角膜接触镜相关细菌性角膜炎的研究进展

角膜接触镜(CL)现已成为常见的视力矫正手段之一,随着其材料与功能的不断开发,在全球有超过1.4亿的使用者且需求量逐年递增。配戴CL可导致如干眼、角膜擦伤、巨乳头性结膜炎在内的多种并发症,感染性角膜炎是其中最为严重的一种。研究发现CL相关感染性角膜炎的病原体主要以细菌为主,所占比例可达80%～95%,或与其菌体成分、毒力机制、生物膜形成等特点及镜片本身与使用过程易于引入病原并降低角膜及泪液的抗菌能力、造成眼表缺氧与眼表炎症有关。过夜配戴与长时间配戴镜片,不规范的镜片购买、使用及护理流程等也可成为细菌感染的危险因素。本文主要就CL相关细菌性角膜炎的发病机制、危险因素、诊断、治疗及预防相关研究进行综述。     

长期持续配戴软性角膜接触镜对角膜中央厚度的影响

目的 :探讨长期持续配戴软性角膜接触镜者与无角膜接触镜配戴史者中央角膜厚度的差异。方法 :应用超声角膜测厚仪检测无角膜接触镜配戴史者 10 0例 (198眼 )和长期持续配戴软性角膜接触镜者 4 0例 (77眼 )的中央角膜厚度。结果 :无角膜接触镜配戴史者中 ,高度近视眼组与中低度近视眼组的角膜中央厚度平均值 ,差异无统计学意义 (P>0 .0 5 )。长期持续配戴软性角膜接触镜者平均中央角膜厚度为 (0 .5 4 7± 0 .0 30 )mm ,无角膜接触镜配戴史者平均中央角膜厚度为 (0 .5 5 7± 0 .0 4 8)mm ,两组比较差异有显著性 (P <0 .0 5 )。结论 :长期持续配戴软性角膜接触镜者角膜中央厚度明显薄于无角膜接触镜配戴史者     

新型长戴型角膜接触镜的临床观察

目的 :观察新型长戴型角膜接触镜———PureVi sion(PV)的临床效果及其安全性。方法 :33例 (6 6眼 )隐形眼镜配戴者平均屈光度为 (- 4 .36± 1.5 4 )D ,配戴PureVision连续配戴型隐形眼镜 (简称PV) ,共连续配戴 1个月后更换镜片 ,观察时间为 2个月。配戴前检查视力、屈光度 ,裂隙灯检查眼前段 ,做镜片配适评估并行问卷调查做主观评价。结果 :眼前段检查显示 ,第 1个月连续配戴后 ,角膜缘充血、角膜新生血管、球结膜充血、巨乳头结膜炎、角膜荧光素染色等程度与配戴前相同的患者所占的比例 ,分别是 88.9%、96 .3%、6 4 .8%、5 0 %及 5 7.4 %。第 2个月连续配戴后 ,以上指标观察显示 ,与配戴前相同的患者比例分别是 95 .8%、87.5 %、85 .4、70 .8%及 5 6 .3%。配戴前患者均无角膜水肿 ,而连续配戴 1个月后角膜轻度水肿者占 14 .8% ,第二个月连续配戴则无角膜水肿发生。配戴者的主观评价显示 ,PV镜片的舒适度、清晰度以及镜片的整体满意度方面均高于以往配戴的镜片。结论 :新型长戴型角膜接触镜———PureVision的配戴者对该镜片的主观评价满意度较高 ,连续配戴后未见严重并发症的出现     

解读2017年版美国眼科临床指南(PPP):角膜接触镜的安全拓展应用

随着全球近视患病率的不断上升,角膜接触镜的应用越来越普及。角膜接触镜材料的改进为安全配戴创造了条件,但仍有一些配戴方式和护理方法会带来感染性角膜炎的隐患。近年来角膜接触镜最重要的拓展应用之一是青少年近视控制。本文结合眼科临床指南(PPP)与最新文献汇总一些常见误区,并推荐可有效延缓近视加深的角膜接触镜种类。     

