Banded structures in collagen vitrigels for corneal injury repair

There is a growing interest in using collagen vitrigels for corneal injury repair. We recently reported the synthesis and thermal denaturation behavior of these gels. In this paper, the banded structure in these vitrified gels is studied by small-angle X-ray scattering (SAXS) one-dimensional (1-D) correlation function analysis and transmission electron microscopy (TEM). Results demonstrate that the collagen vitrigel possess banded structures similar to those of the starting type I collagen, with an average D-spacing of 64 nm (by SAXS) or 57 nm (by TEM). A combination of SAXS 1-D correlation function analyses and TEM show that overlap and gap distances ranged from 30 to 33 nm and from 23 to 25 nm, respectively. Changing the vitrification condition does not impact on the banded structure significantly.     

Collateral damage: Corneal injury due to mask use during the COVID-19 pandemic - A case series

Though masks are the best shield against COVID-19, they can be a source of discomfort and ocular side effects. We discuss three cases of corneal injury due to mask use. Three patients, who were healthcare workers, presented with discomfort, photophobia, and pain in the eyes. While adjusting the mask, they had an ocular injury. There were multiple superficial linear abrasions in the eyes. They recovered with treatment. Though masks are imperative during the COVID-19 pandemic, it is important to be aware of a possible mask injury.     

角膜异物伤高发人群的预防干预(附角膜异物剔除术132例)

目的 分析角膜异物伤患者诊治情况,了解其流行病学特点,探讨角膜异物伤高发人群的预防干预.方法 回顾性分析132例(132眼)于我院南院门诊就诊角膜异物伤患者的就诊时间、病因、检查、治疗及复诊治疗情况.结果 城乡结合部是角膜异物伤发生的高发区,132例患者年龄5～58岁,均为男性,绝大多数为青壮年,79.7%角膜异物性质为铁屑,五金加工、装修工人者占发病者的64.6%.就诊患者健康意识较差,54.9%患者进行角膜异物剔除术后未进行复诊.结论 角膜异物伤是非常常见的眼外伤,年轻男性、特别是外来民工等在工作中需操作冲击力工具的工人是该病的高危人群,健康意识及治疗依从性差影响治疗情况.     

环曲面和球形角膜塑形镜在散光患者中的疗效分析

目的 比较环曲面和球形角膜塑形镜在中高度散光患者治疗中的疗效。方法 回顾性分析2019年6月至2020年9月安徽省第二人民医院眼科佩戴角膜塑形镜片的77名近视合并中、高度散光(≥1.0 D)患者的临床资料。根据受试者选择透镜设计不同分为环曲面组(n=36)和球形组(n=41)。观察两组患者1年内佩镜的治疗效果,评价指标为裸眼视力(UCVA)、镜片偏心度及角膜散光J0、J45。结果 环曲面及球形组UCVA分别从佩戴前的0.80(0.60, 0.10)、0.80(0.55, 0.90)下降到佩戴12个月后的0(0.00, 0.08)、0(0.00, 0.10),两组佩戴前后各时间点比较,差异无统计学意义(P>0.05)。环曲面组及球形组镜片偏心度由戴镜1天的(0.46±0.25)mm、(0.53±0.21)mm增加至戴镜12个月的(0.73±0.41)mm、(1.32±0.12)mm,角膜散光J0分别由基线时的(-0.59±0.73)D、(-0.78±0.41)D下降到佩戴12个月的(-0.13±0.68)D、(-0.69±1.19)D,两组患者佩戴1个月后偏心度和角膜散光J0比较,...     

