pathologic Myopia(META-PM)Classification.Presence of MMD was defined as META-PM category 2 or above.RESULTS:A total of 568 right eyes were included for analysis.Eyes with MMD(n=106,18.7%)were found to have older age,longer axial lengths(AL),higher myopic spherical equivalents(SE),and reduced choroidal thickness in each Early Treatment Diabetic Retinopathy Study(ETDRS)grid sector(P<0.001).The area under the receiver operating characteristic(ROC)curves(AUC)for subfoveal choroidal thickness(0.907)was greater than that of the model,including age,AL,and SE at 0.6249,0.8208,and 0.8205,respectively.The choroidal thickness of the inner and outer nasal sectors was the most accurate indicator of MMD(AUC of 0.928 and 0.923,respectively).An outer nasal sector choroidal thickness of less than 74μm demonstrated the highest odds of predicting MMD(OR=33.8).CONCLUSION:Choroidal thickness detects the presence of MMD with high agreement,particularly of the inner and outer nasal sectors of the posterior pole,which appears to be a biometric parameter more precise than age,AL,or SE.

Evaluation of retinal and choroidal thickness changes in overweight and obese adults without ocular symptoms by swept-source optical coherence tomography

AIM:To evaluate the relationship of overweight and obesity with retinal and choroidal thickness in adults without ocular symptoms by swept-source optical coherence tomography(SS-OCT).METHODS:According to the body mass index(BMI)results,the adults enrolled in the cross-sectional study were divided into the normal group(18.50≤BMI<25.00 kg/m^(2)),the overweight group(25.00≤BMI<30.00 kg/m^(2)),and the obesity group(BMI≥30.00 kg/m^(2)).The one-way ANOVA and the Chi-square test were used for comparisons.Pearson’s correlation analysis was used to evaluate the relationships between the measured variables.RESULTS:This research covered the left eyes of 3 groups of 434 age-and sex-matched subjects each:normal,overweight,and obesity.The mean BMI was 22.20±1.67,26.82±1.38,and 32.21±2.35 kg/m^(2) in normal,overweight and obesity groups,respectively.The choroid was significantly thinner in both the overweight and obesity groups compared to the normal group(P<0.05 for all),while the retinal thickness of the three groups did not differ significantly.Pearson’s correlation analysis showed that BMI was significantly negatively correlated with choroidal thickness,but no significant correlation was observed between BMI and retinal thickness.CONCLUSION:Choroidal thickness is decreased in people with overweight or obesity.Research on changes in choroidal thickness contributes to the understanding of the mechanisms of certain ocular disorders in overweight and obese adults.

Non-linear relationship between age and subfoveal choroidal thickness in Chinese patients with proliferative diabetic retinopathy

BACKGROUND No study has investigated the change regularity between age and subfoveal choroidal thickness(SFCT)in proliferative diabetic retinopathy(PDR).AIM To investigate the relationship between the SFCT and age in Chinese patients with PDR.METHODS This was a cross-sectional retrospective study.The participants were hospitalized individuals with type 2 diabetes who underwent vitrectomy for PDR.Contralateral eyes that met the criteria were included in the study.All necessary laboratory tests were performed at the time of admission.Central macular thickness(CMT)and SFCT were two quantitative assessments made using enhanced depth imaging optical coherence tomography.CMT was measured automatically and SFCT was measured manually with digital calipers provided by the Heidelberg Eye Explorer software.RESULTS The final analysis included a total of 234 individuals with PDR.The average age was 55.60 years old±10.03 years old,and 57.69%of the population was male.Univariate analysis revealed a significant negative connection between age and SFCT in patients with PDR[β=-2.44,95%confidence interval(95%CI):-3.46 to-1.42;P<0.0001].In the fully adjusted model,the correlation between SFCT and age remained steady(β=-1.68,95%CI:-2.97 to-0.39;P=0.0117).Spline smoothing showed that the relationship between SFCT and age in patients with PDR was non-linear,with an inflection point at 54 years of age.CONCLUSION Our findings suggest that age is a key determinant of choroidal thickness.The non-linear link between SFCT and age in PDR patients should be taken into account.

