抗血管内皮生长因子小干扰RNA抑制大鼠角膜新生血管形成的研究

目的 探讨抗血管内皮生长因子小干扰RNA(VEGF-siRNA)对角膜碱烧伤急性期新生血管(CNV)形成的抑制作用.方法 实验研究.体外化学合成VEGF序列特异性双链小干扰RNA(VEGF-siRNA),脂质体介导转染体外培养的大鼠角膜上皮和基质细胞,实时PCR法检测转染后各时段VEGF mRNA表达水平,酶联免疫吸附实验测定转染后各时段VEGF蛋白表达水平.制作大鼠角膜碱烧伤动物模型,采用VEGF-siRNA转染的角膜上皮移植联合前房注射脂质体包裹的VEGF-siRNA治疗急性期CNV,免疫组化和ELISA分别检测角膜VEGF表达,观察术后CNV形成.细胞实验和动物实验中siRNA处理组和对照组VEGF蛋白含量比较,采用两样本均数比较的t检验.结果 siRNA对角膜上皮细胞VEGFmRNA的抑制效率达60%～84%,角膜基质细胞VEGFmRNA的抑制效率达59%～76%,角膜上皮和基质细胞VEGF蛋白表达也有相应的下降.采用VEGF-siRNA转染的角膜上皮移植联合前房注射VEGF-siRNA治疗,实验组CNV面积显著小于对照组;实验组VEGF表达水平显著低于对照组.结论 VEGF-siRNA能显著抑制大鼠角膜碱烧伤急性期CNV形成.     

新鲜羊膜移植术对角膜新生血管抑制作用的实验研究

目的探讨新鲜羊膜移植术对角膜碱烧伤后角膜新生血管和上皮愈合作用的影响,并与保存羊膜作比较.方法用48只新西兰大白兔制作角膜碱烧伤模型,烧伤后48h设立新鲜羊膜移植组(fAMT)、保存羊膜移植组(pAMT)和对照组(C).术后每日观察角膜新生血管和上皮愈合情况.并于术后14、30d以计算机图像分析系统定量测定新生血管和上皮愈合面积.结果术后30dfAMT组、pAMT组、C组角膜新生血管面积分别为87.87mm2±3.57mm2、96.66mm2±12.00mm2、105.13mm2±6.70mm2.统计分析显示,fAMT组角膜新生血管面积小于pAMT组(P＜0.05),上述2组均小于C组(P＜0.05).结论新鲜羊膜移植术可抑制碱烧伤后角膜新生血管生长,其作用优于保存羊膜移植术.     

瘦素和血管内皮生长因子在碱烧伤诱导的大鼠角膜新生血管模型中的表达

目的 观察碱烧伤后不同时期角膜的组织病理学变化,以及瘦素和血管内皮生长因子(vascular endothelial growth factor,VFGF)的表达,探讨它们与角膜新生血管(corneal neovascularization,CNV)的关系.方法 使用碱烧伤诱导大鼠角膜新生血管模型,采用浸润1 mol·L-1 NaOH溶液、直径为3 mm的单片滤纸,准确置于大鼠右眼角膜中央30 s,制作CNV模型.25只SD大鼠右眼为实验眼,随机分成5组,每组5眼,左眼为正常对照眼.每天用裂隙灯显微镜观察角膜新生血管,分别计算新生血管长度和面积.并行HE染色和免疫组织化学检测.结果 碱烧伤后4 d、7 d、14 d、21 d,实验组CNV面积分别为:(2.55±0.15)m2、(4.15±0.36)mm2、(10.21±0.45)mm2、(8.56±0.06)mm2.免疫组织化学检测显示角膜碱烧伤后1 d,实验组瘦素、VEGF的表达开始增高,碱烧伤后14 d达高峰,14 d后瘦素、VEGF的表达下降,21 d后显著下降;其表达部位主要分布在形成的新生血管区域和上皮层;正常对照组瘦素可微弱表达于角膜上皮层和基质层,VEGF没有表达或仅在上皮基底膜有微弱表达.实验组角膜瘦素、VEGF阳性表达率较对照组明显增加(χ2=29.07,P=0.001;χ2=35.51,P=0.001),瘦素与VEGF的表达具有正相关性(r=0.95,P=0.001).结论 瘦素和VEGF表达水平与角膜新生血管的生成具有相关性,瘦素可能成为治疗CNV的靶点.     

