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(...     

角膜内皮板层移植术治疗角膜内皮病变的初步报告

探讨角膜内皮板层移植术 (endotheliallamellarkeratoplasty ,ELK)治疗角膜内皮病变的临床效果。方法 :对 6例 ( 6眼 )因角膜内皮病变导致的角膜水肿、混浊患者施行了ELK术。其中 ,白内障术后大泡性角膜病变 2例 ,Fuchs角膜内皮营养不良 1例、外伤性角膜内皮失代偿 3例。用 6 0～ 7 5mm环钻切取前 1/ 2厚度供眼板层角膜片 ,保留后 1/ 2厚度 ,包括后基质、后弹力层和内皮细胞层的后板层角膜片。用比供体角膜片小 0 2 5～ 0 5mm的环钻钻切患眼角膜 ,深度达 1/2厚度 ,用角膜板层刀剖切下前板层备用 ,再钻切后板层角膜。将异体后基质角膜植片和自体前基质角膜植片重叠用 10 / 0尼龙线连续缝合。术毕结膜下注射庆大霉素和地塞米松 ,术后局部滴环孢霉素。随访 6～ 15个月。结果 :植片平均上皮化时间 6 5天 ,无新生血管侵入异体后基质植片 ,5例植片透明 ,1例排斥反应。裸眼视力 0 0 8～ 0 3 ,1例因白内障需进行手术 ,2例分别因原有的青光眼和老年性黄斑变性而视力不能矫正 ,1例层间积液 (粘弹剂 )经冲洗而消失。结论 :ELK具有植片上皮化时间短、水肿消失快、手术反应轻、排异反应率低等特点 ,对治疗内皮失代偿的病变是一种较理想的替代手术。     

后弹力层角膜内皮移植术应用与手术技术

角膜内皮移植(endothelial keratoplasty,EK)是针对内皮细胞功能障碍的靶向性治疗方法.目前已成为国际上治疗角膜内皮病变的首选方法.而后弹力层角膜内皮移植术(Descemet's membrane endothelial keratoplasty,DMEK)是目前EK最新技术,也称为小切口角膜内皮移植术,从解剖学角度完美恢复了角膜组织的正常结构,可更好更快恢复视力,且术后排斥反应显著降低,受到了广泛关注和认可.然而,DMEK作为一项新技术,虽然具有显著的优点,也面临着技术上的挑战.最受关注的是供体制备过程中内皮片的丢失、植入受体的展开和位置调整.目前随着手术方法和设备的不断改进,植入技术不断改进,学习曲线正在逐渐减低,越来越多的眼科医生掌握了该技术.由于角膜材料与手术适应证等限制,目前我国尚无开展DMEK的报道.     

穿透性角膜移植治疗外伤性角膜病变的临床观察

目的:探讨穿透性角膜移植术治疗外伤性角膜病变的临床疗效。方法:对17例外伤性角膜病变施行穿透性角膜移植术,2例行穿透性角膜移植术联合小梁切除术,观察术后角膜植片及视力变化。结果:随访6~18(平均11.2)mo,术后临床症状明显缓解或消失,植片透明率为84%。视力较术前提高,其中矫正视力0.05以上16例;术后继发性青光眼5例,内皮型排斥反应4例。结论:穿透性角膜移植术是治疗外伤性角膜病变的一种有效的手术方式,其主要并发症为继发性青光眼和角膜移植排斥反应。     

不剥除后弹力层的深板层角膜内皮移植术治疗大泡性角膜病变的初步临床观察

目的 探讨不剥除后弹力层的深板层角膜内皮移植术治疗大泡性角膜病变的可行性和临床疗效.方法 前瞻性系列病例研究,收集自2007年9月至2009年1月在我院住院的大泡性角膜病变患者,进行不剥除后弹力层的深板层角膜内皮移植术.术中均未处理患眼角膜内皮.直接用植入镊将制作好的直径为8.5mm的角膜内皮植片植入受体前房,气体顶压植片进行固定.术后随访6～20个月,观察植片贴附和植片移位等情况,对手术前后的视力进行比较,检查植片透明度和角膜内皮细胞密度.结果 5例患者术后植片与受体内皮面始终贴附良好;1例患者术后第2天出现层间裂隙,经改俯卧位后植片贴附良好.6例患者植片均透明,其中5例患者术后最佳矫正视力均有不同程度的提高;1例患者术后视力同术前,视力不提高的原因为眼外伤造成的视神经萎缩.6例术后平均角膜内皮细胞密度为(1648±384)个/mm~2.随访过程均未发现有免疫排斥反应发生.结论 不剥除后弹力层的深板层角膜内皮移植术治疗大泡性角膜病变具有安全、有效、操作简便等特点,有望成为治疗该病的手术方式之一.     