长期配戴角膜接触镜角膜中央厚度的变化

目的探讨长期持续配戴软性角膜接触镜者和长期配戴硬性透氧性接触镜(rigidgas-permeablecontactlens,RGP)者与无角膜接触镜配戴史者中央角膜厚度的差异。方法应用超声角膜测厚仪检测无角膜接触镜配戴史者500例(918眼)、长期持续配戴软性角膜接触镜2年以上200例(386眼)和长期配戴RGP≥1年者100例(195眼)的中央角膜厚度。结果无角膜接触镜配戴史者,平均角膜中央厚度为(528.59±23.37)μm,长期持续配戴软性角膜接触镜者平均中央角膜厚度为(512.31±21.73)μm,配戴RGP者平均中央角膜厚度为(515.03±22.97)μm。配戴软性角膜接触镜者与正常者比较,差异有显著性(P<0.05)。配戴RGP者与正常者比较,差异有显著性(P<0.05),配戴软性角膜接触镜者与RGP者比较,差异无显著性(P>0.05)。结论长期持续配戴软性角膜接触镜者和RGP者平均中央角膜厚度均薄于无角膜接触镜配戴者。     

解读2017年版美国眼科临床指南(PPP):角膜接触镜的安全拓展应用

随着全球近视患病率的不断上升,角膜接触镜的应用越来越普及。角膜接触镜材料的改进为安全配戴创造了条件,但仍有一些配戴方式和护理方法会带来感染性角膜炎的隐患。近年来角膜接触镜最重要的拓展应用之一是青少年近视控制。本文结合眼科临床指南(PPP)与最新文献汇总一些常见误区,并推荐可有效延缓近视加深的角膜接触镜种类。     

日本角膜接触镜的历史、现状和展望

日本的角膜接触镜历史可以追溯到1951年，美尼康公司的创始人，现任主席田中恭一先生成功地研制出日本第一枚角膜接触镜，那是一种不透氧的硬性角膜接触镜。1960年，配戴舒适、具有亲水性和更好透氧性的软镜在捷克斯洛伐克出现了。而美尼康公司则继续致力于研究硬性高透氧角膜接触镜(RGP)，他们开发出含水量为72％的非离子软性角膜接触镜材料，同时他们研制了可以连续30d配戴的RGP镜片：美尼康Z，并最先获得获得美国FDA认证。目前，在日本配戴角膜接触镜的人群大约有一千五百万，其中硬镜配戴者与软镜配戴者的比例为4：6。在日本RGP的高配戴率是因为日本的眼科医生让配戴者充分相信RGP镜片的安全保证。1990年日本开始生产抛弃型角膜接触镜。角膜接触镜的抛弃和频繁更换概念改变了人们对角膜接触镜传统的认识，很快就被大众所接受。但是，原本被人们认为是一种医疗器具的角膜接触镜变成了人们熟知的日用品。这导致了配戴者的依从性下降，超时配戴，甚至角膜缺氧的现象日益增加。于是，研究人员开始开发高透氧的硅水凝胶(SH)材料。在欧洲和美国，硅水凝胶材料的角膜接触镜已被批准可以连续配戴30d。现在角膜接触镜的新功能体现在双焦点角膜接触镜和角膜屈光治疗镜(CRT)上，它们分别可以用于矫正老视和提高裸眼视力。中国的角膜接触镜配戴人群在很短的时间内就迅速增长到一千万人。     

