Latent endothelial cell damage after experimental corneal cryopreservation

Ninety porcine corneas were evaluated by vital staining with alizarin red S and trypan blue in a three-step experiment. Central cell densities were counted (a) on freshly dissected corneas (n = 30), (b) on cryopreserved corneas directly after thawing (n = 30), and (c) after a postthawing organ culture interval of 24 h (n = 30). Two freezing methods were used: (a) minimum essential medium — containing 20% fetal calf serum and (b) the same but containing additionally 2% chondroitin sulfate. Directly after thawing neither method showed significant cell loss (3.9% and 3%) compared to fresh tissue. After postthawing organ culture, however, tissue that had been frozen without chondroitin sulfate displayed a cell loss of 73.5% compared to corneas of the same freezing protocol directly after thawing. Corneas in chondroitin sulfate containing medium showed a cell loss of only 33.2%. We conclude that reliable morphologic evaluation should not be obtained from cryopreserved corneas examined directly after thawing.     

Quantification of allospecific and nonspecific corneal endothelial cell damage after corneal transplantation

Purpose

To investigate the effect of host immunity (allospecific) and surgical manipulation (non-allospecific) on corneal endothelial cells (CECs) in corneal transplantation.

Methods

Draining lymph nodes and grafted C57BL/6 corneas were harvested from syngeneic recipients, allograft acceptors, and allograft rejectors (BALB/c) 1, 3, and 8 weeks after transplantation. We analyzed CEC apoptosis using an ex vivo cornea-in-the-cup assay, and visualized cell-to-cell junctions using immunohistochemical staining (ZO-1). Automatic cell analysis using Confoscan software was used to measure CEC density as well as changes in CEC morphology by quantifying the coefficient of variation in cell size (polymegethism) and shape (pleomorphism).

Results

The cornea-in-the-cup assay showed that allogeneic acceptor T cells and to an even greater extent rejector T cells (but not syngeneic T cells) induced CEC apoptosis. CEC density after corneal transplantation was significantly reduced in allogeneic acceptors compared with syngeneic grafts (P<0.001), and CEC density was even further reduced in the allo-rejector group compared with the allo-acceptor group. Allogeneic grafts showed a greater increase in the coefficient of variation in cell size (polymegethism) when compared with syngeneic grafts 1 week after transplantation (P=P<0.001). However, pleomorphism was not significantly different between syngeneic and allo-acceptor grafts, indicating that polymegethism (but not pleomorphism or cell density) is a sensitive indicator of the effect of alloimmunity on CECs.

Conclusions

Our data demonstrate that host alloimmunity rather than surgical manipulation alone is the major cause of CEC damage in corneal transplantation, and such morphologic changes of CECs can be detected before the clinically visible onset of allograft rejection.     

Glaucoma-associated corneal endothelial cell damage: A review

The corneal endothelium is critical in maintaining a healthy and clear cornea. Corneal endothelial cells have a significant reserve function, but preservation of these cells is paramount as they have limited regenerative capacity. Glaucoma is a prevalent disease, and damage to the corneal endothelium may be caused by the disease process itself as well as by its treatment. The mechanisms involved in glaucoma-associated damage to the corneal endothelium need further investigation. Understanding how glaucoma and glaucoma surgery impact the endothelium is important for protecting corneal clarity and visual acuity in all glaucoma patients, including those undergoing corneal transplant. We will discuss a range of identified factors that may impact corneal endothelial cell health in glaucoma, including intraocular pressure, glaucoma medications, surgical glaucoma management, mechanical forces, and alterations in the aqueous environment.     

