Diabetic retinopathy is a common complication of diabetes in the eye, microvascular disease-related complications seriously affect the patient's visual and quality of life. Endothelial nitric oxide synthase, a rate-limiting enzyme in the metabolism of vascular endothelial cells, may play a role in the progression of diabetic retinopathy. This review summarizes the progress of endothelial nitric oxide synthase in diabetic retinopathy.

Background Posterior capsule opacification(PCO) is the main cause inducing low vision after extacapsular cataract extraction. Our previous study determined that polylysine-ethylene diamine tetraacetic acid (EDTA) (PLE) can suppress the incidence of PCO. Objective The goal of this experiment was to investigate the inhibition of polylysine-EDTA on rabbit lens epithelial cells (LECs) proliferation in vitro and the effective concentrations of polylysine-EDTA. Methods The anterior capsular membranes from 10 3-month-old clean New Zealand white rabbits were digested and then cultured to obtain the LECs. The second and third generation of LECs were inoculated on the 96-hole culture plate with the cell density of the 1 × 105/ml. 12.5,25.0,50. 0,100. 0 μmol/Lof PLE were added into the culture medium for 48 hours respectively,and the DMSO medium was used at the same way as the control group. The proliferation of the LECs was then detected by MTT method and the inhibitory rate of PLE on LECs growth was calculated. Results LECs grew at a near normal state in ≤25.0 μmol/L PLE groups,however,cultured LECs were out of shape and the numbers decreased with the weakened adhesion ability in ≥50.0 μ mol/L PLE groups. The A490 values of LECs were 0. 278±0. 013,0. 266±0. 028,0. 260±0. 022 and 0. 247±0. 012 in 12. 5,25.0,50. 0, 100. 0 μmol/L polylysine-EDTA groups respectively and were lower than 0. 311 ±0. 038 of DMSO control group( P=0. 035,0. 011,0. 009,0.013 ). The inhibitory rates of 12. 5,25.0,50. 0, 100.0 μmoL/L PLE on LECs proliferation were 10.61％ , 14.47％ , 16.40％ and 20. 58％ respectively. Conclusions Polylysine-EDTA can inhibit the growth and proliferation of LECs in vitro at a dose-dependent manner.

PURPOSE:To evaluate the efficacy and postoperative outcomes of bimanual and micro-coaxial phacoemulsification with torsional ultrasound. METHODS:In this prospective randomized series, eyes with age-related cataract were randomly divided into bimanual phacoemulsification and micro-coaxial phacoemulsification groups. Data included preoperative and postoperative corrected distance visual acuity (CDVA), central/temporal corneal thickness, endothelial cell density and intraoperative ultrasound time, cumulative dissipated energy and balanced salt solution volume. RESULTS:The study evaluated 89 patients (89 eyes). When compared between micro-coaxial and bimanual phaco groups, ultrasound time (57 ± 24 second versus 85 ± 40 second, p < 0.01), cumulative dissipated energy (10 ± 7 versus 14 ± 7, p = 0.01) and balanced salt solution volume (55 ± 19 ml l versus 75 ± 20 ml, p < 0.01) were significantly lower in micro-coaxial phaco group. At 1 day, there were no statistically significant differences in CDVA (p = 0.68) or central corneal thickness (p = 0.48) between two groups; temporal corneal thickness was statistically significantly thicker in bimanual phaco group (1247 ± 123 μm) than that in micro-coaxial phaco group (1108 ± 131 μm, p = 0.01). There were no statistically significant differences in CDVA, central/temporal corneal thickness, or endothelial cell density between two groups 30 days postoperatively (all p values >0.05). CONCLUSION:With rapid visual rehabilitation and comparable endothelial cell loss, both bimanual and micro-coaxial phacoemulsification procedures with torsional ultrasound are efficient for moderate nuclear cataract extraction.

PURPOSE:We aimed to investigate the ultrastructures of clear corneal incisions 24 hours after phacoemulsification using anterior segment optical coherence tomography (AS-OCT).METHODS:Sixty eyes of 60 patients scheduled for cataract surgery were randomly selected. All eyes underwent the same phacoemulsification procedure carried out by one experienced surgeon. Two-plane temporal clear corneal tunnel incisions were performed. The same types of intraocular lens and implant system were used in all patients. Images of the ultrastructures of the corneal incisions were taken using AS-OCT before and 1 day after surgery.RESULTS:Corneal thickness increased at the incision site after surgery in all eyes (p < 0.001). Epithelial bulla in the incision region was seen in two eyes (3%). Gaping at the internal aspect of the corneal wound was seen in 42 eyes (70%). Eyes with gaping had thicker localized cornea (p = 0.002). Descemet's membrane detachment was seen in 49 eyes (82%); this seemed to be associated with lower preoperative intraocular pressure (p = 0.01).CONCLUSIONS:Anterior segment OCT provides sensitive and detailed measurements of the ultrastructures in clear corneal incision.

