人工晶状体的自身特性与后囊膜混浊的关系

后囊膜混浊是白内障摘除联合后房型人工晶状体植入术后导致视力下降的最主要并发症之一。选择理想的人工晶状体可以明显降低后囊膜混浊的发生 ,本文就人工晶状体的材料、设计、光学直径大小等与后囊膜混浊的关系加以综述     

人工晶状体的自身特性与后囊膜混浊的关系

后囊膜混浊是白内障除联合后房型人工晶状体植入术后导致视力下降的最主要并发症之一。选择理想的人工晶状体可以明显降低后囊膜混浊的发生，本就人工晶状体的材料、设计、光学直径大小等与后囊膜混浊的关系加以综述。     

白内障术后后囊膜混浊的发生因素

晶状体后囊膜混浊是白内障摘除联合后房型人工晶状体植入术后最常见的并发症,其发生率与人工晶状体的材料、镜片的式样,手术技术等因素均有关。新型的亲水丙烯酸和疏水丙烯酸AcrysofTM人工晶状体由于材料有良好的生物相容性及粘附性能,从而降低了后囊膜混浊的发生率。后凸型的人工晶状体、矩形锐利直角的光学边缘的人工晶状体、小切口白内障超声乳化摘除术、连续环形撕囊可以减少后囊膜混浊的发生率。     

白内障术中后囊连续环形撕囊预防后囊混浊的临床观察

目的 探讨白内障囊外摘除联合人工晶状体植入术中行后囊膜连续环形撕囊(PCCC)对预防术后后囊混浊(PCO)的作用。方法 对365例(426只眼)白内障行常规囊外摘除后行后囊膜连续环行撕囊再植入人工晶状体。结果 365例(426只眼)后囊膜连续环形撕囊均成功，人工晶状体植入囊袋中。术后随访2～3年后囊混浊未见发生。结论 在白内障囊外摘出后对后囊膜连续环形撕囊是可行的，它避免了后囊混浊产生的根本原因，对人工晶状体植入后视力无明显影响。     

不同材料的人工晶状体植入术后的临床疗效观察

目的　评价超声乳化白内障吸出联合不同材料制成的人工晶状体植入术治疗白内障的疗效。方法　将 14 5例(14 8眼 )行超声乳化白内障吸出联合人工晶状体植入术的患者分为 3组 ,术中随机植入PMMA人工晶状体、新型疏水性丙烯酸酯类、硅凝胶类折叠式人工晶状体。比较术前和术后视力、散光情况。统计术后晶状体后囊膜混浊情况及行Nd :YAG激光后囊膜切除术的情况。结果　术后早期视力、3个月后散光度数、晶状体后囊膜混浊发生率及行Nd :YAG激光后囊膜切除术的情况 ,植入折叠式人工晶状体者均优于植入非折叠式人工晶状体者。植入Canonstaar硅凝胶类折叠式人工晶状体组术后散光最小。植入AcrysofTM新型疏水性丙烯酸酯类折叠式人工晶状体组术后晶状体后囊膜混浊发生率及行Nd :YAG激光后囊膜切除术的比例最低。结论　超声乳化白内障吸出联合折叠式人工晶状体植入的临床应用效果满意。     

白内障超声乳化术后囊膜混早的多因素分析

目的：研究白内障超声乳化术后发生后囊膜混浊的相关因素。方法：采用多元逐步回归方法对可能引起后囊膜混浊的诸多因素进行分析。结果：在105例经过6-18个月临床随访的患者中,发现与后囊膜混浊的相关因素是术后第1天前房反应及人工晶状体类型,其它因素包括病人性别、年龄、白内障类型、核硬度、眼轴长度、术中超声时间等均与后囊膜混浊无关。结论：减轻术后第1天前房反应及选用丙烯酸酯类折叠式人工晶状体有助于减少后发障的发生率。     

白内障超声乳化吸除联合人工晶状体植入Ⅰ期后囊膜连续环形撕除的临床观察

目的探讨白内障超声乳化吸除联合人工晶状体植入术中Ⅰ期后囊膜连续环形撕除的临床疗效。方法对53例(60只眼)先天性白内障和后囊混浊的老年性白内障,施行白内障超声乳化吸除联合人工晶状体植入,同时行Ⅰ期后囊膜连续环形撕除,术后观察眼压、人工晶状体位置、视轴区后发障等情况。结果术中人工晶状体均顺利植入囊袋;54只眼术后视力较术前提高,术后24小时后眼压正常;术后随访3个月~2年,无发生玻璃体疝入前房,未发现人工晶状体异位或夹持,无一例出现后发障、视网膜脱离。结论白内障超声乳化吸除联合人工晶状体植入Ⅰ期后囊膜连续环形撕除是可行、安全的,能有效地治疗后囊膜混浊,预防后发障。     

后囊膜混浊的相关因素分析

目的:探讨在白内障及人工晶状体植入后,后囊膜混浊的相关因素以及预防治疗的方法。方法:根据手术方法分为单纯白内障摘除组及白内障加人工晶状体植入组,后者又根据手术方法的不同及人工晶状体的类型进行比较分析。结果:单纯摘除组与人工晶状体植入组,人工晶状体植入中,不同的手术方法及不同的人工晶状体类型其后囊膜混浊发生的频率及程度均存在较大差异。结论:选择适宜的手术方法(完全封闭技术)、优良的人工晶状体材质(疏水性丙烯酸酯和肝素处理)、特殊的形态设计(锐利边缘)就能最大程度的减少或避免后囊膜混浊的发生。     

白内障摘除人工晶状体植入术后晶状体后囊膜混浊的基础研究

晶状体后囊膜混浊是目前白内障摘除人工晶状体植入术后影响视功能恢复的主要并发症 ,其发生与手术残留的晶状体上皮细胞增殖有关。为了预防该并发症的发生 ,研究其发病机制成为眼科临床的重要任务。许多眼科医生进行了大量的基础研究工作 ,力求从根本上解决白内障摘除人工晶状体植入术后晶状体后囊膜混浊的发生。正常晶状体上皮细胞的生物学特性人眼晶状体起源于外胚层 ,由晶状体囊膜、囊膜下晶状体上皮细胞及其产物 ,即晶状体纤维组成。晶状体上皮细胞为单层立方上皮细胞 ,紧密贴附于前囊膜的内表面 ,与下方的晶状体纤维疏松连接。晶状体上…     

晶状体后囊膜混浊的研究方法及细胞生物学研究进展

晶状体后囊膜混浊(PCO)是现代白内障囊外摘除联合人工晶状体植入术术后引起视力下降的常见,有多种方法用于研究后囊膜混浊,但各有利弊.细胞调节系统在后囊膜混浊的形成发挥重要作用.本文就后囊膜混浊的不同研究方法及与后囊膜混浊有关的细胞生物学调节方式进行综述,展望防治PCO的前景.     

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.