角膜内皮功能紊乱的易患因素

角膜内皮细胞密度是临床医师评估角膜内皮功能最常用的项目,但角膜内皮功能紊乱却没有得到相应的重视.近年来对各种眼部原发疾病、角膜移植术后等所致角膜内皮功能紊乱的临床数据有了更翔实的更新.眼部原发病中,各种类型的青光眼对角膜内皮的影响不尽相同,其中急性闭角型青光眼对角膜的损伤程度较慢性闭角型青光眼及开角型青光眼严重,青光眼不同的治疗方案对内皮的影响也各有特点.葡萄膜炎患者角膜内皮损伤的严重程度与炎症复发频数、炎症反应程度及病程密切相关.剥脱综合征患者前房含氧量低、细胞外纤维物质在眼前段的堆积、细胞发生纤维化改变等因素均可降低角膜内皮的功能,导致剥脱综合征患者角膜内皮细胞对损伤的耐受性差.对于角膜移植术后的患者,角膜移植排斥反应、手术方式、原发病、继发性晚期角膜内皮衰竭是角膜移植术后患者角膜内皮功能紊乱的重要因素.糖尿病是引起角膜内皮细胞储备能力下降的常见的全身性疾病,糖尿病患者细胞膜Na+/K+-ATP酶泵的功能降低、大量的晚期糖基化终产物的生成、代谢应激作用增强等因素均可降低角膜内皮创伤修复及愈合能力.本文就角膜内皮功能紊乱的易患因素进行综述,以帮助临床医师理解及重视该因素在内眼手术前的评估.     

闭角青光眼术后角膜厚度变化

各种类型青光眼均可造成角膜内皮密度降低而增厚,但术后短期难以直接观察角膜内皮状态。角膜厚度的变化可以反映角膜内皮细胞功能状态及损伤情况,在无明显上皮水肿的情况下,内皮功能亦可由角膜厚度判定。本文观察了青光眼术前及术后角膜厚度,采用直线回归方法计算角膜减薄速率,探讨青光眼及其手术对角膜厚度的影响。     

青光眼对角膜内皮细胞影响的现况研究

角膜的高度透明是实现视觉器官正常生理功能的重要条件之一，而解剖形态完整和生理功能正常的角膜内皮层则是保持角膜透明的关键。青光眼作为临床重要的致盲眼病，其对角膜内皮细胞的影响近年来越来越受到重视。为更深入认识高眼压状态下角膜内皮细胞形态、结构、功能的变化及机制，以及不同类型青光眼角膜内皮细胞变化的异同，现就青光眼高眼压对角膜内皮的影响作一综述，以期对青光眼患者的诊治及预后评价提供依据。     

大泡性角膜病变四例报告

大泡性角膜病变四例报告吉芳吴世信（上海长宁区中心医院眼科，２０００５１）角膜的透明性对维持有用的视力是至关重要的。角膜内皮和上皮的功能正常与否，直接影响角膜的透明度。眼外伤、内眼手术、眼内炎症、晚期青光眼、角膜激光治疗等均可因损伤角膜内皮和上皮功能而...     

角膜内皮衰竭患者行穿透性角膜移植术后的眼压变化及处理

角膜内皮衰竭或称角膜内皮功能失代偿一般是由眼外伤或眼内手术的创伤引起,如抗青光眼、白内障摘除和人工晶体植入等。近年来随着人工晶体植入术的开展,角膜内皮衰竭的患者也日渐增多。手术的创伤使角膜内皮细胞大量丢失,失去了正常的泵功能,角膜呈现持续性水肿和上皮大泡。解除角膜水肿的唯一办法是做8mm以上穿透性     