新鲜羊膜移植术治疗早期碱烧伤对角膜新生血管和上皮愈合的影响

探讨新鲜羊膜移植术在早期角膜碱烧伤治疗中对角膜新生血管和上皮愈合作用的影响 ,并与保存羊膜作比较。方法 :以 48只新西兰大白兔制作角膜碱烧伤模型 ,烧伤后 48小时设立新鲜羊膜移植组、保存羊膜移植组和对照组。术后每日观察角膜新生血管和上皮愈合情况。并于术后 14天、 30天以计算机图像分析系统定量测定新生血管和上皮愈合面积。结果 :新鲜羊膜移植组角膜新生血管面积小于保存羊膜移植组 ,两者均小于对照组 (P <0 0 1)。术后 14天新鲜羊膜移植组角膜上皮愈合面积较保存羊膜移植组大 ,两者均较对照组愈合快 (P <0 0 1)。结论 :在角膜碱烧伤早期治疗中 ,新鲜羊膜移植可抑制角膜新生血管和促进角膜上皮愈合 ,其效果优于保存羊膜移植。     

VEGF和PEDF在实验性大鼠角膜新生血管组织中的动态表达

目的探讨血管内皮生长因子(vascularendothelialgrowthfactor,VEGF)和色素上皮衍生因子(pigmentepitheliumderivedfactor,PEDF)在实验性大鼠角膜新生血管(cornealneovascularization,CNV)形成过程中的动态表达及作用。方法诱导大鼠角膜碱烧伤模型,免疫组化法检测烧伤后1d、3d、5d、7d、10d、14d角膜VEGF及PEDF免疫反应;图像分析系统测定其蛋白表达。结果在CNV组织中,VEGF阳性表达于3~7d最明显,14d后表达微弱;PEDF在7~10d时表达最强烈,14d时明显下降。2种因子动态表达与CNV发展存在一定时间相关性。结论VEGF与PEDF在缺血缺氧诱导的大鼠CNV的形成过程中均有显著表达,且其动态过程与CNV的发展进程一致,二者表达失衡可能参与CNV形成及发展过程的调控。     

大鼠角膜碱烧伤后ILK和VEGF的表达与角膜新生血管的相关性研究

目的:研究大鼠角膜碱烧伤后整合素连接激酶(ILK)、血管内皮生长因子(VEGF)的表达及其与角膜新生血管(CNV)的相关性.方法:通过碱烧伤Sprague-Dawley(SD)大鼠角膜制备角膜新生血管动物模型,采用形态学方法观察碱烧伤后新生血管的生成,免疫组织化学方法检测ILK及VEGF在碱烧伤后不同时间点的表达情况.结果:ILK及VEGF在正常大鼠角膜上皮中仅有微弱表达,而在碱烧伤后各时间点的角膜上皮以及血管内皮中均有明显表达(P<0.01).碱烧伤后3~5d,可见二者阳性表达,且迅速增加;7~10d,二者表达达到高峰;14d以后二者表达逐渐减弱,与形态学观察CNV生长过程一致.即碱烧伤后3~5d新生血管生长迅速,7~10d生长达到高峰,14d以后血管开始逐渐减少退化.ILK及VEGF表达的变化均与CNV的变化呈正相关(ILK与CNV面积相关系数r=0.900,P<0.01;VEGF与CNV面积相关系数r=0.878,P<0.01),且二者之间也存在正相关性(r=0.926,P<0.01).结论:大鼠角膜碱烧伤后ILK及VEGF均有明显表达,二者作为重要的调控子共同参与了CNV的形成过程.     

