Taban Mehran, Rao Bin, Reznik Jacob, Zhang Jun, Chen Zhongping, McDonnell Peter J
Department of Ophthalmology, University of California-Irvine, Irvine, California, USA.
Surv Ophthalmol. 2004 Mar;49 Suppl 2:S62-72. doi: 10.1016/j.survophthal.2004.01.003.
Sutureless cataract surgery has been growing in popularity over the last decade. These clear corneal incisions allow for rapid visual recovery after phacoemulsification, but may be associated with an increased risk of endophthalmitis. The purpose of this study was to evaluate the effect of intraocular pressure (IOP), location, and angle of cataract incisions on wound apposition and sealing in postmortem globes.
This was an ex vivo laboratory investigation of 20 rabbit eyes and 14 human eyes. Self-sealing clear corneal, limbal, and scleral incisions were created and IOP was controlled with an infusion cannula. Incisions were made at a variety of angles. Optical coherence tomography was used to image the incisions in real time as the IOP was varied by raising and lowering the infusion bottle, so as to simulate the variation in IOP occurring with blinking or squeezing of the eye.
With each type of incision, optical coherence tomography demonstrated the dynamic nature of cataract wound morphology as IOP was varied. Higher IOPs, in general, were associated with more tightly sealed wounds than lower IOPs, but this varied according to the location and angle of the incisions. More perpendicular incisions, relative to the surface tangent, sealed less well than incisions created at smaller angles at higher levels of IOP; At lower IOPs, the reverse relationship was observed such that more perpendicular incisions sealed less well than smaller incision angles.
Changes in IOP may result in variable and sometime poor wound apposition in sutureless cataract incisions. The type of incision and angle of the incision may affect the likelihood of inoculation of the aqueous humor with potentially pathogenic bacteria. For each type of incision, there may be a critical angle at which the incision is better able to withstand fluctuations in IOP.
在过去十年中，无缝线白内障手术越来越受欢迎。这些透明角膜切口可使白内障超声乳化术后视力迅速恢复，但可能与眼内炎风险增加有关。本研究的目的是评估眼内压（IOP）、白内障切口的位置和角度对死后眼球伤口对合和密封的影响。
这是一项对20只兔眼和14只人眼进行的离体实验室研究。制作了自密封透明角膜、角膜缘和巩膜切口，并用输液套管控制眼内压。以各种角度进行切口。通过升高和降低输液瓶来改变眼内压，同时使用光学相干断层扫描实时成像切口，以模拟眨眼或挤压眼睛时发生的眼内压变化。
对于每种类型的切口，光学相干断层扫描显示随着眼内压的变化，白内障伤口形态具有动态特性。一般来说，较高的眼内压比较低的眼内压与更紧密密封的伤口相关，但这因切口的位置和角度而异。相对于表面切线，更垂直的切口在较高眼内压水平下的密封效果不如以较小角度制作的切口；在较低眼内压下，观察到相反的关系，即更垂直的切口比小切口角度的密封效果更差。
眼内压的变化可能导致无缝线白内障切口中伤口对合情况多变，有时甚至较差。切口类型和切口角度可能会影响房水被潜在致病细菌接种的可能性。对于每种类型的切口，可能存在一个临界角度，在该角度下切口更能承受眼内压的波动。