Automatic fovea detection and choroid segmentation for choroidal thickness assessment in optical coherence tomography

AIM:To develop an automated model for subfoveal choroidal thickness(SFCT)detection in optical coherence tomography(OCT)images,addressing manual fovea location and choroidal contour challenges.METHODS:Two procedures were proposed:defining the fovea and segmenting the choroid.Fovea localization from B-scan OCT image sequence with three-dimensional reconstruction(LocBscan-3D)predicted fovea location using central foveal depression features,and fovea localization from two-dimensional en-face OCT(LocEN-2D)used a mask region-based convolutional neural network(Mask R-CNN)model for optic disc detection,and determined the fovea location based on optic disc relative position.Choroid segmentation also employed Mask R-CNN.RESULTS:For 53 eyes in 28 healthy subjects,LocBscan-3D’s mean difference between manual and predicted fovea locations was 170.0μm,LocEN-2D yielded 675.9μm.LocEN-2D performed better in non-high myopia group(P=0.02).SFCT measurements from Mask R-CNN aligned with manual values.CONCLUSION:Our models accurately predict SFCT in OCT images.LocBscan-3D excels in precise fovea localization even with high myopia.LocEN-2D shows high detection rates but lower accuracy especially in the high myopia group.Combining both models offers a robust SFCT assessment approach,promising efficiency and accuracy for large-scale studies and clinical use.

Beta-alanine promotes angiogenesis in laser-induced choroidal neovascularization mice models

AIM:To investigate the effect ofβ-alanine(BA)on laserinduced choroidal neovascularization(CNV)mice models.METHODS:Laser-induced CNV mice models were established,and BA was administrated for one week and two weeks in advance,separately.Furthermore,retinal pigment epithelium(RPE)-choroid flat mounts were separated,and immunohistochemical staining was performed.The laser-induced CNV lesion areas were measured and compared.In addition,liver and kidney morphologies were observed to identify potential hepatorenal toxicity.RESULTS:Enlarged CNV lesion areas were observed in the BA treated group.No significant differences were observed in the liver and kidney sections between groups.CONCLUSION:BA treatment increase CNV lesion areas,suggesting the detrimental effects of BA as a nutritional supplement in age-related macular degeneration(AMD)population.

Impact of multifocal gas-permeable lens designs on short-term choroidal response, axial length, and retinal defocus profile

AIM:To investigate the impact of multifocal gas permeable contact lens(MFGPCL)in various add power and distance/near area allocation on short-term changes of choroidal thickness(ChT),axial length(AL),and retinal defocus profile in young adults.METHODS:Seventeen young adults(2 males and 15 females;age 23.17±4.48y)were randomly assigned to wear two designs binocularly with a one-week washout period in between.Total of four MFGPCL designs were assessed.All designs were distance-center that varied in two add power(+1.50 and 3.00 D)and/or two distance zone(DZ)diameters(1.50 and 3.00 mm;design A:DZ 1.5/add 3.0,B:DZ 1.5/add 1.5,C:DZ 3.0/add 3.0,D:DZ 3.0/add 1.5).ChT,AL,and peripheral refraction data were collected on each subject at baseline,on days 1 and 7 of MFGPCL daily wear.ChT was assessed in four quadrants using a spectraldomain optical coherence tomography.RESULTS:AL was shortened by-26±44μm with lens C,-18±27μm with lens D,-13±29μm with lens A,and-8±30μm with lens B(all P<0.05).A significant overall increase in ChT was observed with all 4 designs(lens A:+6±6μm,B:+3±7μm,C:+8±7μm,and D:+8±7μm).Temporal and superior choroid exhibited more choroidal thickening associated with MFGPCL.All designs induced significant relative peripheral myopia(RPM)beyond the central 20o across the horizontal meridian in both nasal and temporal fields(P<0.05).CONCLUSION:MFGPCLs show a significant influence on ChT and AL,which are associated with significant increase in RPM after short-term wear.The reliability and feasibility of quantifying short-term changes in ChT support its use as a promising marker for the long-term efficacy of myopia-controlling treatments.

