Woodward Maria A, Titus Michael, Mavin Kyle, Shtein Roni M
Department of Ophthalmology, University of Michigan, USA.
J Vis Exp. 2012 Jun 12(64):e3847. doi: 10.3791/3847.
Over the past ten years, corneal transplantation surgical techniques have undergone revolutionary changes. Since its inception, traditional full thickness corneal transplantation has been the treatment to restore sight in those limited by corneal disease. Some disadvantages to this approach include a high degree of post-operative astigmatism, lack of predictable refractive outcome, and disturbance to the ocular surface. The development of Descemet's stripping endothelial keratoplasty (DSEK), transplanting only the posterior corneal stroma, Descemet's membrane, and endothelium, has dramatically changed treatment of corneal endothelial disease. DSEK is performed through a smaller incision; this technique avoids 'open sky' surgery with its risk of hemorrhage or expulsion, decreases the incidence of postoperative wound dehiscence, reduces unpredictable refractive outcomes, and may decrease the rate of transplant rejection. Initially, cornea donor posterior lamellar dissection for DSEK was performed manually resulting in variable graft thickness and damage to the delicate corneal endothelial tissue during tissue processing. Automated lamellar dissection (Descemet's stripping automated endothelial keratoplasty, DSAEK) was developed to address these issues. Automated dissection utilizes the same technology as LASIK corneal flap creation with a mechanical microkeratome blade that helps to create uniform and thin tissue grafts for DSAEK surgery with minimal corneal endothelial cell loss in tissue processing. Eye banks have been providing full thickness corneas for surgical transplantation for many years. In 2006, eye banks began to develop methodologies for supplying precut corneal tissue for endothelial keratoplasty. With the input of corneal surgeons, eye banks have developed thorough protocols to safely and effectively prepare posterior lamellar tissue for DSAEK surgery. This can be performed preoperatively at the eye bank. Research shows no significant difference in terms of the quality of the tissue or patient outcomes using eye bank precut tissue versus surgeon-prepared tissue for DSAEK surgery. For most corneal surgeons, the availability of precut DSAEK corneal tissue saves time and money, and reduces the stress of performing the donor corneal dissection in the operating room. In part because of the ability of the eye banks to provide high quality posterior lamellar corneal in a timely manner, DSAEK has become the standard of care for surgical management of corneal endothelial disease. The procedure that we are describing is the preparation of the posterior lamellar cornea at the eye bank for transplantation in DSAEK surgery (Figure 1).
在过去十年中，角膜移植手术技术经历了革命性的变革。自传统全层角膜移植术问世以来，它一直是治疗因角膜疾病而视力受限患者的方法。这种方法的一些缺点包括术后散光程度高、屈光结果不可预测以及眼表受到干扰。仅移植角膜后基质、Descemet膜和内皮的Descemet膜剥脱内皮角膜移植术（DSEK）的发展，极大地改变了角膜内皮疾病的治疗方式。DSEK通过较小的切口进行；该技术避免了有出血或排斥风险的“开放式”手术，降低了术后伤口裂开的发生率，减少了不可预测的屈光结果，并可能降低移植排斥率。最初，用于DSEK的角膜供体后板层剥离是手动进行的，这导致移植物厚度不一，并且在组织处理过程中对脆弱的角膜内皮组织造成损伤。为了解决这些问题，开发了自动板层剥离术（Descemet膜剥脱自动内皮角膜移植术，DSAEK）。自动剥离术利用与准分子激光原位角膜磨镶术（LASIK）制作角膜瓣相同的技术，使用机械微型角膜刀刀片，有助于为DSAEK手术制作均匀且薄的组织移植物，在组织处理过程中使角膜内皮细胞损失最小化。多年来，眼库一直在为手术移植提供全层角膜。2006年，眼库开始开发为内皮角膜移植术提供预切割角膜组织的方法。在角膜外科医生的参与下，眼库制定了完善的方案，以安全有效地为DSAEK手术准备后板层组织。这可以在术前在眼库进行。研究表明，在DSAEK手术中，使用眼库预切割组织与外科医生准备的组织相比，在组织质量或患者预后方面没有显著差异。对于大多数角膜外科医生来说，可获得预切割的DSAEK角膜组织节省了时间和金钱，并减轻了在手术室进行供体角膜剥离的压力。部分由于眼库能够及时提供高质量的后板层角膜，DSAEK已成为角膜内皮疾病手术治疗的标准方法。我们正在描述的程序是在眼库为DSAEK手术准备后板层角膜以供移植（图1）。
