Bayoudh Wesal, Carstesen Dörthe, Walter Peter, Weinberger Andreas W A
Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
Department of Ophthalmology, Klinikum Dortmund gGmbH, Beurhausstraße 40, 44137, Dortmund, Germany.
Graefes Arch Clin Exp Ophthalmol. 2017 Oct;255(10):1947-1955. doi: 10.1007/s00417-017-3714-x. Epub 2017 Jul 3.
The management of chronic ocular hypotony and complicated proliferative vitreoretinopathy-related retinal detachment represents a challenge. Being non-absorbable and non-biodegradable, a silicone oil implant is expected to restore the volume and the intraocular pressure of the globe, as well as to approximate the detached retina. Further advantages could be a long-term tamponade potential, absence of toxicity, and prevention of silicone oil emulsification or anterior chamber oil-prolapse. The aim of this study was to assess the histological tolerance of the silicone oil implant in a pig model.
A seamless silicone balloon implant with optional surface modifications was developed. Mini pigs were used as experimental animals, and three variants of silicone implants with different surfaces were tested: uncoated, NCO-sP(EO-stat-PO) coated, and heparin-NCO-sP(EO-stat-PO) coated silicone implants. An extracapsular lens extraction was achieved via a standard phacoemulsification followed by a standard three-port vitrectomy. The implant was then placed in the posterior segment and filled with 5000 centistoke silicone oil. One month later, the pigs were euthanized, the eyes were enucleated, and histological specimens were prepared for microscopy.
The analysis of the histology revealed that adverse histological changes in conjunctiva, cornea, iris, and ciliary body could be excluded in all eyes operated on regardless of which variant of implant had been employed. The retina as the implant-contacting ocular tissue showed overall good tolerance, although some inflammatory reaction and fibrous proliferation was evident in some cases.
The silicone oil implant is a promising candidate and has the potential to fulfill clinical requirements to act as a long-term intraocular tamponade agent. The heparin-NCO-sP(EO-stat-PO) coating approach could lead to a novel bioactive surface for intraocular devices with excellent properties to hinder cell adhesion and protein adsorption, although further studies will be necessary to evaluate long-term biocompatibility and long-term resistance to biological attacks.
慢性低眼压以及与增生性玻璃体视网膜病变相关的复杂性视网膜脱离的治疗颇具挑战。硅油植入物不可吸收且不可生物降解，有望恢复眼球的容积和眼压，使脱离的视网膜复位。其进一步的优势可能包括长期的填塞潜能、无毒性以及预防硅油乳化或前房硅油脱垂。本研究旨在评估猪模型中硅油植入物的组织学耐受性。
研发了一种具有可选表面修饰的无缝硅胶球囊植入物。小型猪用作实验动物，测试了三种具有不同表面的硅胶植入物变体：未涂层、NCO-sP(EO-stat-PO)涂层以及肝素-NCO-sP(EO-stat-PO)涂层的硅胶植入物。通过标准的超声乳化白内障吸除术，随后进行标准的三通道玻璃体切除术，实现囊外晶状体摘除。然后将植入物置于眼后段并填充5000厘沲的硅油。一个月后，对猪实施安乐死，摘除眼球，并制备组织学标本用于显微镜检查。
组织学分析显示，无论采用哪种植入物变体，所有接受手术的眼睛均可排除结膜、角膜、虹膜和睫状体的不良组织学变化。作为与植入物接触的眼组织，视网膜总体耐受性良好，尽管在某些情况下可见一些炎症反应和纤维增生。
硅油植入物是一个有前景的选择，有潜力满足作为长期眼内填塞剂的临床需求。肝素-NCO-sP(EO-stat-PO)涂层方法可能会为眼内装置带来一种具有优异性能以阻碍细胞黏附和蛋白质吸附的新型生物活性表面，不过仍需进一步研究来评估其长期生物相容性和对生物攻击的长期抵抗力。