后板层角膜内皮移植术

后板层角膜内皮移植术是近年来出现的治疗角膜内皮病变的技术，用于Fuchs角膜营养不良及无晶状体眼、人工晶状体眼并发的大泡性角膜病变。与传统的穿透性角膜移植相比具有手术时间短、风险小、术后较少出现高度散光、视力恢复快、宿主对植片的排斥反应少、切口裂开的可能性小等优点。此技术可使来源紧张的角膜组织得到充分利用，代表了一种新的可能取代穿透性角膜移植术治疗角膜内皮病变的方法。     

角膜后弹力层剥除自动角膜刀取材内皮移植手术的方法和体会

角膜后弹力层剥除自动角膜刀取材内皮移植术(DSAEK)已经成为替代穿透性角膜移植治疗角膜内皮病变的首选术式,其优点为仅去除病变的角膜内皮和后弹力层,最大限度地保持角膜的完整性,避免眼表面的损伤和明显的屈光变化.手术方法为在角膜缘部制备5 mm的隧道切口,用后弹力膜剥离钩划开并剥除病变的角膜后弹力层和内皮层,同时移植带有部分角膜后基质的后弹力层和内皮层,经前房注气展开并顶起植片使之与植床贴附,无缝线,避免了角膜散光.手术中及术后重要的环节和经验是:亚洲人的前房较浅,在植片植入和展开的环节会有一些问题,因此术前要充分降低眼压,防止术中晶状体虹膜隔的前移,使前房内有较充足的空间植入植片;手术后植片脱位是DSAEK的最大并发症,往往也是导致手术失败的主要原因,避免的方法为术中尽量减少黏弹剂的应用,在植片植入前将前房内的黏弹剂彻底冲洗干净,在植片与植床贴附后要尽量排除二者之间的液体,增加二者的贴附力.晶状体虹膜隔的完整性与气泡能否在前房内持续保持有密切的关系,如果晶状体虹膜隔不完整,气泡容易进入玻璃体腔,无法顶住植片,容易导致植片的脱位,因此早期在手术适应证的选择上要注意这些方面的问题.     

后板层角膜内皮移植术

后板层角膜内皮移植术是近年来出现的治疗角膜内皮病变的技术,用于FuchS角膜营养不良及无晶状体眼、人工晶状体眼并发的大泡性角膜病变。与传统的穿透性角膜移植相比具有手术时间短、风险小、术后较少出现高度散光、视力恢复快、宿主对植片的排斥反应少、切口裂开的可能性小等优点。此技术可使来源紧张的角膜组织得到充分利用,代表了一种新的可能取代穿透性角膜移植术治疗角膜内皮病变的方法。     

自动板层刀辅助的后弹力层前膜角膜内皮移植术

角膜内皮移植已成为治疗角膜内皮病变的首选方法.作为目前主流的2种角膜内皮移植手术——后弹力层剥除自动板层刀制备的角膜内皮移植术和后弹力层角膜内皮移植术,前者手术操作易于掌握,但角膜植片仍带有部分基质;后者术后视觉质量好,但手术操作较难掌握,二次手术率较前者高.大气泡和自动板层刀辅助的后弹力层前膜角膜内皮移植术在自动板层刀制备角膜内皮植片的基础上,用大气泡法暴露中央6.5 mm直径的后弹力层前膜,本术式既有后弹力层角膜内皮移植术后的视觉效果,手术操作又易于掌握,值得推广.     

角膜生物力学及其在临床中的应用

角膜作为人体重要的软组织之一,具有典型的黏弹性材料特性,它占眼球总屈光率的70%,其力学特性对于屈光手术、角膜营养不良病变及眼压的测量有着重要意义.本文从角膜显微结构出发,介绍角膜的生物力学特性及其在圆锥角膜、Fuchs角膜内皮营养不良等角膜病变中的变化.对角膜力学特性与眼压的相关性、现代屈光手术中涉及的角膜生物力学特性和白内障、玻璃体手术引起的角膜力学特性的改变做简要介绍,同时对目前测量和改善角膜生物力学特性的手段及方法作一综述.     

