Posterior amorphous corneal dystrophy caused by a de novo deletion

We present a newborn diagnosed with posterior amorphous corneal dystrophy (PACD). PACD is a rare disorder with partial or complete posterior lamellar corneal opacification. Genetic screening showed a deletion of chromosome 12q21.33-q22 containing the identified four small leucine-rich proteoglycans (SLRP’s) associated with this particular dystrophy. Neither parents were carrier of the deletion. To our knowledge, this is the first report of a de novo mutation causing PACD.     

准分子激光原位角膜磨镶术后并发角膜瓣移位的原因分析及护理对策

原位角膜磨镶术(laser in situ kemtomileus,LASIK)是当今国际眼科界最常见的屈光角膜手术.随着LASIK手术越来越多地应用于临床,角膜瓣的并发症随之而来.文献报道[1],LASIK术后并发症发生率为3.4％～11.8％,而术中有关角膜瓣的发生率为0.5％～2％.角膜瓣一旦发生移位,会影响手术效果和视力恢复,须立即处理,否则后果严重[2].我们回顾性分析1 720例LASIK术后15例发生角膜瓣移位的患者资料,并对其护理策略进行探讨.     

Next-generation calcineurin inhibitors for ophthalmic indications

Calcineurin inhibitors (CNIs) are potent immunosuppressants that reversibly inhibit T-cell proliferation and prevent the release of pro-inflammatory cytokines by blocking the activity of calcineurin, a ubiquitous enzyme that is found in cell cytoplasm. CNIs can be highly effective in immune-mediated ophthalmic diseases such as uveitis, dry eye syndrome and inflammatory blepharitis, as well as for the prevention of rejection in corneal transplants. ISA-247/LX-211 is a novel CNI that is in Phase III clinical development for the treatment of various forms of non-infectious uveitis. ISA-247/LX-211 is a rationally designed analog of ciclosporin A that exhibits more predictable pharmacokinetic and pharmacodynamic properties and a 4-fold greater calcineurin inhibition than its parent compound, ciclosporin A. ISA-247/LX-211 has been observed to be effective, well-tolerated, and safe in early clinical trials, exhibiting a much wider therapeutic window compared with classic CNIs, such as ciclosporin A and tacrolimus. An alternative approach to widening the therapeutic window for the therapy of ophthalmic disorders lies in local delivery of CNIs through polymeric implants that release the drug over long periods of time. The silicone matrix episcleral implant LX-201 is in Phase III development at present for the prevention of rejection in high-risk cornea transplantation.     

弃瓣与留瓣LASEK治疗近视的临床疗效对比

目的分析比较弃瓣LASEK和留瓣LASEK治疗近视的临床疗效。方法采用自身对照法观察78例(156眼)接受LASEK的双眼近视患者,术中随机决定双眼中的一眼作为试验组,进行弃瓣处理,对侧眼则常规保留上皮瓣作为对照组,术后1d、3d、5d、10d,1周、2周、3周,1个月、2个月、3个月、4个月、6个月复查,复查项目包括角膜刺激症状、上皮愈合时间、裸眼视力、屈光度、Haze、眼压、Orbscan-Ⅱ角膜地形图等情况,并进行统计学处理。结果术后试验组角膜上皮愈合时间为(3.35±0.46)d,对照组为(4.47±0.68)d,差异有统计学意义(t=12.0486,P=0.000);术后第1天角膜刺激症状的评分试验组为0.96±0.61,对照组为1.47±0.58,差异有统计学意义(t=5.351,P=0.000);术后6个月内2组裸眼视力、屈光度及Haze的情况差异均无统计学意义(均为P>0.05);术后各时间点角膜地形图形态、SimK值及其差值2组比较,差异均无统计学意义(均为P>0.05);术后1个月时两组间角膜直径为3mm、5mm的Irreg值,差异均有统计学意义(均为P<0.05)。结论弃瓣LASEK治疗近视有很好的安全性、有效性和稳定性,且术后刺激症状轻、上皮愈合及视力恢复快。     

体外培养不同代角膜缘干细胞特性分析

目的比较不同代角膜缘干细胞的生物学特性,为角膜缘细胞移植在临床中的氉应用提供依据。方法组织块培养法体外培养角膜缘干细胞,光镜观察、HE染色和免疫荧光染色分析原代、第1代和第2代角膜缘细胞形态学特性;流式细胞技术定量检测原代、第1代和第2代角膜缘细胞ABCG2表达;MTT比色法测定体外培养原代、第1代和第2代角膜缘干细胞的增殖活性变化。结果倒置相差显微镜下可见原代细胞培养24h有单个细胞从组织块边缘迁出,48h细胞局部可见拉网样生长趋势,72h出现大片细胞,细胞呈现多边形或多角形,96h细胞几乎铺满整个培养板。随着传代次数的增加,细胞形态变得不规则,CK3单克隆抗体表达阳性率逐渐增强;p63单克隆抗体原代和第1代细胞间表达阳性率无明显差别,第2代细胞表达量明显减弱。流式细胞检测显示原代、第1代和第2代细胞ABCG2表达阳性率分别为13.41%、22.96%和4.43%。MTT结果显示随传代次数增加细胞增殖活性逐渐下降。结论原代和第1代角膜缘干细胞可以作为制备组织工程角膜上皮细胞膜片的较理想种子细胞。     