Clinical Outcomes of Nanothin Descemet Stripping Automated Endothelial Keratoplasty in Korean Patients with Corneal Endothelial Dysfunction

PurposeTo evaluate the clinical outcomes of nanothin Descemet stripping automated endothelial keratoplasty (DSAEK) in Korean patients with corneal endothelial dysfunction.MethodsWe retrospectively reviewed medical records of the patients who underwent nanothin DSAEK (graft thickness ≤50 μm) due to corneal endothelial dysfunction and followed up more than 1 year. We evaluated best-corrected visual acuity (BCVA), central corneal thickness, and corneal endothelial cell density at preoperative and 1, 3, 6, and 12 months postoperatively.ResultsSixteen eyes of 16 patients with the mean follow-up period of 13.00 ± 0.96 months were included. The mean graft thickness after deswelling was 45.25 ± 4.59 μm (range, 38.0–50.0 μm). The mean logarithm of the minimum angle of resolution BCVA improved from 1.37 ± 0.53 preoperatively to 0.68 ± 0.46, 0.55 ± 0.35, 0.40 ± 0.25, and 0.39 ± 0.25 at 1, 3, 6, and 12 months postoperatively (p = 0.005, p < 0.001, p < 0.001, and p < 0.001), respectively. The mean central corneal thickness improved from 752.00 ± 129.11 to 555.75 ± 54.66 μm at 12 months postoperatively (p = 0.006). The mean graft endothelial cell density decreased from 2,859.62 ± 228.34 to 1,542.25 ± 627.34 cells/mm² at 12 months postoperatively (p = 0.012). The postoperative complications included increased intraocular pressure (n = 3, 18.75%) and graft dislocation (n = 1, 6.25%), all of which were successfully managed by anterior chamber paracentesis or rebubbling. No other serious complications were encountered.ConclusionsNanothin DSAEK produced significant and stable visual improvements without severe postoperative complications in Korean patients with corneal endothelial dysfunction.     

角膜后弹力膜内皮移植术研究进展

角膜后弹力膜内皮移植术由于具有相对较低的移植排斥率以及较好的视力预后等优势,目前已成为部分发达国家治疗角膜内皮失代偿的主流手术方式,但限于手术难度较高,学习曲线较长,中国人前房偏浅,加之国内角膜内皮病变往往合并有其他较复杂的眼部疾病,目前国内尚未普遍开展这一手术。本文就角膜后弹力膜内皮移植术的手术适应证、供体植片制备(...     

Mitomycin C application after photorefractive keratectomy in high,moderate, or low myopia: Systematic review and meta-analysis

Photorefractive keratectomy (PRK) is considered a safe approach laser procedure with a clinical significance in correcting myopia results. PRK requires removing the whole superficial epithelium. The integrity of the epithelial basement membrane and the deposition of abnormal extracellular matrix can put the cornea in a probable situation for corneal haze formation. Mitomycin C (MMC) is applied after excimer laser ablation as a primary modulator for wound healing, limiting corneal haze formation. We aim to summarize the outcomes of MMC application after laser ablation. We searched Scopus, PubMed, Cochrane CENTRAL, and Web of Science till December 2020 using relevant keywords. The data were extracted and pooled as mean difference (MD) or risk ratio (RR) with a 95% confidence interval (CI), using Review Manager software (version 5.4). Our analysis demonstrated a statistically significant result for MMC application over the control group in terms of corneal haze formation postoperatively (RR = 0.29, 95% CI: [0.19, 0.45], P < 0.00001). Regarding corrected distance visual acuity (CDVA), no significant difference was observed between the MMC group and the control group (MD = 0.02; 95% CI: [-0.04, 0.07]; P = 0.56). Regarding the uncorrected distance visual acuity (UDVA), the analysis favored the MMC application with (MD -0.03, 95% CI: [-0.06, -0.00]; P = 0.05). There was no statistically significant increase in complications with MMC. In conclusion, MMC application after PRK is associated with a lower incidence of corneal haze formation with no statistically significant side effects. The long term effect can show improvement regarding UDVA favoring MMC. However, there is no significant effect of MMCs application regarding CDVA, and SE.     

纤维蛋白粘合剂与人角膜成纤维细胞的生物相容性

目的:探讨纤维蛋白粘合剂(FS)与全飞秒激光小切口透镜取出术(SMILE)来源的人角膜成纤维细胞(HCFs)的生物相容性。方法:人角膜组织取自2018年3—4月于广西医科大学第一附属医院行SMILE患者12例24眼术中取出的角膜基质透镜,体外分离培养HCFs,观察HCFs在FS表面的生长状态。将HCFs分为2倍浸提液组...     