配戴软性角膜接触镜对角膜中央厚度和曲率的影响研究

目的：探讨配戴软性角膜接触镜对角膜厚度、曲率的影响。 方法：检测143例(286只眼)配戴软性角膜接触镜患者的角膜中央厚度、角膜地形图。154例(308只眼)正常人为正常对照。比较连续配戴角膜接触镜不同年限患者和正常人的角膜厚度、角膜曲率的差异。 结果：配戴SCL较短者(≤2年)的CCT与对照组相比并没有明显的变化;但戴镜时间超过2年的II组和III组与对照组及配戴SCL≤2年的I组CCT相比时差异均有显著性(P<0.05);配戴SCL对角膜曲率无显著影响 结论：短期配戴SCL后角膜厚度尚无明显的变化,但随着戴镜时间的延长,角膜厚度逐渐变薄。而不论长期或者较短时间配戴SCL角膜曲率并无显著变化,但随着戴镜时间的延长角膜的不规则性有增加的趋势。     

长期配戴角膜接触镜对角膜厚度屈率及表面规则性的影响

目的 :了解长期配戴角膜接触镜对角膜厚度、屈率及表面规则性的影响。方法 :应用Orbscan角膜地形图系统检测 3 5例 (64只眼 )配戴角膜接触镜 5年以上患者的全角膜厚度、前表面角膜屈率及角膜前、后表面高度地形图。 2 0例 (4 0只眼 )正常人为正常对照。采用TMS 1角膜地形图系统的参数评价角膜表面规则性。比较正常人和配戴角膜接触镜 5年以上患者的全角膜厚度、角膜屈率、表面规则指数 (SRI)、表面不对称指数 (SAI)、预测视力(PVA)及角膜地形图图形的差异。结果 :戴镜组病例其配戴角膜接触镜的平均时间为 (13 45± 6 42 )年。与正常对照组相比 ,长期配戴角膜接触镜患者其角膜中央及周边 8个测量区的平均角膜厚度减少 3 0～ 5 0 μm (P <0 0 0 1) ,角膜屈率、最大角膜屈率 (MaxK )及最小角膜屈率 (MinK)明显增加 (P <0 0 1)。两组间角膜散光度无显著性差异。长期配戴角膜接触镜的患者其TSM 1系统参数中的SRI和SAI值较正常人明显增加 (P <0 0 1) ,PVA值无明显改变 (P =0 15 )。应用两种角膜地形图仪检查所得的角膜屈率地形图及角膜高度地形图的彩色编码图形类型 ,两组间无显著性差异。结论 :长期配戴角膜接触镜将导致全角膜厚度减小、角膜屈率增加及角膜表面不规则性增加     

氧气与角膜接触镜配戴

全球大约有八千万人 (约占总人口的 1.5 % )在配戴角膜接触镜 ,镜片的透氧性及配戴角膜接触镜后角膜的获氧状态是保证配戴安全性和有效性的关键。角膜需要多种营养物质以保证其正常的代谢功能 ,氧气是其中是重要的部分 ,只有在充分氧供的状态下 ,角膜才能保持稳定的 78%的水合状态 ,保证角膜透明性。为了进一步了解氧气与角膜接触镜配戴的关系 ,本文着重对角膜接触镜所致的角膜缺氧的主要表现及角膜接触镜的透氧性能及其表达指标作一综述。配戴角膜接触镜后 ,角膜的氧供明显减少 ,特别在闭眼状态下氧供减少尤其明显 ,角膜接触镜引起的角膜缺氧变化主要表现为 :①角膜上皮 :角膜上皮水肿 ,即因细胞间隙中水液充盈而发生的微囊样水肿 ,水肿明显时会影响视力并使角膜的敏感性下降 ;②角膜基质 :角膜基质水肿达 5 %以上即可从裂隙灯检查中发现 ,主要表现为条纹或皱褶 ,长期慢性水肿会诱发角膜新生血管的发生 ,逐步发生角膜疤痕、屈光改变等一系列问题 ;③角膜内皮 :慢性角膜缺氧最终会导致角膜内皮细胞形态的改变 ,而且无法代偿。保持角膜功能的最低需氧量称为“临界氧” ,理想的角膜接触镜应该是通过该镜片后到达角膜面的氧供超过临界氧。角膜接触镜的透氧性能表达指标主要有 :透氧性 (oxygenpermeability     