PURPOSE:To evaluate the efficiency of torsional ultrasound (US) under different vacuum levels in eyes with cataract with different degrees of nuclear density. SETTING:Cataract Service, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China. METHODS:In this prospective randomized series, eyes with age-related cataract were divided into 3 groups based on nuclear density. Eyes in each group were randomly assigned to 1 of 3 subgroups and treated with phacoemulsification under vacuum of 250 mm Hg (subgroup 1), 450 mm Hg (subgroup 2), or 600 mm Hg (subgroup 3). Data included preoperative and postoperative corrected distance visual acuity (CDVA), endothelial cell density, and central corneal thickness (CCT) and intraoperative US time and cumulative dissipated energy (CDE). RESULTS:The study evaluated 998 patients (1073 eyes). In each group, there was a statistically significant decrease in US time, CDE, and postoperative endothelial cell loss with increased vacuum (P<.05). At 1 day and 7 days, the CDVA was statistically significantly better in subgroups 2 and 3 (P<.05) and the CCT was thinner when vacuum was higher. There was no statistically significant difference in CDVA and CCT between subgroups 30 days postoperatively (P>.05). CONCLUSIONS:Torsional US with a high vacuum level was safe for cataract extraction. With less US energy and endothelial cell loss, torsional US was more efficient than with higher vacuum levels with lower levels.

PURPOSE:To assess lens thickness (LT) measurements with anterior segment optical coherence tomography (AS-OCT) in comparison with A-scan ultrasonography (A-scan US).METHODS:Enrolled were 66 eyes of 48 phakic elderly volunteers aged > or = 50 years and 56 eyes of 56 young participants aged 18 to 40 years. LT was measured with the internal manual caliper tools in AS-OCT. The A-scan US measurements were based on an average of 10 consecutive automatic measurements. Reproducibility was assessed by three measurements each with AS-OCT and A-scan US independently obtained by two observers who were masked to one another's results.RESULTS:The failure rates of AS-OCT and A-scan US were 9.1% and 7.6%, respectively, in elderly subjects, but no failure was observed in young subjects. The LT values measured by AS-OCT were significantly greater than A-scan US; the paired difference was 0.135 mm in elderly and 0.101 mm in young subjects (P < 0.001). These differences did not correlate with the nuclear cataract grades (r = 0.078, P = 0.558). Intraobserver agreement on AS-OCT (95% limits of agreement [LoA]: -0.049 to +0.045 mm; ICC: 0.999) was better than A-scan US (95%LoA: -0.194 to +0.218 mm; ICC: 0.974). The 95% LoA of interobserver agreement using AS-OCT and A-scan were -0.084 to +0.073 and -0.278 to +0.239 mm, respectively, and the ICCs were 0.996 and 0.960, respectively.CONCLUSIONS:AS-OCT can be used to measure lens thickness in most eyes with clear or opacified lenses. It appears to be an alternative means of measuring lens thickness, particularly when a noncontact method is needed.

Objective Posterior capsular opacification (PCO) is one of the most common complications after cataract surgery.The major cause of PCO is the proliferation of residual lens epithelial cells (LECs)after surgery.This study was to determine the feasibility of using a polylysine-EDTA (PLE) conjugate to lens capsule during surgery to remove LECs and its prevention for PCO. Methods EDTA was conjugated to polylysine using (1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride following the instructions of Pierce.Extracapsular cataract extraction (ECCE) was performed on 18 eyes of 9 Japanese white rabbits,and 5 mL of 20 mmol/L EDTA or PLE containing 10 mmol/L EDTA was injected into the capsular bag separately in 6 eyes for 2 minutes and removed using compound sodium chloride injection,and the equal amount compound sodium chloride injection was used in 6 control eyes.Ocular anterior segment inflammation,including cornea,anterior chamber and posterior capsule in postoperation was assessed under the slitlamp microscope.The rabbits were sacrificed and the eyes were enucleated in the 28th day and the section of eye tissue was prepared for histological examination under the light microscope. Results Some inflammation was seen in the all 18 eyes in 3 days following surgery and diminished 2 weeks later following the use of antimicrobial.Obvious cellular proliferation was seen in the anterior capsular membrane,showing the spindle line of cells over 10 layers at equator of lens in the control group.A severer cellular proliferation was seen in the EDTA group.However,Only a few residual cells were found and there was not obvious proliferation on the anterior capsular membrane in PLE group. Conclusion PLE presents an ideal result in removing the residual LECs and decreasing the proliferation in comparison with EDTA.

