Qi Nan, Lockington David, Wang Lei, Ramaesh Kanna, Luo Xiaoyu
Institute of Marine Science and Technology, Shandong University, Qingdao, China.
Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, United Kingdom.
Front Physiol. 2022 Apr 8;13:834214. doi: 10.3389/fphys.2022.834214. eCollection 2022.
In a routine cataract operation cornea tissue may be damaged when an intra-ocular lens (IOL) injector of diameter between 1.467 and 2.011 mm is inserted through an empirically designed 2.2 mm corneal incision. We aimed to model and estimate the minimal length of the incision required to avoid wound tear. It was assumed that the damage was caused by tissue fracture at the tips of the incision, and this fracture could be studied using damage and fracture mechanics. The criterion of the damage was caused by a tear governed by the critical energy release rate (ERR) , which is tissue dependent. Analytical and numerical studies were both conducted indicating the possibility of a safe and effective incision in cataract surgery. Six commonly used IOL injection systems were examined. Our results suggested that the recommended 2.2 mm incision cannot be treated as a universal threshold. Quicker IOL insertion may reduce wound damage. It was also recommended to advance IOL injector its minor axis, and to cut the tear preferably along the circumferential direction due to tissue orthotropy. This study provides useful information and a deeper insight into the potential for mechanical damage to the corneal wound in cataract surgery.
在常规白内障手术中，当直径在1.467至2.011毫米之间的人工晶状体（IOL）注射器通过经验设计的2.2毫米角膜切口插入时，角膜组织可能会受损。我们旨在建立模型并估计避免伤口撕裂所需的最小切口长度。假设损伤是由切口尖端的组织断裂引起的，并且这种断裂可以使用损伤和断裂力学进行研究。损伤的标准是由临界能量释放率（ERR）控制的撕裂引起的，ERR取决于组织。进行了分析和数值研究，表明在白内障手术中进行安全有效的切口是可能的。检查了六种常用的IOL注射系统。我们的结果表明，推荐的2.2毫米切口不能被视为通用阈值。更快地插入IOL可能会减少伤口损伤。还建议沿IOL注射器的短轴推进，并由于组织正交各向异性，最好沿圆周方向切割撕裂处。这项研究为白内障手术中角膜伤口的机械损伤潜力提供了有用的信息和更深入的见解。