白内障超声乳化手术与角膜内皮细胞损伤

白内障是目前眼科最常见的致盲性眼病,超声乳化手术以切口小、反应轻、术后恢复快已被世界公认为最先进而成熟的主流手术方式。现代白内障手术从复明手术逐渐向以改善视功能为目标的屈光性手术发展。角膜作为屈光系统中最重要的组织,其透明度的维持很大程度上取决于角膜内皮细胞的功能,白内障手术不可避免地在一定程度上损伤角膜内皮细胞,由此引起的角膜水肿、混浊甚至失代偿等并发症严重的影响了白内障患者术后视力的改善,本文对白内障超声乳化手术及其角膜内皮细胞损伤因素进行综述。     

Effect of topical steroids on corneal epithelial healing after vitreoretinal surgery

PURPOSE: Topical steroid use is usually avoided in cases of corneal epithelial defect. We evaluated the effect of topical steroid treatment on corneal epithelial healing after epithelial debridement in vitreoretinal surgery. METHODS: Our study population included 85 eyes undergoing vitreoretinal surgeries in our clinic. We prospectively compared the duration of corneal epithelial wound healing in 43 eyes in which topical dexamethasone was used with that in 42 eyes in which topical dexamethasone was not used in the early postoperative period after epithelial debridement. Factors that may retard corneal epithelial healing, including pre- and intraoperative topical solutions, median operative time, the presence of diabetes mellitus, prior ocular surgeries, pseudophakia, aphakia and the presence of intraocular gas or silicone oil in aphakic patients, were not significantly different between the two groups. RESULTS: The mean corneal epithelial defect closure time was 59.7 +/- 2.6 hours (mean +/- SEM) in the group receiving topical steroid treatment, and 61.9 +/- 2.6 hours in the group that did not receive steroids. CONCLUSION: Topical dexamethasone administered five times/day did not significantly retard corneal epithelial healing in subjects undergoing vitreoretinal surgery with postoperative topical steroid treatment, compared with subjects who did not receive steroid treatment.     

白内障患者术后角膜内皮细胞计数减少的多因素分析

目的：探讨白内障患者超声乳化术后影响角膜内皮细胞数目减少的相关因素。

方法：选取我院眼科采用超声乳化术治疗的98例120眼进行回顾性分析,收集时间2014-07/2016-07; 根据患者术后2mo复查角膜中央内皮细胞密度与术前进行比较分为严重丢失组52例67眼(角膜中央内皮细胞丢失率≥12.3%),一般丢失组46例53眼(角膜中央内皮细胞丢失率<12.3%),对比两组患者的一般资料、手术相关指标,采用非条件Logistic回归分析法探讨影响白内障患者术后角膜内皮细胞丢失的影响因素。

结果：严重丢失组和一般丢失组的性别、合并高血压、合并糖尿病、合并高血脂、浅前房、角膜直径增大、注吸时间比较,差异均无统计学意义(P>0.05); 两组比较的Emery晶状体核硬度分级、超声能量、超声乳化时间、年龄构成差异具有统计学意义(P<0.05); 采用非条件Logistic分析法,结果显示Emery晶状体核硬度分级增高、超声能量增加、超声乳化时间较长、年龄增大是超声乳化术治疗后角膜内皮细胞数目严重减少的独立危险因素(P<0.05)。

结论：白内障患者超声乳化术后影响角膜内皮细胞数目减少的主要因素为Emery晶状体核硬度分级增高、超声能量增加、超声乳化时间较长、年龄增大。     

Postoperative corneal swelling correlates strongly to corneal endothelial cell loss after phacoemulsification cataract surgery

PURPOSE: To evaluate postoperative corneal swelling as a predictor of corneal endothelial cell loss after phacoemulsification cataract surgery. DESIGN: Prospective observational case series. METHODS: Thirty patients planned for routine phacoemulsification cataract surgery were included. Ultrasonic pachymetry and specular microscope endothelial photography of the central and nasal portions of the cornea and Orbscan II slit-scan tomography were performed preoperatively and the day after surgery. The 30 patients were selected from 41 patients based on their increase in central corneal thickness: the first 10 cases with a <5% increase, the first 10 with a 6% to 20% increase, and the first 10 with a > or =20% increase. The same measurements were repeated after 1, 2, and 3 months. The primary outcome measures were corneal endothelial cell loss and increase in pachymetry. Several other parameters were also registered, including age, degree of cataract, visual acuity, phacoemulsification time and energy, total operation time, and the amount of infusion fluid used. RESULTS: The central corneal swelling at postoperative day 1 was strongly correlated with the central corneal endothelial cell loss at 3 months (R(2) = 0.785, P < .001). CONCLUSIONS: In this series, with large variations in the corneal swelling at the first postoperative day, the degree of permanent corneal endothelial damage was reflected in the degree of early postoperative corneal swelling. Measuring the difference in pachymetry at postoperative day 1 is a useful way to assess the effects on the corneal endothelium exerted by the phacoemulsification procedure.     