Comparative antiproliferative and cytotoxic profile of bevacizumab (Avastin), pegaptanib (Macugen) and ranibizumab (Lucentis) on different ocular cells

Aim To compare the antiproliferative and cytotoxic properties of bevacizumab (Avastin), pegaptanib (Macugen) and ranibizumab (Lucentis) on human retinal pigment epithelium (ARPE19) cells, rat retinal ganglion cells (RGC5) and pig choroidal endothelial cells (CEC). Methods Monolayer cultures of ARPE19, RGC5 and CEC were used. Bevacizumab (0.1–0.3 mg/ml), pegaptanib (0.025–0.08 mg/ml) or ranibizumab (0.04–0.125 mg/ml) diluted in culture medium were added to the cells. Expression of VEGF-receptors (VEGFR1 and VEGFR2) and von Willebrand factor (a marker for endothelial cells) were analysed by immunohistochemistry. CEC cells were stimulated with VEGF. Cellular proliferative activity was monitored by BrdU-incorporation into cellular DNA. For cytotoxicity assays cells were grown to confluence and then cultured in a serum-depleted medium to ensure a static milieu. MTT-test was performed after one day. Results CEC and ARPE19 cells stained positively for VEGFR1 and VEGFR2. More than 95% of the CEC cells were positive for von Willebrand factor. Ranibizumab reduced CEC cell proliferation by 44.1%, bevacizumab by 38.2% and pegaptanib by 35.1% when the drugs were used at their established clinical doses. The differences, however, between the three drugs in respect to cell growth inhibition were not statistically significant. Only a mild antiproliferative effect of bevacizumab or pegaptanib on ARPE19 cells could be observed. Ranibizumab did not alter ARPE19 cell proliferation. No cytotoxicity on RGC5, CEC and ARPE19 cells could be seen. Conclusions Bevacizumab, pegaptanib and ranibizumab significantly suppress choroidal endothelial cell proliferation. However, when used at the currently established doses none of the drugs was superior over the others in respect to endothelial cell growth inhibition. The biocompatibility of all three drugs — including the off-label bevacizumab — seems to be excellent when used at the currently recommended intravitreal dose. This work is presented on behalf of the Tuebingen Bevacizumab Study Group.     

Intravitreal use of bevacizumab (Avastin) for choroidal neovascularization due to ARMD: a preliminary multifocal-ERG and OCT study

Purpose To evaluate by MFERG and OCT the macular function before and after intravitreal use of bevacizumab (Avastin) in eyes suffering from CNV due to ARMD. Methods Eighteen eyes with subfoveal CNV due to ARMD were studied before and after intravitreal use of bevacizumab with MFERG and OCT. The post treatment follow up was three months. Results Before treatment, OCT shows an increase of the retinal thickening of the fovea and the electrical response densities in the fovea and parafovea were decreased in all patients. Three months after treatment, OCT showed a real resolution of the subretinal fluid. The electrical responses in the fovea and parafovea remained the same or slightly improved in some cases. The intraocular pressure remained normal and no inflammation was observed. Conclusion The intravitreal use of bevacizumab may provide anatomical correlates that support the concept of disease amelioration but the functional improvement of the macula three months after treatment is not obvious. However the method is promising and needs further evaluation.     