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.

Detecting early changes in choroidal vascularity and thickness using optical coherence tomography in patients with corneal crosslinking for keratoconus

AIM:To investigate changes in choroidal thickness and vascularity in keratoconus patients treated with corneal crosslinking.METHODS:This study evaluated 28 eyes of 22 patients with keratoconus who underwent corneal crosslinking.The choroidal thicknesses were evaluated on enhanced depth imaging optical coherence tomography at the preoperative and postoperative 3d,1,and 3mo.Choroidal thickness in the four cardinal quadrants and the fovea were evaluated.The choroidal vascularity index was also calculated.RESULTS:There was no significant difference in central choroidal thickness between the preoperative and postoperative 3d,1mo(P>0.05).There was a significant increase in the 3mo(P=0.034)and a significant decrease in the horizontal choroidal vascularity index on the postoperative 3d(P=0.014),there was no statistically significant change in vertical axes and other visits in horizontal sections(P>0.05).CONCLUSION:This study sheds light on choroidal changes in postoperative corneal crosslinking for keratoconus.While it suggests the procedure’s relative safety for submacular choroid,more extensive research is necessary to confirm these findings and their clinical significance.

Etiology of anterior choroidal artery infarction:a systematic review

Objective:To systematically review the etiology of anterior choroidal artery(AChA)infarction.Methods:A systematic literature search up to May 11,2024,for AChA infarction with its etiology.Epidemiologic and clinical data of patients,anatomic distribution of the lesions,and etiologic classification of AChA infarction were extracted.Results:A total of 1007 individual patient data was included(967 from retrospective clinical studies and 40 from case reports).Among the clinical research,patients’mean age was 64.7.There were 62.24%of male and 37.76%of female patients.Hypertension(66.04%)was the most common risk factor for patients with AChA infarction.Dyslipidemia(32.92%),diabetes mellitus(30.93%),and smoking(26.54%)were also common risk factors.Moreover,the posterior limb of the internal capsule was the most frequently affected structure.Undetermined etiology(n=173,38.02%),according to the trial of org 10172 in acute stroke treatment(TOAST)etiological classification,was the most common etiology,followed by small vessel disease(n=117,25.71%),large artery atherosclerosis(n=84,18.46%),and cardioembolism(n=63,13.85%).Furthermore,eighteen strokes were caused by other determined etiologies(3.96%).Conclusions:Undetermined etiology was the most common etiology of AChA infarction.Hypertension,dyslipidemia,diabetes mellitus,and smoking were common risk factors for patients with AChA infarction.It is necessary to prevent the risk factors.

Vitrectomy, lensectomy and silicone oil tamponade in the management of retinal detachment associated with choroidal detachment

