Centre for Sight, East Grinstead, West Sussex, United Kingdom.
Singapore National Eye Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Singapore Eye Research Institute, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Duke-NUS Medical School, Singapore.
J Cataract Refract Surg. 2019 Mar;45(3):355-360. doi: 10.1016/j.jcrs.2018.09.027. Epub 2018 Nov 30.
To study the effects of anterior capsulotomy diameter and discontinuity on tear threshold load and distension for the technique of continuous curvilinear capsulorhexis (CCC).
Singapore National Eye Centre, Singapore, and CapsuLaser Inc., Livermore, California, USA.
Two separate randomized pairwise cadaver eye preclinical studies.
Capsulotomies were performed in 40 cadaver eyes of 20 donors using CCC. The pairwise comparisons were divided into 2 study groups: Study A: Continuous versus discontinuous capsulotomies; Study B: Capsulotomy diameter of 5.0 mm and smaller versus diameters of 5.2 mm and larger. A shoe-tree method was used to apply load to the capsulotomy rim, and the Instron tensile stress instrument measured threshold load and distension to initiate a capsular tear. Wilcoxon matched-pairs signed-rank tests were performed to assess statistical superiority.
In Study Group A, all pairs demonstrated that continuous capsulotomies were better than discontinuous capsulotomies for both the anterior tear threshold load and distension (P < .01). In Study Group B, 80% of the pairs demonstrated that diameters of 5.2 mm and larger were better than those of 5.0 mm and smaller diameter (P < .05).
Anterior capsulotomies behave as nonlinear elastic (elastomeric) systems when exposed to an external load and distension. This study demonstrated that continuous circular capsulotomies were more resistant to anterior tears than discontinuous capsulotomies. A point of irregularity or a defect in a capsulotomy rim has a high probability of being the tear initiation point. Furthermore, larger diameter capsulotomies were more resistant to anterior tears than smaller capsulotomies.
研究前囊切开直径和不连续性对连续曲线囊切开术（CCC）技术的撕裂阈值载荷和扩张的影响。
新加坡国家眼科中心和美国加利福尼亚州利弗莫尔的 CapsuLaser 公司。
两项独立的、随机的、配对的尸体眼前临床试验。
对 20 名供体的 40 只尸体眼使用 CCC 进行囊切开术。配对比较分为 2 个研究组：研究 A：连续与不连续囊切开术；研究 B：直径 5.0mm 及以下与直径 5.2mm 及以上的囊切开术。采用鞋楦法在囊切开缘施加载荷，Instron 拉伸应力仪测量引发囊撕裂的阈值载荷和扩张。采用 Wilcoxon 配对符号秩检验评估统计学优势。
在研究组 A 中，所有对都表明，对于前撕裂阈值载荷和扩张，连续囊切开术均优于不连续囊切开术（P<.01）。在研究组 B 中，80%的对都表明，直径 5.2mm 及以上的优于直径 5.0mm 及以下的（P<.05）。
当暴露于外部载荷和扩张时，前囊切开术表现为非线性弹性（弹性体）系统。本研究表明，连续圆形囊切开术比不连续囊切开术更能抵抗前撕裂。囊切开缘的不规则点或缺陷极有可能成为撕裂起始点。此外，较大直径的囊切开术比较小的囊切开术更能抵抗前撕裂。