Distribution,markers, and functions of retinal microglia

Retinal microglia originate from hemopoietic cells and invade the retina from the retinal margin and the optic disc, most likely via the blood vessels of the ciliary body and iris, and the retinal vasculature, respectively. The microglial precursors that appear in the retina prior to vascularization are major histocompatibility complex (MHC) class I- and II-positive and express the CD 45 marker, but lack specific macrophage markers. They differentiate into ramified parenchymal microglia in the adult retina. A second category of microglial precursors, which do express specific macrophage markers, migrate into the retina along with vascular precursors. They appear around blood vessels in the adult retina and are similar to macrophages or cells of the mononuclear phagocyte series (MPS). Microglia are distributed in the outer plexiform layer (OPL), outer nuclear layer (ONL), inner plexiform layer (IPL), ganglion cell layer (GCL), and nerve fiber layer (NFL) of the primate retina. The pattern of microglial distribution in the avascular retina of the quail indicates that blood vessels are not responsible for the final location of microglia in the retina. In the human retina, microglia express MHC class I, MHC class II, CD 45 , CD68, and S22 markers. In the rat and mouse retina, OX 41 , OX 42 , OX 3 , OX6, OX18, ED1, Mac-1, F 4 /80, 5 D 4 anti-keratan sulfate, and lectins are used to recognize microglia. Microglial cells play an important role in host defense against invading microorganisms, immunoregulation, and tissue repair. During neurodegeneration, activated microglial cells participate in the phagocytosis of debris and facilitate regenerative processes. In autoimmune disease, microglia have dual functions: initiating uveoretinitis, but also limiting subsequent inflammation. Retinal microglia may be associated with vitreoretinopathy, diabetic retinopathy, glaucoma, and age-related macular degeneration. The goal of this article was to review the present knowledge about retinal microglia and the function of retinal microglia in pathological conditions.     

视网膜血管瘤增殖一年龄相关性黄斑变性的特殊类型

本文总结了年龄相关性黄斑变性的特殊类型—视网膜血管瘤增殖(RAP)的临床和造影表现及分期。RAP是起源于黄斑旁视网膜深层毛细血管的、以伴发多灶小片视网膜内出血及盘变前期即有视网膜-脉络膜血管吻合(RCA)形成为特征的新生血管性AMD。     

Long Noncoding RNA 3632454L22Rik Contributes to Corneal Epithelial Wound Healing by Sponging miR-181a-5p in Diabetic Mice

PurposeThis work explores the abnormal expression of long noncoding RNAs (lncRNAs), microRNAs (miRNAs) and messenger RNAs (mRNAs) in diabetic corneal epithelial cells (CECs) and constructs an associated competitive endogenous RNA (ceRNA) network. Moreover, we revealed that Rik may exert advantageous effects on diabetic corneal epithelial wound closure by sponging miR-181a-5p.MethodsWe obtained the profiles of differentially expressed lncRNAs (DELs) of CECs of type 1 diabetic versus control corneas by microarray and summarized the differentially expressed miRNAs (DEmiRs) and differentially expressed genes (DEGs) data by published literature. Subsequently, the ceRNA network was constructed using bioinformatics analyses. The levels of lncRNA ENSMUST00000153610/3632454L22Rik (Rik) and miR-181a-5p were verified. The localization of Rik was identified with fluorescence in situ hybridization (FISH), and dual-luciferase assays proved the targeted relationship between Rik and miR-181a-5p. Furthermore, we validated the functional impact of Rik in vitro.ResultsOverall, 111 upregulated and 117 downregulated DELs were detected in diabetic versus control CECs. The level of Rik located in both the cytoplasm and the nucleus was clearly downregulated, whereas miR-181a-5p was upregulated in vitro and in vivo in the diabetic group versus the control group. Rik can act as a ceRNA to bind to miR-181a-5p, thus promoting diabetic corneal epithelial wound healing in vitro.ConclusionsThis work investigated the expression profile of DELs and constructed ceRNA networks of diabetic CECs for the first time. Furthermore, we revealed that Rik may positively impact diabetic corneal epithelial wound healing by sponging miR-181a-5p, providing a novel potential therapeutic target of diabetic keratopathy (DK).     