儿童白内障术后角膜内皮细胞损失的评估

目的探讨儿童白内障行晶体囊外摘除加人工晶体植入和人工晶体植入加前部玻璃体切割两种术式对角膜内皮的损伤作用.方法随机选12例16眼先天性白内障住院患者,分两组,第一组行晶体囊外摘除加人工晶体植入术,第二组行人工晶体植入加前部玻璃体切割术,术前、术后两周分别行角膜内皮镜检查,评估内皮细胞丢失率、变异系数的改变和六角形细胞的变化.结果手术后第一组平均内皮细胞丢失254.35个/mm2,第二组平均内皮细胞丢失297.05/个mm2,两组间内皮细胞计数和形态的改变无统计学意义.结论人工晶体植入加前部玻璃体切割术对角膜内皮损伤在可接受范围内.     

白内障超声乳化术前及术中参数对角膜内皮的影响

目的 评估白内障超声乳化手术的一些术前以及术中参数对术后角膜内皮损伤的影响.方法 83例患者(100只眼)行白内障超声乳化手术.术前、术中记录患者年龄、核硬度、前房深度(ACD)、眼轴长度、切口累计消散能量(CDE)、注吸时间以及液流量.术前以及术后2周测量患者中央角膜内皮细胞密度(CED)、细胞变异度(CV)、平均细胞面积(AVG)、六边形细胞比率.结果 术后2周,角膜内皮细胞平均丢失(377.14 ±283.00) /mm2,丢失率为(14.37±10.59)％,术前、术后内皮细胞密度差异有统计学意义(P ＜0.001).术后角膜内皮形态发生改变,六边形细胞比率减少,术前、术后患者的CV、AVG、六边形细胞比率差别有统计学意义(P ＜0.001).内皮细胞丢失量与核硬度、超声能量、前房深度、年龄有一定的相关性(分别为P ＜0.001,P=0.008,P=0.005,P=0.035),但与液流量、注吸时间、眼轴长度无相关(分别为P =0.420,P=0.607,P=0.823).结论 白内障超声乳化手术后内皮细胞损伤的因素是多方面的,例如:核硬度、超声能量、前房深度等.应该提高手术技巧以及手术设备减轻对角膜内皮的损伤.     

不同白内障手术切口对兔角膜内皮细胞的影响

目的 比较不同白内障手术切口对兔角膜内皮细胞密度的影响。探讨手术切口损伤角膜内皮的机制，为术中减少角膜内皮损伤创造有利条件。方法 将60只兔眼随机分为三组：A组(小切口组)、B组(中切口组)、C组(大切口组)，每组20只眼。分别于术前，术后3、14、30d观察免角膜上方和中央区内皮细胞密度的改变，计算内皮细胞丢失率，进行统计分析，比较各组内皮细胞丢失率之间的差异。结果 随手术切口的缩小，上方角膜内皮细胞丢失率呈下降趋势，角膜中央区的内皮细胞丢失率随上方角膜内皮细胞丢失率的下降而下降。A组与B组术后各期内皮细胞丢失率无差异，而A组与C组、B组与C组之间内皮细胞丢失率存在显著性差异。结论 白内障手术切口越小对角膜内皮细胞的保护越好，自闭性小切口应是临床白内障手术的理想切口。     

小梁切除手术前后角膜内皮细胞观察

目的:观察小梁切除术对角膜内皮细胞有无影响.方法:采用非接触型角膜内皮显微镜,对40例56眼行小梁切除术的患者,做术前术后角膜内皮细胞密度和细胞形态学的检测.结果:行青光眼小梁切除术的患者40例56眼,除了4眼有2度浅前房的患者外,其余52眼术前角膜内皮细胞密度均值为2 580.90±323.20个/mm2,术后1 wk均值为2 558.28±341.83/mm2,细胞形态学方面,最大细胞面积、最小细胞面积、平均细胞面积、细胞面积标准差、细胞面积变异系数、六角形细胞百分数术前术后无显著性差异(P＞0.05).结论:在通常情况下,小梁切除术不会对角膜内皮细胞产生不良影响.     