中央角膜厚度对压平眼压计测量值的影响

目的采用非接触式角膜内皮镜测量高眼压症与临床常见类型青光眼患者的中央角膜厚度central corneal thickness(CCT),并与正常人CCT平均值比较,探讨CCT对青光眼诊断、分类与治疗的指导意义.方法采用KONAN非接触式角膜内皮镜测量中央角膜厚度,Goldmann压平眼压计测量眼内压(IOP).将39例52眼原发性开角型青光眼(POAG),32例45眼慢性闭角型青光眼(CACG),18例29眼高眼压症眼(OHT),15例24眼正常眼压性青光眼(NTG),34例66眼可疑开角型青光眼(GS)的CCT和IOP值与173例322眼正常眼进行比较研究.所有资料输入计算机后在Windows操作环境下使用SPSS10.0统计软件进行统计分析.结果平均CCT值比较高眼压症(OHT)眼(600.21±24.20μm)＞POAG眼(574.37±31.92μm)＞正常对照眼(554.78±32.61μm)＞NTG眼(528.43±36.40μm).OHT、NTG、POAG眼与正常眼的CCT值有差异(F=9.629,P=0.000),CACG眼与POAG及正常眼CCT值均无差异(P=0.119).GS眼CCT值(564.72±31.96μm)较正常眼厚.CCT与IOP成直线正相关,眼压测量值的校正公式为眼压校正值(mmHg)=-(测得的角膜厚度μm-555μm)×(1/24).IOP经CCT校正后,OHT眼平均高估1.89mHg,NTG眼平均低估1.1mmHg,POAG眼平均高估0.80mmHg.根据经CCT校正后的IOP值,13.5%POAG眼重新诊断为NTG眼,34.5%OHT眼重新诊断为正常眼,16.7%NTG眼重新诊断为POAG眼.结论非接触式角膜内皮镜能准确地测量中央角膜厚度.OHT眼CCT较厚,而NTG眼CCT较薄.CCT测量对青光眼的分类与治疗有重要的指导意义,应作为OHT、NTG及GS的常规检查项目.     

共焦显微镜观察虹膜角膜内皮综合征及其继发性青光眼的手术治疗

目的应用共焦显微镜检查探讨虹膜角膜内皮综合征的临床特征及其继发性青光眼的手术治疗。方法 8例（8眼）虹膜角膜内皮综合征行共焦显微镜下双眼检查;描述角膜内皮的病变结构特点,分析双眼角膜内皮细胞密度、内皮细胞平均面积、六角形细胞比例及中央角膜厚度,并对6例继发性青光眼中的5例施行手术治疗。结果患眼角膜内皮细胞呈风筝样或上皮细胞样改变;细胞排列紊乱,大小不均;细胞内可见高反光的细胞核,部分可见双核。患眼和对侧眼的角膜内皮细胞密度、内皮细胞平均面积、六角形细胞比例分别为：789.7±75.8个/mm^2、2223.7±80.6个/mm^2;1106.9±89.4μm^2、379.8±20.6μm^2;17.2±1.2%、56.3±1.7%,下降明显。二者的中央角膜厚度相当。4例继发性青光眼手术后眼压控制正常,另1例手术无效。结论共焦显微镜能够发现ICE患者的角膜内皮细胞的特征性改变;对该病的诊断具有很高的临床意义。并发继发性青光眼要及时手术治疗控制眼压。     

虹膜角膜内皮综合征继发青光眼的临床治疗

目的:探讨虹膜角膜内皮综合征继发青光眼的临床治疗方法及效果。方法:对2005-08/2009-08连续收治的10例12眼ICE综合征继发青光眼患者随访3~40mo,观察其手术方法及术后眼压、视力情况。结果:所有患眼均行复合式小梁切除术,成功8眼,失败眼中3眼行Ahmed青光眼阀植入术成功,1眼行睫状体光凝术。结论:复合式小梁切除术和Ahmed青光眼阀植入术是治疗虹膜角膜内皮综合征继发青光眼的有效手术方法。     

眼前节Nd-YAG激光前后角膜内皮的变化

目的采用非接触角膜内皮显微镜观察Nd-YAG激光虹膜切除术、后发膜性白内障切开术前后角膜内皮有无变化.方法对48人80眼(急性闭角型青光眼38人66眼,后发膜性白内障10人14眼)在激光前和激光后一周、一月进行角膜内皮观察.观察指标为细胞密度、平均值、六角型细胞百分比等.结果激光前后闭角型青光眼在一周时角膜内皮细胞密度、六角型细胞的百分数有差异.后发膜性白内障术后一周最大细胞值有差异,一月时均恢复正常.为探讨眼压对角膜内皮的影响,以术后眼压升高5 mmHg(1 mmHg=0.133 kPa)为标准,＞5 mmHg组与≤5 mmHg组在术后一周比较细胞密度、平均值、最大细胞面积三方面均有差异,一月时恢复正常.结论激光手术对角膜内皮有一定影响,术后前节炎症控制及时,注意观察眼压一旦升高立即降压,术前应用降眼压药均能对角膜内皮起到保护作用.     