正确选择角膜内皮移植的适应证

角膜内皮移植具有许多独特的优点,有望取代穿透性角膜移植成为治疗角膜内皮失代偿的首选术式.然而,内皮移植也存在术后内皮细胞密度偏低的缺陷,而且,我国的大泡性角膜病变主要见于白内障等眼内手术造成的角膜内皮损伤,病情严重且伴多种眼内异常,使角膜内皮移植面临较大的困难,术后内皮细胞密度下降更明显.根据患者的病情特点,选择合适的术式和适应证是保证手术成功的关键.采用一些改良技术也能减轻内皮细胞的损伤,提高手术成功率.     

迎接角膜移植手术发展的新阶段

穿透性角膜移植已经不是角膜手术的唯一标准和手段,成分移植的理念带来了手术方式的新突破,由此涌现出的深板层移植、内皮移植等显著降低了术后的排斥反应等并发症,提高了视觉质量和供体角膜的利用度。飞秒激光的应用将角膜移植手术带入了屈光手术时代。角膜胶原交联技术的出现,丰富了医生的治疗手段,使圆锥角膜等角膜疾病大幅度摆脱了对角膜移植手术的依赖。这一系列进步使角膜移植手术进入了精准医疗的范畴。     

Endothelial keratoplasty – a review

From its inception over a century ago, penetrating keratoplasty grew to become the most common and most successful form of solid tissue transplantation. Yet clinicians have long recognized the limitations of full‐thickness corneal transplants, including prolonged visual rehabilitation, unpredictable refractive changes, susceptibility to ocular surface complications and vulnerability to traumatic wound rupture. Selective replacement of diseased or damaged posterior corneal layers was conceptualized and implemented a half century ago. However, it has only been within the past decade that improved techniques and instrumentation have allowed endothelial keratoplasty (EK) to become the preferred treatment for patients with endothelial dysfunction. EK provides more rapid visual recovery, minimizes induced astigmatism and, most importantly, better maintains globe integrity than penetrating keratoplasty. Descemet stripping automated EK is currently the most widely used method. This article covers how EK techniques have evolved over time, considers who is or is not an appropriate candidate for EK, describes Descemet stripping automated EK methods and instrumentation, discusses EK postoperative complications and management and compares visual recovery, refractive outcomes and endothelial cell loss with that of standard penetrating keratoplasty.     

Endothelial keratoplasty: a revolution in evolution

Endothelial keratoplasty (EK) is continually evolving both in surgical technique and clinical outcomes. Descemet's stripping endothelial keratoplasty (DSEK) has replaced penetrating keratoplasty (PK) as the treatment of choice for corneal endothelial dysfunction. It is safe and predictable and offers early visual rehabilitation. Newer iterations include Descemet's membrane endothelial keratoplasty, Descemet's membrane automated endothelial keratoplasty, and other hybrid techniques. Early data on these newer EK techniques suggests that they provide significantly better visual outcomes compared to DSEK. Initial 5-year survival data indicates that EK is at least comparable to PK, and more widespread survival data is anticipated. Further work is needed to simultaneously optimize visual outcomes, refractive predictability, and endothelial cell survival, as well as surgical techniques of donor preparation and insertion.     

组织工程角膜研究和应用进展

中国角膜供体材料的严重缺乏导致众多的角膜盲患者不能通过角膜移植来复明仍是临床棘手的问题。近年来,细胞生物学、组织工程学和材料学的发展为替代人角膜材料开辟了更广阔的前景;而且以深板层移植和内皮移植为代表的成分板层移植的推陈出新从临床技术上有力地推动了组织工程角膜的研发。现就脱细胞角膜基质板层材料、上皮细胞和内皮细胞组织工程的基础研究和临床应用进展进行述评。     