Evaluation of early corneal endothelial cell loss in bimanual microincision cataract surgery (MICS) in comparison with standard phacoemulsification

PURPOSE: To analyze early corneal endothelial cell loss due to microincision cataract surgery (MICS) in comparison with standard phacoemulsification through the temporal clear corneal incision. METHODS: The examined group consisted of a nonrandomized, consecutive prospective series of 20 eyes of 20 patients who underwent uneventful microincision cataract surgery. Twenty eyes of 20 patients who underwent standard phacoemulsification with foldable intraocular lens (IOL) implantation served as a reference group. Patients with corneal disorders, contact lens wear, previous intraocular surgery, and a history of ocular trauma were excluded from the study. Patients were examined preoperatively and 10 days postoperatively. The following items were evaluated in this study: corneal endothelial cell density, intraoperative phaco power, effective phaco time, as well as pre- and postoperative visual acuity. Corneal endothelial cell counts were done in the central part of the cornea using a non-contact Topcon SP 2000P specular microscope before and 10 days after the surgery. The measurements were performed in a semiautomated, masked manner. Statistical analysis was done using nonparametric tests (Wilcoxon signed-ranks test and Mann-Whitney U test). RESULTS: All patients in the study underwent uneventful surgery. Best-corrected visual acuity (BCVA) examined 10 days postoperatively in the MICS group was 0.94+/-0.094, whereas in the standard phacoemulsification group it was 0.90+/-0.094. There was no significant difference between BCVA in the two groups (Mann Whitney U two-tailed test: p>0.05). In both groups there was a significant decrease in postoperative endothelial cell densities (ECDs) when compared to preoperative values. Mean postoperative ECDs were 2235+/-418 cells/mm2 in the MICS group and 2079+/-399 cells/mm2 in the standard phacoemulsification group; the difference was not statistically significant (Mann-Whitney U test: p>0.05). Patients in the MICS group lost an average of 9.5% of cells, whereas patients after standard phacoemulsification lost about 7.6% of cells. This difference was statistically insignificant. CONCLUSIONS: Microincision cataract surgery induced corneal endothelial cell loss similar to a standard phacoemulsification and allowed excellent visual results in this series of patients. These results support the use of MICS technique for cataract surgery.     

后囊浑浊激光治疗术后角膜内皮细胞的观察

目的 观察Ｎｄ：ＹＡＧ激光后囊切开术对角膜内皮细胞的影响。方法 对５２眼后囊浑浊行Ｎｄ：ＹＡＧ激光后囊切开术。术前、术后１周,１月及３月检查角膜内皮细胞密度。结果 术后１周、１月、３月角膜内皮细胞密度均较术前下降,内皮细胞丢失率依次为２．６８％、５．６５％和６．２８％。有统计学差异（ｔ值分别为２．２４７,３．５４１和２．４４９,Ｐ〈０．０５）。内皮细胞丢失与每次能量有显著相关性（ｒ＝０．４１９,Ｐ     

糖尿病性白内障术后角膜内皮细胞的变化

目的研究糖尿病性白内障患者及合并高血压的糖尿病性白内障患者超声乳化术后角膜内皮细胞数量及形态学变化情况。方法随机选取行白内障手术的单纯老年性白内障患者40例(48眼)为对照组,糖尿病性白内障患者36例(42眼)为糖尿病组,以及合并高血压的糖尿病性白内障患者34例(44眼)为糖尿病合并高血压组;采用角膜内皮计对术前及术后1周、1个月角膜中央区的角膜内皮细胞进行计数,并观察角膜内皮细胞密度、细胞面积、六角形细胞百分比、变异系数变化情况。结果术前糖尿病组与对照组相比,六角形细胞比例均下降,细胞变异系数均增加,差异均有统计学意义(均为P<0.05),糖尿病合并高血压组六角形细胞比例进一步下降,变异系数进一步增加,与糖尿病组相比,差异亦均有统计学意义(均为P<0.05)。术后1周,糖尿病组角膜内皮细胞密度、细胞面积、六角形细胞比例、细胞变异系数分别为(2458.00±349.23)mm-2、(390.65±118.55)μm2、(46.18±9.24)%以及45.01±6.13,糖尿病合并高血压组分别为(2251.83±368.41)mm-2、(390.12±231.44)μm2、(42.73±8.75)%以及48.81±5.04,二者相比,六角形细胞比例和细胞变异系数间差异有统计学意义(均为P<0.05);术后1个月,糖尿病组和糖尿病合并高血压组六角形细胞比例均进一步降低,分别为(40.72±4.60)%和(36.91±7.35)%,细胞变异系数进一步增加,分别为50.55±9.25和55.25±9.83,两组相比差异均有统计学意义(均为P<0.05)。结论糖尿病性白内障患者角膜内皮细胞状况较单纯老年性白内障患者差;糖尿病性白内障患者以及合并高血压的糖尿病性白内障患者角膜内皮在超声乳化术中都更易受到损害。     