大鼠角膜碱烧伤后新生血管基因治疗作用的研究

目的观察白细胞介素-1受体拮抗剂(IL-1ra)基因对大鼠角膜碱烧伤后新生血管(CNV)的治疗作用.方法建立角膜碱烧伤后CNV模型,以pcDI质粒作为IL-1ra基因的表达载体,通过结膜下注射进行基因治疗.Wistar 大鼠随机分为5组,其中3组为不同剂量基因质粒治疗组,以及地塞米松组和生理盐水对照组.利用裂隙灯显微镜观察和角膜灌注铺片法观察记录(CNV)的生长情况;利用半定量逆转录聚合酶链式反应(RT-PCR)检测角膜内血管内皮生长因子(VEGF)mRNA的表达.结果基因质粒治疗组和激素组CNV的生长均受到明显抑制.与阴性对照组相比,在烧伤后第7、14、28天,50 μg质粒基因治疗组CNV面积抑制率分别为34.7%、37.5%、43.7%,差异有显著性(P<0.01),而不同剂量基因治疗组间差异无显著性(P＞0.05).烧伤后24 h,VEGF mRNA水平上升至高峰,为正常角膜的5.30倍;第4天为正常角膜的2倍;第7天恢复至正常.50 μg质粒基因治疗组VEGF mRNA的表达水平受到明显抑制,24 h时下降了48.7%(P<0.01);烧伤后4天,下降了27.2%(P<0.01).结论 pcDI-hIL-1ra基因质粒对CNV具有抑制作用,其机制与抑制VEGF mRNA的上调有关.     

血管内皮生长因子与角膜碱烧伤后血管新生

目的　探讨血管内皮生长因子(VEGF)在大鼠角膜碱烧伤后角膜新生血管形成中的作用。方法　利用氢氧化钠烧灼大鼠角膜表面,建立大鼠角膜新生血管(CNV)模型,每日裂隙灯下观察角膜新生血管的发展,并分别于烧伤后1、4、7、14、2 1d处死大鼠,摘除角膜作病理切片,多形核白细胞(PMN)计数;免疫组化法检测VEGF的表达;图像分析系统测定该因子的蛋白表达。结果　光镜下显示正常组PMN记数为0 . 5 0 0±0 . 62 9,烧伤后1d角膜缘处的PMN开始增多,7d时增加最明显,此后逐渐减少;免疫组化显示:VEGF在CNV中阳性表达逐渐增加,于7d组表达最明显,2 1d后几乎无表达;图像分析与免疫组化结果一致。结论　碱烧伤后CNV形成中,VEGF的表达增加,并与角膜的炎性反应程度平行,PMN浸润可能是CNV形成的关键因素。     

色素上皮衍生因子抑制碱烧伤角膜新生血管的机制研究

目的:探讨外源性色素上皮衍生因子(pigment epitheliumderived factor,PEDF)抑制大鼠角膜新生血管(corneal neovascularization,CNV)形成的作用机制,检测外源性PEDF对CNV模型中内源性血管内皮生长因子(vascularendothelial growth factor,VEGF)及PEDF、细胞凋亡受体/配体(Fas/FasL)表达的影响,以及对CNV内皮细胞凋亡的影响(脱氧核糖核苷酸末端转移酶介导的缺口末端标记法——TUNEL法测定)。方法:大鼠随机分为3组:PEDF治疗组(A组)、生理盐水对照组(B组)、正常组(C组)。建立碱烧伤诱导的大鼠CNV模型,A组和B组分别给予PEDF+氯霉素滴眼液和生理盐水+氯霉素滴眼液点眼,采用裂隙灯观察CNV的生长情况,用免疫组化方法检测并半定量分析VEGF,PEDF,Fas及FasL在正常角膜组织和碱烧伤后4,7,10,14d角膜组织中的表达,用TUNEL法检测CNV内皮细胞的凋亡情况。结果:正常角膜组织中可以检测到高PEDF表达和低VEGF表达,也可以检测到一定的低Fas和FasL表达。各时间点角膜新生血管的面积,A组均低于B组(P<0.05)免疫组化显示,碱烧伤后4,7,10,14d A组VEGF的表达均低于B组(P<0.05),PEDF的表达均高于B组(P<0.05),A组Fas/FasL的表达明显高于B组(P<0.05),A组TUNEL法测到的角膜新生血管内皮细胞凋亡计数和凋亡指数AI明显高于对照组(P<0.05)。两组检测到的VEGF均在第7d达到峰值,随后下降;而PEDF和Fas及FasL在第10d达到峰值,随后下降。碱烧伤后第4～10dVEGF/PEDF>1,CNV逐渐生长并达到峰值;第10d后VEGF/PEDF<1,CNV开始逐渐退化。结论:PEDF抑制碱烧伤后CNV的作用机制可以归结为两点:(1)下调VEGF的表达,控制PEDF/VEGF的动态比值,抑制CNV生长;(2)上调Fas/FasL等凋亡受体的表达,诱导角膜新生血管内皮细胞的凋亡,促进CNV的退化。     