AIM: To report the results of combined vitrectomy, lensectomy and silicone oil (SO) tamponade in treating primary rhegmatogenous retinal detachment (RRD) associated with choroidal detachment (CD). · METHODS: A retrospective, consecutive and case series study of 21 subjects with concurrent RRD associated with CD was conducted. All subjects underwent a standard three -port 20G pars plana vitrectomy (PPV) with lensectomy and silicone oil tamponade. Mean follow -up time was 8 months (rang from 4 to 19 months). The primary and final anatomic success rate, visual acuity and final intraocular pressure (IOP) were recorded and analyzed. ·RESULTS: Of 21 subjects, 8 were women and 13 were men. Age at presentation ranged from 22 to 75 years (mean 57.4 years). The presenting vision ranged from light perception to 0.15. The initial IOP ranged from 3mmHg to 12mmHg (mean 6.2mmHg). All eyes were phakic except one pseudophakic. No intraocular lens was implanted during the primary surgical intervention. Fifteen of 21 (71.4%) eyes had retina reattached after one operation. Six eyes had recurrent inferior retinal detachment due to proliferation. Five of them were successfully reattached after one or more additional operations. Mean IOP at final follow -up was 15.2mmHg (range from 8mmHg to 20mmHg). One case declined for further operation. The final reattachment rate was 95.2%. Visual acuity improved in 19 (90.5%) eyes, was unchanged in 1 (4.8%) eye and decreased in 1 (4.8%) eye.·CONCLUSION: Combination of vitrectomy, lensectomy and silicone tamponade is an effective method in treating RRD associated with CD, reducing the incidence of postoperative hypotony.

Change in subfoveal choroidal thickness after argon laser panretinal photocoagulation

AIMTo evaluate changes in subfoveal choroidal thickness (SFCT) and macular thickness as measured by enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT) after argon laser panretinal photocoagulation (PRP) in patients with severe diabetic retinopathy.

Risk factors of rhegmatogenous retinal detachment associated with choroidal detachment in Chinese patients

AIM： To comprehensively analyze the risk factors of rhegmatogenous retinal detachment （RRD） associated with choroidal detachment （CD）. METHODS： A total of 265 eyes of 265 consecutive cases of RRD were retrospectively analyzed. All patients had systemic and ophthalmologic examination. CD was diagnosed by indirect ophthalmoscopy, B -scan ultrasonography, and ultrasound biomicroscope （UBM）. Each parameter was compared between patients of RRD and rhegmatogenous retinal detachment associated with choroidal detachment （RRDCD）. Logistic regression analysis was used to determine the independent risk factors of CD. RESULTS： There were 52 eyes （19.62%） with CD. Pseudophakia was more commonly seen in RRDCD （21.15% ys6.10%, P=0.002）. Intraocular pressure （lOP） was lower （8.60 ±3.62 ys 12.96 ±3.55, P 〈0.001）, best - corrected visual acuity was worse [3.00 （2.00 to 3.00） vs 1.92 （1.22 to 3.00）, P=-0.001], and refractive error was more myopic [-4 （-9 to -2） vs -2 （-6 to 0）, P=0.007] in RRDCD. Eyes with RRDCD had larger extent of retinal detachment （P=0.007）. In RRDCD, 34.62% of eyes presented with multiple holes （P=0.044） and 25.00% with macular holes （P=0.012）, compared with 20.66% and 14.08% in R RD. High myopia （P=0.039）, low lOP （P=0.017）, and larger extent of retinal detachment （P〈0.001） were significant and independent risk factors for developing CD. - CONCLUSION： For CD in RRD, related factors include BCVA, lOP, lens status, refractive error, extent of retinal detachment, number of holes, and macular hole. Larger extent of retinal detachment, high myopia, and low lOP are significant and independent risk factors.

Choroidal and cutaneous metastasis from gastric adenocarcinoma

Choroidal or cutaneous metastasis of gastric cancer is rare. Gastrointestinal cancer was found in only 4% in patients with uveal metastasis. Choroidal metastasis from gastric cancer was reported in two cases in earlier literature. The frequency of gastric cancer as a primary lesion was 6% in cutaneous metastasis of men, and cutaneous metastasis occurs in 0.8% of all gastric cancers. We report a patient with gastric adenocarcinoma who presented with visual disorder in his left eye and skin pain on his head as his initial symptoms. These symptoms were diagnosed to be caused by choroidal and cutaneous metastasis of gastric adenocarcinoma. Two cycles of chemotherapy consisted of oral S-1 and intravenous cisplatin (SPIRITS regimen); this was markedly effective to reduce the primary gastric lesion and almost all the metastatic lesions.