In Vivo Binding of Topically Applied Human bFGF on Rabbit Corneal Epithelial Wound

Abstract

We present the results of the first evaluation of human placenta extracted basic fibroblast growth factor (bFGF) in a rabbit corneal epithelium wound-healing model. Healing dose-response experiments after selective epithelial wounding with iodine vapors demonstrated that bFGF accelerated the repair process in a saturable manner. Corneal binding of topically applied ¹²⁵I-labeled bFGF was investigated using radioassay and autoradiographic techniques. Basic FGF was shown to bind specifically to denuded epithelial basement membrane in a very stable fashion and not to the intact epithelium. No transfer of the topical bFGF to the aqueous humor or any intraocular structure could be observed. The stability of this interaction was further demonstrated by reextracting and characterizing the labeled factor from treated corneas. The specificity of the fixation was documented by in vivo topical competition with unlabeled bFGF or heparin. We propose that bFGF-basement membrane interactions play a role in corneal wound healing.     

Genipin-crosslinked polyvinyl alcohol/silk fibroin/nano-hydroxyapatite hydrogel for fabrication of artificial cornea scaffolds—a novel approach to corneal tissue engineering

Abstract

Design of artificial corneal scaffolds substitute is crucial for replacement of impaired cornea. In this paper, porous polyvinyl alcohol/silk fibroin/nano-hydroxyapatite (PVA/SF/n-HA) composite hydrogel was prepared via the genipin (GP) cross-linking, the pore diameter of the hydrogel ranged from 8.138?nm and 90.269?nm, and the physical and physiological function of hydrogel were investigated. The resulting hydrogel exhibited favourable physical properties. With the GP content increasing, the structural regularity of PVA/SF/n-HA composite hydrogel was enhanced and the thermal stability was improved. The moisture content was slightly decreased and generally maintained at approximately 70%. The tensile strength was heightened up to 0.64?MPa, while the breaking elongation was decreased slightly. Moreover, the biofunction was investigated. The in vitro degradation test demonstrated that with the addition of GP, the stability of the composite hydrogels in protease XIV solution was promoted and the three-dimensional porosity structure of composite hydrogels was maintained as ever. And the human corneal fibroblasts (HCFs) were employed to examine the cells cytotoxicity of the PVA/SF/n-HA composite hydrogels with different GP content by CCK-8 assay. Based on confocal laser scanning microscope (CLSM) and scanning electron microscope (SEM), HCFs had individually commendable adhesion and proliferation on PVA/n-HA/SF composite hydrogel. HCFs proliferated and grew into the pores of composite hydrogel. The results of biocompatibility experiments of composite hydrogel suggested that it was no acute toxicity, in vitro cytotoxicity was 0 or 1 grade. Overall, results from this paper, PVA/n-HA/SF composite hydrogel was a qualified medical material which conformed to the national standard, could be a promising alternative for artificial cornea scaffold material—a novel approach to corneal tissue engineering.     

圆锥角膜基质环植入术的研究进展

角膜基质环植入术(ICRS)是一种用于治疗轻中度圆锥角膜的手术方法。ICRS是通过植入基质环,使中央角膜扁平化,弧长缩短,角膜曲率半径增大,屈光力降低,从而改善角膜前突导致的轴性近视眼与不规则散光。ICRS具有微创性、安全性、有效性、可逆性且并发症少等优点,其中长期疗效较佳。本文中笔者就ICRS的发展史、适应症、手术方法、手术疗效的影响因素、术后处理及疗效的评估等方面进行阐述。     

Techniques,indications and complications of corneal debridement

The cornea is the most exposed surface of the eye and, as such, is vulnerable to external trauma and the risk of infection. Many corneal diseases alter shape, surface, and transparency and thus result in reduced vision. The external position of the cornea, however, lends itself to diagnostic and therapeutic maneuvers that are commonly performed and readily done in the clinic. More sophisticated techniques require the use of complex equipment such as excimer and femtosecond laser. Complications that develop from poor healing and/or secondary infection are best avoided with appropriate technique, antisepsis, and modification of wound healing. We review corneal debridement in the management of corneal disease.