Corneal transplant rejection rate and severity after endothelial keratoplasty

PURPOSE: To examine the corneal transplant rejection rate and the rate of graft failure subsequent to rejection in the first 2 years after endothelial keratoplasty (EK) and to compare this to background data for similar cases of penetrating keratoplasty (PK). METHODS: Anonymized data from consecutive cases of EK [deep lamellar (DLEK) or Descemet stripping (DSEK)] for Fuchs corneal endothelial dystrophy or pseudophakic bullous keratopathy operated on before August 2004 were collected in 4 participating centers. The number and timing of rejection episodes and cases of subsequent graft failure were recorded, together with the time to cessation of topical steroid medication. Two-year postoperative findings were compared with background data for similar patients undergoing PK recorded in the Swedish Corneal Transplant Registry. RESULTS: Rejection episodes were less frequent after EK than PK (P = 0.035). Fifteen (7.5%) of 199 EK cases had a rejection episode in the first 2 years after surgery versus 92 (13%) of 708 PK cases. Graft failure after rejection in EK may have been less frequent than in PK (P = 0.063), with only 1 (6.7%) case of rejection after EK versus 26 (28.3%) cases of rejection after PK proceeding to graft failure. A strong trend toward continued use of low-dose topical steroid medication was observed in the EK group. Eighty percent of EK patients were still taking topical steroid medication 2 years after surgery, whereas topical steroid medication had been ceased within a year of surgery in almost all PK patients in the comparator group. CONCLUSIONS: Corneal transplant rejection is less frequent and may be less severe after EK than after PK. It is not yet clear whether these apparent differences are simply a product of relatively prolonged postoperative topical steroid cover in EK patients.     

前房冲洗在严重前房积脓性角膜溃疡的角膜移植术中应用

目的 探讨感染性角膜溃疡伴有大量前房积脓患者于角膜移植术前行前房冲洗的临床意义.方法 回顾性系列病例研究.2008年1月至2009年6月于山东省眼科医院接受手术的角膜溃疡伴有严重前房积脓的患者20例(20只眼),前房积脓均超过3 mm,其中13例患者伴有明显的角膜内皮斑,术前裂隙灯显微镜下病灶边缘难于判断.对20例患者采用前房穿刺冲洗联合穿透或板层角膜移植手术治疗.供体采用角膜中期保存液保存或甘油干燥冷冻保存.对术中与术后并发症、视力、免疫排斥反应等进行观察,随访时间术后6～12个月.结果 20例患者均成功行前房穿刺冲洗联合角膜移植手术,其中11只眼行穿透性角膜移植,9只眼行板层角膜移植.10例接受穿透性角膜移植的患者采用角膜中期保存液保存的供体角膜,其余10例患者采用甘油脱水冷冻保存的供体角膜.术中并发症主要为虹膜出血(11例),术后并发症主要包括部分虹膜后粘连(8例)、一过性眼压高(4例)、前房积血(5例),药物治疗均缓解.真菌复发1例,行扩大病灶切除再次穿透性角膜移植手术后感染控制.4例患者发生内皮型免疫排斥反应,3例抗排斥治疗后控制,1例发生植片混浊.至2009年12月最后随访,9例接受角膜中期保存液保存角膜供体患者的植片透明,1例植片水肿混浊;8例接受甘油脱水冷冻保存角膜供体患者的植片透明,2例植片水肿.结论 常规角膜移植前行前房穿刺冲洗,对严重前房积脓性角膜溃疡病灶边缘的判断和手术方式选择具有重要意义,可以提高手术的安全性.     

Evidence-Based Endothelial Rehabilitation

ABSTRACT

Endothelial keratoplasty (EK) has replaced penetrating keratoplasty (PKP) as the preferred surgical therapy for corneal endothelial dysfunction. However, recent nationwide corneal graft registry data showed few advantages to EK relative to PKP with respect to graft survival and visual outcomes. This article compares the published outcomes and complications of EK to those of PKP. EK demonstrates superior spectacle corrected visual outcomes, fast recovery, less graft rejection, and higher patient satisfaction, particularly in studies performed by high-volume surgeons/centers. Endothelial cell loss in EK, while higher at early time points, was equivalent or superior at five-years’ follow-up and graft survival was equivalent to or superior to PKP in these centers/studies. Continued standardization and simplification of EK procedures may allow surgeons who perform a lower volume of EK to achieve results that mirror those of high-volume centers/surgeons and close the potential gap in outcomes demonstrated in the registry data.