Focal choroidal excavation complicated with choroidal neovascularization in young and middle aged patients

AIM: To investigate the clinical and optical coherence tomography(OCT) features of focal choroidal excavation(FCE) complicated with choroidal neovascularization(CNV) in young and middle aged patients. METHODS: We performed a retrospective review of 26 patients with FCE accompanied by CNV. All patients underwent a complete ophthalmic examination. We analyzed the clinical characteristics of patients, focusing on the spectral-domain OCT features. All patients received intravitreal injection of anti-vascular endothelial growth factor(anti-VEGF) agents. And we assessed the changes of central retinal thickness and best-corrected visual acuity(BCVA) after anti-VEGF therapy. RESULTS: The mean age of 26 patients was 35.5±7.3 y(range, 21-48 y). Of the 26 FCE lesions, 11 were located subfoveal, 6 were parafoveal, and 9 were extrafoveal. The mean FCE depth was 129.8±50.3 μm, and the mean width was 901.3±306.0 μm. The FCE depth was correlated positively with the width, but not correlated with age or refractive error. CNV was located within the excavation(19 eyes) or adjacent to the excavation(7 eyes). After anti-VEGF therapy, the central retinal thickness was significantly reduced and the BCVA was significantly improved. In the absorption process of subretinal fluid, we found that the fluid in the excavations needed to be absorbed at the last. A small amount of residual fluid could still be seen in a few deep excavations even after a longterm follow-up.CONCLUSION: FCE may be an important reason to cause CNV. Especially in young patients with idiopathic CNV, we should pay attention to the use of OCT to check the presence of FCE. Anti-VEGF therapy is generally effective for CNV associated with FCE.

Blockade of the Sonic Hedgehog Signalling Pathway Inhibits Choroidal Neovascularization in a Laser-induced Rat Model

Sonic hedgehog (Shh) signaling has recently been shown to be involved in the pathological angiogenesis in response to tissue hypoxia and ischemic injury.Hypoxia/ischemia is considered to play an important role in the development of choroidal neovascularization (CNV).This study was aimed to examine the effect of blockade of the Shh signaling pathway on CNV and the underlying mechanism.A total of 64 male Brown-Norway (BN) rats were used in this study.One eye of each rat underwent laser photocoagulation.The other eye served as normal control.After the laser treatment, the 64 rats were divided into four groups (n=16 in each group):Blank control group, in which no intravitreal administration was given; cyclopamine group, recombinant Shh N-terminals protein (rShh) group and phosphate-buffered saline (PBS) group, in which cyclopamine (a Shh inhibitor), rShh (a Shh activator) and PBS were intravitreally injected into the laser-treated eyes respectively every other day for a total of four intravitreal injections immediately after the laser treatment.Fourteen days after the intravitreal administration, the changes of CNV-related variables, including positive CNV lesion percentage, CNV membrane area and CNV membrane thickness, were evaluated by fluorescein anqiography, indocyanine green angiography and pathological examinations.The mRNA and protein expression of PTCH1, Gli1, HIF-1α, VEGF and DLL4 in each group on 14 days of CNV model was detected by real-time quantitative PCR and western blot analysis, and the relationship between the Shh cascade and the HIF-1α-VEGF-DLL4 cascade in CNV was analyzed.The results showed that the CNV membrane area and the CNV membrane thickness were decreased by 62.5% and 41.9% in the cyclopamine group and increased by 85.7% and 64.3% in the rShh group in comparison to those in the blank control group (P【0.01 for each).There was no significant difference in the CNV membrane area and thickness between the blank control group and PBS group (P=0.102 and P=0.063, respectively).Real-time quantitative PCR revealed a 5.23-, 4.14-, 2.97-, 2.78-and 2.39-fold up-regulation of the mRNA expression of PTCH1, Gli1, HIF-1α, VEGF and DLL4 genes in the laser-treated eyes compared with the normal control eyes in the control group.In the cyclopamine group, the mRNA and protein expression of Gli1, HIF-1α, VEGF and DLL4 was significantly down-regulated (P【0.05 for each) while the expression of PTCH1 showed no significant changes at the mRNA (P=0.293) and protein level (P=0.304).The mRNA expression and protein expression (P=0.001 and P=0.021, respectively) of PTCH1, Gli1, HIF-1α, VEGF and DLL4 was significantly increased in the rShh group when compared with the control group.The expression level of these genes was related to the severity of the CNV.It was concluded that intravitreal administration of cyclopamine can effectively inhibit the formation of laser-induced experimental CNV by down-regulating the expression of the HIF-1α-VEGF-DLL4 cascade in CNV.The Shh signaling pathway as an upstream signaling pathway of HIF-1α-VEGF-DLL4 cascade is implicated in the development of experimental CNV.