FS-LASIK与SMILE术后角膜上皮重塑的比较

目的观察飞秒激光制瓣联合准分子激光原位角膜磨镶术(femtosecond laser in situ keratomileusis,FS-LASIK)与飞秒激光小切口角膜基质透镜取出术(small incision lenticular extraction,SMILE)术后角膜上皮重塑的特征。方法按照手术方式分为两组,FS-LASIK组29例(58眼),SMILE组31例(61眼),年龄(26±6.5)岁,术前等效球镜度数为(-5.25±2)D,分别于术前,术后1个月、3个月及6个月应用眼前节OCT对患者角膜中央2 mm、2~5 mm上皮厚度进行测量。结果术后1个月FS-LAISK组角膜中央2 mm与角膜2~5 mm范围内的平均角膜上皮增厚差异存在统计学意义(P=0.036);术后3个月2~5 mm范围,角膜上皮在上方、鼻上方、颞上方与下方、颞下方、鼻下方相比,增厚更轻微,差异均有统计学意义(P=0.042,P=0.031,P=0.049);术后6个月SMILE组角膜中央2 mm、角膜2~5 mm的角膜上皮增厚差异存在统计学意义(P=0.047),2~5 mm范围内,角膜上皮在上方、鼻上方、颞上方与下方、颞下方、鼻下方相比,增厚更轻微,差异均有统计学意义(P=0.012,P=0.035,P=0.009),上方与鼻侧、颞侧相比,增厚更少,差异有统计学意义(P=0.045,P=0.017);FS-LASIK组,术后1至6个月角膜上皮增厚在0~2 mm内逐渐下降,差异有统计学意义(P=0.035);术后各个时间段中,FS-LASIK组与SMILE组角膜上皮厚度在0~5 mm范围内各个位点差异均有统计学意义(P<0.05)。结论FS-LASIK术后角膜上皮增厚较SMILE术后更加明显。FS-LASIK术后角膜上皮增厚在角膜切削中央区域变化更加明显,SMILE术后角膜上皮增厚在角膜切除周边区域变化更加明显。随着时间推移,两种手术术后均出现与切口位置相反的角膜上皮局部继续增厚的表现。     

以猪角膜脱细胞基质为载体培养人脐静脉内皮细胞构建实验性角膜后板层

 目的： 探讨以异种后弹力膜/基质为载体诱导人脐静脉内皮细胞向角膜内皮细胞分化的可行性及移植术后在活体的生理功能。方法：体外分离培养脐静脉内皮细胞作为诱导移植的种子细胞;取当地质检合格的猪眼球以直径6.2 mm、厚100 μm、冷冻脱水进行角膜深板层载体的制备;接种经CM-DiI荧光标记的第2~3代人脐静脉内皮细胞于载体的后弹力层面,体外培养7~10 d行细胞形态、密度、组织学和扫描电镜观察,待细胞与后弹力层面融合形成单层后,用于兔角膜移植。受眼：正常健康新西兰大白兔24只（24眼）,实验组（人脐静脉内皮细胞移植组）12眼,对照组（单纯猪角膜深板层移植组）12眼,全角膜范围去除术眼内皮细胞,实施移植手术。结果：人脐静脉内皮细胞在猪后弹力膜/基质载体上贴附生长,形成紧密连接的单层,形态近似六角形,呈铺路石状分布,具有正常兔角膜内皮细胞的超微结构。术后8周实验组角膜基本透明,周边角膜略有水肿。对照组单纯猪角膜深板层移植后,移植角膜明显水肿、混浊。结论：以异种角膜后弹力膜/基质为载体培养的人脐静脉内皮细胞,行异种异体移植后,能够在活体上成活,并能维持角膜透明,具有正常角膜内皮细胞的生物学功能。深板层角膜内皮移植术是体外培养血管内皮细胞移植的一种有效术式。