兔角膜及房水中VEGF的表达与角膜新生血管形成的相关性

目的:探讨兔角膜与房水中VEGF的表达与角膜新生血管(corneal neovasucularization,CNV)形成的相关性。方法:兔33只,随机分为正常对照组、实验组和实验对照组,角膜缝线制备CNV模型,实验对照组自术后当日起隔日结膜下注射一定剂量地塞米松治疗。术后每日观察CNV生长情况并计算其面积。分别于术后1,4,7,14,21d检测角膜组织及房水中VEGF的表达情况。结果:实验对照组CNV生长情况及角膜组织炎症细胞浸润程度较实验组明显受到抑制(P<0.05)。角膜组织中VEGF主要定位于上皮细胞、基质纤维细胞、内皮细胞、浸润的炎症细胞及新生血管内皮细胞胞质中。实验组角膜组织内VEGF表达的阳性率随时间推移逐渐增高,且表达强度与CNV面积具有显著的相关性。角膜缝线后14,21d实验组VEGF表达阳性率显著高于实验对照组(P<0.05)。实验组房水中VEGF的含量随着时间的推移逐渐增长,各检测点均高于实验对照组,并且房水及角膜组织中VEGF的表达与CNV面积显著正相关。结论:CNV的形成与炎症细胞浸润密切相关,角膜及房水中的VEGF可能在CNV形成过程中发挥着重要的调控作用。地塞米松可能通过抑制炎症反应、下调VEGF等细胞因子的表达,进而抑制CNV的生长。     

Relationship Between Corneal Hysteresis and Corneal Resistance Factor with Other Ocular Parameters

Abstract

Purpose: To evaluate the relationship between corneal hysteresis (CH) and corneal resistance factor (CRF) with age, central corneal thickness (CCT), corneal curvature (KM), corneal volume (CV), and refractive error in naïve eyes. Methods: 105 healthy subjects (58 male and 47 female) were included in this study. The ages ranged from 19 to 82 years (mean 43.1?±?15.4 years) and refraction between ?11?D and +6?D (mean ?0.79?±?2.95?D). CH and CRF obtained with the Ocular Response Analyzer (ORA) were correlated with age, refractive error, Goldmann Applanation Tonometry (GAT), and with CCT, KM, CV obtained with the Pentacam, and with Corneal-Compensated Intraocular Pressure (IOPcc) and Goldmann-correlated intraocular pressure measurement (IOPg) obtained with ORA. A multivariable mixed effect model was used to evaluate associations among these parameters. Results: CH ranged from 6.9 to 14.6?mmHg (mean 10.26?±?1.49?mmHg); CRF ranged from 5.8 to 17?mmHg (mean 10.38?±?1.64?mmHg). Multivariate analysis showed a statistically significant correlation between CH with CCT (p?<?0.001), and KM (p?<?0.001), and between CRF with CCT (p?<?0.001) and GAT (p?<?0.001). Conclusions: Our findings support the hypothesis that CH and CRF are related to the corneal shape and thickness, and show a decrease of CH with age.     

A case of congenital corneal anesthesia with hypopyon in china

 PURPOSE: To report a case of congenital corneal anesthesia (CCA) associated with hypopyon and tactile hypoesthesia. METHODS: Case report. RESULTS: A 3-year-old girl presented with redness and mild photophobia in the left eye accompanied by corneal ulcer, hypopyon, and corneal neovascularization. Corneal sensation was reduced bilaterally. She exhibited an absence of normal response to painful stimuli. She also had extensive ulceration of the lateral borders and tip of the tongue. The left corneal biopsy revealed negative cultures for bacteria and fungi. She was treated with human amniotic membrane transplantation in the left eye. The response to treatment was good. CONCLUSION: This is the first case of CCA reported in China. CCA is often misdiagnosed as infectious keratitis. Amniotic membrane transplantation is effective in repairing the severe corneal ulcer which may be associated with CCA.     

