Clinical study of laminar resorption: Part 2- outcomes,review and proposal for classification

PurposeTo analyze and review the clinical features and main outcomes of laminar resorption from the UK osteo-odonto-keratoprosthesis (OOKP) cohort.MethodsA retrospective review of case records was undertaken for patients who underwent keratoprostheses between 1996 and 2014 at the Sussex Eye Hospital, Brighton, UK. The main clinical outcomes of resorption, including its clinical signs, complications, treatments, and laminar survival, were evaluated.ResultsSixty-four patients (25-females, 39-males) were included, and in total, 74 laminae (3-tibial, 11-allografts, 60-autografts) were implanted. The age of the patients ranged from 20 to 91 years. Focal laminar thinning was the first sign of detectable resorption in 50% of autografts and 27% of allografts. All the tibial grafts and 55% of allografts presented with complications of resorption like endophthalmitis and aqueous leakage as the first signs of resorption. The survival of first implanted autografts was 82.4%(±6.3%) at 18 years, which was enhanced to 91.5%(±5.0%) by prophylactic exchanges of critically resorbed laminae with new laminae. Visual acuity survival analysis did not reveal a statistically significant difference between grafts with and without resorption for all graft types (p = 0.825). Patients treated with Alendronic acid and acetazolamide demonstrated trends toward the slower progression of resorption, but this was not statistically significant.ConclusionsFocal laminar thinning was the common presenting feature of resorption in autografts. Timely replacement of the resorbed laminae with new laminae should be considered to avoid complications. Alendronic acid supplementation may be considered in high-risk cases of resorption to reduce further progression.     

多孔纳米羟基磷灰石-聚乙烯醇水凝胶人工角膜的实验研究

目的 评价多孔纳米羟基磷灰石-聚乙烯醇水凝胶(NHA-PAH)人工角膜在兔角膜内的生物学反应。方法 将NAH-PAHKPro加工成直径10．0mm，周边支架为2．5mm．中央光学部与裙袢连接部呈阶梯状，植入10只新西兰白兔角膜板层囊袋内。术后眼前段裂隙灯照相并分别于1月、2月、3月、4月、6月行术眼角膜组织病理学检查。结果 术后1个月大部分新生血管长入角膜中央，3月时新生血管生长达到高峰，术后6个月角膜中央存留大量变细的新生血管，未见人工角膜排出、基质融解、房水渗漏和感染。HE染色见术后1个月时成纤维细胞、新生血管及少量炎细胞长入裙袢孔隙内，伴有少量胶原形成。术后3个月所有孔隙均被胶原细胞和新生血管组织充填，成纤维细胞在孔隙内沿纵行方向一致性生长，胞头丰富，胞核小。中央光学部透明。结论 NHA-PAHKPro组织相容性好，具有临床应用的前景。     

相干光断层扫描在人工角膜术后眼底观察中的临床应用

目的探讨利用相干光断层扫描（OCT）观察人工角膜术后患者眼底黄斑的有效性。方法人工角膜术后患者7例（7只眼）,年龄30～76岁,平均39岁,矫正视力：5米光感至1.0,全部病例（7只眼）均行直接检眼镜、眼底彩色照相及OCT检查,分析比较这三种检查是否可清楚地观察到眼底黄斑部位。结果眼底彩色照相检查无法显示人工角膜眼的黄斑图像;直接检眼镜检查仅能观察到部分病例模糊的视盘图像,而黄斑不能窥清;OCT检查可获得清晰的人工角膜眼的黄斑图像。结论与眼底彩色照相、直接检眼镜检查相比,OCT可有效地直观显示人工角膜眼患者的黄斑情况,能够准确随诊,为观察人工角膜术后患者眼底变化提供了新的检查方法。     

人工角膜的研究进展

本文较详尽地介绍了人工角膜的研究进展,人工角膜的出现为那些由于所患角膜疾病不能应用穿透型角膜移植术或者缺乏条件而无法施行角膜移植术的患者带来了希望。自人工角膜诞生至今,人们在其材料和结构等方面进行着不断的研究,今后,人工角膜的研究重点是周边支架与受体组织的整合。