Objective To investigate the ultrastructures of clear corneal incisions after phacoemulsification using anterior segment optical coherence tomography(AS-OCT).Methods Sixty eyes of 60 patients scheduled for cataract surgery were randomly selected.All eyes underwent the same phacoemulsification procedure through temporal clear corneal tunnel incisions.Images of the ultrastructures of the corneal incisions were taken using AS-OCT before and 1 day after surgery.Results Corneal thickness increased at the incision site after surgery in all eyes(P<0.05);Gaping at the endothelial aspect of the corneal wound was seen in 42 eyes(70%);Eyes with endothelial gaping had thicker localized cornea(P<0.05),Descemet's membrane detachment was seen in 49 eyes(81.6%).Conclusion AS-OCT imaging is able to detectchanges of the epithelium、stroma and Descemet’s membrane at the clear corneal incisions in a more detailed fashion.

超声乳化白内障摘除联合人工晶状体植入术是当今白内障复明手术的主流术式.随着科技的进步及人民生活水平的提高,白内障手术已从复明性手术发展为屈光性手术.手术者面临的压力也因此日趋严峻.如何最大程度的改善白内障术后患者的视觉质量成为当前的研究热点,其中人工晶状体度数的预测成为重中之重,因此精确测量前房深度具有重要意义.

目的 探讨一种新的超声振动模式-扭动模式(Torsional)用于白内障超声乳化吸除的有效性安全性.方法 病例来自中山大学中山眼科中心,诊断单纯性老年白内障对其进行随机分组并行超声乳化白内障吸除,一组选用扭动模式,而另一组选用常规模式,记录术中所使用的超声时间(Ultrasound Time,UST)及超声能量(Cumulative Dissipated Energy,CDE),并比较术后角膜水肿程度、角膜厚度、术后的最佳矫正视力及角膜内皮细胞的丢失率.结果 术中所使用的超声时间及超声能量比较,扭动模式组较常规模式组低,对于1、2、3、4级核,平均UST扭动模式组为8.32,18.45,29.48和48.39秒,而常规模式组为10.25,25.14,36.45和61.44秒;扭动模式组平均超声能量为0.94,3.13,7.47和14.08,常规模式组为1.25,4.18,8.59,16.51,之间的差异具有统计学意义.术后的平均最佳矫正视力比较,术后1天及术后7天扭动模式组较常规模式组高,而术后1月观察差异不具有统计学意义.角膜水肿及平均角膜中央厚度比较,术后1天及7天扭动模式组较常规模式组角膜水肿轻,术后30天比较它们之间的差异不具有统计学意义.术后7天及30天平均角膜内皮细胞计数比较,扭动模式组较常规超乳模式组高,丢失率低.结论 扭动模式超声乳化白内障吸除较传统超乳模式相比,是一种高效安全的超声乳化振动模式,较传统模式相比可以减少术中的超声时间及超声能量,并减少对眼内组织特别是角膜内皮细胞的损伤。

目的 探讨眼前段光学相干断层扫描仪(AC-OCT)检测前房深度(ACD)和晶状体厚度(LT)的一致性与可重复性.方法 对30例受试者(30只眼)的中央前房和晶状体,采用ACOCT分别由测量者甲和乙,以及测量者甲在两个不同的时间点进行水平方向扫描;对其中的10例受试者(10只眼)的中央前房和晶状体水平方向扫描重复10次.采用类内相关系数(ICC)和变异系数(CV)作为评价测量的一致性,采用变异系数(CV)作为评价测量的可重复性.结果 ACD和LT的平均值分别为(3.16±0.27)mm和(3.90±0.26)mm.测量者间ACD和LT的ICC值分别为0.996(F=499.347,P=0.000)和0.996(F=539.069,P=0.000);变异系数的平均值分别为0.47%±0.24%和0.37%±0.20%.测量者内ACD和LT的ICC值分别为0.999(F=2039.611,P=0.000)和0.999(F=1654.961,P=0.000);变异系数的平均值分别为0.18%±0.22%和0.19%±0.16%.10例受试者(10只眼)的ACD及LT扫描10次的变异系数平均值分别为0.39%±0.12%和0.30%±0.14%.结论 ACOCT测量ACD和LT的一致性与可重复性较好,是一种精确可靠的测量ACD与LT的工具.