Biomechanics and structure of the cornea: implications and association with corneal disorders

Recent studies have shown that alterations in corneal biomechanical properties are associated with corneal pathologies, particularly corneal ectasia. Moreover, these alterations may have implications with regard to the outcomes of therapeutic modalities and corneal refractive surgeries. We address corneal anatomy and its relevance to corneal biomechanical characteristics, as well as ocular and systemic conditions associated with changes in corneal biomechanics.     

A new multiple noncontinuous puncture (pointage) technique for corneal tattooing

AIM:To assess the safety and cosmetic efficacy of a new multiple noncontinuous transepithelial puncture technique for tattooing a decompensated cornea.METHODS:It was anon-comparative clinical case series study.The study examines 33 eyes in 33 patients with total corneal opacity due to corneal decompensation, which developed following intraocular surgery.Corneal tattooing was performed using the multiple noncontinuous transepithelial puncture technique (i.e. pointage). The safety of this new surgical strategy was assessed by occurrence of adverse events for the follow-up period. The cosmetic efficacy was determined by the patient’s cosmetic satisfaction and independent observer’s opinion about patient appearance.RESULTS:Seven women and 26 men were included in the study. The mean age was 46.4±17.5y (range:7-67). In total, 30 of 33 patients (91%) reported cosmetic satisfaction within the follow-up period. Only 3 patients (9%) required additional tattooing due to cosmetic unsatisfaction. Cosmetic outcomes were analyzed and classified as excellent or good in 13 (39%) and 17 (52%) patients, respectively. No serious adverse events developed, except delayed epithelial healing in 3 cases.CONCLUSION:The cosmetic outcomes of the multiple noncontinuous transepithelial puncture technique for corneal tattooing were good. The safety of this method is higher than conventional procedures. This new procedure also provides improved cost-effectiveness and safety over current corneal tattooing techniques.     

角膜基质透镜在角膜溃疡或穿孔修复中的应用

目的：研究由全飞秒激光SMILE手术所得的角膜基质透镜作为角膜移植材料治疗角膜溃疡的临床疗效。

方法：回顾性病例研究。收集本院2017-01/06角膜溃疡患者6例6眼,其中细菌性、真菌性、深层异物伴感染各1例1眼,角膜穿孔3例3眼。采用由全飞秒激光SMILE手术所得的角膜基质透镜作为角膜移植的材料进行修复手术,确保植片与角膜层间无空气间隙。术后随访1～6(平均3.71±1.56)mo,观察手术前后视力、角膜移植物存活情况及术后并发症发生情况等。

结果：所有患者均在控制感染下顺利完成手术,无术中并发症。术后所有角膜植片透明。末次随访时,患者最佳矫正视力(best corrected visual acuity,BCVA)较术前明显改善(0.48±0.12 vs 1.50±0.08),差异具有统计学意义(P<0.01)。

结论：来源于全飞秒激光屈光手术的角膜基质透镜用于角膜溃疡修复是安全有效的,但植片的远期疗效尚需进一步观察。     

Anterior amorphous corneal opacity and corneal thinning

PurposeTo present the clinical features of four cases with bilateral anterior amorphous corneal opacity.MethodsA retrospective study in four patients with bilateral anterior amorphous corneal opacity was conducted. Examinations included visual acuity, keratometry, slit-lamp biomicroscopy, confocal microscopy, anterior segment optical coherence topography, and histology.ResultsThree female and one male patients (mean age, 52.3 ± 8.9 years) showed bilaterally oval, amorphous sheetlike corneal opacities with central depression and thinning. Superior limbal opacities were observed in two of these patients. The best-corrected visual acuity ranged from 20/50 to 20/400, and the mean of the keratometry was 39.81 ± 3.97 D (diopters). They had mild dry eyes. The anterior segment optical coherence topography demonstrated hyporeflective abnormalities in the anterior depressed stroma in these four patients. Confocal microscopy revealed large round cells at the epithelial layer in one patient, and amorphous opacities with some strand-shaped opacities in the anterior stroma in all four patients. The mean of the corneal endothelial cells density in the eight eyes was 1521 ± 402 cells/mm². Central corneal stromalysis occurred in three patients, and descemetocele developed in two eyes. One patient received penetrating keratoplasty and two underwent lamellar keratoplasty. The histology of the corneal specimen revealed edematous basal epithelial cells, focal collagen disorganization in the thin stroma, and wartlike excrescences in a thickened Descemet's membrane.ConclusionAnterior amorphous corneal opacity is a rare keratopathy and may be one kind of rare corneal degeneration or dystrophy. Corneal stromalysis may occur in hyporefrective amorphous opacities and progress to descemetocele.     