近视及散光眼LASIK后非接触眼压计测量值的影响因素及其预测

目的 比较近视和(或)散光患者在LASIK手术前后非接触眼压计测量结果的差异及其影响因素,并得到预计眼压的计算公式.方法 对2005年12月至2006年11月在北京协和医院准分子激光手术中心行初次准分子激光原位角膜磨镶术(LASIK)矫正近视和(或)散光的患者进行回顾性研究,共93例(183只眼),采用非接触眼压计(NCT)测量术前和术后2周、1个月、3个月的眼压值,计算眼压变化值并分析其与各种变量之间的相关性,应用多元线性回归从相关变量得到术后预计的测量眼压值及眼压变化值.结果 患者术后3个月眼压较术前平均下降(5.74±2.03)mmHg,其变化与性别、年龄均不相关,但与术前屈光度有明显的关系.多元线性回归分析得到术后实际测量的眼压与术前眼压呈正性相关,而与手术切削量呈负相关(R2=0.442,P<0.001),术后预计测量眼压=5.175+0.411×术前眼压-0.0205×切削量,手术后眼压测量下降值0.589×术前眼压+0.0205×切削量-5.175.结论 通过术后实际测量眼压值与预测值比较,可以及时发现高眼压的患者,避免低估眼压以致漏诊青光眼而造成患者视功能损失.虽然可以通过预测公式来判断实际测量眼压值是否在正常范围.但更有效的方法是使用不受角膜变化影响的眼压计测定眼压.     

Assessing hydroxychloroquine toxicity by the multifocal ERG

Twenty patients on Plaquenil treatment were evaluated for retinal toxicity using the (EOG) and the mfERG. Group 1 comprises 15 patients (30 eyes) with normal EOG. From these patients 11 (22 eyes) showed normal RRD of mfERG in area 1 and area 2. The rest four patients (8 eyes) the RRD were reduced. Six months after interruption of HC, the mfERG improved in three cases. Group 2 comprises 5 patients (10 eyes) with subnormal EOG. Four (8 eyes) of these showed a decrease of RRD of the mfERG in area 1 and 2. In the rest one (2 eyes) the RRD were normal. Six months after interruption of HC the mfERG and the EOG improved in 2 cases. These results postulate that the mfERG may be used as an alternative method, perhaps more sensitive, for the detection of the HC retinopathy and the follow up of the patients on hydroxychloroquine.     

糖尿病患者的视网膜电图分析

目的分析糖尿病(DR)患者视网膜电图(F-ERG)的振幅、峰潜时、OPS总和振幅及其与病程的相关性.方法将53例102眼糖尿病患者分为三组(NDR、BDR、PDR),并采用美国UATA-2000型视觉电生理仪对53DR例进行F-ERG检查,主要分析其a、b波峰潜时、振幅、OPS总和振幅.结果随着DR病情的加重,ERG及OPS无波的情况所占比例增大.a波峰潜时BDR组和正常组比较差异有极显著性(P<0.01),BDR组和DM无DR组比较差异有显著性(P[WTBZ〗<0.05);a波振幅正常对照组与其他各组比较差异均有极显著性(P<0.01).b波振幅正常对照组与BDR、PDR间以及DM无DR组与BDR、PDR组间均有极显著性差异(P<0.01).OPS总和振幅除了BDR与PDR间外,其他各组比较差异均有极显著性(P<0.01).结论OPS、ERG之a、b波振幅,尤其是b波振幅,可以作为早期诊断DR患者以及估计预后的敏感指标;良好的血糖控制,可以延缓DM的病情发展.     

Practical astigmatism analysis for refractive outcomes in cataract and refractive surgery

The fundamental concepts underpinning the vectorial analysis of astigmatism are straightforward and intuitive, easily understood by employing a simple golf-putting analogy. The Alpins methodology utilizes three principal vectors and the various ratios between them to provide an aggregate analysis for astigmatic change with parallel indices for spherical correction. A comparative analysis employing both arithmetic and vectorial means together with necessary nomogram adjustments for refining both spherical and astigmatic treatments can also be derived. These advanced techniques, together with their suitability for statistical analysis, comprehensively address the outcome analysis requirements of the entire cornea and the eye's refractive correction, for the purpose of examining success in cataract and refractive surgery.