Long-term observation of vitrectomy without subretinal hemorrhage management for massive vitreous hemorrhage secondary to polypoidal choroidal vasculopathy

AIM: To describe the long-term observation of vitrectomy without subretinal hemorrhage(SRH) management for massive vitreous hemorrhage(VH) secondary to polypoidal choroidal vasculopathy(PCV). METHODS: This is a retrospective, consecutive case series. A total of 86 eyes of 86 patients with >14d of massive VH associated with PCV were included. All patients underwent vitrectomy without SRH management, followed by intravitreal ranibizumab injections and/or photodynamic therapy(PDT) as needed. The main outcome measures were best-corrected visual acuity(BCVA), postoperative adverse events and the recurrence of VH. RESULTS: The average follow-up period was 25.5±9.2 mo(range 12-35 mo). Mean BCVA at baseline(2.16±0.39 logM AR)had improved significantly, both 3 mo after surgery(1.42±0.66 log MAR, P<0.001) and by the last visit(1.23±0.74 logM AR, P<0.001). The common postoperative complications included macular subretinal fibrosis in 14 eyes(16.3%) and ciliary body detachment in 4 eyes(4.7%).Nineteen eyes(22.1%) received following treatment with ranibizumab injections without/with PDT, and 15(17.4%)were resolved. Four eyes(4.7%) had recurrent hemorrhage during the follow-up period. In multiple regression analysis,thicker SRH(beta=0.33, P=0.025) in the preoperative B-scan and the presence of foveal subretinal fibrosis(beta=0.28, P=0.018) in the follow up were associated with poor postoperative BCVA. CONCLUSION: Vitrectomy without SRH management for massive VH secondary to PCV improved/stabilized visual function in the long-term observation. Eyes presenting with thicker SRH preoperatively and forming foveal subretinal fibrosis in the follow-up period tended to have worse BCVA.

Comparison of choroidal thickness measured by two methods

AIM: To examine the profile of the choroidal thickness (CT) in healthy myopia subjects and emmetropic participants by Heidelberg Eye explore software and Image 3 software so as to compare the agreement and reproducibility of the two methods. METHODS: Thirty-six study participants (36 eyes) were enrolled in this research. The fovea and parafoveal region (the region of 6mm diameter of the fovea as center) of the images were selected by spectral domain optic coherence tomography (SD-OCT). The choroidal thickness was measured manually by the Heidelberg Eye explore software (version 5.3.3.0, Heidelberg Engineering) with a vertical line and the Image 3 software with a line vertical to the retinal pigment epithelial layer. The agreement and reproducibility of the two methods were described by the Bland-Altmann analysis. RESULTS: As compared with Heidelberg Eye explore software (39.9186), the repeatability coefficient is lower calculated by Image 3 software (27.3525). The Bland-Altmann analysis showed that the limits of 95% CI of agreement analysis is -18.437-63.949 mu m and the upper limits of the precision of the 95% CI of agreement is between 16.102 and 111.796 mu m and the lower limits is range from -66.29-21.41 mu m, which reflected a great variations of the difference. CONCLUSION: The repeatability and agreement of measurement implied by Image 3 software was better than the Heidelberg Eye explore software. The Image 3 software should be used for measuring the choroidal thickness in future study in China.