利用白星超声乳化技术治疗青光眼术后白内障的临床对比研究

目的探讨白星超声乳化技术对治疗青光眼术后白内障的优越性。方法对青光眼术后白内障患者采取随即分组,研究组采用白星超声乳化技术,对照组采用普通超声乳化技术,对比两组术后视力、手术并发症及角膜内皮数量变化等。结果两组术后视力恢复无显著性差异;对照组出现角膜水肿、中重度房水闪辉的机率高于研究组;研究组术后角膜内皮减少数量低于对照组。结论利用白星超声乳化技术透明角膜切口治疗青光眼术后复杂白内障具有损伤小,并发症少,恢复快的特点。     

Strabisme Alternant - Etude clinique - traitement

The author defines motor and sensory alternation: the term alternation should not be used in isolation, it should always be accompanied by the name of the parameter concerned. Sensory alternation is always found together with motor alternation but the reverse is not true.The examining criteria for a diagnosis of sensory alternation are given, sensory alternation must not be confused with alternating inhibition. Working from clinical observations of cases of motor alternating strabismus, the author selects 2 types of binocular sensory relations which allow one to differentiate between:- cases of primary alternating strabismus- cases of secondary alternating strabismusThese forms will develop in different ways; in both cases a cure is possible providing that the right treatment is prescribed and once prescribed carefully followed, etc. It is always a case of serious forms of strabismus whose developmental period is spread over several years.According to the authors, the frequency of cases of true primary strabismus is from 1–3%, the frequency of cases of secondary alternating strabismus varies according to the type of therapy practised on cases of monocular strabismus with amblyopia. These latter will become cases of alternating strabismus under the influence of certain types of therapy carried out over several years (penalization, rocking, alternated occlusion, etc...).Experimental data on kittens confirm clinical data; kittens placed in abnormal environments during the sensitive period will show modification in the distribution of cortical cells and the absence of binocular cells (either because the excitation of the two eyes was not simultaneous, or not identical: artificial strabismus, occlusion, opaque glasses). This disturbances become irreversible after a certain period of exposure (a function of age, length of exposure, etc...).It is thus necessary to bear in mind: 1) the iatrogenic risks of certain orthoptic treatments, 2) the necessity for a binocular form of treatment as soon as possible, as once a certain stage is passed, cortical plasticity diminishes and the elaboration of normal binocular relations becomes impossible.

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Effects of Adenosine Agonists on Intraocular Pressure and Aqueous Humor Dynamics in Cynomolgus Monkeys

The effects of single or multiple topical doses of the relatively selective A₁adenosine receptor agonists (R)-phenylisopropyladenosine (R-PIA) and N⁶-cyclohexyladenosine (CHA) on intraocular pressure (IOP), aqueous humor flow (AHF) and outflow facility were investigated in ocular normotensive cynomolgus monkeys. IOP and AHF were determined, under ketamine anesthesia, by Goldmann applanation tonometry and fluorophotometry, respectively. Total outflow facility was determined by anterior chamber perfusion under pentobarbital anesthesia. A single unilateral topical application of R-PIA (20–250 μg) or CHA (20–500 μg) produced ocular hypertension (maximum rise=4.9 or 3.5 mmHg) within 30 min, followed by ocular hypotension (maximum fall=2.1 or 3.6 mmHg) from 2–6 hr. The relatively selective adenosine A₂antagonist 3,7-dimethyl-1-propargylxanthine (DMPX, 320 μg) inhibited the early hypertension, without influencing the hypotension. Neither 100 μg R-PIA nor 500 μg CHA clearly altered AHF. Total outflow facility was increased by 71% 3 hr after 100 μg R-PIA. In conclusion, the early ocular hypertension produced by topical adenosine agonists in cynomolgus monkeys is associated with the activation of adenosine A₂receptors, while the subsequent hypotension appears to be mediated by adenosine A₁receptors and results primarily from increased outflow facility.