过夜配戴角膜矫形镜(OK镜)后角膜曲率及厚度变化

目的了解过夜配戴角膜矫形镜(OK镜)后早期角膜曲率、角膜厚度及屈光度的变化.方法14个中低度近视患者(平均屈光度-3.89±1.26D)25眼,随机分成2组分别配戴Dk值不同的角膜矫形镜BE角膜矫形镜组(7人12眼,Dk≈140);E&E角膜矫形镜组(7人13眼,Dk＝58).采用夜戴方式,平均配戴时间10.76±1.27小时.用Orbscan角膜地形图系统检查配戴1晚后角膜曲率、角膜厚度的改变.同时记录裸眼视力及屈光度的改变.结果配戴1晚后所有患者的中央及周边的角膜均增厚(P＜0.05).Orbscan角膜地形图SimK值在垂直轴及水平轴均变平(垂直轴△SimK0.94±0.56D,P＜0.001;水平轴△SimK0.996=0.68D,P＜0.001).裸眼视力平均提高0.4±0.24(P＜0.001).屈光度平均减少-1.85±0.82D(P＜0.001).Dk值不同的2组之间中央及颞上方位点角膜增厚程度的差别有统计学意义.结论过夜配戴角膜矫形镜后减低近视屈光度的效果明显.初次过夜配戴角膜矫形镜可导致角膜厚度轻度增加.     

美容性角膜覆盖术疗效观察

目的:评价美容性角膜覆盖术治疗角膜(角巩膜)葡萄肿的临床效果。方法:对22例角膜(角巩膜)葡萄肿患者进行了美容性角膜覆盖术治疗。术后对所有病例的临床效果进行了随访观察。结果:22例均治愈,残留部分视力的2例的视力术后有所改善(2例2眼从术前手动/眼前到术后指数/眼前)。22例无1例发生排斥,角膜覆盖片的颜色除第1例因缺乏经验术眼的颜色明显深于对侧正常或正常人群眼的颜色外,其它无1例褪色。结论:应用角膜覆盖术治疗角膜(角巩膜)葡萄肿22例(22眼)临床证明疗效确实、安全可靠。     

Influence of corneal astigmatism, corneal curvature and meridional differences on corneal hysteresis and corneal resistance factor

Background: This study investigated the influence of corneal astigmatism, corneal curvature and meridional differences on corneal hysteresis (CH) and the corneal resistance factor (CRF) in a group of normal Chinese persons. Methods: Ninety‐five participants were recruited and data from the eye with higher corneal astigmatism were analysed. The anterior corneal curvature was measured by corneal topography. The Goldmann‐correlated intraocular pressure (IOPg), corneal‐compensated intraocular pressure (IOPcc), CH and CRF at different meridians (default horizontal position, 10°, 20° and 30° along the superotemporal and inferonasal meridians) were obtained from an ocular response analyser. The corneal powers at these specific meridians also were calculated. Results: At the default position, the IOPg and CRF had weak correlations with corneal astigmatism, while the IOPcc and CH were not significantly correlated with corneal astigmatism. Both the IOPg and IOPcc were measured significantly higher at the default position. The CH and CRF were lower at the default position but the difference in the CRF from obliquity could not reach statistical significance. The CH was not significantly correlated with the corneal power at all meridians. The CRF correlated with the corneal power only at 30° superotemporal. Conclusion: Corneal astigmatism and head tilt did not have much effect on the measurement of CH and the CRF, both of which were lowest along the horizontal meridian. Clinically, the difference was small. The influence of corneal power on CH and the CRF was minimal.