补气在视网膜玻璃体手术后的应用

目的探讨玻璃体手术、气体填充后补气的方法、作用与效果。方法回顾分析１９９６～１９９８年我院施行玻璃体切除、气体填充及术后补气２３７例患者的临床资料,占同期玻璃体手术、气体填充患者的２９．２２％。结果痊愈率为９１．１４％,同期所有玻璃体手术、气体填充痊愈率为７７．４４％。此手术未见严重并发症。结论补气,是玻璃体手术、气体填充术后重要的后续手术,安全有效。首选“双针法”气液交换,并注入２０～４０％Ｃ３Ｆ８为宜。     

Scleral ulceration after vitreoretinal surgery

Scleral ulceration after ocular surgery is a rare but serious complication. Determination of the underlying systemic and local causes is critical for treatment. An unusual case of ischemic scleral ulceration after vitreoretinal surgery in a diabetic patient is reported. Patient was successfully treated with a pedicle conjunctival graft.     

青光眼术后低角膜内皮细胞密度白内障手术26例临床分析

目的观察抗青光眼小梁切除术后低角膜内皮细胞密度白内障患者行巩膜隧道小切口摘出联合肝素修饰人工晶状体植入术的疗效及并发症。方法选取我院抗青光眼小梁切除术后低角膜内皮细胞密度白内障患者22例(26眼),行巩膜隧道小切口白内障摘出联合肝素修饰人工晶状体植入术,对比观察术前与术后视力、眼压、角膜内皮细胞密度及术后并发症。结果术前与术后3个月矫正视力比较,除1眼患者术后因视神经萎缩明显、视力无明显改善外,余25眼患者术后视力较术前均有不同程度的提高;术前角膜内皮细胞密度(946～520mm-2)与术后3个月(920～499mm-2)比较,差异无统计学意义(P>0.05)。术后3d有2眼出现一过性高眼压,1周后恢复;术后1个月黄斑囊样水肿1眼,2个月后消失;术后3个月视力下降1眼,为视神经萎缩引起。术后随访期间未见角膜内皮失代偿、虹膜粘连、后囊膜破裂等严重并发症发生。结论抗青光眼小梁切除术后低角膜内皮细胞密度白内障患者行巩膜隧道小切口白内障摘出联合肝素修饰人工晶状体植入术是安全、有效的,但术前评估、手术技巧及术后处理是非常重要的。     

超声乳化白内障吸除术后角膜内皮细胞损伤和修复的临床观察

目的探讨超声乳化白内障吸除术后角膜内皮细胞损伤和修复的特点。方法对104例（104只眼）老年性白内障患者行超声乳化白内障吸除术,分别于术前、术后1周及1、2、3、6个月进行角膜内皮细胞密度和形态的观察和分析。结果角膜内皮细胞术前与术后1周、1个月、2个月细胞密度明显降低,差异有显著性,细胞形态明显增大,差异有显著性,角膜内皮细胞术前与术后3、6个月对比细胞密度下降不明显,差异没有显著性。细胞形态改变不大,差异没有显著性。结论超声乳化白内障吸除术后角膜内皮细胞最严重的损伤发生于术后2个月,在3个月时细胞的修复基本完成,术后半年以后细胞和形态基本恢复至术前的水平。