Inhibition of choroidal neovascularization by lentivirusmediated PEDF gene transfer in rats

AIM: To evaluate the effects of lentivirus-mediated pigment epithelium-derived factor (PEDF) gene transfer performed in treatment of rats with established choroidal neovascularization (CNV), and investigates the mechanism by which PEDF inhibits CNV in rats. METHODS: Brown Norway (BN) rats (n=204) were induced by exposure to a laser, and then randomly assigned to 3 groups: no treatment; treatments with intravitreal injection of lentivirus-PEDF-green fluorescent protein (GFP) or lentivirus-control GFP (free fluorescent protein). Following induction and treatment, the CNV tissue was assessed for form, size and vessel leakage by fluorescein fundus angiography (FFA), optical coherence tomography (OCT), histopathology, and examination of choroidal flat mounts. VEGF, Flk-1, and PEDF expression were evaluated by real-time polymerase chain reaction (PCR) and Western blot. RESULTS: A stable laser-induced rat model of CNV was successfully established, and used to demonstrate lentivirus-mediated REDO gene transfer by intravitreal injection. Expression of green fluorescence labelled PEDF was observed in the retina up to 28d after injection. An intravitreal injection of lentivirus-PEDF-GFP at 7d led to a significant reduction in the size, thickness and area of CNV showed by FFA, OCT and choroidal flat mounts. PEDF was up-regulated while VEGF and Flk-1 were down-regulated in the lentivirus-PEDF-GFP group. The differences in VEGF and Flk-1 expression in the control and lentivirus-PEDF groups at 7, 14, 21 and 28d after laser induction were all statistically significant. CONCLUSION: Lentivirus-mediated PEDF gene transfer is effective for use in treatment of laser-induced CNV, and PEDF exerts its therapeutic effects by inhibiting expression of VEGF and Flk-1.

Effects of two different doses of intravitreal bevacizumab on subfoveal choroidal thickness and retinal vessel diameter in branch retinal vein occlusion

AIM： To investigate the effects of two different doses of intravitreal bevacizumab on subfoveal choroidal thickness （SFChT） and retinal vessel diameter in patients with branch retinal vein occlusion. METHODS： An interventional, restrospective study of 41 eyes of 41 patients who had completed 12mo of follow-up, divided into group 1 （1.25 mg of bevacizumab, 21 eyes of 21 patients） and group 2 （2.5 mg of bevacizumab, 20 eyes of 21 patients）. Complete ophthalmic examination, fluorescein angiography, enhanced depth imaging optical coherence tomography and measurement of retinal vessel diameter with IVAN software were performed at baseline and follow-up. RESULTS： The SFChT changed from 279.1 （165-431） μm at baseline to 277.0 （149-413） μm at 12mo in group 1 （P= 0.086）, and from 301.4 （212-483） μm to 300.3 （199-514） μm in group 2 （P=0.076）. The central retinal arteriolar equivalent （CRAE） changed from 128.8 ±11.2 μm at baseline to 134.5±8.4 μm at 12mo in group 1, and from 134.6±9.0 μm to 131.4±12.7 μm in group 2 （P =0.767）. The central retinal venular equivalent （CRVE） changed from 204.1±24.4 μm at baseline to 196.3±28.2 μm at 12mo in group 1, and from 205.8±16.3 μm to 194.8±18.2 μm in group 2 （P=0.019）. The mean central macular thickness （P〈0.05） and average best-corrected visual acuity （BCVA; P〈0.05） improved in both groups CONCLUSION： Changes in the SFChT are not statistically significant and not different according to the doses of bevacizumab. The CRAE did not show significant change, however, the CRVE showed significant decrease regardless of the dose.