目的 利用波阵面像差检测仪探讨准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)中角膜瓣制作与激光扫描切削在时间上有延迟时对手术效果的影响.方法 30例(60眼)近视患者自愿接受LASIK手术.手术方式基本同常规LASIK术,不同点为:用角膜刀先后制作左、右眼带蒂上方角膜瓣,再分别对右、左眼角膜基质层行激光切削.于术前、术后第1周、第1个月、第3个月进行双眼波阵面像差的检测和分析.结果 术前双眼波阵面像差均方根值(root means squares,RMS)检测各组值比较差异无显著性(P＞0.05).术后第1周在中小瞳孔直径下,右、左眼RMS2和RMSg比较差异有显著性(P＜0.05).术后第1个月仅在小瞳孔直径下,右、左眼RMS2比较差异有显著性(P＜0.05).RMS1、RMS3-6、RMSg及RMSh各组值比较差异均无显著性(P＞0.05).术后第3个月双眼RMS各组值比较差异均无显著性(P＞0.05).术后各时期双眼裸眼视力、最佳矫正视力、平均屈光度比较差异均无显著性(P＞0.05).结论 该手术方式步骤衔接紧密,省出有效时间消毒显微角膜板层刀和相关器械,对术后稳定效果无影响,适宜于对大批患者集中进行手术,易于推广应用.

近年来,随着超声乳化白内障吸除术的发展及对高度近视合并白内障手术认识的不断加深,我们对15例高度近视合并白内障患者施行颞侧透明角膜切口超声白内障吸除人工晶体植入,临床效果满意,现报告如下.

黄斑裂孔(Macular holes,MH)性视网膜脱离(简称网脱),以往采用电凝,冷凝和巩膜外加压,黄斑兜带术等手术方式治疗,术中定位及操作极为困难,并发症多,手术造成黄斑区永久损害、视力差,因此,采用对视力损害小且并发症少的手术方法尤为重要.我科于1999年4月～2000年12月应用玻璃体视网膜手术(Vitreoretinal Surgery,VRS)治疗20例20眼MH网脱,取得满意效果,报道如下.

1992年Fine开展透明角膜隧道切口用于白内障手术后,国内外眼科界为追求白内障手术最佳疗效,不断革新手术,取得新进展.我院从1999年开展经颞侧透明角膜隧道切口术式超声乳化白内障吸出折叠人工晶体植入术,效果满意,报导如下.

于1998年10月～11月.对贵州水城县275例白内障患者施行了复明手术,分析如下. 1资料与方法 1.1一般资料275例(285眼),女129例,男146例,年龄3～91岁,平均58.8岁,其中老年性白内障236例(包括高度近视白内障9例),并发性白内障5例,先天性白内障28例,外伤性白内障6例.术前视力:光感～0.04 229眼,0.05～0.256眼,核混浊为Ⅲ～Ⅳ极. 1.2人工晶体选择用国产A/B超仪检查角膜曲率及测量眼轴,由电脑自动计算及打印所需人工晶体屈光度.使用国产宇宙牌后房型一体式人工晶体,屈光度为+18～+22.5D.

目的探索人发取代其它缝线在眼部美容整形中的应用.方法观察人发与其它缝线在动物组织中的病理变化及临床上的应用,人发来自健康17～28岁女性,比较缝线为无损伤缝线、丝线、羊肠线.大白兔38只,将4种缝线分别缝合于大白兔背部两侧肌层,深约3mm,观察1周、4周、12周、24周组织中的病理变化.结果证实人发明显优于其它缝线.镜下所见,人发反应最轻,然后依次为无损伤缝线、丝线、羊肠线.用于眼部美容整形手术共142例,以双重睑为例,1周的眼部肿胀反应相当于丝线一月的反应.结论人发物美价廉,来源广泛,创面保持清洁,不易污染,愈合没有蜈蚣足样瘢痕,建议应广泛用于眼部美容整形手术中.

现代常规视网膜脱离手术的关键是封闭全部视网膜裂孔,解除玻璃体视网膜间牵引,抑制增生性玻璃体视网膜病变(PVR)形成.封闭裂孔通常于术中采用电凝或冷冻,电凝对巩膜损伤较大,已逐渐淘汰;冷冻法目前在国内、国外的视网膜脱离手术中常规使用,目前临床上常用的冷凝剂一般为储于高压钢瓶内的二氧化碳(CO2)或一氧化二氮(N2O).CO2气体由高压钢瓶进入冷凝机,经导管达冷凝头.冷凝头是内空的银合金盲管,气体达冷凝头后,头端冷却达-60℃,手术中冷凝盼时间约需10～20s.本组病例采用浸冷式液氮冷冻器,冷冻头的最低温度可达-17℃,最佳冷凝时间控制在4～6s,现将1990年1月～1999年10月用液氮治疗的视网膜脱离患者768例776只眼回顾分析,报告如下.